Plaque fluoride concentrations in a community without water fluoridation: effects of calcium and use of a fluoride or placebo dentifrice.

The results of a recent study by Whitford et al. [Caries Res 2002;36:256-265] with subjects whose drinking water was fluoridated led to two major conclusions: (1) Compared to the use of a placebo dentifrice, plaque fluoride concentrations ([F]) throughout much of the day are not significantly increased by the use of an F dentifrice but (2) they are positively related to plaque [Ca] (p = 0.0001). The present double-blind, double-crossover study with 16 subjects used the same protocol and was done to: (1) determine the effects of the use of an F dentifrice on salivary and plaque [F] in a community without water fluoridation and (2) further examine the relationship between plaque [Ca] and [F]. Following the use of an F dentifrice or placebo for one week, whole saliva and plaque were collected 1.0 and 12 h after the last use of the products. The study was repeated to include rinsing with a 20 mmol/l CaCl(2) solution immediately before the use of the dentifrices. The CaCl(2) rinse had only minor effects on salivary [Ca] and [F] and none on the plaque concentrations. Unlike the results found in the fluoridated community, all salivary and plaque [F] associated with the use of the F dentifrice were significantly higher than those associated with the use of the placebo. The results suggest that the cariostatic effectiveness of an F dentifrice should be greater in areas without water fluoridation. As noted previously, plaque [F] were positively related to plaque [Ca] (p = 0.0001).

In vitro quantitative evaluation of marginal microleakage in Class II restorations confected with a glass ionomer cement and two composite resins.

This study evaluated, in vitro, marginal microleakage in class II restorations confected with the glass ionomer cement Vitremer and with the composite resins Ariston pHc and P-60. The aims of the study were to assess the effect of thermocycling on those materials and to evaluate two methods utilized in the analysis of dye penetration. Sixty premolars divided in three groups were utilized; the teeth had proximal cavities whose cervical walls were located 1 mm below the cementoenamel junction. Half of the test specimens from each group underwent thermocycling; the other half remained in deionized water, at 37 degrees C. The specimens were immersed, for 24 hours, in a basic 0.5% fuchsin solution at 37 degrees C. For the analysis of microleakage, the specimens were sectioned in a mesio-distal direction, and the observation was carried out with the software Imagetools. The results were evaluated through the 2-way ANOVA and through the Tukey's test. All groups presented marginal microleakage. The smallest values were obtained with Vitremer, followed by those obtained with the composite resins P-60 and Ariston pHc. There was no statistically significant difference caused by thermocycling, and the method of maximum infiltration was the best for detecting the extension of microleakage.

Occurrence of primary incisor traumatism in Brazilian children: a house-by-house survey.

This paper presents the results of a house-by-house survey to learn the occurrence of dental injury to the primary teeth in Brazilian children from ten to seventy-two months of age. The study sample comprised 576 children, 295 boys and 281 girls living on sixty-six streets selected in an urban area (Bauru) in the state of Sao Paul, Brazil. There were 174 children (30.2 percent) with positive reports of injuries to the primary teeth. The results show the need of an educational program in order to prevent the occurrence of dental trauma.

[Effect of cetylpyridinium chloride on formation and metabolism of human dental plaque]. / Efeito do cloreto de cetilpiridínio sobre a formação e o metabilismo da placa dentária humana.

In this work, the Cepacol (cetylpyridinium chlorid) diluted 1:2, when used for mouthwashes three time a day decreased the "in situ" formation of human dental plaque, however it didn't decreased neither the plaque fermentation, nor the IEP synthesis by the plaque. When the Cepacol was used for treating the "in vitro" dental plaque in both 1:10 and 1:20 dilutions, decreased the fermentation and the IEP synthesis of the "in vitro" plaque.

Comparison of dental prophylaxis and toothbrushing prior to topical APF applications.

This study was conducted to evaluate the effect of dental prophylaxis prior to the topical application of acidulated phosphate fluoride solution applied twice a year in schoolchildren. Experimental groups were: Group I--control group, had no treatment. Group II--twice yearly topical application of acidulated phosphate fluoride solution with prior professional prophylaxis with rubber cup and non fluoride paste. Group III--twice yearly topical application of acidulated phosphate fluoride solution with prior toothbrushing with a non-fluoridated prophy paste. After 18 months analysis of 160 children in each study group led to the following conclusions: 1. Acidulated phosphate fluoride topical applications are effective in the prevention of dental caries. 2. The omission of a professional prophylaxis prior to topical fluoride application does not affect significantly the caries preventive effect.