Dominique Declerck

Factors associated with prevalence and severity of caries experience in preschool children.

OBJECTIVES The aim of the present study was to examine the prevalence and severity of caries experience in the primary dentition of preschool children and to assess the association of disease distribution with oral hygiene levels, reported oral health behaviours and socio-demographic factors. METHODS Study samples comprised 1250 3-year-old and 1283 5-year-old pre-school children from four distinct geographical areas in Flanders. Information on oral hygiene and dietary habits, oral health behaviours and socio-demographic variables was collected using questionnaires completed by the parents. Clinical examinations were performed using standardized criteria. Caries experience was recorded at the level of cavitation (d(3) level). Simple as well as multivariable logistic regression analyses were performed in order to identify factors associated with prevalence and severity of caries experience. RESULTS Visible plaque was present in 31% of 3-year-olds and 37% of 5-year-olds. In 3-year-olds, 7% presented with caries experience while this was the case in 31% of 5-year-olds. Multivariable logistic regression revealed significant associations, in 3-year-olds, of caries experience with presence of dental plaque (OR = 7.93; 95% CI: 2.56-24.55) and reported consumption of sugared drinks at night (OR = 7.96; 95% CI: 1.57-40.51). In 5-year-olds, significant associations were seen with age (OR = 7.79; 95% CI: 2.38-25.43), gender (OR = 0.37 with 95% CI: 0.19-0.71 for girls), presence of visible dental plaque (OR = 3.36; 95% CI: 1.64-6.89) and reported habit of having sugar-containing drinks in between meals (OR = 2.60 with 95% CI: 1.16-5.84 and OR = 3.18 with 95% CI: 1.39-7.28, respectively for 1x/day and > 1x/day versus not every day). In 5-year-olds with caries experience (30.8% of total sample), the severity of disease was further analysed (d(3)mft between 1 and 4 versus d(3)mft 5 or higher). Multivariable analyses showed a significant association with gender [girls more likely to have higher disease levels; OR = 4.67 (95% CI: 1.65-13.21)] and with presence of plaque (OR = 3.91 with 95% CI: 1.23-12.42). CONCLUSIONS Presence of visible plaque accumulation and reported consumption of sugared drinks were associated with prevalence of caries experience in Flemish preschool children. Severity of disease was associated with gender and with presence of plaque. Results underline the importance of plaque control and diet management from very young age on.

The Value of a Baseline Caries Risk Assessment Model in the Primary Dentition for the Prediction of Caries Incidence in the Permanent Dentition

To establish a reliable screening method for caries prediction and to identify predominant risk factors, this study tested whether a cross–sectional caries risk model assessed at age 7 could be used to predict future caries onset in the permanent first molars at age 10 in 3,303 children born in 1989. As prediction variables, assessing the believed risk, baseline data at age 7 on oral health status, oral hygiene level, oral health behaviour and sociodemographic factors were used. The real risk, based on data collected for the first permanent molars during the follow–up, was assessed by different approaches. Cumulative incidence during the 3–year observation period was 31.6%, ranging from 22.4% in the believed low–risk group to 43.2% in the believed high–risk group. A stepwise logistic regression analysis was performed with net caries increment as outcome measure, adjusted for the real time at risk, using eruption times. Baseline dmfs and occlusal and buccal plaque indices were highly significant for having a high caries increment in permanent first molars with respective odds ratios of 1.07, 1.43 and 1.35. Brushing less than once a day and the daily use of sugar–containing drinks between meals were confirmed as risk factors (OR 2.43 and 1.25, respectively). The logistic regression analysis provided a sensitivity of 59–66% and a specificity of 65.7–72.8%, which indicates that the risk marker did not have an important predictive power. None of the socio–demographic and behavioural variables had enough predictive power at community level to be useful for identifying caries susceptible children. Even the power of dmfs at baseline must be considered modest.

The zero-inflated negative binomial regression model with correction for misclassification: an example in caries research

Zero-inflated models for count data are becoming quite popular nowadays and are found in many application areas, such as medicine, economics, biology, sociology and so on. However, in practice these counts are often prone to measurement error which in this case boils down to misclassification. Methods to deal with misclassification of counts have been suggested recently, but only for the binomial model and the Poisson model. Here we look at a more complex model, that is, the zero-inflated negative binomial, and illustrate how correction for misclassification can be achieved. Our approach is illustrated on the dmft-index which is a popular measure for caries experience in caries research. An extra problem was the fact that several dental examiners were involved in scoring caries experience. Using our example, we illustrate how a non-differential misclassification process for each examiner can lead to differential misclassification overall.

Effect of Caries Experience in Primary Molars on Cavity Formation in the Adjacent Permanent First Molar

This study sought to address the influence of a sound versus affected first and/or second deciduous molar on the incidence of visible caries experience in the adjacent permanent first molar. Clinical and questionnaire data were obtained from a 6-year prospective oral health screening project in Flanders, Belgium (Signal-Tandmobiel® project), where 4,468 children (born in 1989) were examined annually during their primary school time. A multiple survival model allowing for dependent data with possible censoring was applied. The impact of timing of tooth emergence (determining the period at risk), gender, presence of sealants and reported oral hygiene habits was also considered. Cavity formation in permanent first molars was clearly influenced by the status of the adjacent primary molars;the effect of the second deciduous molar was most pronounced. Moreover, if both deciduous molars experienced caries and the child presented with poor oral hygiene, a peak in cavity formation of the permanent first molar 1–2 years after emergence was noticed. On the other hand, if a child presented with good oral hygiene, no peak was observed;caries risk increased slightly over time. No significant benefit from restoring primary molars could be demonstrated, possibly because of methodological limitations.

Parental smoking behavior and caries experience in preschool children

OBJECTIVES The study aimed to explore the association between parental smoking behavior and caries experience in young children, taking into account the socioeconomic status and oral health-related behavior. METHODS Cross-sectional data from 1250 3-year-old and 1283 5-year-old children from four geographical areas in Flanders (Belgium) were analyzed. Children were examined at school by trained dentist-examiners, using standard criteria and calibrated examination methodology. Data on oral hygiene and dietary habits, oral health behavior, sociodemographic variables, and parental smoking behavior were obtained through structured questionnaires, completed by the parents. RESULTS Visible caries experience (i.e. d(3)mft > 0) was seen in 7% of 3-year olds and 31% of 5-year olds. In both age groups, 30% of the parents reported smoking behavior. Univariable logistic regression analysis with caries prevalence as the dependent variable, revealed that parental smoking was a significant independent variable. After controlling for age, gender, sociodemographic characteristics, oral hygiene, and dietary habits, the effect of family smoking status was no longer significant in 3-year-old children (OR = 1.98; 95% CI: 0.68-5.76). In 5-year olds the significant relationship between parental smoking behavior and caries experience persisted after adjusting for the other evaluated variables (OR = 3.36; 95% CI: 1.49-7.58). CONCLUSION The results of this study illustrate the existence of a significant association between parental smoking behavior and caries experience in 5-year-old children.

Prevalence and Determinants of Enamel Fluorosis in Flemish Schoolchildren

As part of an epidemiological study on the oral health of Flemish schoolchildren, fluoride use was studied together with risk factors (medical history, tap water fluoride concentration, use of fluoride supplements, toothpaste and brushing habits). Fluorosis was scored according to the Thylstrup-Fejerskov index (TFI) in children aged 11 years (4,128 children examined). Explanatory variables were recorded yearly, starting at the age of 7. Earliest toothpaste use was reported at the age of 1. By age 7, 99.7% of the children reported the use of toothpaste (90% fluoride-containing), but only 13.9% reported using a pea-sized amount. At age 7, 66% of the children had received systemic fluoride supplements during at least part of their childhood. At 11 years, 92% of the children used a fluoride-containing toothpaste and 6% still received systemic fluoride supplements. Fluorosis was present in about 10% of all the children examined, mainly TFI score 1 (7.3% in upper central incisors). Logistic regression established tooth brushing frequency and fluoride supplement use, in addition to tap water fluoride concentrations above 0.7 mg/l, as significant risk factors when the presence of fluorosis on at least one tooth was used as outcome variable. Children having fluorosis had a lower risk of caries, both in the primary (median dmft 1, range 0–10 vs. 2, range 0–12) and permanent dentition (median DMFT 0, range 0–5 vs. 0, range 0–11).

Dental caries, gingival health, and oral hygiene of long term survivors of paediatric malignant diseases.

Fifty two children who had had cancer and been treated with chemotherapy, and who were long term event free, were examined for caries prevalence, gingival health, and oral hygiene and compared with a control group. A higher dental caries prevalence for the 14-17 year age group was noted. The restorative index was significantly lower in the age group 10-13. There were no significant differences in gingival index, plaque index, or toothbrushing frequency. It is concluded that these patients should be considered as at high risk for caries after cancer treatment. Professional dental follow up should be integrated in the medical follow up.

Caries pattern and oral health habits in 2- to 6-year-old children exhibiting differing levels of caries

Abstract The aim of the present study was to describe in detail the distribution of caries lesions among tooth types and surfaces in the primary dentition of young children with different levels of disease. A total of 125 children (between 2 and 6 years old) attending the pediatric dental clinic of the University Hospital of Leuven was allocated to three groups based on their caries experience: dmft=1–5 formed the low caries experience group (LC, n=27), dmft=6–9 the moderate caries experience group (MC, n=61) and those with dmft>=10 the high caries experience group (HC, n=37). Caries experience (at patient level, tooth and tooth surface level) and oral hygiene were evaluated. Oral health habits were recorded using a questionnaire (completed by parents). Caries lesions were not evenly distributed among different tooth types. Teeth most frequently affected were lower (first and second) primary molars. Primary incisors were rarely found to be carious. The distribution of the lesions followed a comparable pattern, irrespective of the disease level of the child. Decay on primary canines and buccal/lingual surfaces of primary molars was strongly indicative of a high caries experience. There was a clear link with reported oral hygiene habits and the use of a pacifier and baby bottle with sugared content.

Influence of Anticoagulation on Blood Loss Following Dental Extractions

The coagulation activity level at which oral surgical procedures can be performed in anticoagulated patients without triggering bleeding complications and without enhancing the risk of developing thrombo-embolic events remains controversial. The objective of the present study was to evaluate blood loss following dental extractions at different levels of anticoagulation and to determine its effect on wound closure rates. Blood loss was measured following the removal of four front teeth in warfarinized rabbits. Immediate blood loss was evaluated by determining the tooth socket bleeding times and by using a technique based on hemoglobin determinations. Long-term blood loss was assessed by comparison of labeled red-blood-cell disappearance curves. The results showed that blood loss following dental extractions was significantly greater in animals anticoagulated at a therapeutic level than in non-anticoagulated control animals. Determination of blood loss at different levels of anticoagulation clearly demonstrated that complete correction of the coagulation activity was unnecessary. Partial correction (INR values of 1.6-1.8) allowed extractions to be performed without extensive blood loss. With this technique of partial correction, the period of interruption of the anticoagulation could be kept very short, and the risk of postoperative bleeding complications was minimal. Wound closure rates were negatively influenced in anticoagulated animals.

An overview of methods for interval-censored data with an emphasis on applications in dentistry.

Interval-censored time-to-event data occur in many medical areas, with dentistry or AIDS research being typical representatives. This article reviews methods for the analysis of such data, with an emphasis on the use of the accelerated failure time (AFT) model. A flexible AFT model (avoiding parametric assumptions on the distribution of the error term) is described in greater detail and is used to solve a typical dental question in a longitudinal oral health study.