The Relation between 6-n-Propylthiouracil Sensitivity and Caries Activity in Schoolchildren

Caries activity tests are being used to assess caries risk in children. In recent years the purpose of most studies has been to develop practical, quick, reliable and economic tests. Clinical studies showed that the difference in sensitivity to the bitter taste of 6-n-propylthiouracil (PROP) is a heritable trait and may influence children's nutritional habits and caries development. The aim of this study was to investigate the relation between PROP sensitivity and caries activity in schoolchildren, in comparison with different caries activity tests. One hundred and twenty children aged between 7 and 12 years (mean age 9.97 +/- 1.59) were investigated to determine socioeconomic status and oral hygiene habits, fluoride consumption, DMFT, DMFS, df, dfs, plaque indexes, and nutritional habits. Children were divided into three groups according to their caries risk status based on the Cariogram. The solution test and the PROP-impregnated filter paper test were used together to determine PROP sensitivity. After all associated factors had been controlled, stepwise regression analyses revealed that DMFT and dfs scores were important determinants of PROP. According to dfs, the sensitivity of the Cariogram and of PROP tests was 0.85 and 0.70, respectively, and specificity was 0.32 and 0.33, respectively. There was an inverse significant relationship between PROP sensitivity and DMFT, DMFS, and dfs results (p < 0.01). In conclusion, PROP nontasters were significantly more likely to have high caries risk than PROP tasters (p < 0.01). Copyright (C) 2011 S. Karger AG, Base

The effect of enamel bleaching on the shear bond strengths of metal and ceramic brackets

The aim of this study was to evaluate the effects of bleaching and delayed bonding on the shear bond strengths of metal and ceramic brackets bonded with light and chemically cure composite resin to human enamel. One hundred and twenty extracted human premolar teeth were randomly divided into three groups of 40 each. The first two groups were bleached with 20 per cent carbamide peroxide (CP) at-home bleaching agent. No bleaching procedures were applied to the third group and served as control. The first two and control groups were divided into equal subgroups according to different adhesive-bracket combinations. Specimens in group 1 (n = 40) were bonded 24 hours after bleaching process was completed while the specimens in group 2 (n = 40) were bonded 14 days after. The specimens in all groups were debonded with a Universal testing machine while the modified adhesive remnant index was used to evaluate fracture properties. No statistically significant differences were found between the shear bond strengths of metal and ceramic brackets bonded to bleached enamel after 24 hours, 14 days, and unbleached enamel with light or chemical cure adhesives (P > 0.05). The mode of failure was mostly at the bracket/adhesive interface and cohesive failures within the resin were also observed. Our findings indicated that at-home bleaching agents that contain 20 per cent CP did not significantly affect the shear bond strength of metal and ceramic orthodontic brackets to enamel when bonding is performed 24 hours or 14 days after bleaching

Clinical performance of sealants with and without a bonding agent

Objectives: The objective of this study was to assess the effect of a one-bottle bonding agent on sealant success after 3, 6, 12, and 24 months. Method and materials: The sample group consisted of 30 schoolchildren (8 to 10 years of age) who had all their permanent first molars sound and unsealed. Occlusal sealants were placed on first molars according to a split-mouth design. Sealant scoring occurred at 3, 6, 12, and 24 months and was performed by two clinicians blinded to the treatment group. Fisher's exact test was used to analyze the data. Results: The clinically acceptable marginal integrity rates for sealants with a bonding agent after 3, 6, 12, and 24 months were 93%, 93%, 83%, and 79%, respectively. For sealants without a bonding agent, the clinically acceptable marginal integrity rates after 3, 6, 12, and 24 months were 90%, 88%, 81%, and 77%. The rates for no color change in sealants with a bonding agent after 3, 6, 12, and 24 months were 96%, 93%, 81%, and 75%, respectively. For sealants without a bonding agent, the no color change rates after 3, 6, 12, and 24 months were 93%, 93%, 79%, and 72%. After 24 months, 73% of the sample group were available for recall. The retention rates for sealants with and without a bonding agent after 24 months were 79% and 75%, respectively. The results of the statistical analysis showed that there were no differences among the sealants with and without bonding agents evaluated in relation to marginal integrity, marginal discoloration, and anatomic form. Conclusion: The success of a sealant is related to whether the sealant is applied under optimal conditions. The results of this study show that at the 2-year mark, the placement of a bonding agent under sealants did not significantly affect the clinical success of sealants

Bacteria and salivary profile of adolescents with and without cleft lip and/or palate undergoing orthodontic treatment

Background: Patients with cleft lip and/or palate (CL&/P) experience a higher caries prevalence. This study aimed to determine if patients with CL&/P, undergoing and not undergoing orthodontic treatment, have a different salivary biochemical profile and different salivary levels of Mutans Streptococci (MS) and Lactobacilli (LB) compared to patients undergoing and not undergoing orthodontic treatment without CL&/P. Methods: One hundred and ten subjects aged between 12 and 17 years were recruited into one of four different groups comprising two control groups and two treatment groups. The control groups comprised of subjects with and without CL&/P who were not undergoing orthodontic treatment. The treatment groups comprised of subjects with and without CL&/P undergoing orthodontic treatment. Regular reinforcement of oral hygiene instructions, dietary counselling and debridement, when necessary, were offered to subjects in the treatment groups following their orthodontic adjustment appointments. The salivary secretion time, pH of resting and stimulated saliva, salivary flow rate, buffering capacity, quantity of salivary MS and LB were measured. Results: Subjects with CL&/P undergoing orthodontic treatment at the Children's Oral Health Service tended to present with microbiological and salivary profiles that were less favourable for caries development. There was a significant difference in the percentage of subjects with >105 colony forming units (CFU)/mL of MS between the cleft treatment and non-cleft treatment groups. Subjects in the non-cleft treatment group had the highest percentage of subjects (86.7 per cent) with >105 CFU/mL of MS whereas subjects in the cleft treatment group had the lowest percentage of subjects (60 per cent) with >105 CFU/mL of MS. For LB, there were significantly higher percentages of subjects with >105 CFU/mL of LB in the non-cleft treatment (76.7 per cent) and cleft treatment (73.3 per cent) groups compared to the non-cleft control (46.7 per cent) and cleft control (40.0 per cent) groups. Conclusions: Regular oral hygiene reinforcement and dental health education appears to have a positive effect in reducing the percentage of subjects with >105 CFU/mL of MS.LL Cheng, SL Moor, O Kravchuk, IA Meyers, CTC H

Predisposing factors to dental caries in children with cleft lip and palate: A review and strategies for early prevention

Objective: To review predisposing factors contributing to dental caries in patients with cleft lip, cleft palate, or both (CUP). Design: Patients with CUP have a higher susceptibility to caries compared with the population group without clefts. A review of the literature was undertaken to determine factors that could account for the compromised oral hygiene and the high caries prevalence in patients with CUP. Results: After a literature review, modern strategies for the prevention of early childhood caries were developed and should be considered for integration into the overall management protocol of patients with CUP. Conclusions: Preventive dental care is ever more so important in patients with CUP compared with patients without clefts