Role of arginine and fluoride in the prevention of eroded enamel: an in vitro model.

BACKGROUND: The aim of this study was to investigate the effect of arginine and fluoride on the reduction of erosive wear. METHODS: Bovine enamel blocks were randomly allocated into four groups (n = 20) and exposed to: ESPR group (8% arginine, 1450 ppm sodium monofluorophosphate, calcium carbonate and titanium dioxide); ESen group (1450 ppm sodium monofluorophosphate, 5% potassium citrate); positive control PC group (1500 ppm sodium monofluorophosphate) and negative control NC group (water). The samples were submitted to six alternating cycles of demineralization-remineralization (cola, 10 minutes; artificial saliva, 1 hour, respectively). Before and between cyclic demineralization and remineralization, blocks were treated with slurries of the respective toothpastes or water (1 minute). Erosive tissue loss was analysed by microhardness and profilometry. Data were analysed by ANOVA and Tukey tests for individual comparisons among the groups (p < 0.05). RESULTS: In microhardness, the ESPR (217.46 ± 55.45) group was significantly better than the other treatment groups (PC = 302.76 ± 96.10; ESen = 315.56 ± 74.56; p < 0.001). The ESPR group showed a similar loss to NC group (NC = 210.8 ± 49.98; p = 0.991). The mean erosion depth (+/- SE, µm) was detected between NC (14.37 ± 1.72) and dentifrices tested (ESPR (4.11 ± 1.34), ESen group (7.64 ± 1.61) and PC (8.20 ± 2.19) (p = 0.000). CONCLUSIONS: From the results of the present study, the effectiveness of Sensitive Pro Relief in the prevention of erosive surface loss seems to be attributed to the possible effect of the arginine associated with fluoride.

The relationship between tooth wear in the primary and permanent dentitions.

OBJECTIVE: To evaluate the relationship between tooth wear in primary and permanent dentition in 7 to 10-year-old school children, in 2007. METHODS: An epidemiological cross-sectional survey was conducted by trained, calibrated examiners, using the dental wear index (DWI). The cluster sample consisted of 764 children (382 boys, 382 girls) attending 4 public schools selected in different regions of the city. The DWI was proposed to evaluate primary and permanent teeth, coded as letters and numbers, respectively. Data were collected via clinical examinations performed outdoors under natural light, following the WHO recommendations and using a dental mirror and probe. Proportions and confidence intervals were used to describe the prevalence of dental wear. The Mann-Whitney and the Odds Ratio (OR) tests were used to compare the tooth wear prevalence between primary and permanent teeth according to surface (p < 0.05). RESULTS: The 7 to 10-year-old school children presented 16% tooth wear. The tooth wear was mostly seen on the occlusal/incisal surfaces (47%), involving enamel or enamel-dentine. Tooth wear in primary teeth was found in canines and molars (93%) and in permanent teeth in molars (34%). There was significant difference between primary and permanent teeth (p < 0.001) and dental wear in primary teeth was greater in boys than in girls (p = 0.02) but not in permanent teeth. CONCLUSION: The results suggest that 7 to 10-year-old children with tooth wear in primary teeth had more chances of developing tooth wear in permanent dentition. However, the findings of this study are not conclusive as the associations described are not causal.

Prevalence of dental wear among 12-year-old Brazilian adolescents using a modification of the tooth wear index.

OBJECTIVE: This study investigated the prevalence of dental wear in 12-year-old adolescents using a modification of the tooth wear index (TWI). The modifications were proposed in order to fit with the World Health Organization standard, thus allowing application of the index in broad epidemiological surveys. STUDY DESIGN: An epidemiological cross-sectional survey was performed by trained, calibrated examiners, using a modified version of the TWI. METHODS: Urban elementary schools were chosen because they provide a fair representation of the city's population in terms of socio-economic status. The sample included 295 adolescents, selected randomly and systematically. Dental wear was assessed by calibrated examiners (kappa>0.85), using a modified version of the TWI. This modified version includes a code for teeth restored due to wear, and another code for teeth that cannot be assessed. In addition, it does not differentiate the depth of dentine involvement. Proportions and confidence intervals were used to describe the prevalence of dental wear. Mann-Whitney test was used to detect differences in the degree of dental wear between males and females. The level of statistical significance was set at 5%. RESULTS: In total, 24,780 dental surfaces were evaluated. Among these surfaces, 73.10% did not present dental wear, 24.10% had incipient lesions, 2.46% had moderate lesions and 0.34% had been restored. No severe lesions were detected. Tooth wear was mainly seen on the occlusal/incisal surfaces (26.55%), involving enamel or enamel-dentine, but not the secondary dentine or pulp. The prevalence of dental wear was 26.90%. Considering the different teeth, wear was present in 53.22% of incisors, 50.51% of canines, 10.17% of premolars and 10.85% of molars. The prevalence of the different degrees of dental wear was similar in males and females (P>0.05). CONCLUSION: The modified TWI seems to be an effective tool for use in broad epidemiological surveys, due to easier calibration and high reproducibility rates.

Distribution and prevalence of dental caries in Bauru, Brazil, 1976-2006.

AIMS: To compare caries prevalence and severity, as well as the disease distribution in the permanent dentition of 12-year-old schoolchildren in Bauru, Brazil, from 1976 to 2006. METHODS: Probabilistic samples were obtained in six surveys, from 1976 to 2006, which were conducted by calibrated examiners, following the same protocol. For data analysis, the DMFT (decayed, missing and filled teeth), Significant Caries Index (SiC Index), percentage of caries-free children, Gini Coefficient and Care Index were determined. RESULTS: The means (SD) for DMFT were 9.89 (3.96), 6.98 (3.80), 4.30 (3.11), 4.29(3.44), 1.53(2.07), and 0.90(1.53) in 1976, 1984, 1990, 1995, 2001 and 2006, respectively. Except for years 1990 and 1995 and also for 2001 and 2006, there were statistically significant differences in mean DMFT among the surveys (p < 0.05). The number of caries-free children (DMFT=0), which has significantly increased over the years (p < 0.001), ranged from 0.4% in 1976 to 63.8% in 2006. The SiC Indexes were 14.34, 11.42, 7.74, 8.06, 3.89, and 2.63; the Care Index were 31.9%, 57.4%, 68.7%, 50.5%, 66.4%, and 56.3%; and the Gini Coefficients were 0.23, 0.30, 0.39, 0.43, 0.66, and 0.76 in the surveys. CONCLUSION: Dental caries experience and prevalence in 12-year-old schoolchildren have declined significantly during the last 30 years in Bauru.