Umeå University Odontological Dissertations, No 115

Dental caries and background factors in children with heart disease

Linda Rosén

Department of Odontology

Umeå University

Umeå 2011

Responsible publisher under swedish law: the Dean of the Medical Faculty

© 2011 Linda Rosén

ISBN: 978-91-7459-139-2

ISSN: 0345-7532

E-version available at http://umu.diva-portal.org/

Printed by: Print & Media

Umeå, Sweden 2011

If you want to study yourself — look into the hearts of other people.

If you want to study other people — look into your own heart.

Quote from Friedrich von Schiller

1

Abstract

Congenital heart disease (CHD) is one of the most common congenital

anomalies with an incidence of approximately 8–10 cases per 1000 live births.

Technical development and continuing improvement in surgical methods have

led to early interventions and an increased survival and consequently also a new

group of patients in dentistry. The general aim of this thesis was to study the

caries prevalence and some possible background factors in children with

complex CHD.

Paper I examined the caries prevalence in 41 children with complex CHD and

41 healthy age- and gender-matched controls. CHD children had higher dmfs-

values 5.2 ± 7.0 vs. 2.2 ± 3.5 in the controls (p < 0.05). CHD children on

digoxin medication had higher dmfs values 10.1 ± 8.5 vs. 3.7 ± 5.3 in the other

CHD children (p < 0.05). CHD children had received more fluoride varnish

treatments and fluoride tablets (p < 0.01).

Paper II investigated attitudes and experiences of dental health information and

advice, dental care, and service in 33 parents of children with complex CHD and

33 parents of age- and gender-matched controls. Differences were displayed in

the professional group that provided the parents with dental health information

and advice, attitudes to reception at the dental clinic, and experience of sedation

before operative dental treatment (p < 0.05).

Paper III examined 183 Swedish general dentists’ experiences of and attitudes

to dental care for children with CHD. Eighteen % of the dentists had received

special education or information to treat children with CHD, while almost half

of the dentists had one or more patients with CHD and a majority of them stated

that their CHD patients had a caries problem. The dentists had a different

opinion regarding the provision of dental treatment for children with CHD

compared to the current situation (p < 0.001).

Paper IV studied salivary secretion, salivary buffering capacity, viable count of

bacteria (TVC), mutans streptococci (MS) and lactobacilli (LBC), calcium,

chloride, magnesium, potassium, sodium, and IgA in 24 children on heart failure

medication and 24 healthy controls. Seven children (29 %) had stimulated

secretions below 0.5 ml/min compared to no child among the controls (p <

0.01). TVC were 1.4 × 106 ± 1.2 × 10

7 in the cardiac group vs. 2.7 × 10

6 ± 2.9 ×

107 in the control group (p < 0.05). MS ratio of TVC constituted 0.11 ± 0.35 %

vs. 0.01 ± 0.02 % for the controls (p > 0.05).

Paper V studied the endogenous pH and titratable acidity and dissolution of

calcium and phosphate from dental hard tissues by 13 pharmaceutical

preparations used in paediatric cardiology. Six of the preparations had an

endogenous pH below the critical value for enamel dissolution.

It is concluded that (i) children with complex CHD had a higher caries

experience in the primary dentition than healthy matched controls, (ii) children

on digoxin medication had a higher caries experience than other children with

2

complex CHD, (iii) children with complex CHD had received more caries

prevention than healthy controls, (iv) parents of children with complex CHD

were less satisfied with the reception and care they received than parents of

healthy children, (v) general dentists had a different opinion regarding the

provision of dental treatment to children with CHD compared to the current

situation (vi) children on heart failure medication can have a low saliva

secretion, (vii) pharmaceutical preparations used on long-term basis in paediatric

cardiology may pose a hazardous threat to dental hard tissues due to their

acidity.

Key words: attitudes, caries, children, dental care, heart disease, medication,

saliva

3

Contents

Abstract ........................................................................................................................... 1

Papers .............................................................................................................................. 5

Thesis at a glance ............................................................................................................ 6

Abbreviations .................................................................................................................. 8

Introduction ..................................................................................................................... 9

Signs and symptoms of heart disease ........................................................................ 11

Treatment of CHD ..................................................................................................... 11

Saliva ......................................................................................................................... 13

Dental caries .............................................................................................................. 15

Oral effects of pharmacotherapy ............................................................................... 19

Aims of the Thesis ........................................................................................................ 22

Materials........................................................................................................................ 23

Study designs ............................................................................................................. 23

Study and control groups........................................................................................... 23

Methods ......................................................................................................................... 26

Diagnosis, medication, and blood pressure ............................................................... 26

Caries registration (I) ................................................................................................ 26

Caries prevention (I) .................................................................................................. 26

Attitudes and experiences (II, III) ............................................................................. 27

Saliva (IV) ................................................................................................................. 27

Effects on dental hard tissues caused by medication (V) .......................................... 30

Ethical approval ......................................................................................................... 31

Ethical considerations ............................................................................................... 31

Statistical analyses ..................................................................................................... 31

Results ........................................................................................................................... 33

Discussion ..................................................................................................................... 38

Material and Methodological considerations ............................................................ 38

Evaluation of results .................................................................................................. 41

Clinical perspectives ................................................................................................. 47

Conclusions ................................................................................................................... 49

Populärvetenskaplig sammanfattning ........................................................................... 50

Acknowledgements ....................................................................................................... 51

References ..................................................................................................................... 53

APPENDIX I. Questionnaires Paper II ......................................................................... 59

APPENDIX II. Questionnaire paper III ........................................................................ 64

4

5

Papers

This thesis is based on the following original papers, which will be referred to

by their Roman numerals:

I. Stecksén-Blicks C, Rydberg A, Nyman L, Asplund S, Svanberg C.

Dental caries experience in children with congenital heart disease: a

case-control study. International Journal of Paediatric Dentistry 2004;

14: 94-100.

II. Grahn K, Wikström S, Nyman L, Rydberg A, Stecksén-Blicks C.

Attitudes about dental care among parents whose children suffer from

complex congenital heart disease: a case-control study. International

Journal of Paediatric Dentistry 2006; 16: 231-238.

III. Rosén L, Stecksén-Blicks C. Experience of dental care for children

with congenital heart disease among Swedish dentists. Swedish Dental

Journal 2007; 31: 85-90.

IV. Rosén L, Rydberg A, Sjöström I, Stecksén-Blicks C. Saliva profiles in

children using heart failure medication: a pilot study. European

Archives of Paediatric Dentistry 2010; 11: 187-191.

V. Rosén L, Rydberg A, Sjöström I, Lundgren T, Stecksén-Blicks C.

Acidity and in vitro effects on dental hard tissues of medicines used in

paediatric cardiology. Submitted.

The original papers are reprinted with kind permission from the publishers.

6

Thesis at a glance

Aims Material and Methods

I To study the caries prevalence in children

with complex CHD and compare with a

healthy age- and

gender-matched control group.

Each group comprised 41 children. Data were

collected from medical and dental records.

II To study attitudes and experiences of

parents of children with complex CHD with

respect to dental health information and

advice, dental care, and service and compare

with data from a healthy age- and gender-

matched control group.

Each group comprised parents of 33 children.

Data were collected with a questionnaire.

III To study experiences of and attitudes to

dental care for children with CHD among

Swedish general dentists.

General dentists from 2 Swedish counties

participated (n = 183). Data were collected with a

questionnaire.

IV To study saliva profiles in children on heart

failure medication and compare them with

healthy age- and gender-matched controls.

Each group comprised 24 children. Stimulated

saliva was collected. Salivary secretion rate,

buffering capacity, total viable count (TVC),

mutans streptococci (MS), lactobacilli (LBC),

calcium, chloride, magnesium, potassium,

sodium, and salivary IgA were determined.

V To study the endogenous pH, titratable

acidity, and dissolution of calcium and

phosphate from dental hard tissues by

pharmaceutical preparations used regularly

and on long-term basis in paediatric

cardiology.

Thirteen pharmaceutical preparations were

selected and the titratable acidity and the

dissolution of calcium and phosphate after

immersion of tooth specimens were quantified

for medicines with an endogenous pH below 5.5.

7

R

Results Conclusions

The dmfs-values were higher in the CHD group

(5.2 ± 7.0 vs. 2.2 ± 3.5, p < 0.05) while DMFS-

values not were different 0.9 ± 1.9 vs. 0.3 ± 0.6 (p

> 0.05). Children on digoxin medication had higher

dmfs values 10.1 ± 8.5 vs. 3.7 ± 5.3 (p < 0.05).

CHD children had received more fluoride varnish

treatments and fluoride tablets (p < 0.01).

Swedish children with complex CHD had more

caries in the primary dentition than healthy age-

and gender-matched controls in spite of

intensive preventive efforts.

A closer cooperation between paediatric

cardiology and paediatric dentistry is needed.

Differences were displayed in the professional

group that provided the parents with dental health

information and advice (p < 0.01) and attitudes to

reception at the dental clinic (p < 0.05). Parents of

children who were patients at a specialist clinic for

paediatric dentistry were more satisfied with the

reception compared to those who were patients in

the general dental practice (p < 0.01).

Parental attitudes to reception in the dental

service differed, and parents of healthy children

scored the reception at the dental clinic better

than parents of children with complex CHD. It

is suggested that children with complex CHD

should receive dental care in clinics for

paediatric dentistry particularly at early ages.

A minority of the dentists had received special

education to treat children with CHD. Almost half

of them had one or more patients with CHD. A

majority stated that their CHD patients had a caries

problem. The dentists had a different opinion

regarding the provision of dental treatment to

children with CHD compared to the current

situation (p < 0.001).

Data indicates that the Swedish dentists are

unsettled and insecure in the dental treatment of

children with CHD. Close cooperation between

specialists in paediatric dentistry, dentists with

special training, and general dentists is essential.

Twenty-nine % of the children on heart failure

medication had secretions below 0.5 ml/min

compared to no child in the control group (p <

0.01). TVC were lower in the cardiac group

compared to the control group (p < 0.05). MS ratio

of TVC constituted 0.11 ± 0.35 % vs. 0.01 ± 0.02

% for the controls (p > 0.05).

Children on heart failure medication can have a

low saliva secretion.

The pH of the pharmaceutical preparations varied

between 3.03 and 9.02 and 6 had an endogenous

pH below 5.5. The highest dissolved calcium and

phosphate from the tooth specimens was displayed

by captopril (12.5 mg) tablet water solution and by

the acetylsalicylic acid (75 mg) tablet water

solution.

Some pharmaceutical preparations used on a

long-term basis in paediatric cardiology may

pose a hazardous threat to dental hard tissues

due to their acidity.

8

Abbreviations

ACE Angiotensin-converting enzyme

ANOVA Analysis of variance

AS Aortic stenosis

ASD Atrial septal defect

BAO Blood agar oral plates

CFU Colony forming units

CHD Congenital heart disease

CoA Coarctation of the aorta

DCM Dilated cardiomyopathy

dmfs/DMFS Decayed, missed, filled surfaces for

primary/permanent teeth

ECC Early childhood caries

LBC Lactobacilli

LCC Late childhood caries

MS Mutans streptococci

PDA Patent ductus arteriosus

PDS Public dental service

PS Pulmonary stenosis

SWS Stimulated whole saliva

TGA Transposition of the great arteries

TOF Tetralogy of Fallot

TVC Total viable count

UWS Unstimulated whole saliva

VSD Ventricle septal defect

9

Introduction

The human heart develops between the 8th and the 12

th gestational week. A dis-

turbance in this process may result in an anomaly—a congenital heart disease

(CHD). CHD is one of the most common congenital anomalies in children, with

a mean incidence of approximately 8–10 cases per 1000 live births (1-4). Chil-

dren with complex anomalies constitute approximately one-third of all children

with CHD (3). Technical development and continuing improvement in surgical

methods have led to early interventions and an increased survival of children

with CHD (5). A majority of children with significant heart disease are today

subjected to successful surgery, but those children with very complex heart dis-

eases are often surgically palliated and not completely corrected (6, 7). The

aetiology behind cardiac developmental disturbances are in a majority of cases

unknown, but risk factors like maternal diseases and infections like diabetes,

rubella, HIV, and alcoholism have been suggested (4, 8). Many CHDs result

from genetic and environmental interactions rather than mendelian inheritance

(9). The CHD may occur individually as a single diagnosis, which is seen in a

majority of cases, or as a part of a syndrome or genetic malformation, e.g.

Down’s syndrome, Noonan’s syndrome, Turner’s syndrome, 22q11, and trisomy

18. Approximately 40 % of children with Down’s syndrome and a majority of

children with Noonan’s syndrome and trisomy 18 are affected with CHD (10,

11). Besides the group of congenital anomalies, heart disease in childhood may

also be caused by various kinds of cardiomyopathies leading to heart failure and

the need of anti-congestive medication (12).

CHD is the comprehensive term for congenital cardiac anomalies.

The most common anomalies can be divided into the sub-groups: left-right

shunts, obstructive heart diseases, and cyanotic congenital anomalies. The most

common diagnoses are listed in Table 1, and the frequency distributions of the

most common congenital cardiac diagnoses in live births are listed in Table 2.

10

Table 1. The most common cardiac diagnoses divided in sub-groups.

Left-right shunt Ventricle septal defect (VSD)

Atrial septal defect (ASD)

Patent ductus arteriosus (PDA)

Atrioventricular septal defect (AVSD)

Obstructive heart disease Coarctation of the aorta (CoA)

Aortic stenosis (AS)

Pulmonary stenosis (PS)

Cyanotic vitia Transposition of the great arteries (TGA)

Tetralogy of Fallot (TOF)

Table 2. Distribution of the most common congenital cardiac diagnoses in live

births according to the National Board of Health and Welfare (1).

Cardiac anomaly (%)

Ventricle septal defect (VSD) 20–30

Patent ductus arteriosus (PDA) 10–12

Atrial septal defect (ASD) 8–10

Pulmonary stenosis (PS) 8–10

Tetralogy of Fallot (TOF) 5–10

Coarctation of the aorta (CoA) 5–8

Atrioventricular septal defect (AVSD) 4–5

Transposition of the great arteries (TGA) 3–7

Aortic stenosis (AS) 3–5

Hypoplastic left heart syndrome (HLHS) 2–5

11

Signs and symptoms of heart disease

The main symptoms of CHD are cyanosis and/or heart failure. In cyanosis, de-

oxygenated blood is mixed with oxygenated blood or an increased amount of

blood goes to the pulmonary circulation. Low saturation in tissues and organs

may lead to acidosis, and this may cause an impaired heart function and heart

failure (4, 9).

Heart failure occurs either due to an increased blood flow to the

pulmonary circulation or due to a deteriorated ventricle, which fails to keep the

pumping function. Blood will accumulate in the lungs, and breathing will be

affected. The clinical signs are rapid breathing and an increased heart rate

(tachypnea and tachycardia), feeding problems, and inadequate weight gain. The

first signs of heart failure are often observed during the child’s first 3 months of

life.

Treatment of CHD

Pharmacological treatment

If left untreated, CHD is the single greatest cause of death during the neonatal

period after full-time pregnancies in the industrialized part of the world (4,9).

The medication is often complex in children with complex CHD, and the most

common pharmaceutical preparations used in paediatric cardiology can be found

in Table 3. Diuretics are the first treatment of choice in heart failure, decreasing

total blood volume and thereby diminishing the volume load of the heart. In

heart failure, medical treatment with angiotensin-converting enzyme (ACE)

inhibitors and/or cardiac glycosides, such as digitalis, can also be indicated.

ACE inhibitors inhibit the formation of angiotensin II, and as a result of this, the

peripheral resistance is decreasing both preload and afterload. Digitalis prepara-

tions reduce the heart rate and increase the contractility of the heart. Beta-

blockers are used in management of cardiac arrhythmias and may be indicated

as adjuncts to standard therapy in heart failure. Anticoagulants, as warfarin,

12

stops blood from clotting and antiplatelet drugs, such as acetylsalicylic acid,

decrease platelet aggregation formation. They are used in prevention of

thrombotic events in cardiovascular disease.

In duct-dependant anomalies, like in pulmonary atresia or hypo-

plastic left heart syndrome, it is of decisive importance that the ductus arteriosus

remains open, otherwise the child will die. In the late 1970’s, it was found that

prostaglandin keeps the ductus arteriosus open, and this finding has a key role in

the dramatically improved results of paediatric heart surgery. By giving

prostaglandin infusions, the child can be stabilized and transported to surgery

under considerably better circumstances.

Table 3. Pharmaceutical preparations used in paediatric cardiology.

Medicine Generic substances

ACE inhibitors enalapril

captopril

Diuretics spironolactone

furosemide

Beta-blockers metoprolol

propranolol

Cardiac glycosides digoxin

Anti-coagulants warfarin

Anti-platelet drugs acetylsalicylic acid

13

Surgical treatment

In 1938, the first paediatric heart surgery was performed. In 1953, the heart-lung

machine was used for the first time, and during 1970, the pacemaker and heart

transplantations on newborns were introduced in paediatric cardiology. In the

1980’s, catheter treatments of several CHD became possible. The use of

prostaglandin on duct dependent anomalies, as described earlier, taken together

with the development of the diagnostic instrument echocardiography, contrib-

uted to an increased survival rate of children subjected to paediatric heart

surgery. Figure 1 shows that the mortality rate decreased in children subjected to

open heart surgery in Sweden. Today surgery is successful for the majority of

children born with complex CHD (9). The median age of children subjected to

heart surgery is today below 2 years of age (4).

Fig. 1. Thirty-day mortality rate in children subjected to open heart surgery,

1988–2006 (data received from the National Board of Health and Welfare).

Saliva

To maintain a normal physiology in the oral cavity, an adequate salivary pro-

duction is of great importance. Saliva is produced by the 3 major pairs of

0

2

4

6

8

10

12

1988

1989

1990

1991

1992

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1994

1995

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1998

1999

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2004

2005

2006

Mo

rtal

ity

rate

(%

)

Year

14

salivary glands, namely, parotid, submandibular, and sublingual as well as by

numerous minor salivary glands, namely, buccal, lingual, labial, and palatinal, in

a total volume of 0.5–1.0 litre per day. The salivary glands seem to be fully de-

veloped at the age of 15, and the salivary flow rate increases with age and girls

have lower rates than boys (13). The saliva produced by the different gland

types has a characteristic composition, and the composition of the saliva has a

diurnal variation (14) and is affected by input stimuli (15). Saliva contains

inorganic components like calcium and phosphate and organic components like

proteins, carbohydrates, immunoglobulins, and enzymes. In the oral cavity, the

saliva from the salivary glands mixes with mucus from the nasal cavity and

pharynx, epithelial cells, and millions of microorganisms, and this mix is in the

literature referred to as whole saliva (14).

The salivary glands have a dual innervation with nerve fibres from

both sympathetic and parasympathetic nervous system. In general,

parasympathetic stimulation increases salivation, while sympathetic stimulation

produces more viscous saliva and therefore appears to depress salivation (14).

Pharmacotherapy is probably the most common cause of impaired salivary

secretion.

The saliva plays an important role in the complex oral ecosystem,

and several factors of great importance for maintaining oral health are present in

the saliva (16). One important objective of saliva in the defence against caries is

to neutralize acids in plaque, and an impaired salivary flow will result in an in-

creased risk of developing caries. Saliva acts as a lubricant for the oral tissues

and it facilitates swallowing and speech. Further, saliva contributes in the initial

step of digestive break down (14, 17). With its buffering capacity, saliva

protects the oral cavity against damaging pH changes. By several anti-microbial

components, such as immunoglobulins, the saliva also constitutes a barrier for

bacteria and viruses not to permeate the mucous membrane. Several types of

immunoglobulins are present in saliva, such as IgG, IgM, and IgA, of which the

15

secretory IgA (sIgA) is predominant (18). sIgA is produced by plasma cells

located in the connective tissues and is translocated through the duct cells of the

major and minor salivary glands (19, 20). Salivary IgA against mutans strepto-

cocci (MS) can be found in a majority of children over 3 years of age and the

amount increases with the length of exposure (18, 21).

Dental caries

Dental caries is defined as ‘a dynamic process taking place in the tooth bacterial

biofilm (plaque), which results in a disturbance of equilibrium between tooth

substance and the surrounding plaque fluid and finally results in a loss of

minerals from the tooth surface’ (22). Dental caries is one of the most prevalent

chronic and infectious diseases in man. Susceptibility to caries remains through-

out life, and it is the primary cause of oral pain and tooth loss in both the pri-

mary and the permanent dentition. The disease may be reversed if arrested in

time, but without proper care caries may progress until the tooth is destroyed

(23). Caries in young children may be divided into early childhood caries (ECC)

and late childhood caries (LCC) (24). Several studies have shown a close

relationship between caries in the primary dentition and caries in the permanent

dentition (25-28). The main assignment for paediatric dentistry is thus to

endeavour that dental caries never get established in the primary dentition.

Pathogenesis of dental caries

Dental caries develops in the interplay between acid-producing bacteria, e.g.

mutans streptococci (MS) and lactobacilli (LBC), dietary sugars that the bacteria

can metabolise, and several host or personal factors like teeth and saliva (23,

29). The most cariogenic group of bacteria present in the oral cavity is MS (30).

An increase in the proportion of acidogenic bacteria such as MS and LBC in the

oral biofilm has been shown to be associated with dental caries (31). Cariogenic

plaques normally contain high numbers of these bacteria and the acidogenic

16

potential is extensive. A shift in the composition of dental plaque towards

acidogenic bacteria occurs as an effect of environmental changes. Such changes

may occur due to reduced salivary flow, high and frequent intake of sucrose,

impaired oral hygiene or combinations of these factors (32-35). The low pH

generated from acids changes homeostasis in the microbial community in the

dental plaque and a selection towards bacteria with a capacity to induce caries

will take place. The acids produced by the cariogenic bacteria will cause a drop

in pH below the critical value where demineralisation of enamel occurs (pH ≤

5.5) (36). If the demineralization proceeds, cavitations in the tooth will be a fact.

On the other hand, if minerals in the saliva, like fluoride, calcium, and phos-

phate diffuse into the tooth, remineralisation occurs and the enamel turns more

acid-resistant. Remineralisation occurs frequently, especially when the biofilm

pH is restored by saliva, which acts as a buffer (36).

Risk factors

A potential risk factor is a variable associated with an increased risk of disease

or infection. The exposure must be established before the outcome and prospec-

tive studies are necessary to demonstrate risk factors, and they imply causality

(37). Low salivary secretion and high numbers of acid producing oral bacteria

are well-known risk factors for caries development. Risk factors for dental caries

may vary over time and are strongly affected by lifestyle and behavioural factors

that may expose the individual to risk factors. Poor oral hygiene habits, poor

dietary habits, and frequent use of medicines that contain sugar, are acidic,

and/or are xerogenic are examples of behavioural factors that may lead to an

increased caries risk (23).

17

Epidemiology

Several studies have reported the caries prevalence in Swedish children. Two

studies from 2006 and 2007 showed that 6–7 % of 2-year-old children have

caries (38, 39). Decreasing caries prevalence has been demonstrated in Swedish

children (40, 41). Caries prevalence and background factors were studied in a

series of cross-sectional studies from the northern part of Sweden in 4-year-olds

from 1967 to 2007. These studies showed a decreasing caries frequency over the

years, but it is also clear that caries is still a common problem in the primary

dentition (42). Many chronic diseases in childhood have been associated with

poor oral health (43). A number of studies have been carried out on the caries

prevalence in children with CHD (44-53) of which only five have been con-

trolled studies (44, 46-48, 52). Published studies on caries in children with heart

disease are presented in Table 4. In the controlled studies published between

1978 and 2008 from Australia and UK the severity of CHD and outcome

measures varies but the studies indicate more untreated caries, treatment need

and/or a higher caries prevalence compared to healthy children.

In Sweden, the caries distribution in children today is skewed, and

susceptible individuals like children with immigrant background (42) and some

medically compromised children (54-56) have more caries than non-immigrants

and healthy children. When this thesis was planned, little was known about the

caries prevalence in the increasing group of children with CHD in Sweden

where all children are offered organised dental care free of charge from an early

age.

18

Table 4. Published studies on caries in children with heart disease. Reference

number in parenthesis.

Author, year Country n Age Caries/age group

Berger, 1978 (44) Australia CHD=57

Ctr=57

8-10 Cyanotic CHD had higher

dt, DT and MT

Urquhart and

Blinkhorn, 1990

(45)

UK CHD=134 4-12 4-6 7-9 10-12

dmft DMFT DMFT

3.3 3.3 5.0

Pollard and Curzon,

1992 (46)

UK

Cardiac=100

Ctr=100

2-16 2-4 5-9 5-9 10-16

dmft dmft DMFT DMFT

1.8 4.3 * 0.6 1.8

1.6 2.8 0.5 1.6

Hallett et al, 1992

(47)

Australia

CHD=39

Ctr=33

2-15

1-15

dmft DMFT

4.2 * 0.9

2.3 0.6

Franco et al, 1996

(48)

UK

CHD=60

Ctr=60

2-16 dmft DMFT

3.7±3.2 2.7±3.4

3.9±3.2 2.0±2.9

untreated caries CHD=52 % *

Ctr=32 %

Hayes and Fasules,

2001 (49)

USA Children

scheduled for

cardiac

surgery=209

≥ 6

months

29 % with caries

Da Silva et al, 2002

(50)

Brazil Children with

risk of

IE=104

2-17 dmft DMFT

2.6±3.0 4.0±4.1

Balmer and

Bu´Lock, 2003 (51)

UK Children with

risk of IE=38

2-16 39 % with untreated caries

Tasioula et al, 2008

(52)

UK

CHD=76

Ctr=47

2-15

dmft DMFT Care index

1.6±3.0 0.8±1.4 10 % *

1.8±3.6 0.4±1.2 3 %

Rai et al, 2009 (53) India CHD=170 1-16 42 % with caries

* Statistically significant difference, IE=infective endocarditis

19

Caries prevention

The dental care for Swedish children has had a preventive approach for more

than 40 years with start in an early age of the child. The concept with an early

prevention start is based on the thought that initially children’s teeth are healthy

and that the dental health of the preschool child is important since it has a strong

influence on the future dental health (25-28). The beneficial development of the

dental health of preschool children during the 1970’s has been ascribed to the

introduction of early dental health information to parents and an increased use of

fluorides (57). Fluoride plays an important role in caries prevention (58, 59) and

stimulates self healing of minor cavities by reducing the demineralisation

process and promoting the remineralisation process (60). Further, fluoride also

affects the metabolism in caries-associated bacteria (61). The effect of fluoride

strongly depends on the frequency of administration. Fluoride toothpaste is

considered as the most cost-effective homecare measure (58), and semi-annual

fluoride varnish applications, as the best professional method for infants at risk

(62). In a group of special-needs children, the beneficial effect of daily fluorides

was demonstrated, and it was shown that both fluoride tablets and fluoride liquid

could prevent ECC in children with cleft lip and/or palate (63). In Sweden, basic

caries prevention in healthy individuals consists of tooth brushing twice a day

with fluoride toothpaste. In individuals with an increased risk for caries, like

some medically compromised patients (43, 54-56), additional fluoride may be

indicated and is suggested to be administered based on individual needs and

compliance (24).

Oral effects of pharmacotherapy

It is known that children with very complex CHD frequently require regular

long-term medication (7), but the knowledge of oral health effects caused by

long-term medication in medically compromised children is sparse (64). Many

pharmaceutical preparations used on a long-term basis may have a low pH, high

20

acidity, and contain sugar (65, 66). A strong correlation between xerostomia and

pharmacological treatment has been shown (67), and a number of drugs have

been listed as xerogenic (68). These drugs include those with a direct damage to

salivary glands such as cytotoxic drugs, drugs with anticholinergic activity,

drugs which deplete fluid as diuretics, and drugs acting on sympathetic system

like antihypertensive drugs (69). Only a few clinical studies have been carried

out on the outcome of salivary function with antihypertensive drugs, and the

outcome is not clear-cut (70). In healthy men, the effects of β-adrenoceptor

antagonists, such as atenolol and propranolol, on saliva flow and composition

was tested and no effect on saliva secretion was found; however, there was a

reduction in total salivary protein (71) and hypertensive patients increased their

salivary secretion during withdrawal of β1-selective drug metoprolol (72). Treat-

ment with the ACE inhibitor captopril increased the secretion rates for unstimu-

lated and paraffin-chewing stimulated whole saliva and for parotid secretion. No

alterations in the composition of saliva were observed (73). Thiazide diuretics

significantly reduced salivary secretion in 34 healthy adult volunteers (74).

To maintain chemical stability, control tonicity, and physiological

compatibility in medicines, acids are frequently used as buffering agents (64).

Fermentable sugars such as sucrose can also be added in paediatric medicines to

disguise their unpleasant taste and thereby facilitate compliance. Sugars in

medicines may, however, cause a pH drop in the oral biofilm as a result of their

fermentation in acid-producing bacteria (23, 43), and acids in medicines may

help to prolong the pH drop after a sugar challenge. Pharmacotherapy may

therefore, beside the effects on salivary secretion, also act directly on the dental

hard tissues with dental caries and/or erosive lesions as possible outcomes as a

result of their content of acids and fermentable sugars (66, 68, 75, 76). Dental

erosion is a multifactorial condition, defined as the ‘dissolution of the tooth by

acids when the surrounding aqueous phase is unsaturated with respect to tooth

mineral’ (77). Minerals in dental hard tissue are dominated by calcium and

21

phosphate mainly organised in hydroxyapatite crystals with a critical pH value

of 5.5 (36). Any substance with an endogenous pH below this value may cause

ionic dissolution of the hard tissue with caries and erosion as possible outcomes

(78). The causes behind the development of dental erosion are often divided into

either extrinsic or intrinsic factors. Extrinsic factors are factors like acidic food-

stuffs and medications. Intrinsic factors may be diseases and consequences of

diseases where acidic contents of the stomach reach the oral cavity and thereby

pose a threat to the oral health (79).

22

Aims of the Thesis

General aim

The general aim of this thesis was to investigate the caries prevalence in

children with complex CHD and potential background factors.

Specific aims

The specific aims of this thesis were to:

Study the caries prevalence in children with complex CHD and compare

with healthy age- and gender-matched children.

Study the attitudes and experiences of parents whose children have

complex CHD with respect to dental health information and advice, dental

care and service, and to compare the results with data from a healthy age-

and gender-matched control group.

Study the experience of and attitudes to dental care for children with CHD

among Swedish general dentists.

Study the secretion and composition of saliva in children on heart failure

medication, and to compare with saliva from healthy age- and gender-

matched controls.

Study the endogenous pH, titratable acidity, and dissolution of calcium

and phosphate from dental hard tissue by medicines used regularly and on

long-term basis in paediatric cardiology.

23

Materials

Study designs

• Study I, II and IV: Cross-sectional case-control design.

• Study III: Descriptive cohort study.

• Study V: In vitro study.

Study and control groups

Table 5. Number of invited, consented, gender distribution, and mean age.

Equal numbers and gender in study and control groups.

Study Invited Consented Boys Girls Mean age, range

(yrs)

I 43 41 25 16 6.5 (2–11)

II 38 33 20 13 9.4 (3–13)

IV 37 24 11 13 12.0 (6–19)

Paper I

All surviving children with CHD, complexity grading II and III, born between

1991 and 2000 and living in the county of Västerbotten were selected from the

Paediatric Cardiology Outpatient Clinic at University Hospital in the city of

Umeå, Sweden and invited to take part in the study (n = 43). Children with other

serious medical diagnoses and children with learning difficulties were excluded.

For each CHD, a healthy child with the same date of birth and gender was

selected. The first child in the population register who met the inclusion criteria

was included in the control group. Informed consent was received from the

parents of 95 % of the selected groups, which resulted in 41 children in each

24

group. The mean age of the children was 6.5 years, and there were 25 boys and

16 girls.

Paper II

Parents of all children with CHD between 3 and 13 years of age, complexity

grading II and III, without other chronic diseases, learning difficulties, or

syndromes registered in the Paediatric Cardiology Outpatient Clinic at

University Hospital in the city of Umeå were invited (n = 38). The parents of 2

children with CHD did not consent. For each child in the study group, a child of

the same gender and date of birth was selected from the population register for

the county of Västerbotten. Approximately 50 % of the parents replied to the

first questionnaire. After reminders 10 participants did not reply, and they were

exchanged with the parents of the next child with the same birth date and gender

in the population register. In spite of this, there were 3 non-respondents. To

match the controls, the parents of 3 children with CHD were excluded. The final

material thus consisted of 33 pairs of parents.

Paper III

All general dentists employed in the Public Dental Health Service and all private

dentists listed with dentistry for children in the county of Västerbotten (n = 145)

in the north of Sweden and all general dentists employed in the Public Dental

Health Service in the county of Uppsala (n = 100) in the middle of Sweden were

invited to participate in the study. All specialists were excluded from the invita-

tion. The final material consisted of 183 dentists (75 %) of which 40% were

males and 60 % were females. Seventy-two % of the dentists had their dental

degree 16 years ago or earlier, and 10 %, six years earlier or less.

25

Paper IV

All children with CHD complexity grading II and III, or dilated

cardiomyopathies (DCM), 5 years or older, medicating with ACE inhibitors

and/or diuretics, and attending the Paediatric Cardiology Clinics at the

University Hospital in the city of Umeå or at the Karolinska University Hospital,

Stockholm, Sweden, were invited to take part in the study (n = 37). Children

with other chronic diseases, learning difficulties or syndromes were not invited.

Each child in the study group who fulfilled the criteria for inclusion and con-

sented to participate was asked to bring along a friend, healthy, with the same

age and gender, to the saliva-sampling occasion. The final material consisted of

pairs of 24 children (65 %). Three cases were 1 year younger or older than their

control.

Paper V

Thirteen medicines commonly used in paediatric cardiology were selected. For

quantification of dissolution of calcium and phosphate, tooth specimens were

prepared from the central corona of extracted primary canines with no cracks in

enamel.

26

Methods

Diagnosis, medication, and blood pressure

Data on diagnosis, medication, and blood pressure in the study groups were ex-

tracted from the records at the Paediatric Cardiology Clinics at the University

Hospital in Umeå and at the Karolinska University Hospital, Stockholm,

Sweden. Data extraction was performed by an experienced paediatric

cardiologist.

Caries registration (I)

For both groups of children, copies of their dental records and bitewing radio-

graphs were collected from the dental clinic where the child received dental

treatment. Data on decayed, missing, filled, and carious surfaces (dmfs/DMFS)

were collected from the records, while data on posterior approximal caries were

collected from bitewing radiographs. The examiner was blinded to group when

reading the bitewing radiographs. All initial (in the enamel) and manifest (in the

dentine) caries lesions on approximal surfaces in posterior teeth, i.e. primary

molars in the primary dentition and first permanent molars, were included in the

dmfs/DMFS values. A primary molar that had been extracted due to caries was

counted as 3 missing surfaces in the dmfs values.

Caries prevention (I)

Data on the number of occasions the child had been treated with fluoride varnish

and professional polishing was noted from the dental records, as well as the

number of prescriptions of fluoride tablets.

27

Attitudes and experiences (II, III)

Paper II

A questionnaire with 20 questions was used for both groups of children.

Thirteen of the questions concerned dental health information and dental care

and service. Both groups were also asked 7 questions about dental health of the

child and his/her parents, the children’s and parents’ expectations before visits to

the dental clinic, and the educational level of the parents. In the questionnaire to

the parents of the children with CHD, 4 specific questions were added, con-

cerning if the child with CHD had siblings, the differences in dental health in-

formation compared to healthy siblings, parents’ knowledge about antibiotic

prophylaxis, and where they had received this information.

Paper III

The invited dentists were sent written information about the purpose of the study

and were asked to fill in a questionnaire. The questions were pre-tested in a

group of experienced clinicians, and a few changes were performed in the

questionnaire before data collection. The questionnaire had 18 questions con-

cerning the dentists’ experiences and attitudes to dental care for children with

CHD as well as the dentists’ age, gender, and year of graduation. Two reminders

were sent out to non-responders.

Saliva (IV)

Saliva sampling

Stimulated whole saliva (SWS) was collected before lunchtime, and the partici-

pants were asked to refrain from all eating, drinking, and tooth brushing at least

1 hour before sampling. Age, general health, and medication were checked for

the accompanying control.

SWS was collected by chewing on a standardised lump of paraffin.

Instructions were given to chew for 1 minute and thereafter to spit out or

28

swallow any saliva produced. The subject was then asked to chew paraffin for 5

minutes and to collect all saliva that was produced in a test tube. The saliva

samples were assessed for salivary secretion rate (ml/min), buffering capacity,

electrolyte concentration, salivary IgA, total viable counts (TVC), and caries-

associated bacteria, namely, MS and LBC. The secretion rate and buffering

capacity were determined at the sampling occasion, and the samples were then

transported to the laboratory at the department of Paediatric dentistry at Umeå

University for cultivation of oral bacteria. Saliva for assessment of electrolyte

concentrations and salivary IgA was stored frozen until the sampling was

finalized.

Assessment of stimulated saliva secretion rate and buffering capacity

The volume of the produced saliva was immediately measured and the secretion

rate was calculated (ml/min). A drop of saliva from the test tube was applied to a

Dentobuff Strip test pad (Orion Diagnostica Oy, Espoo, Finland) and the colour

of the pH pad was read and compared with the manufacturer’s colour chart.

Cultivation of bacteria

After sampling, the saliva samples were serially diluted in a potassium

phosphate buffer with NaCl to obtain 0, 40, 800, and 8000 times dilutions. MS

were cultivated on selective (MSB) agar (Difco Mitis Salivarius Agar, Becton,

Dickinson and Company, USA) and LBC were cultivated on Man, Rogosa,

Shape (MRS) agar (Merck, Germany). TVC were cultivated on blood agar oral

plates (BAO). All plates were incubated aerobically in 37 ˚C in 5 % CO2 for 48

hours and then examined under a light microscope to verify the colony forming

units (CFU). The total number of CFU in saliva was calculated as CFU/ml of

saliva.

29

Determination of the salivary composition of electrolytes

The saliva samples were diluted 1:1 with MQ-distillated water and centrifuged

at 13200 rpm for 10 minutes and then stored frozen (-20 ˚C) until all samples

were collected. All analyses of the electrolytes were performed in the same

session. Calcium and magnesium were measured by atomic absorption with an

acetylene flame, with a standard curve in the range of 0.8–1.5 mM total calcium

and 0.05–0.21 mM total magnesium. Sodium and potassium concentrations were

measured in the same way at 589.6 nm and 769.9 nm respectively, with a

standard curve in the range of 4–40 mM total sodium and 14–26 mM total

potassium. Chloride was measured indirectly by precipitation of silver at 328.1

nm, with a standard curve in the range of 9–34 mM total chloride. Phosphate

was determined spectrophotometrically at 700 nm with a standard curve in the

range of 2.2–5.7 mM total phosphate.

Determination of salivary IgA

The saliva for determination of salivary IgA was diluted, centrifuged, and stored

frozen as saliva for determination of electrolytes. As a standard preparation, a

purified human colostral IgA Sigma no 1-3755 was used. The salivary IgA

concentrations were calculated by reference to this standard. As a primary anti-

body, an affinity purified anti-human IgA α (alpha chain specific) from goat was

used, and as a secondary antibody, a peroxidased conjugated affinity purified

goat anti-human IgA α (alpha chain specific) was used. The analyses were per-

formed in triplets on Elisa plates, leaving the first wells as blanks. The IgA con-

centrations were determined spectrophotometrically at 490 nm, providing a

mean value for the sample in mg/l.

30

Effects on dental hard tissues caused by medication (V)

Medicines, sample preparation, and pH measurement

Of the 13 selected medicines, there were solid tablets (n = 7), capsules (n = 2),

and mixtures (n = 4). Citric acid (10 mM) was used as control. Tablets were

crushed in a mortar and dissolved in 10 ml of distilled water. For liquid medi-

cines, a 10 ml sample was taken. The endogenous pH values of the water solu-

tions of tablets or liquid medicines were measured with a pH meter.

Titration

Each medicine sample was titrated by adding 0.01 ml aliquots of a NaOH

solution (0.1 M) by using a titrator. The pH value achieved for each 0.01 ml

NaOH added was read with the pH meter and recorded. The titration was per-

formed until a pH value of 7.0 was reached. Samples with an endogenous pH

value > 5.5 were not titrated.

Loss of calcium and phosphate after immersion of dental hard tissue in

medicines

For medicines with a pH below 5.5, the dissolution of calcium and phosphate

after immersion of tooth specimens were quantified. Specimens were prepared

from the central corona of extracted primary canines with no cracks in enamel.

The teeth were embedded in Epofix (Struers, Ballerup, Denmark) and 3 hori-

zontal slices (thickness 80 µm) were cut from each tooth under water-cooling.

Prior to the experiment, the tooth specimens were pre-treated with immersion in

1 mM CaHPO4 + 1 mM F overnight in room temperature. Tablets were crushed

in a mortar, diluted in 2 ml MQ-water and rocked overnight in room tempera-

ture. Calcium and phosphate were analyzed as in Paper IV. First, the baseline

calcium and phosphate content of medicine solutions were measured in 100 µl

of each sample. Thereafter, 500 µl of each medicine solution was transferred

into cell cultivation chambers, and 2 chambers were filled with each medicine.

31

One tooth disc was put into each chamber and the plate was placed in 37 ˚C.

One hundred µl were collected from each chamber after 30 minutes of immer-

sion and analysed. The mean of 2 samples for each medicine was calculated.

Ethical approval

The protocols of studies I and II were approved by the Research Ethics

Committee of the Faculty of Medicine and Odontology at Umeå University and

IV was approved by the Regional Ethical Review Board at Umeå University.

For Paper V prior to the extractions for orthodontic reasons the patients and their

parents were informed about that the teeth should be used for research purposes

and consent were obtained. For paper III no ethical approval was applied for.

Ethical considerations

Informed consent from all the participating children and their parents was ob-

tained before the start of clinical studies in Paper I, II, and IV. The parents were

informed that participation was voluntarily, and any time the study could be

terminated, and the CHD group termination could be performed without harm to

the doctor-patient relation. As families with children with serious heart diseases

face heavy demands due to their surgery, medication, recurrent illness, and

occasional nutritional problems, the added burden the participation in these

studies constituted were carefully considered when the studies were planned. As

the caries problem constitute a considerably add to their burden the potential

medical benefits of these studies were considered to outweigh encroach in their

privacy.

Statistical analyses

All data were processed with the SPSS (versions 11.0-17.0, SPSS Inc., Chicago,

IL, USA).The following statistical analyses were performed: Paper I—One-way

32

analysis of variance (ANOVA) was used to compare the differences between

groups, and Spearman’s rank correlation was used to explore the relationship

between dental caries and selected variables. Chi-Square test was used to test the

differences between groups in the use of fluoride tablets. Paper II—Fischer’s

exact test (2-sided) was used to test the differences in standardised answers

between the 2 groups. Paper III—Chi-Square test was used to test the

differences between groups. Paper IV—Continuous data were analysed by

ANOVA, and categorical data, by chi-square test. In paper V, only descriptive

data were presented. In all statistical analyses, a p-value of less than 0.05 was

considered statistically significant.

33

Results

Paper I

Data for dmfs and DMFS are given in Table 6. All dmfs indices were

statistically significantly higher in the CHD group (p < 0.05), while no

statistically significant differences could be displayed for any of the DMFS

indices (p > 0.05). The number of months the child had been on digoxin

medication and the dmfs value had a statistically significant positive correlation

(r = 0.368, p < 0.05). Ten of the children in the CHD group had been on digoxin

medication between 6 and 87 months. This sub-group had a statistically

significant higher mean dmfs value compared to those children in the CHD

group who did not medicate with digoxin (10.1 ± 8.5 vs. 3.7 ± 5.3, p < 0.05).

The children in the CHD group had achieved statistically significant more

treatments with fluoride varnish and prescriptions of fluoride tablets compared

to the control group. The mean number of treatments with fluoride varnish was

3.8 ± 4.0 for children in the CHD group compared to 1.8 ± 2.2 in the control

group (p < 0.01). Fifty-two % of the children in the CHD group had been

prescribed fluoride tablets on one or more occasions compared to 17 % in the

control group (p < 0.01). There was a significant positive correlation between

the numbers of fluoride varnish treatments and the dmfs value of the child (r =

0.411, p < 0.01).

34

Table 6. dmfs and DMFS in the CHD group and the control group.

n CHD Control p

dmfstot

41

5.2 ± 7.0

2.2 ± 3.5

<0.05

dmfsdentine

41 4.7 ± 6.3 2.1 ± 3.4 <0.05

dmfsapproxtot *

41 3.4 ± 4.0 1.5 ± 2.8 <0.05

dmfsapproxintit *

DMFStot

41

26

0.5 ± 1.0

0.9 ± 1.9

0.1 ± 0.3

0.3 ± 0.6

<0.05

>0.05

DMFSdentine

26 0.6 ± 1.7 0.3 ± 0.6 >0.05

DMFSapproxtot *

26 0.1 ± 0.7 0.1 ± 0.2 >0.05

DMFSapproxintit *

26 0.1 ± 0.7 0.0 ± 0.0 >0.05

* approximal surfaces in canines, premolars, and molars

Paper II

Statistically significant differences were displayed in the professional group that

provided the parents with dental health information and advice, attitudes to re-

ception at the dental clinic, and experience of sedation before operative dental

treatment (p < 0.05). Parents of children with CHD who were patients at a

specialist clinic for paediatric dentistry scored the reception at the dental clinic

higher than those who were patients in general dental practice. This difference

was statistically significant (p < 0.01). No statistically significant differences in

educational level or parental experience of dental health were noted between the

2 groups (Table 7), (p > 0.05).

35

Table 7. Educational level and reported dental health in parents of the CHD

children and controls.

CHD

%

Control

%

p

Educational level of the mother

9 years

12 years

University/college

12

52

36

3

53

44

0.481

Educational level of the father

9 years

12 years

University/college

13

64

23

7

53

40

0.223

Dental health of the mother

No problems

Some problems

Large problems

61

30

9

63

25

12

0.872

Dental health of the father

No problems

Some problems

Large problems

76

24

0

63

31

6

0.400

Paper III

One-fifth of the dentists stated that they had received special education or in-

formation, except the graduate training, to treat children with CHD. Almost half

of the dentists had one or more patients with CHD, and a majority of these stated

that their CHD patients had a caries problem. Only 34 % knew that some of the

medicines used by CHD patients could increase the risk for caries. One-third of

the dentists (33 %) reported that the level of dental care for children with CHD

did not differ compared to healthy children at their clinic, and 42 % of the den-

tists reported that more caries prevention were given compared to healthy

children. Seven % of the dentists reported that shorter recall intervals were given

to children with CHD, while 16 % gave the answer that they did not know.

36

Statistically significant differences were displayed between the answers to the

questions ‘who in the dental team perform the major part of dental care for

children with CHD’ and ‘what is your opinion on who should perform the major

part of the dental care for this group of children’ (p < 0.001). Among dentists

whose clinical time mainly was used for dentistry for children, it was more

common to treat children with CHD than for dentists with less time with

dentistry for children (p < 0.001).

Paper IV

Seven of the children (29 %) on anti-congestive medication had secretion rates

below 0.5 ml/min compared to no child in the control group (p < 0.01), (Fig 2).

Four cases had the same secretion rate as a control with the same age. There

were no statistically significant differences concerning mean salivary secretion

rate, buffering capacity, calcium, chloride, magnesium, phosphate, potassium,

sodium, or salivary IgA concentrations (p > 0.05). TVC differed statistically

significantly between the 2 groups, 1.4 × 106 ± 1.2 × 10

7 in the CHD group vs.

2.7 × 106 ± 2.9 × 10

7 in the control group (p < 0.05). The MS levels were 5.2 ×

104 ± 1.5 × 10

5 in the cardiac group vs. 8.1 × 10

3 ± 1.3 × 10

4 in the control group

(p > 0.05), and the MS ratio of TVC constituted 0.11 ± 0.35 % compared to 0.01

± 0.02 % for the control group (p > 0.05).

37

Fig. 2. Stimulated salivary secretion rate by age in children with heart disease on

heart failure medication and healthy age- and gender-matched controls. Filled

circles show cases, unfilled circles show controls.

Paper V

The endogenous pH values varied between 3.03 and 9.02 of the 13 medicines

that were studied. Six of these (46 %) had an endogenous pH below the critical

pH of 5.5. The lowest pH was recorded for the captopril 12.5 mg tablet water

solution, while the propranolol hydrochloride mixture displayed the highest ti-

tratable acidity. The highest dissolved calcium and phosphate from the tooth

specimens was displayed for the captopril (12.5 mg) tablet water solution 1.9

mM and 1.1 mM, respectively, and with the acetylsalicylic acid (75 mg) tablet

water solution, 1.6 mM calcium and 0.7 mM phosphate were dissolved.

age

17,51512,5107,5

secre

tio

n m

l/m

in

4,00

3,00

2,00

1,00

0,00

38

Discussion

Material and Methodological considerations

Study designs and study groups

For the studies in Paper I, II, and IV in this thesis, a case-control study design

was chosen. Case-control studies can be used to study risk factors by compari-

sons of individuals who have a condition (the cases) with patients who do not

have the condition but are otherwise similar (the controls) (80). Data for each

case-control pair are assessed and are then aggregated. Case-control studies are

relatively inexpensive and can be carried out by small teams or individual re-

searchers in single facilities in a way that more structured experimental studies

often cannot be. They have pointed to a number of important discoveries, but the

hierarchical level of scientific evidence is considered to be relatively low be-

cause of the retrospective exposure, non-randomized nature, and often blinding

not is possible. The shortcomings in the case-control design can be overcome by

cohort study design were exposed and non-exposed are compared. Cohort

studies are however often not possible for practical reasons when the disease is

rare.

Study III examined the experience of dental care for children with

CHD among Swedish general dentists using a descriptive cross-sectional design.

Cross-sectional studies performed with convenience samples cannot be

generalized to the entire population. However, they can identify risk indicators

of those parameters that are significantly associated with the condition being

investigated. One benefit of cross-sectional studies is that they are considered to

be hypothesis-generating (80).

Using plaque pH measurements (81) in Paper V could have given in-

formation of the in vivo effects of medication. This experiment was considered,

but due to the added burden, the participation would have implied for this medi-

cally comprised group, we decided to give up the idea. As the composition of

teeth is variable, due to genetic influences, environmental conditions, and post-

39

eruptive maturation and dentin sclerosis, such differences may lead to large

variations in their response under acidic challenges. The in vitro design that

made it possible to pre-treat the tooth specimens, with immersion in a calcium

phosphate medium, helped to increase the standardization of the specimens.

Clinical decision making should ideally be based on powered high-

quality studies. Using a multicenter approach in Paper I could have made it pos-

sible to include more individuals. As the study group in Paper I included all

children with complex CHD in the area who fulfilled the inclusion criteria, ex-

cept 2 whose families did not give consent to their child to participate, a multi-

center approach was not considered. It is possible however, that the caries

experience in the permanent dentition also would have reached a statistically

significant difference with increased numbers. In Paper II, among the 38 invited

parents, there were only 2 who did not give consent. To match the controls,

parents of 3 children with CHD were excluded. In Paper IV, a multicenter

approach was used for increasing power and significance, as children who ful-

filled inclusion criteria in the county of Västerbotten was limited. In Paper III,

75 % of the invited dentists responded, and the non-responding rate is

considered acceptable for a study based on a questionnaire (82).

Caries registration

Caries were assessed from recordings in dental records and bitewing radiographs

in the Public Dental Service (PDS). Ideally, the same examiner would have ex-

amined all the children in both groups to remove the effects of variation in caries

diagnosis between different examiners. As the children had many medical

contacts already, it was considered unethical to add to their burden. The study

was, therefore, performed on data that had already been collected at the dental

clinics, despite the disadvantages of this procedure. Partly to reduce the effect of

variation in caries diagnoses, all data on posterior approximal caries were col-

lected by one of the authors from bitewing radiographs for both groups of

40

children. In order to increase the level of evidence, all reading of bitewing

radiographs were performed blinded to the examiner, and initial caries were an-

alysed separately.

Saliva collection, cultivation of bacteria, and analysis of saliva

Measurement and analysis of saliva is non-invasive, fast, and cost-effective

diagnostic tool. The salivary secretion rate varies during the day and is affected

by temperature, fluid balance, state of health, frame of mind, and medication.

Hence, the collection of saliva should be standardized so that the results can be

comparable with those from other clinical investigations (14, 20). To meet this,

all saliva samples in study IV were collected before lunchtime and the partici-

pants were asked to refrain from eating, drinking, and tooth brushing 90 minutes

before sampling.

Saliva may be collected as whole saliva or as selectively collected

secretion from specific salivary glands. In the clinic, whole saliva secretion

often is used to asses salivary flow rate, and buffer capacity. Whole saliva can

be collected as unstimulated whole saliva (UWS) or stimulated whole saliva

(SWS). The total volume of saliva collected is expressed as ml/min. An UWS

rate less than 0.1 ml/min is considered a risk value (20). A SWS of 1–3 ml/min

is considered normal and 0.7 ml/min and below is considered a risk value for

caries (83). For schoolchildren, a cut-off of less than 0.5 ml/min is considered

low with regard to caries risk (24).

Questionnaires

There are several methods available to collect qualitative data such as attitudes

and experiences, for example, questionnaires and interviews. Both strategies for

data collection have strengths and shortcomings. The questionnaire can be dis-

tributed in groups or geographic areas and the method is proportionately cost-

effective. Standardized questions can be formulated, that is, all questions and

41

responding-alternatives are presented in the same way for every respondent. The

strengths with interviews on the other hand are that the questions can be formu-

lated in a more detailed way, there is a possibility to ask follow-up questions,

and the non-responding rate is often lower in interviews compared to

questionnaires.

When designing a questionnaire, great effort has to be made when

formulating the questions. The questions should be unambiguous, not leading,

and formulated in a language suited to the target group. The questionnaire

should be followed by a prepaid envelope and a letter. Two reminders are

considered normal (82, 84).

Evaluation of results

In Papers I, II and IV a null-hypothesis was tested and could be rejected for

some of the primary outcome measures as caries experience, attitudes and

experiences of dental care and saliva secretion.

Paper I shows that caries is a common oral health problem in

Swedish children with complex CHD, especially at early ages, and it confirms

findings from studies with different study designs, inclusion criterias, outcome

measures and from countries with differing dental care system (44-53). The

difference in caries prevalence between Swedish children with CHD and healthy

controls was larger than that shown in a British study with a similar design as

ours (48), which only showed more untreated caries in children with CHD. The

high caries frequency is not acceptable and calls for strategies for disease

control.

Due to the great progress in surgical techniques and intensive care

for infants with CHD, the number of surviving children is increasing (1). Groups

of medically compromised children such as immuno-compromised from disease

and/or therapy and children with complex CHD have an increased risk of

42

developing systemic complications from dental infections, which may prove

fatal (43). Poor dental health gives an increased risk of dental bacteraemia that

may lead to infective endocarditis, and healthy teeth may decrease this risk.

Dentists are advised to provide antibiotic prophylaxis against endocarditis in

many of the children with complex CHD, before invasive dental procedures (1).

Healthy teeth among CHD children may contribute to a decrease in the use of

antibiotics for dental/oral infections. Healthy teeth also decrease the need of

general anaesthesia and tooth extractions, which may be more complicated in

complex CHD because of the increased medical risks with general anaesthesia

and the risk of prolonged bleeding amongst children on anti-coagulants and anti-

platelets. Siahi-Benlarbi et al (85) assumed that high levels of oral Candida,

which are associated with caries (86-88), and its descending/resorption through

the gastrointestinal tract may lead to serologic Candida accumulation or

candidiasis. Therefore, a healthy oral cavity (especially before and after heart

transplantation) is an important precondition to prevent Candida infections since

these infections are opportunistic and when the immune system is depressed an

acute infection may occur. Of major significance is also the fact that untreated

caries can be a contraindication for heart surgery and as patients with more

complex anomalies often require several surgical interventions, it is particularly

important that scheduled surgery does not have to be postponed because of

dental disease.

The dental care for children in Sweden is organized by the county

councils and is free of charge. The parents can choose between dental care for

their children organized within the PDS or by private clinics. Around 90 % of

the dental care for children in Sweden is provided within the PDS. The dental

care system offers all children a comprehensive dental care between the ages of

3 and 19 years. The care has a strong preventive approach from an early age,

and all parents are offered dental health information when the child is between

1- and 2-years-old. A common clinical experience in children with CHD is that

43

their parents do not attend this early dental health information and, thus, they do

not benefit from early oral health promotion to the same extent as most

individuals. Paper I showed that children with complex CHD had received more

caries prevention than the healthy controls, and there was a positive correlation

between the caries prevalence and number of fluoride varnish treatments, but the

care had been offered when caries already had become a problem.

Socio-economic factors of the family and the oral health of the care-

taker are closely associated with the oral health and the oral health habits of the

child (89). No differences in educational level of the parents or in their dental

health could be detected between parents of the cases and their controls in Paper

ІІ. Based on this finding, there must be other reasons that explain the increased

caries experience in children with complex CHD.

Saliva plays a key role in the biological interaction between many

medical conditions and oral health related either directly, as in 22q11 and ecto-

dermal dysplasia, with a reduced salivary secretion (90, 91) or due to effects of

pharmacological treatment (92, 93). Medication-induced xerostomia has been

considered as a caries-risk factor in CHD children (94). Paper IV showed that

reduced salivary secretion could be a caries-risk factor in children on heart

failure medication. It is therefore possible that some participants had a reduced

salivary flow in Paper I and this may contribute to the explanation of the high

caries experience in children with complex CHD. Use of antibiotics during early

childhood has been associated with higher MS levels in children aged 5 to 12

years (95), and it is a clinical experience that antibiotics are used more fre-

quently among children with heart disease than healthy children but higher MS

levels has not been shown earlier (48, 96) or in Paper IV. Paper IV showed that

MS constituted a non-significantly higher proportion of the TVC in the study

group and this fit into the theory that a differentiation towards aciduric

microorganisms in the oral ecology precedes dental caries (34).

44

A novel finding was the strong correlation between digoxin

medication and caries experience in Paper I. Sucrose is added to the syrup to

disguise unpleasant taste and thereby facilitate compliance. Sucrose-containing

medicines are often given together with diuretics that can reduce salivary

secretion (68), which add to the cariogenic challenge. Sugars in medicines cause

a pH drop in the oral biofilm as a result of their fermentation in acid-producing

bacteria (23, 43). Additionally, acids in medicines may help to prolong the pH

drop after a sugar challenge. The clinical effects of the low pH, titratable acidity,

and effect on dental hard tissues shown in Paper V can only be speculated on as

data were obtained in vitro. It is, however, clear that some pharmaceutical

preparations commonly used in paediatric cardiology in Sweden have a low

endogenous pH and a potential to dissolve dental hard tissues. The erosive

potential depends on the intimate interplay between chemical factors like

endogenous pH and titratable acidity; biological factors such as the properties of

the saliva; and behavioural factors like oral hygiene, vomiting, and frequency of

medication (97). If this finding is taken together with the fact that these

medicines may be given together with Lanoxin® (digoxin), which contains

sucrose and some of the patients suffer from medication-induced xerostomia, it

is clear that medication may pose a hazardous threat to the oral health in

children with complex CHD. These findings support the hypothesis that both

caries and erosions are possible outcomes in connection with the regular use of

pharmaceutical preparations (97). An assessment of the prevalence of erosions

was not the within the aim of this thesis, however. In a study on the erosive

potential of 97 medicines used regularly and long term by children, 57 % had an

endogenous pH below 5.5, and those used for the cardiovascular system had the

lowest mean endogenous pH, and it was 4.05 (98). Further, Neves et al (75) con-

cluded that several paediatric medicines showed high sugar concentration, pH

values below the critical value, and high titratable acidity values, all of which

increase the medicines' cariogenic and erosive potentials.

45

Ersin et al (99) studied oral and dental manifestations of young

asthmatics in relation to medication, severity, and duration of the condition. The

results of their study supported the hypothesis that factors related to asthmatic

condition and/or medication might increase the risk of caries due to the lower

salivary flow rate and pH in asthmatics. In addition, the duration of medication

and the duration of illness were shown to be risk factors for caries development

in asthmatic children. The authors concluded that asthmatic patients especially

in the younger age groups should receive intensive preventive care, including

oral hygiene instruction, dietary advice, and regular topical fluoride treatments.

Stensson et al (56) investigated preschool children with asthma and found a

higher caries frequency among asthmatic children. They pointed to the

importance of developing preventive dental programs for preschool children

with asthma and of developing collaboration between dental and medical care-

givers in relation to children with asthma. This is also applicable for children

with complex CHD.

Being born with a heart anomaly may, depending on the severity of

the CHD, cause a dramatic start in life for the affected child and the family.

Surgery may be performed directly after birth or within the first year of life and

be followed by several complementary surgeries. Multiple medications and long

periods of hospitalisation with frequent contacts with medical staff become the

part of everyday life to families with children affected with complex CHD.

Feeding problems are often seen during the first years of life. Vomiting is

common and to compensate for this, feeds are frequent and night meals are often

necessary to maintain energy intake at an acceptable level. Infections often last

for longer periods than in healthy children, with an increased need for drinking,

sometimes at night, when salivary protection is low (4). Brain injury is the most

significant complication of surgery for CHD (100). Neurodevelopmental out-

come, however, is influenced mostly by genetic co-morbidity and preoperative

neurological status (101). A systematic review of psychological adjustment and

46

quality of life after open-heart surgery for congenital heart disease concluded

that children with more severe heart defects, or those in need of future surgical

interventions and children with neurodevelopmental impairment are at particular

risk for maladjustment (102). It is clear that children with complex CHD,

particularly at early ages, should be considered as a group with special needs in

dentistry (103-105).

Paper III showed that parents of children with complex CHD did not

have the same satisfaction with the reception they received in dental care than

the healthy controls. Children with CHD had received sedation before operative

dental treatment significantly more often than healthy children, reflecting a

higher need of operative dental treatment. The CHD group had also received

more caries prevention (Paper I). Lowry et al (106) compared dental attitudes

knowledge and health practice between a CHD group and a matched control

group and found that 18 % of the children with CHD had not received dental

care. In a study on the provision of dental care for medically compromised

children, it was shown that dental practitioners had treated patients with CHD in

0 to 5 sessions in the past 5 years with an average of 2 patients for each

practitioner (107). Only 37 % felt confident in providing dental treatment for

children with cardiac disease, while 80 % of the respondents stated they would

benefit from further regular training. Jowet and Cabot (108) noted that many

dentists were not confident in treating children with CHD, which is in coherence

with data in Paper III that indicated that Swedish dentists are unsettled and

insecure in the dental treatment of children with heart disease. As the PDS does

not differ significantly from county to county, the results of the study are

considered applicable to Sweden in general. The findings should, however, be

generalized to the whole group of children with CHD as it was considered

difficult for the dentists to classify their CHD patients due to limited information

on medical background facts. This lack of experience regarding these children’s

medical conditions and pharmacological regimes is a cause of concern and

47

suggests a need for specialist dental care for these children. These data also

support the need for further education about dental treatment for groups of

medically compromised children (109).

The transition into adulthood has been a significant clinical concern

as the survival rate for adolescents with CHD increases. There is a continued

need to support and counsel adolescents to maintain their health-promoting

behaviour. Health promotion counselling for adolescents with CHD should

encourage improving lifestyle habits, including adequate physical exercise and

good oral hygiene (110).

Clinical perspectives

Except for the replacement of sucrose in Lanoxin® with a non-cariogenic

sweetener, factors that can be changed in a more health-promoting direction in

children with complex CHD are oral hygiene habits, fluoride exposure, and

sugar consumption.

In the clinical management of children with complex CHD, high-

caries-risk children should be identified as early as possible, which is possible if

a close cooperation between the paediatric cardiologist and paediatric dentist is

established. Early preventive care should be adjusted to the special needs of

children with CHD and an individual preventive program should be

implemented during the first year of life (49). This regime is supported by Gussy

et al who in their review on caries in early childhood found evidence that

potentially effective interventions should occur in the first 2 years of life of the

child at risk (27). An interdisciplinary approach integrating the professional

knowledge and skills may help to improve the results for the individual patient

(43, 107, 111, 112).

The paediatrician should facilitate referral to dental services and

emphasize the importance of good oral health. For high-caries-risk groups, it is

recommended that regular dental care is offered within clinics for specialized

48

paediatric dentistry (103, 104). Together with parents, a plan for dental care

should be established, and the responsibilities for dental care and for families

should be made clear. Individual need of antibiotics for prophylaxis for infective

endocarditis at invasive dental treatments should also be determined (1). Short

recall intervals should be offered until the caries-risk factors are eliminated.

Children on medication with sugar-containing syrups should be given extra

attention, and salivary secretion should be assessed in children on heart failure

medication. Tooth brushing using fluoridated toothpaste should be encouraged.

Based on individual needs, additional fluoride may be indicated and is suggested

to be administered based on caries risk and compliance (24). Parents should be

advised to avoid added sugar at meals. Today, there is poor knowledge of the

early feeding practice in children with CHD. We will obtain knowledge from a

running prospective study of dietary habits and colonisation of the oral

microflora from an early age in children with complex CHD.

A continuous issue for improving the oral health is the

accomplishment of education and training for both dental and medical health

care providers about oral health problems and their prevention in this new group

of patients (109, 113).

49

Conclusions

Children with complex CHD had a higher caries experience than healthy

age- and gender-matched controls.

Children with complex CHD on digoxin medication had a higher caries

experience than other children with complex CHD.

Children with complex CHD had received more caries prevention than

healthy controls.

Parents of children with complex CHD were less satisfied with the

reception and care they received in the dental service compared with the

parents of healthy children.

Swedish dentists had a different opinion regarding the provision of dental

treatment to children with CHD compared to the current situation.

Children on heart failure medication can have a low saliva secretion.

Some pharmaceutical preparations used on long-term basis in paediatric

cardiology may pose a hazardous threat to dental hard tissues due to their

acidity.

50

Populärvetenskaplig sammanfattning

Medfödda hjärtfel (CHD) är en av de vanligaste utvecklingsanomalierna hos barn och

förekommer hos ca 8-10 per 1000 levande födda barn. Med anledning av stora

framsteg inom barnkardiologin de senaste decennierna så överlever idag allt fler barn

som föds med komplexa CHD. Detta har inneburit att barn med CHD blivit en ny och

växande patientgrupp även inom tandvården. Den övergripande målsättningen med

denna avhandling var att kartlägga kariesförekomsten och potentiella

bakgrundsfaktorer hos barn med komplexa CHD.

I delarbete I undersöktes kariesförekomsten hos 41 barn med komplexa

CHD och en kontrollgrupp av friska ålders- och könsmatchade barn. Barnen med

komplexa CHD hade en ökad kariesförekomst i mjölktandsbettet. Barn med CHD som

medicinerade med digoxin hade en högre kariesförekomst än de hjärtbarn som inte

använde denna medicin. Barnen med CHD hade fått mer kariesprofylax i tandvården

än friska barn.

I delarbete II studerades föräldrars attityder till och erfarenheter av

omhändertagande av barn med CHD i tandvården. Trettiotre föräldrar till barn med

komplexa CHD jämfördes mot en matchad grupp av föräldrar till friska barn. Föräldrar

till friska barn var mer nöjda med omhändertagandet och bemötandet inom tandvården

än föräldrar till barn med CHD. Studien rekommenderar att barn med komplexa CHD

erhåller sin tandvård hos specialistkliniker för barntandvård särskilt de första

levnadsåren.

I delarbete III studerades attityder till och erfarenheter av tandvård för

barn med CHD bland 183 allmäntandläkare. En minoritet av de tillfrågade tandläkarna

hade erhållit någon kompletterande utbildning av tandvård för barn med CHD. Cirka

50 % av tandläkarna hade en eller flera patienter med CHD och majoriteten av dessa

hade noterat en ökad kariesförekomst hos dessa barn. Studien visade att tandvård för

barn med CHD utförs till största del av tandsköterskor, tandhygienister och

allmäntandläkare vilket avvek från tandläkarnas önskemål om hur tandvården skall

organiseras för barn med CHD.

Många barn med komplexa CHD måste medicinera över lång tid och vissa

mediciner kan minska salivflödet och därigenom bidra till att karies utvecklas.

Salivens egenskaper studerades hos 24 barn som hade hjärtsviktsmedicinering i

delarbete IV och jämfördes mot saliv från en frisk kontrollgrupp. Salivens

sekretionshastighet, buffringskapacitet, bakteriehalter samt elektrolytnivåer

undersöktes. Tjugonio % av barnen med hjärtsviktsmedicinering hade låg

salivsekretion jämfört med inget barn i kontrollgruppen. En slutsats är att barn med

hjärtsviktsmedicinering kan ha låg salivsekretion och det kan vara en riskfaktor för att

utveckla karies.

I delarbete V studerades 13 av de mest använda medicinerna vid CHD

med avseende på pH, buffring samt förmåga till att lösa mineral från tandvävnad. Sex

av medicinerna hade ett pH-värde som kan vara skadligt för tandsubstans. Det

konkluderades att några av de vanligast förekommande medicinerna inom svensk

barnkardiologi kan utgöra ett hot mot tandvävnad på grund av surhetsgraden och

förmågan att lösa ut mineral.

51

Acknowledgements

First I would like to express my sincere gratitude to all children and parents who

have participated in the studies. Further, I am so grateful to all you who have

helped and supported me and made it possible to for me to complete my thesis.

In particular, I would like to thank:

Associate Professor Christina Stecksén-Blicks, my principal supervisor, co-

author and Head of the Division of Paediatric Dentistry, Umeå University, for

introducing me to the field of scientific research. Thank you for generously

sharing your vast scientific knowledge and your never ending inspiration, your

endless support and for always believing in me. I am so grateful for having you

by my side during this journey and I am looking forward to further

collaboration.

Associate Professor Annika Rydberg, my co-supervisor and co-author for

introducing me to and guiding me in the world of paediatric cardiology. Thank

you for your great expertise, good advice, valuable comments and the

enthusiasm you bring me every time we meet.

Technical assistant Inger Sjöström, co-author in papers IV and V and my

supervisor in the laboratory. Without your outstanding advice and assistance

with the laboratory management this would not have been possible.

Sofia Asplund, Kristin Grahn, Charlotta Svanberg and Sara Wikström, co-

authors, for your cooperation with the data collection in Paper I and II.

Hjördis Olsson for excellent help and support with administrative problems and

academic logistics.

Staff at the Paediatric Cardiology Clinics at the University Hospital, Umeå and

at the Karolinska University Hospital, Stockholm, Sweden, for helpful

assistance. You do a tremendous job for all children with CHD.

Colleagues and workmates at the Department of Paediatric Dentistry in Uppsala,

Umeå and at Eastmaninstitutet, Stockholm, for support, encouragement and

friendship.

52

Margaret Grindefjord, Head of the Department of Paediatric Dentistry,

Eastmaninstitutet, Stockholm, for making it possible for me to finish my PhD-

studies studies within the scope of my work and for always being so supportive.

Dental nurses Lena Lif and Barbro Enocson, Eastmaninstitutet, Stockholm, for

your assistance in the data collection, encouragement and never-ending

positivism.

Leila Aghababa, my dear friend, colleague and the best of roommates. Thank

you for interesting discussions, tremendous support and delicious lunches.

My family and friends for great support, patience and encouragement.

Signe and Ingrid, my beloved little daughters. Thank you for brighten up my

day with all your laughter, hugs and sweet kisses.

Fredrik. Thank you for your never ending love, your great encouragement,

support and interest in my work. I love you.

These studies were supported by grants from the Swedish Heart-Children’s

Association (Hjärtebarnsfonden), the Patent Revenue Found for Dental

Prophylaxis and the County Council of Uppsala, Sweden.

53

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59

APPENDIX I. Questionnaires Paper II

CHD

Dental health information and advice Describe the dental health information and advice. The

information has been Very good

Good

Neither good nor poor

Poor

Very poor

The quantity of information has been Sufficient

Neither sufficient nor

insufficient

Insufficient

Does your child have siblings? Yes

No

Did you notice differences in dental health information

compared to your child’s healthy siblings? Yes, more extensive

Yes, more adjusted to existing

needs

No

Don´t know

When did you receive information and advice on oral

health? When the child was < 6 months

6 months – 1 year

1-3 years

> 3 years

From where did you receive the information and advice? Physician

Dentist

Dental hygienist

Found information on my own

Other source

Is it possible to follow the current advice? Yes, completely

Yes, partly

No, I am doubtful

No, not at all

Have you been informed that your child needs antibiotic

prophylaxis before invasive dental treatment? Yes

No

From where did you first receive information about

antibiotic prophylaxis? Physician

Dentist

Dental hygienist

Found information on my own

Other source

Does the current dental health information need to be

changed? Yes, a lot

Yes, some

No, not in need of change

No opinion

60

Dental care and service Describe the reception at the dental clinic Excellent

Satisfactory

Decent

Poor

Very poor

Are enough time provided during appointments at the

dental clinic? Yes, definitely

Yes, partially

Probably not

No, not at all

Have sedatives or general anesthesia been used for your

child? Never

1-2 occasions

3-4 occasions

>4 occasions

What was your experience of sedatives or general

anesthesia Excellent

Satisfactory

Decent

Poor

Very poor

Was local anesthesia used when teeth were filled? Always

Often

Sometimes

Never

Don´t know

What was your experience with respect to the

competence of the dental staff Very good

Good

Varying

Bad

Very bad

Do you believe the control intervals were adjusted to

meet the needs of your child? Gaps were to long

Sufficient

Too close

Don´t know

Children and parents

How would you describe your child’s dental health? No problems

Some problems

Large problems

How do you experience your child´s expectations before

a visit to the dental clinic? Positive

Neither positive nor negative

Negative

Don´t know

Does you or the other parent experience discomfort

before your own visits at the dental clinic? Always

Sometimes

Never

Don´t know

61

Dental health of mother No problems

Some problems

Large problems

Educational level of mother Nine years

12 years

University/college

Dental health of father No problems

Some problems

Large problems

Educational level of father Nine years

12 years

University/college

Your comments

62

Controls

Dental health information and advice Describe the information you received regarding oral

health care. The information has been Very good

Good

Neither good nor poor

Poor

Very poor

The quantity of information has been Sufficient

Neither sufficient nor

insufficient

Insufficient

When did you first receive information and advice on

oral health? When the child was < 6 months

6 months – 1 year

1-3 years

> 3 years

From where did you receive the information and advice? Physician

Dentist

Dental hygienist

Found information on my own

Other source

Is it possible to follow the current advice? Yes, completely

Yes, partly

No, I am doubtful

No, not at all

Does the current dental health information need to be

changed? Yes, a lot

Yes, some

No, not in need of change

No opinion

Dental care and service

Describe the reception at the dental clinic Excellent

Satisfactory

Decent

Poor

Very poor

Are enough time provided during the appointments at

the dental clinic? Yes, definitely

Yes, partially

Probably not

No, not at all

Have sedatives or general anesthesia been used for your

child? Never

1-2 occasions

3-4 occasions

>4 occasions

What was your experience of sedatives or general

anesthesia Excellent

Satisfactory

Decent

Poor

Very poor

63

Was local anesthesia used when teeth were filled? Always

Often

Sometimes

Never

Don´t know

What is your experience with respect to the competence

of the dental staff Very good

Good

Varying

Bad

Very bad

Do you believe the control intervals were adjusted to

meet the needs of your child? Gaps were to long

Sufficient

Too close

Don´t know

Children and parents

How would you describe your child’s dental health? No problems

Some problems

Large problems

How do you experience your child´s expectations before

a visit to the dental clinic? Positive

Neither positive nor negative

Negative

Don´t know

Does you or the other parent experience discomfort

before your own visits at the dental clinic? Always

Sometimes

Never

Don´t know

Dental health of mother No problems

Some problems

Large problems

Educational level of mother Nine years

12 years

University/college

Dental health of father No problems

Some problems

Large problems

Educational level of father Nine years

12 years

University/college

Your comments

64

APPENDIX II. Questionnaire Paper III

1. How much of your clinical time do you practice dentistry

for children? 0 %

0-24 %

25-49 %

50-74 %

75-100 %

2. Have you received any education/information regarding

dental care of children with heart disease except that during

the graduate training?

Yes

No

I don´t know

3. Has any of your child patients a heart disease? Yes, one or several

No, no one

I don´t know

I don´t treat children

If response alternative 2-4 in question 3, please go to question

12

4. Do you know the child’s/children’s heart diagnosis? Yes

No

5. Do you know if the any of the child/children has any heart

medication? Yes

No

6. Has your child patient/s with heart disease display a caries

experience? Yes

No

I don´t know

7. Do you know the name/s of the child’s/children’s

physician/s? Yes

No

8. Have you been in contact with the child’s/children’s

physician/s? Yes

No

If no please go to question 11

9. If yes in question 8, what was your opinion of the

cooperation? Positive

Negative

Neither positive nor negative

10. What is your experience on providing dental treatment for

children with heart disease? More than one alternative may be

chosen.

No special difficulties

Odontological difficulties

Medical difficulties

Insecurity regarding the

child´s medical condition

11. How is the dental treatment and care of children with heart

disease arranged in your clinic? The same as for healthy

children

More caries prevention

Longer visits

Shorter recall intervals

No opinion

12. Do you know if any of the pharmaceutical preparations

taken by children with heart disease can increase the caries

risk?

Yes

No

No opinion

65

13. Have you received clear cut information regarding which

heart diagnoses that should be provided with antibiotic

prophylaxis before invasive dental treatment?

Yes

No

No opinion

14. Who in the dental team perform the major part of dental

care for children with heart disease? Dental nurse

Dental hygienist

General dentists

Dentists with special training

Specialists in paediatric

dentistry

15. What is your opinion on who in the dental team that

should perform the major part of the dental care for this group

of children?

Dental nurse

Dental hygienist

General dentists

Dentists with special training

Specialists in paediatric

dentistry

16. Your gender? Male

Female

17. Year of your dental graduation?

18. University?

Your comments