Interaction of universal dentin bonding systems of non carious cervical lesions: a randomized clinical controlled trial and analyses of anti-proteolytic activity by in situ zymography and in vitro characterization of physical mechanical properties

Abstract

Based on the current diversity of available technologies in formulations and strategies of bonding systems, their potential overpass the adhesive property. The versatility of their application is also a relevant component. In this context, the universal dentin systems offer these possibilities based on distinct monomeric bases and solvents. Despite of the studies that emphasize 10-MDP as a stable monomer, other bases have been employed, even with a poor investigations regarding to adhesive and antienzymatic potential. Among the scenarios of clinical challenges, the Erosive Tooth Wear (ETW) is of great prevalence, requiring the use of adhesive systems in the case of restoratives procedures. The aim of the study will be to evaluate the clinical performance, anti-proteolytic activity and physical-mechanical properties of universal adhesives applied to non-carious cervical lesions. The clinical stage will involve an interventional, randomized and prospective, double-blinded, split-mouth controlled clinical study. The main study factors will be the adhesive systems (Adper Single Bond Universal - SU and BeautiBond Xtreme - BX) and evaluation time (initial - 7 days, 6 months, 12 months and 18 months). The main outcome will be the retention of the restorations and their clinical performance (modified USPHS and FDI analyses). The secondary outcomes will be: level of dentin hypersensitivity (VAS), quality of life analysis (OHIP-14), BEWE index (Basic Erosive Wear Examination), and degree of sclerotic dentin. Statistical analysis of qualitative data will be performed using the Friedman test, followed by the Tukey test if there is a significant difference between the groups (p<0.05). In the in vitro stage, the study will be parallel and blinded. In addition to the adhesive systems tested, the study will also involve the substrate factor: sound (S; stored in artificial saliva), eroded (E; 0.1% citric acid - 90 s/ 4 cycles/ 5 days) and artificially hypermineralized dentin (H; remineralizing solution - 14 days). For this, 135 specimens of bovine dentin (6 x 6 mm) will be cut, polished and prepared according to the type of substrate. The substrates will initially be characterized in terms of their molecular profile in FTIR (n=5). The remaining specimens will be randomized, treated with adhesive systems and evaluated regarding the enzymatic activity by in situ zymography (ZM; n=5), surface microhardness (SM; n=5), contact angle (wettability - W; n=5) and surface roughness (SR; n=5). The homogeneity and normality of the data will be evaluated and statistical analysis will be performed using the ANOVA and Tukey tests (p<0.05). It is expected that the compreehension of the related properties allows the of future formulation of experimental and patent.