[Non-restorative cavity treatment: from guidelines to the practice]. / Niet-restauratieve caviteitsbehandeling: van richtlijn naar de praktijk.

The new KIMO guidelines 'Oral Health Care for Children' approach caries as a behavioural related disease and unequivocally assign priority to causal caries treatment, emphasising lifestyle and behavioural changes. The 5-step concept of non-restorative caries treatment (NRCT) is recommended as treatment of choice for cavitated dentine lesions in primary dentition. Communicative aspects of NRCT are supported by limited technical interventions, for the purpose of effective oral care. A balance between aetiological and symptomatic treatment is sought for each child individually, in close cooperation with the parents. Technical aspects per tooth range from limited interventions like making cavities accessible for brushing, applying fluoride varnish or SDF, covering the cavity with a layer of glass ionomer cement to treatment like ART restoration or the Hall technique, in cases of necessity. Lifestyle changes lead to sustainable treatment results and enhance the quality of life of the child or young person.

[Neurotoxicity of sedatives and anaesthetics in young children]. / Neurotoxiciteit van sedativa en anesthetica bij jonge kinderen.

Many histological studies, animal experiments and also human studies during the past 30 years have proven that the use of general anaesthesia in young children under the age of four can have a permanent effect on the brain, which is still developing, and can therefore cause learning and/or behaviour problems later in life. This knowledge has to be taken seriously into account in the discussion with parents whether general anaesthesia is really necessary for the treatment of Early Childhood Caries in very young children.

Comparison of proximal contacts of Class II resin composite restorations in vitro.

This study investigated the tightness of the proximal contact when placing posterior resin composite restorations with circumferential and sectional matrix systems in an in vitro model using a special measuring device (Tooth Pressure Meter). A manikin model was used with an artificial first molar in which an MO-preparation was ground, simulating the clinical situation of an amalgam replacement. This preparation was duplicated, resulting in 160 identically prepared teeth. These teeth were divided into 8 groups (n=20). In 2 groups, circumferential matrix bands (flat or contoured) in a Tofflemire retainer were applied. In the remaining 6 groups, 3 different separation rings were combined with 2 types of sectional matrix bands. All the cavities were restored using Clearfil Photo Bond and Clearfil AP-X. The tightness of the proximal contact was measured using the Tooth Pressure Meter. Data were statistically analyzed using SPSS 12. ANOVA was used to find differences in proximal contact tightness between the groups. Tukey tests were used to find differences between the homogeneous subgroups. The use of sectional matrices combined with separation rings resulted in tighter proximal contacts compared to when circumferential systems were used (p<0.001). The use of these devices is therefore recommended when posterior resin composite restorations are placed.

A randomized clinical trial on proximal contacts of posterior composites.

OBJECTIVE: The objective of this study was to investigate clinical changes in proximal contact strength inserting Class II composite resin restorations according to one of three randomly assigned protocols. MATERIALS AND METHODS: Seventy-one Class II restorations (MO/DO) were placed by two calibrated operators. Restorations were randomly assigned to one of three groups: one using a circumferential and two a sectional matrix system with separation rings. Proximal contacts were measured by one independent observer with a Tooth Pressure Meter immediately before treatment, and directly after finishing the restoration. RESULTS: Compared to the situation before treatment groups with a sectional matrix system resulted in a statistical significant stronger mean proximal contact strengths (p<0.05), whereas the use of a circumferential matrix system with hand-instrument resulted in a lower proximal contact strength (p<0.05). CONCLUSION: Class II posterior composite resin restorations placed with a combination of sectional matrices and separation rings resulted in a stronger proximal contact than when a circumferential matrix system was used.

[Dental curriculum and team treatment concept]. / De tandheelkundige opleiding en het teamconcept.

The changing oral situation in the Netherlands, the upgrading of the dental hygienist training and the introduction of the bachelor and master degree in the Dutch higher education system asks for a new dental professional: the oral physician. To prepare the oral physician for his role as leader of a dental team several changes and new developments are necessary in the existing dental curriculum.

Clinical evaluation of Dyract in primary molars: 3-year results.

PURPOSE: To evaluate the 3-year clinical performance of Dyract in primary molars. MATERIALS AND METHODS: In 55 children (aged 4-9 years) 91 restorations were placed and 76 were available for evaluation after 2 years. After 3 years, 40 teeth were exfoliated leaving 37 restorations for evaluation. RESULTS: During the entire study, four restorations failed and had to be replaced. One restoration fractured after 6 months and another after 1 year. Two other restorations were completely lost between the second and third year's evaluation. Furthermore, three restorations showed minimal recurrent caries, which did not need additional treatment. Wear of the restorations was considerable. However, this was also true for the point of reference for the wear measurement on the primary molars. The excellent handling characteristics and the low failure rate during the 3-year study suggest that this compomer is a reliable restorative material in primary molars.

Necessity of bevels for box only Class II composite restorations.

STATEMENT OF PROBLEM: The tooth preparation of a bevel is recommended to improve marginal quality of a composite restoration. However, in small Class II restorations, it is unclear if a bevel also contributed to a better marginal fit. PURPOSE: This study investigated the influence of tooth preparation design on microleakage of minimal posterior Class II composite restorations. MATERIAL AND METHODS: Box-shaped Class II tooth preparations for posterior composite restorations in maxillary premolars were restored with a total etch technique. The tooth preparations were beveled or non-beveled and the box prepared at a right angle cervically or additionally excavated. The facial and lingual box margins were also either beveled or unbeveled. The teeth were thermocycled and immersed in a dye solution. After sectioning specimens, dye penetration at the facial and palatal margins was recorded. RESULTS: A bevel-reduced microleakage both at the cervical and ascending walls. Enamel cracks were observed along certain unbeveled margins as recorded in this study. The additional excavation did not contribute to reduction of microleakage. CONCLUSIONS: Tooth preparation of a bevel is recommended for an optimal marginal seal in small box-type Class II composite restorations.

Effect of 6-monthly applications of chlorhexidine varnish on incidence of occlusal caries in permanent molars: a 3-year study.

OBJECTIVES: The aim of this study was to assess the effect of a chlorhexidine varnish on occlusal caries incidence when applied 6-monthly into the fissures of erupting and freshly erupted permanent molars. METHODS: In a double-blind clinical trial, 332 children aged 5/6 and 11/12 years attending a Child Dental Health Centre were randomly assigned to a control and an experimental group. Criteria for inclusion in the study were that all first permanent molars in 5-6-year-olds and all second permanent molars in 11-12-year-olds either had recently erupted, or were in a stage of eruption, or would erupt within half a year. At baseline, counts of dmfs/DMFS and mutans streptococci in saliva were recorded. During a maximum of 3 years, every 6 months the occlusal surfaces of molars in the experimental group received a 40% chlorhexidine varnish application, whereas those in the control group received a placebo varnish application. RESULTS: Data of 316 children were analysed and ANOVA showed no significant occlusal caries reduction in this sample of Dutch 5/6- and 11/12-year-old children. After stratification into low and high caries risk groups, a statistically significant caries-reducing effect on occlusal caries in permanent molars was found in the group of children with > or = 10(6) mutans streptococci per ml saliva (P < 0.05). CONCLUSION: Six-monthly application of chlorhexidine varnish has no caries-reducing effect on occlusal caries in recently erupted permanent molars in a population with low caries prevalence.

[Layer thickness of dental adhesives. Relation between layer thickness and viscosity]. / Laagdikte van hechtlakken. Relatie laagdikte en viscositeit.

OBJECTIVE: To investigate the viscosity of two dental adhesives in relation to the adhesive layer thickness. DESIGN: In vitro study. METHODS: The viscosity of several dental adhesives has been determined with a reogoneometer. Both a high and a low viscous adhesive was used to restore class II preparations. These restorations were sectioned and the thickness of the adhesive layer was measured on several defined locations. A statistical analysis was performed. RESULTS: The high viscous adhesive resulted in a thinner layer along the cervical outline of the restoration. With both materials pooling occurred at the line angles of the preparation. On the flat surfaces of the preparations there was a layer of even thickness. CONCLUSION: The differences in thickness of the adhesive layer as often seen on radiographs cannot be explained solely by the use of adhesives with a different viscosity.

Microleakage of Class II box-type composite restorations.

PURPOSE: To investigate whether in small box-type Class II preparations the use of glass ionomer cement, a dentin primer or a different type of conditioner had an effect on the microleakage compared to a more simple total-etch system using a phosphonated bonding agent. MATERIALS AND METHODS: In extracted premolars, 84 box-type Class II composite resin restorations with margins in enamel were made following a standardized protocol. A transparent matrix system was used and the composite resin was applied in two layers. The teeth were restored using a phosphonated total-etch bonding system as a control (Photo Bond). In the experimental groups a glass ionomer lining-cement (Vitrebond), a total-etch adhesive including a primer (Scotchbond Multi-Purpose) and a total-etch adhesive using a self-etching primer (Liner Bond 2) were used. The teeth were thermocycled, immersed in a dye solution and sectioned. The cervical and occlusal dye penetration was assessed. RESULTS: Preventing microleakage was not more effective in the experimental groups than in the control group (P < 0.05). Scotchbond MP groups using maleic acid showed statistically significant more microleakage than the control group (Photo Bond) at the cervical side. Liner Bond 2 and Scotchbond MP groups using maleic acid showed statistically significant more microleakage than the control group at the occlusal side. The use of a lining cement did not improve the quality of the restoration. From this study it was concluded that in this type of restoration, total-etch systems using a primer are not always an improvement.

[Unhealthy differences. Part II. Dental aspects]. / Ongezonde verschillen. Deel. II. Tandheelkundige aspecten.

In the seventies dental caries was present in almost all Dutch children. Nowadays the child population can be divided into two groups: children with no dental caries and children with a relatively high level of dental caries. The lowest percentage of caries free children is found in low SES (= Socio-economic Status) groups. Within the low SES group children of Turkish of Moroccan origin have a higher caries prevalence compared to the youngsters of Dutch origin. However, differences in the level of caries prevalence between children of Dutch and Turkish or Moroccan origin in recent years have declined. The level of oral health in children from risk groups seems to be due to irregular toothbrushing and consequently irregular use of fluoride toothpaste.

Consistency of resin composites for posterior use.

OBJECTIVES: The aim of this study was to compare a large set of resin composites suitable for application in stress-bearing areas on the basis of their consistency. METHODS: A variety of posterior resin composites were tested using an apparatus that was originally designed for determination of the consistency of elastomeric impression materials (ISO 4823, 1992). The consistency of a standardized volume of resin composite was tested in a dark room at 23 degrees C by loading the samples during 60 s with 1625 g. After loading, the circumference of each sample was determined by a digitizer. Results were analyzed using Tukey-HSD multiple comparisons test and Student's t-tests. RESULTS: The consistency of different brands of composites varied considerably. P50 was the material with the thinnest consistency. Significant differences (p < 0.05) in consistency were found between the same brands of material which were applied directly out of the syringe or out of a preloaded tip. Loading a Centrix tip with one composite out of a syringe resulted in a thinner consistency of the material than when taken directly from the syringe. SIGNIFICANCE: A ranking of posterior resin composites is presented to enable a material selection based on consistency.

Cavity wall adaptation and voids in adhesive Class I resin composite restorations.

OBJECTIVES: Handling characteristics and adaptation modes of resin composites are important factors to achieve proper placement of the restorative materials. The present study was undertaken to assess the influence of the consistency of composite materials and the mode of application on voids and porosities in Class I adhesive restorations. METHODS: One hundred medium-sized Class I preparations with an adhesive design were restored with three composites of various consistencies using three different application modes. The restorations were sectioned, and each section of a restoration was inspected for the presence of voids. The total surface and the percentage of the cavity wall occupied by voids as well as the total number of voids in the sections were recorded. A Krusal-Wallis analysis of variance was carried out on the data. Differences between individual composite materials for each mode of application and between individual application modes for each composite material were analyzed using a Mann-Whitney U-test at p < 0.05. RESULTS: The injection technique with a Hawe Neos Centrix tip was the best mode of application. Both smearing and the condensation of composites appeared to produce unreliable results. Furthermore, there were more problems with voids and wall adaptation for the thicker-consistency composite than for the medium- and thin-consistency material. SIGNIFICANCE: The thick-consistency composite had more problems related to voids and wall adaptation than the medium- and thin-consistency composites.

Changes in dental attitude and behavior among Dutch adults wearing complete dentures.

In 1992 a follow-up on the Dutch National Dental Survey of 1986 (DNDS) was performed. The main objective was to detect and analyze changes in oral self care, dental attendance, and oral health status. This paper will focus on the DNDS adults wearing complete dentures. Changes over a 6-yr period will be presented of: dental attendance, denture satisfaction and wearing of the complete dentures, and denture treatments. A postal questionnaire was used: 232 persons (64%) participated in the study. Analysis of Variance (ANOVA) was used to study the effect of dental and social variables on observed changes since 1986. Risk ratios (RR) were computed to clarify the actual effects of these variables. With respect to dental attendance, a shift towards visits for denture check-ups was found, thought to reflect the respondents' concern for their complete dentures (RR = 1.6). A small shift towards more visits because of denture problems was found. This was attributed to denture treatments that had taken place between 1986 and 1992 (RR = 2.8). With respect to changes in denture satisfaction, no influence of denture treatments could be noted, but a relation was found with a variable indicating the imperfection of the complete dentures as felt by the respondents (RR = 2.8). In 31% of the respondents some denture treatment had been performed since 1986. No objective dental criteria of complete dentures and denture bearing areas had influenced these denture treatment decisions, but only respondents' subjective criteria (RR = 1.9-2.9).

Lactobacilli, mutants streptococci and dental caries: a longitudinal study in 2-year-old children up to the age of 5 years.

A 3-year cohort study was carried out in 252 pre-school children for early identification of caries-active individuals. During this period information was collected about the acquisition of mutants streptococci and lactobacilli from the age of 2 till 5 years old. At baseline mutants streptococci were detected in 43% of the children while the detection frequency of lactobacilli was low (11.5%). On an individual level, numbers of colony-forming units of mutans streptococci and lactobacilli in plaque and saliva varied largely during the study period. The correlations between the numbers of lactobacilli and mutants streptococci in the saliva of the mother and the saliva and plaque of the child were low and never exceeded r = 0.22. Very low correlations (< r = 0.22) were also found between the numbers of mutans streptococci or lactobacilli and the diet in terms of the number of sugar intakes. Nevertheless, in children older than 2.5 years correlations between the clinical caries score and lactobacilli in saliva (range 0.31-0.62) and mutans streptococci in plaque or saliva (range 0.24-0.46) were highly significant (p < 0.01).

Cosmetic dental treatment in an adult Dutch population.

In 1992 a follow-up to the Dutch national dental survey of 1986 (DNDS) was performed. The main objective was to analyse changes in oral self care, dental attendance, and oral health status. A postal questionnaire was used: 936 persons (44 per cent response) participated in the study. This paper will focus on the results concerning cosmetic dental treatment. Stepwise regression analyses were used to study the effect of dental and social variables. Relative risks (RR) were computed to clarify the effect of these variables. Of the group of respondents, 90 persons reported having been treated with veneers on their anterior teeth. The variables indicating cosmetic dental treatment needs established during the DNDS clinical dental examination, showed a statistically significant influence. 'Objective need': RR = 2.6; 'Subjective need': RR = 2.1. Out of 877 respondents with restorations present in 1986, 19 per cent reported having one or more of them replaced by composite or porcelain. Four variables were found to have a statistically significant influence: 'Subjective need': RR = 1.7; 'Number of filled tooth surfaces': RR = 1.6; 'Number of decayed tooth surfaces': RR = 1.4; and 'Frequency of toothbrushing': RR = 1.6. Whereas the dentists' opinions had the most influence on having veneer treatments, the patients' opinions had more influence on having amalgam restorations replaced with composite or porcelain.

Prevalence in the Dutch adult population and a meta-analysis of signs and symptoms of temporomandibular disorder.

A nationwide survey of oral conditions, treatment needs, and attitudes toward dental health care in Dutch adults was carried out in 1986. One of the aims of the study was to assess the prevalence of signs and symptoms of temporomandibular disorder (TMD). A sample of 6577 persons (from 15 to 74 yr of age), stratified for gender, age, region, and socio-economic status, was contacted. Of this sample, 4496 persons participated in the behavioral part of the study, of whom 3526 were examined clinically. The TMD prevalence was based on (1) perceived signs and symptoms of TMD and (2) clinical examination of joint sounds, deviation, and pain on mandibular movements. A total of 21.5% of the Dutch adult population perceived some dysfunction, and 44.4% showed clinically assessed signs and symptoms of TMD. In nearly all age groups, the signs and symptoms of TMD appeared more in women than in men. Agreement between the results of the clinical examination and the anamnestic dysfunction index was significant (p < 0.0001); however, the Pearson's correlation coefficient was low (r = 0.29). The odds-value (risk-ratio) that subjects who perceived signs and symptoms of TMD would present with clinically assessed signs and symptoms of TMD was 2.3. The results of the survey were compared with results of a meta-analysis performed on 51 TMD prevalence studies. The analysis revealed (1) a perceived dysfunction rate of 30% and (2) a clinically assessed dysfunction of 44%, both based on compound samples of, respectively, over 15,000 (23 studies) and over 16,000 (22 studies) randomly selected subjects.