RESTORATION OF CERVICAL LESIONS:7-YEAR RESULTS OF A RCT

A randomized controlled trial represents the best solution for checking the clinical performances. Objectives: The aim of the study was to test two all-in-one bonding systems vs a 3-step E&R in cervical abrasion/erosion lesions with the null-hypothesis of no difference between the three bonding systems. Methods: A randomized controlled trial was scheduled on 50 patients, 22 males, 28 females, aged between 30-52, with 3 cervical lesions, respecting the inclusion-exclusion and randomisation criteria for selection of technique and teeth. The materials selected were i-Bond(H) (Heraeus-Kulzer), AQ bond (S)(Morita)and SBMP (M)(3M-ESPE)as control. The procedure was done by 3 operators with 8,4,4-year of experience, all the cavities were restored with Z250 (3M-ESPE), using a layering technique and soft start light-curing with an halogen lamp (Visilux 3000, 3M), with 400 mW/cm2,with a final energy density > 8 J/cm2. The diameter, the depth, the type of dentin and the margin location of the lesions were recorded. ANOVA statistical analysis (P=0.05) was performed. The restorations were evaluated by an examiner with an intra-agreement > .80 with a loop (4.5x) according with USPHS modified criteria at baseline, 6,12,24,36,60,72,84 months. Results: After 84 months 42 patients were assessed: the group S showed 14 failures with 10 restorations lost and 4 rated Charlie for margin infiltration, the group H had 7 failures, with 2 restorations lost and 5 rated Charlie for marginal infiltration, the group M had 6 failures with 1 restoration lost and 5 rated Charlie for marginal infiltration. There is a significant difference between the group S and groups H and M (P=.03), no difference between H and M. Conclusions: Within the limits of this clinical trial, the null hypothesis was partially rejected, because only one all-in-one bonding system works as well as a three step bonding agent.