Clinical Evaluation of Aluminum Oxide Abrasion for NCCL Restorations

Objectives: This in vivo randomized, double-blind clinical trial aimed to evaluate the longevity of restorations in NCCLs treated with aluminum oxide abrasion and a universal adhesive system.
Methods: Fifty-four participants were screened and selected at the Special Lasers Laboratory in Dentistry of the University of São Paulo (LELO-FOUSP), following the local ethics committee (5.658.449). The experimental group sequence for each tooth (premolar or molar with NCCLs of at least 1 mm in depth and extension) was determined by a sealed envelope following a randomization sequence. The experimental groups were: ALSet (50 μm aluminum oxide sandblasting + selective enamel etching with Single Bond Universal Adhesive (SBU) (3M); ALTe (50 μm aluminum oxide sandblasting + total etching - enamel and dentin - with SBU); Set (selective enamel etching with SBU); and Te (total etching with SBU). After applying the adhesive system, teeth were restored with Filtek Z350 XT composite resin (3M). Each patient received all four treatments resulting in 216 restorations. Two calibrated researchers assessed the restorations using selected FDI World Dental Federation criteria (surface and marginal staining, retention, marginal adaptation, sensibility, and recurrence of initial pathology) at 1 week (baseline), 6, and 12 months. Data for all groups were analyzed using Friedman and Kruskal-Wallis tests with a 5% significance level.
Results: No significant differences were observed between treatments. After 6 and 12 months, the restorations recorded more surface and marginal staining than the baseline.
Conclusions: Since no differences were found between the experimental groups after 1 year, all treatments can be recommended for restoration of NCCLs.