Objectives:Using an established pH-cycling caries model, the authors evaluated the effectiveness of toothpastes containing Surface Pre-reacted Glass-ionomer filler (S-PRG) in preventing tooth surface demineralization.Materials and Methods:210 tooth blocks were randomly assigned to seven experimental groups (30 blocks/group): no treatment (A), and toothpaste containing either NaF (B), 0 wt% S-PRG (C), 1 wt% S-PRG (D), 5 wt% S-PRG (E), 20 wt% S-PRG (F) or 30 wt% S-PRG (G). Groups were subjected to 14-day demineralization for development of early caries lesions using a pH-cycling caries model. Demineralization was assessed using Quantitative Light-induced Fluorescence (QLF) and Transverse Microradiography (TMR). All pairwise contrasts (between treatments) were tested using Analysis of Variance (ANOVA), and then Tukey’s HSD for multiple comparisons. All p-values are considered significant if <0.05.Results:With QLF, there was a significant (ANOVA; p<0.001) difference in mean percent fluorescence loss (∆F) observed among the groups. Relative to control, all S-PRG-containing toothpastes significantly (Tukey’s; p<0.0001) inhibited demineralization at varying percentages (48.6%, 61.3%, 67.4% and 69.8% reduction with S-PRG 1%, 5%, 20% and 30% respectively). Demineralization reduction was not significant with either NaF (15.6% reduction) or 0% S-PRG (-2.5% reduction i.e. 2.5% more demineralization than the Control) when compared to control group. Mineral loss assessed using TMR followed a similar trend as fluorescence loss.Conclusion:Toothpaste containing S-PRG filler can serve as an effective caries control tool. S-PRG filler-containing dentifrice to be more effective in preventing tooth demineralization than 1100 ppm fluoride provided as sodium fluoride.

Inter-observer variability was determined using the Dahlberg formula. The percentage of sites with no FABr at each level was compared between sex, implant type and location using Fisher's Exact test (p ≤ 0.05).vi Results: 55% of all implants have no FABr at the implant/abutment interface. FABr thickness is greater in the apical as compared to the cervical half of all implants (p=0.04).Edentulous spaces restored with tapered implants showed greater radiographic FABr in the apical region than with parallel implants (p=0.04).