Clinical trial design and baseline output

Introduction: Multi-Mode (MM) are contemporary generation of simplified adhesives indicated for use under different application strategies. Objectives: Describing the randomized clinical trial (RCT) design and baseline output of MM adhesives applied by Self-Etch (SE; with non-etched or etched enamel) and Etch-and-Rinse (ER) strategies, analysing NCCL restorations for two-years (2016-2018). Materials and Methods: Prospective, double blind RCT approved by UFP-Ethics Committee, National-Clinical-Trials-Ethics-Committee (NCTEC-20150305), Infarmed (EC/011/2015), NCT02698371, in 38 patients with 210 restorations (Admira Fusion®) randomly allocated in six groups (Adhesive's; Strategies) of 35 restorations: G1-Control (Futurabond®DC;SE); G2-Control (Futurabond®DC;SE etched-enamel); G3 (Futurabond®U;ER); G4-(Futurabond®U;SE); G5 (Adhese®Universal;ER); G6 (Adhese®Universal;SE). RCT design included NCCL characteristics. All restorations evaluated (success rate-efficacy) at baseline (one-month after restoration) by three calibrated examiners (ICC≥0.952) using USPHS and FDI criteria. Statistical analysis with nonparametric tests (alpha=0.05). Results: Median age: 55.5years, 21(55.3%) male; 210 NCCL in 176(83.8%) pre-molars and 34(16.2%) molar teeth (p=0.252).; NCCL Dentin sclerosis categories (Chi2-test;p=0.353): 146(69.5%) One, 35(16.7%) Two, 8(3.8%) Three and 21(10%) Four; Median NCCL estimated volume of 30.3(18.0-49.1)mm3; NCCL-geometry (p=0.903): 84(40%) Acute, 60(28.6%) Severe and 60(31.4%) Obtuse. At baseline all restorations showed 100% success rates. Discussion: Efficacy of different adhesion strategies are usually evaluated in NCCL restorations. No differences were found in NCCL characteristics by RCT groups. RCT designs should include NCCL features when evaluating clinical performance of adhesive's strategies. Conclusions: NCCL characteristics were similar in RCT groups. MM adhesives with different strategies showed baseline excellent performance. Clinical Implications:Restoration evaluation at mean/long term are mandatory to determine clinical performance of MM adhesion strategies. Keywords: Multi-mode, self-etch, universal adhesive, NCCL, RCT, composite restorations