Effect of Oxalic Acid-Based Desensitizing Agent on Cervical Restorations on Hypersensitive Teeth: A Triple-Blind Randomized Controlled Clinical Trial.

AIMS: To assess the effects of application of an oxalic acid-based desensitizing agent before restoration of noncarious cervical lesions (NCCLs) with either a silorane-based or a methacrylate-based composite resin on decreasing the absolute risk and intensity of dentin hypersensitivity over the course of a 1-year follow-up. METHODS: NCCLs in 31 patients (age range 24-66 years) were selected and randomly divided into four groups (n = 31 in all groups). In the Z250 and P90 groups, the restorations were performed with a methacrylate-based composite resin (Filtek Z250) and a silorane-based composite resin (Silorane P90), respectively. In the Z250 + OA and P90 + OA groups, the same composite resins were used, but an oxalic acid-based desensitizing agent (Desenssiv, SSWhite) was first applied. All NCCLs were evaluated before restoration (BR) and at 30, 60, 90, 180, and 360 days after treatment. Teeth sensitivity to evaporative and tactile stimuli was measured by a visual analog scale (VAS). The results were analyzed with statistical tools including Wilcoxon and Friedman tests for within-group comparisons and ANOVA and Bonferroni post hoc tests for between-group comparisons (P < .05). RESULTS: Reduction in dentin hypersensitivity was observed for all treatment groups; however, these reductions were more pronounced when oxalic acid was applied before restoring the NCCL (P < .001). Complete elimination of pain was not achieved by any treatment modalities for the first 6 months; afterwards, in the groups that had received application of the oxalate-based desensitizing agent, the absolute risk of dentin hypersensitivity was significantly reduced (P < .01). CONCLUSION: The restoration of sensitive NCCLs with composite resins reduces dentin hypersensitivity. This reduction is more pronounced if an oxalic acid-based desensitizing agent is applied prior to the restoration. In addition, its application reduces the absolute risk of dentin hypersensitivity after 6 months of treatment.

Does refurbishing composites lead to short-term effects or long-lasting improvement?

PURPOSE: To evaluate the clinical performance of refurbished resin composite restorations compared to untreated (negative control) restorations over a period of 10 years. METHODS: 26 subjects (having a total of 52 composite restorations) were recruited. All restorations in the refurbished group showed clinical features rated bravo according to modified USPHS criteria. Untreated restorations were those that had been deemed acceptable (alpha or bravo rated); these were used as controls. Two examiners performed assessments at baseline and during the 5th and 10th years after the intervention. Wilcoxon tests were performed for within-group comparisons, Friedman tests were used for multiple within-group comparisons, and Mann Whitney tests were used for between-groups comparisons. Kaplan-Meier survival curves were calculated, and the Mantel-Cox test was used to compare curves. P < 0.05 was considered statistically significant. RESULTS: In both groups, 10-year scores were significantly different from baseline scores in all clinical parameters except secondary caries. There were no statistically significant differences in the survival analysis of groups (log-rank test, P = 0.376). Refurbishing treatment improved the anatomy, roughness, luster, and marginal adaptation of restorations with a short-term effect, with most properties rated acceptable after 10 years of clinical service. The clinical characteristics were similar for all groups at the 10th year.