The impact of bias of underlying literature in guidelines on its recommendations: assessment of the German fluoride guideline.

PURPOSE: The significance of the underlying literature in clinical guidelines can be weakened by the risk of bias, which could negatively affect the recommendations. Especially in controversial matters, such as fluoride use for caries prevention in children, biased results may be not reliable and lead to incorrect conclusions. This study was performed to detect bias in underlying literature of the German guideline for caries prevention using fluoride in children, where no consensus was reached between paediatricians and paediatric dentists. METHODS: Three tools used for risk of bias assessments of different study designs were RoB 2 for RCTs, ROBINS-I for non-randomized studies, and ROBIS for systematic reviews. For each study cited in the guideline two independent risk of bias assessments were performed. Disagreements were resolved by consensus. RESULTS: Out of 58 papers, 48.3% (n = 28) showed high risk of bias, with the majority in sections regarding fluoride tablets, fluoridated toothpaste, and paediatricians' recommendations. 9 out of 20 recommendations and statements were based on studies with high risk of bias, all of which were in these three controversial sections. 13 out of 29 RCTs showed high risk of bias (44.8%), as all 13 non-randomized trials did, while only 2 of 16 (12.5%) systematic reviews had high risk of bias. CONCLUSION: Considering risk of bias of cited studies in clinical guidelines may result in substantial changes in its recommendations and aid in reaching consensus. Efforts should be made to assess risk of bias of underlying literature in future clinical guidelines.

Severity of MIH findings at tooth surface level among German school children.

AIM: This study was to investigate the distribution and clinical characteristics of teeth diagnosed with MIH at surface and defect type level in a cohort of German children. METHODS: The study cohort included 242 children diagnosed with MIH which had been recorded during the compulsory dental school examinations of 20 German primary schools. The subjects had been enrolled by cluster sampling. All children attended the second to fourth grade (age 7-10 years, mean 8.1 ± 0.8). The children were examined by five calibrated examiners (kappa = 0.9) after tooth brushing. The recording comprised teeth, surfaces, type and severity of MIH defects and was conducted using a portable light, mirrors and cotton rolls. MIH was registered according to the EAPD criteria. Defects <1 mm were not recorded. Statistical analysis included descriptive statistics and Spearman's correlation. RESULTS: Most affected teeth were first permanent molars (71.4 %) followed by the maxillary central incisors (15.6 %). The most common defects were demarcated opacities (82.2 %), while the remaining 17.8 % of the affected teeth exhibited severe enamel defects. The most frequently affected surface in molars was the occlusal surface (72.4 %); in incisors, it was the buccal surface (73.5 %). There were no atypical restorations in the affected incisors. Different types of MIH defects at various surfaces of the same tooth were common. The number of affected tooth surfaces was positively correlated with the severity of MIH at child (p < 0.001). CONCLUSIONS: The study demonstrates severe enamel defects involving in almost one-fifth of all MIH teeth. The knowledge of the intra-oral distribution and severity of MIH findings at the enamel surface level is important for assessing the treatment needs.

Oral health in German children, adolescents, adults and senior citizens in 2005.

OBJECTIVE: The aim of this field study (the "Fourth German Oral Health Study") was to obtain representative data on caries (DMFT index), periodontitis (CPI) and prosthetic status in the German population and to evaluate changes in the oral health of the German people as compared with the findings of the Third German Oral Health Study conducted eight years previously. BASIC RESEARCH DESIGN: The study took the form of a population-representative cross-sectional survey with random samples, and was complemented by a questionnaire to reveal sociological as well as behavioural data. PARTICIPANTS: The age cohorts in the present study were 12-year-olds (children), 15-year-olds (adolescents), 35- to 44-year-olds (adults) and 65- to 74-year-olds (senior citizens). RESULTS: All age groups showed considerable improvements in oral health with respect to caries. Of the children, 70.1% were free of dentine caries and the mean DMFT value was 0.7. In adults and senior citizens both the DMFT value and the number of missing teeth and edentulousness declined. With regard to periodontal conditions, increasing prevalence of moderate and severe findings was recorded in adults and senior citizens, owing probably to the larger number of natural teeth remaining in the oral cavity. CONCLUSION: The study documents a distinct improvement in oral health in the German population. Interrelated with the higher numbers of remaining natural teeth a higher prevalence of moderate and severe periodontal conditions in German adults and senior citizens was observed.

Reproducibility of a new caries risk test under different oral conditions.

The aim of the present study was to evaluate the reproducibility of the caries risk test Clinpro Cario L-Pop (3 M Espe, D-Seefeld), which measures the lactic acid produced by different bacteria of the oral flora, under stable oral conditions. In a group of healthy volunteers (n=31), the test was carried out ten times during 2 weeks. During the test period, the subjects were requested not to change their oral hygiene habits to ensure stable oral conditions. To register possible alterations of oral conditions by medication, a questionnaire was used. In subjects who did not alter their oral conditions (n=20), the reproducibility was 82.0%, with especially low score variations in subjects with low lactate signal scores. Some subjects exhibited, mainly due to colds and their medication, alterations in their oral conditions. The reproducibility in this group was 60.0%. Both reproducibility values differ significantly. In conclusion, the new diagnostic device shows high reproducibility under stable oral conditions. The lower reproducibility under altered oral conditions gives evidence that the test might reflect changes in the oral microflora following preventive interventions and thus could be used to monitor the effect of such interventions.

[Wedge-shaped defects of the neck of the tooth in regular brushing with an amine fluoride gel]. / Keilförmige Zahnhalsdefekte bei regelmässiger Bürstapplikation eines aminfluoridhaltigen Gelees.

Gingival recession and wedge-shaped defects are caused mainly by incorrect tooth brushing procedures. The aim of this epidemiologic study was to determine if in addition there is a relationship to the regular use of an amine fluoride gel (pH 5.2) applied by a toothbrush. In a regression analysis, the effect of age, sex, education, toothbrushing frequency, gingival bleeding (PBI) and use of the gel on the occurrence of wedge-shaped defects was investigated. Similarly, the influence of these variables on the occurrence of gingival retraction without any hard tissue defect was investigated. Both types of lesions showed a statistically significant relationship to age and PBI. Moreover, use of the amine fluoride gel was significantly and negatively correlated with the occurrence of wedge-shaped defects.

[Preserving primary dentition until permanent teeth erupt]. / Die Erhaltung des Milchgebisses bis zum Zahnwechsel.

International and regional trends in caries decline are described and a review of the efficacy of different caries preventive regimens in kindergarten children is given. It is concluded that in a situation of established oral hygiene in many kindergartens now the quality of this regimen has to be improved. Controversies about restorative materials used for deciduous teeth support the measures of caries prevention.

[Inter- and intrapersonal coincidence of caries epidemiologic data]. / Zur inter- und intrapersonellen Ubereinstimmung von epidemiologischen Kariesbefunden.

For testing the reliability of caries epidemiologic data a group of 273 children, aged 7 to 15 years, was examined by two dentists. A second group of children was investigated twice by one examiner at an interval of two weeks. Neither an inter-examiner nor an intra-examiner comparison of these data did indicate any statistically significant differences in caries incidence.

[The adaptive responses of human oral microorganisms to sorbitol]. / Zum Adaptationsverhalten von Mikroorganismen der menschlichen Mundhöhle gegenüber Sorbit.

It was the goal of this study to evaluate the extent to which sorbitol is metabolized by the oral microflora of persons adapted to this sugar substitute (diabetics). Resting saliva of 25 test persons with juvenile diabetes mellitus was incubated with sorbitol or sucrose in the Warburg-system both under aerobic and under anaerobic conditions. Saliva of 25 healthy persons served as control. Sorbitol was metabolized faster and to a higher total amount in the diabetic group. These results indicate that if sorbitol is offered continuously, the oral microflora will adapt and will metabolize sorbitol to a considerably higher extent.

[Defect rate of disposable gloves after longer treatment duration]. / Defekthäufigkeit an Einmalhandschuhen nach längerer Behandlungsdauer.

Following 472 dental treatments the disposable gloves worn by dental assistant staff were examined for perforations. 73% of polyvinyl chloride glove pairs had at least one defect. Therefore these gloves hardly meet the requirements of the regulations for the prevention of accidents in relation to the tightness of gloves to liquids. 24% of the latex glove pairs lacked tightness. These values correlate with those found for dentist's gloves. For both types of materials the incidence of defects increases significantly with treatment duration. Since visual checks only detected one third of the perforations, longer term use of disposable gloves for several treatments can not be recommended.

[Influence of caries preventive measures on prevalence and incidence of caries in Hamburg preschool children]. / Der Einfluss kariespräventiver Verhaltensweisen auf Kariesbefunde von Kindern im Vorschulalter.

A decline in caries prevalence and incidence was observed in preschool children in Hamburg kindergardens and day care centres. On the occasion of dental exams staff and children were interviewed about measures of caries prevention. It was possible to establish complete records about oral hygiene, intake of sweets in the institutions, and ingestion of fluorides. Statistical analyses demonstrated that, apart from age and social class, the social environment of the children was of significant influence. The prevalence of caries also was significantly a function of the intake of sweets in the institution. The incidence of caries and fluoride ingestion at home correlated with high significance. The reduction of caries in Hamburg preschool children is predominantly due to the reduced intake of sweets in kindergardens and day care centres.

[Uptake and release of fluoride in enamel surface after fluoridation]. / Aufnahme und Abgabe von Fluorid an der Schmelzoberfläche nach Fluoridierung.

After one single application of a sodium monofluorophosphate or sodium fluoride solution (1%) in an in vitro study, the incorporation of fluoride into enamel platelets was determined. Compared with sodium fluoride the increase in the fluoride concentration following the application of sodium monofluorophosphate was significantly lower, whereas the loss of fluoride after four weeks of rinsing with an artificial saliva solution was markedly reduced. The duration of fluoride incorporation may be one of the factors governing the clinical equivalence of both substances. To determine the amount of enamel in which the fluoride content was measured, the elements calcium and phosphor were determined with the aid of nuclear emission spectrometry and compared with photometric phosphate measurements. All three methods produced identical results.