Physical and biological properties of experimental self-etching adhesive systems
cytotoxicity, experimental adhesive system and Flexural resistance
Objective: To evaluate the Residual Monomer Concentration (CMR), Flexural Strength (RF), modulus of elasticity (ME), cytotoxicity and bond strength (RU) of GDMA-P formulated experimental adhesives (AE). Methodology: AE were divided into 9 groups, according to the following parameters: a)% monomeric mass of GDMA-P / HEMA / UDMA (10/30/30, 20/30/20 and 30/30/10) ; mol% of photoinitiators CQ / BAPO / EDMAB / DH (1.0 / 0.0 / 1.0 / 0.2, 0.0 / 1.0 / 0.0 / 0.2; 0.5 / 5 / 1.0 / 0.2) with solvent ethanol and water (1: 1). For cytotoxicity, NIH-3T3 cells and the MTT Assay and Alamar Blue (n = 8) assays were used. For RF and ME, the method described in ISO 4049 (n = 7) was followed. To measure CMR, 54 third molars will be used to obtain a flat area of dentin (n = 6), which will receive the adhesive systems and, after 24 hours, the CMR will be read in an ultra-absorption chromatography (UPLC) apparatus. For UK, the occlusal face of 36 third molars will be sanded by exposing dentin. On dentin (n = 5), adhesive systems will be applied and photoactivated. The UK will be measured in a universal testing machine. Statistical analysis was performed with two-way ANOVA and post Tukey test (p <0.05). Results: for RF, 10% of GDMA-P presented differences between the photoinitiators, being the BAPO group the highest RF. The BAPO + CQ mixture allowed a higher RF value for the 20% and 30% concentrations. For ME, 30% GDMA-P was the only one to present significant difference, being the BAPO + CQ group the highest value. For the% reduction of Alamar Blue, between the concentrations 10%, 20% and 30% there was no difference. Among the photoinitiators, CQ and BAPO, alone, presented better values for 30% and CQ + BAPO for the 20% concentration. For% cell viability through MTT Assay, there was no difference between photoinitiators and% GDMA-P. For CRM and UK, we still have the results.