[Caries prevention in historical perspective. Social factors]. / Serie: Cariëspreventie in historisch perspectief. Maatschappelijke factoren.

At the beginning of the twentieth century, children from poor families had less caries than children from affluent families. Later this changed: as the socio-economic status of the parents was higher, the children had less dental caries. The same relationship between socio-economic status and caries prevalence was later evident in adults. Throughout the twentieth century, in individuals with a low socio-economic status more teeth were extracted than in individuals with a high socio-economic status. At the end of the twentieth century, oral health in general was much better than at the beginning. That change is partly due to increased prosperity, increasing attention to oral hygiene, the introduction of fluoride toothpaste and the strong increase in the number of professionals in oral care. Increased knowledge of the causes and prevention of caries also played a role, if a less prominent one.

[Series: Caries prevention in historical perspective. Education]. / Serie: Cariëspreventie in historisch perspectief. Voorlichting.

In the Netherlands, since the end of the nineteenth century, information has been given to the public about possible ways to prevent dental caries. This happened in the dental offices, in health centres where the parents of young children received advice, and in schools. From 1968 until the mid-1980s, large-scale information campaigns were organised in various municipalities and regions. The Ivory Cross, a Dutch society for oral health education, has been providing information on oral health and supporting the provision of information for, among others, dentists and dental hygienists by offering educational material. The understanding of the phenomenon 'information' has changed during the past century. By applying new insights, there is an increased chance to prevent caries by providing information.

[Series: Caries prevention in historical perspective. Early treatment of carious lesions]. / Serie: Cariëspreventie in historisch perspectief. Vroegtijdige behandeling cariëslaesies.

In the Dutch Journal of Dentistry the opinion is often expressed that treatment of carious deciduous teeth is necessary to reduce the risk of dental caries in the permanent teeth. It is clear that early restorative treatment of caries lesions can contribute to the preservation of teeth. The question is whether such a treatment also has a primary preventive impact on other not yet affected teeth. Results of epidemiological research carried out in the period 1960-1980 do not support the view that it does. To combat the 'disease' caries in children restoration of carious teeth alone will not suffice. Professional oral care in young children should be focused primarily on removing the causes of dental caries by insisting on improvements in hygiene and diet.

[Series: Caries prevention in historical perspective. Fluoride]. / Serie: Cariëspreventie in historisch perspectief. Fluoride.

Shortly after the Second World War it became known in the Netherlands that fluoride can contribute to the prevention of dental caries. As to how this effect was achieved, opinions differed. Initially, the dominant the view was that fluoride had to be absorbed into the enamel and dentine during tooth formation to make the teeth resistant to caries. Later it was discovered that decalcification of the enamel is inhibited if fluoride is present in the dental plaque. While in the beginning water fluoridation was considered to be the most effective measure to prevent caries, the current position is that tooth brushing with fluoride toothpaste plays the most important role in caries prevention.

[Series: Caries prevention in a historical perspective. Food]. / Serie: Cariëspreventie in historisch perspectief. Voeding.

Different ideas on the impact of diet on the occurrence of dental caries that have been of influence during the last 125 years are discussed. The initial premise was that deficits in calcium and vitamins during the formation phase of the teeth were the cause of their high caries susceptibility. That idea has been abandoned. The frequency with which someone eats or drinks after the eruption of the teeth and the avoidance of quickly degradable carbohydrates in the diet now appear to be the most important factors for the development of caries lesions. The question whether nutrition education is still needed now that caries can be prevented by cleaning teeth with fluoride toothpaste, is discussed.

[Caries prevention in historical perspective. Oral hygiene]. / Serie: Cariëspreventie in historisch perspectief. Mondhygiëne.

Since the beginning of the twentieth century, the ability to prevent caries has greatly improved. This is due to both increased knowledge about the origin of dental caries, and to the availability of effective aids to oral hygiene, such as fluoride toothpaste. The effect of oral hygiene on the general population has also risen because more and more people brush their teeth.

[Research for sale. Risks of contract research]. / Onderzoek tegen betaling. Risico's van contractonderzoek.

In recent years it has become more and more apparent that contract research not only has obvious advantages, but risks also. It has been found that occasionally investigators are pressed to modify the conclusions of their work if the conclusions conflict with the interests of the funding organisation. In other cases, the publication of results is obstructed or retarded. Not only commercial companies, but also governmental and other non-profit institutions are guilty of these practices. If research findings are not presented or are presented in an altered form, not only will science be obstructed, but also the entire society will suffer. The responsibility for preventing these practices not only falls with the investigators, but also with their research institutions and the funding organisations.

Selective association of multiple sclerosis with infectious mononucleosis.

Previous studies have suggested an association between multiple sclerosis (MS) and infectious mononucleosis (IM) but data on the exact strength of this association or its selectivity have been conflicting. In this study we have evaluated the association between MS and a variety of common childhood infections and afflictions in a large population-based case-control study involving 2,877 MS cases and 2,673 controls in the Netherlands. We examined the frequency of different common infections and afflictions before the age of 25 and the age at which they occurred, using a self-administered questionnaire. The Odds ratios (ORs) for the occurrence of a variety of clinically manifest common childhood infections including rubella, measles, chicken pox and mumps before the age of 25 for MS cases versus controls ranged between 1.14 and 1.42, values similar to those for irrelevant probe variables used to reveal recall bias. In contrast, the OR for clinically manifest IM in MS cases versus controls, corrected for demographic variables, was 2.22 (95% confidence interval 1.73 - 2.86; P < 0.001). The average age of onset of IM in the population of MS cases (16.5 years) did not differ from controls (16.8 years). Our data confirm previous much smaller studies to show that the risk for MS is significantly enhanced by prior IM, and extend those previous data by showing that this association is far stronger than with other common childhood infections or afflictions.

Caries pattern in primary molars in Dutch 5-year-old children.

AIM: The aim of this study was to investigate the difference in caries prevalence based on quadrant dmfs data between first and second primary molars in 5-year-old Dutch children. STUDY DESIGN: Cross-sectional observational study. METHODS AND STATISTICS: For this study 692 children, all insured by a "Health Insurance Fund", living in one of four selected cities in The Netherlands were asked to participate in the study. From the original cohort 435 children (49% girls) participated. Clinical examinations were performed and only carious lesions with involvement of the dentine were reported. Lesions on the occlusal, buccal, palatinal/lingual, mesial and distal surfaces as well as lesions in buccal and palatinal pits and fissures were reported separately. No radiographs were taken. Systematic differences in dmfs between first and second molars in the same quadrant of each primary dentition were tested with the Wilcoxon signed rank test. RESULTS: Second primary molars, even after correction for caries in pits and buccal/palatinal fissures, had a statistically significant higher total dmfs than the first primary molars. The differences were mainly found on the occlusal surfaces. On proximal surfaces, the first primary molars had significant more caries than the second primary molars. The d-component constituted the major part of the caries index. CONCLUSIONS: Second primary molars, corrected for decay in the pits and buccal/palatinal fissures of this molar, are more affected by caries than first primary molars and that the differences in caries prevalence are the largest on the occlusal surface. The specific site of the caries found suggests that developmental disturbances in second primary molars may attribute to their prevalence.

[Oral health care in nursing and old people's homes and institutions for the mentally handicapped]. / Mondzorg in verpleeg- en verzorgingshuizen en instellingen voor verstandelijk gehandicapten.

Staff members and residents of nursing homes and old people's homes were interviewed about the facilities and provision of oral health care. Clinical examinations were performed to obtain data about the oral health status of the institutionalised elderly. Results show that in most cases the oral health care facilities were insufficient to give care to persons with natural teeth. Of the edentulous elderly 43% reported that the retention of the lower denture was insufficient.

The oral health status of dentate patients with chronic renal failure undergoing dialysis therapy.

OBJECTIVE: The aim of this study was to compare the oral health status of chronic renal failure (CRF) patients on renal replacement therapy with a matched reference population. DESIGN: Cross-sectional study. SUBJECTS: Forty-two dentate CRF patients--aged 25-52 years old--were matched with a reference group of 808 dentate subjects. METHODS: The oral health was assessed using decayed missing filled (DMF) indices, simplified oral hygiene index and periodontal status. An oral health questionnaire was used to assess self-reported dental problems. Student t-tests and chi-square tests were performed to compare the CRF patients with the controls. RESULTS: All index-scores in the CRF patients were comparable with the controls except for number of teeth covered with calculus that was significantly higher (P < 0.05) in CRF patients (4.1 +/- 2.6) than in controls (3.0 +/- 2.9). The self-reported oral health questionnaire revealed a trend for increased temporomandibular complaints in CRF patients (16.7%vs 5.7% in controls; P = 0.06) as well as bad taste (31.0%vs 6.8% in controls, P = 0.08). CONCLUSIONS: For most dental aspects, the oral health of CRF patients is comparable with controls.

[The effect of fluoride application in adolescents of lower socio-economic status]. / Het effect van de fluorideapplicatie bij jongeren met een lagere sociaal-economische status.

Purpose was to study the effect of professionally applied topical fluoride on oral health status on the population level in adolescents with lower socio-economic status. Adolescents attending dental clinics where professional fluoride application is a routine procedure (high-fluoride group) were compared to adolescents from other clinics (low-fluoride group). The study consisted of a questionnaire, a clinical examination with two bitewing radiographs. X-rays showed no statistically significant differences in the number of DS, FS or DFS. Clinically, there were no statistically significant differences in the number of FS or in the number of DFS. The low-fluoride group had a statistically significant higher number of DS than the high-fluoride group. The results suggest that professionally applied fluoride has a limited effect on caries and treatment experience in a population. These results justify a randomised clinical trial to study the effectiveness of professionally applied topical fluorides.

Approximal caries increment: a three-year longitudinal radiographic study.

AIM: To determine, for different age groups, the approximal caries increment in a three-year longitudinal retrospective study and to investigate the relationship between the caries increment and self-reported measures for oral health behaviour, dental knowledge and attitude (cynicism, health concern and motivation). SUBJECTS: 14, 17, 20 and 23-year-olds, who participated in a clinical epidemiological survey. Bitewings were taken of approximately 52% of the participants. Longitudinally, three cohorts were followed radiographically for three years. The self-reported measures were derived from questionnaires with sufficient reliability. RESULTS: For all participants, on average, 3.7 enamel lesions and 1.2 dentine lesions were found. The number of sound surfaces, adequate restorations and the D1FS score showed significant differences over a three-year period, for all age groups. Stepwise regression analysis showed that for the explanation of the change in number of sound surfaces, number of enamel lesions and D1S between the age of 17 and 20, the variable 'health concern' contributed significantly to the regression. The change in D3FS score was explained by the variable 'behaviour', while the change in D1Fs score was explained by both 'behaviour' and 'health concern'. Neither of the dental variables, 'dental knowledge' or 'motivation' contributed significantly. For the ages 14-17 and 20-23 no significant contributions were found. CONCLUSIONS: A considerable caries increment was found in this three-year retrospective radiographic study, which was not related to dental knowledge and motivation, and only for one age group (17-20) to oral health behaviour and health concern.

Effect of the routine professional application of topical fluoride on caries and treatment experience in adolescents of low socio-economic status in the Netherlands.

The purpose of this study was to study the effect of professionally applied topical fluoride on oral health status at the population level in adolescents with low socio-economic status. Adolescents attending dental clinics where professional fluoride application was a routine procedure (high-fluoride group) were compared to adolescents from other clinics (low-fluoride group). The study consisted of a questionnaire, a clinical examination and two bitewing radiographs. X-rays showed no statistically significant differences in the number of DS, FS or DFS. Clinically, there were no statistically significant differences in the number of FS or in the number of DFS. The low-fluoride group had a statistically significant higher number of DS than the high-fluoride group. The results indicate that professionally applied fluoride has no effect on caries and treatment experience in a population. These results justify a randomized clinical trial on a population level to study the effectiveness of professionally applied topical fluorides.

[Dental caries in the Netherlands at the turn of the century]. / Tandcariës in Nederland rond de eeuwwisseling.

In this paper an overview is given of recent studies concerning the prevalence of dental caries in children and adults in The Netherlands. Compared to the oral status in the past, the prevalence in children is still low. The decrease of caries is now also visible in adults up to the age of 45 years. The caries experience of people in older age categories is still high. A significant relationship was found between caries prevalence in children and level of school education of the mother and between caries experience of adults and their level of school education. A relatively high caries prevalence was found in children whose mothers were born in Turkey or Morocco. On the other hand, adults born in these countries had a lower caries experience than native Dutch adults.

[Oral health care in young people insured by a health insurance fund 3. Dental attendance and oral hygiene habits in the Netherlands between 1987 and 1999]. / Tandheelkundige verzorging jeugdige ziekenfondsverzekerden. 3. Tandartsbezoek en mondhygiënisch gedrag tussen 1987 en 1999.

In 1987, 1993 and 1999 an epidemiological study on oral health was performed in youngsters aged 5, 11, 17 or 23 years, in whom oral health care was covered by a health insurance fund. To obtain data on dental attendance, oral hygiene habits and the use of fluoride tablets questionnaires were used; data on the prevalence of dental plaque and calculus was obtained by clinical observations. The percentage of 5-year-olds attending a dentist at least once a year decreased between 1987 and 1999. In 23-year-olds a shift was observed from an attending frequency of twice to once a year, probably as a result of a change of the regulations of the Health Insurance Funds in 1995. The questionnaire data show that frequency of tooth brushing of 5- and 11-year-old children increased between 1987 and 1999. However, this change did not result in a lower prevalence of dental plaque. In the 17- and 23-year-olds a significant decrease of the prevalence of calculus was found. The use of fluoride tablets by children 5 year of age declined between 1987 and 1999. As the Dutch Society for Oral Health Education, Ivoren Kruis (Ivory Cross), altered the recommendations on the use of these tablets, this change could be expected.

[Oral health care in young people insured by a health insurance fund. 2. Prevalence and treatment of malocclusions in the Netherlands between 1987-1999]. / Tandheelkundige verzorging jeugdige ziekenfondsverzekerden. 2. Prevalentie en behandeling van orthodontische afwijkingen tussen 1987 en 1999.

In this paper data are presented about malposition of teeth in 5-, 11-, 17- and 23-year-olds in the time period between 1987-1999. Furthermore, results are shown of a longitudinal study in youngsters 11-17-years of age of whom some were and others were not treated orthodontically. Between 1987 and 1999, the percentage of youngsters who received orthodontic treatment increased from 23% to 40%. In the same time period the percentage of youngsters 17- and 23-year-olds with a malposition of teeth decreased. In youngsters involved in the longitudinal study and treated orthodontically, a strong improvement of the tooth position was found between the age of 11 and 17. Such an improvement did not appear in the non-treated group. The outcomes are considered as an indication that orthodontic treatments have positive effects on individual and on population level.

[Dental care for young people insured by health insurance fund 1. Prevalence and treatment of dental caries between 1987 and 1999]. / Tandheelkundige verzorging jugdige ziekenfondsverzekerden. 1. Prevalentie en behandeling van cariës tussen 1987 en 1999.

In 1987, 1993 and 1999 an epidemiological study was performed on oral health in youngsters, aged 5, 11, 17 or 23 years, in whom oral health care was covered by a health insurance fund. The prevalence of caries in the deciduous teeth of the 5-year-olds (examined without radiographs) did not change significantly between 1987 and 1999. Only a small proportion of dmfs was filled. Caries prevalence in permanent teeth of the 11-, 17- and 23-year olds decreased significantly. The number of filled surfaces decreased also. Between 1993 and 1999 the number of clinically found DS increased. However, this rise in dentinal caries lesions was not confirmed by similar findings in a simultaneous performed study with bitewing radiographs.

[Clinical underestimation of the prevalence of approximal dentin lesions and inadequate restorations]. / Klinische onderschatting van de prevalentie van approximale dentinelaesies en inadequate restauraties.

The aim of this study was to determine the additional diagnostic value of bitewing radiographs compared to clinical examination, with respect to the presence of dentine lesions and inadequate restorations for different age groups. Subjects were 14-, 17-, 20-, 23-years-old, or were in the age groups of 25-34 and 35-54 years, who participated in 2 clinical epidemiological surveys. After obtaining informed consent, bitewing radiographs were made of approximately 25% of the participants (n = 663). The extra diagnostic yield of the bitewing radiographs varied between a factor 1.6 and 7.2 for approximal dentine caries diagnosis of untreated surfaces, and between 2.3 and 5.9 for inadequate restorations. In conclusion, a considerable increase in the numbers of approximal dentinal lesions and inadequate restorations for all age groups was found.

The value of salivary bacterial counts as a supplement to past caries experience as caries predictor in children.

This study aimed to determine whether salivary mutans streptococci and lactobacilli counts could add any value to a combination of caries experience variables that was recently presented for the prediction of caries. Sixty-nine children at the age of 7.5 yr participated in this longitudinal study. Microbiological data were obtained at the ages of 7.5, 9.5 and 11.5 yr and caries data at the ages of 7.5. 9.5. 11.5, 13.5 and 15.5 yr. Spearman's correlation coefficients were computed, and forward multiple regression analyses were carried out using bacterial counts and caries experience parameters as explanatory variables and caries increment as a dependent variable. The explained variance (adjusted R2 value) was the measure used to assess the additional value of bacterial counts to the caries predictive potential of the combined parameters of the past caries experience. Correlation coefficients between bacterial counts and 4-yr caries increment were from 0.22 tip to 0.54. In all cases, the simultaneous streptococcus mutans-lactobacilli counts showed a statistically non-significant additional adjusted R2 value of <0.06. The results do not lend support to the concept that these salivary bacterial counts are useful additional caries predictors for the mixed dentition, when a combination of caries experience parameters is used.