Methods: The veneers used were Direct Venears (DV-Edelweiss) and Novo.lign (NL-Bredent). The morphology, structure and composition of the buccal veneer surfaces were investigated by reflection light microscopy, SEM/EDX and ATR-FTIR. Surface roughness was assessed by a 3D-optical profiler, gloss by a gloss-meter, wettability by contact angle measurements with water and hardness by Knoop microhardness (n:5 per group for all tests). Statistical analysis was performed by t-test (a:0.05).
Results: NL was mainly based on PMMA matrix, whereas DV on a particle-reinforced (Al-Ba-Na-F-Si glass) aromatic dimethacrylate matrix. The surface of DV demonstrated a characteristic glossy “paint on” like morphology, easily differentiated from the typical PMMA polished surface. Although NL showed higher mean values than DV in all the roughness parameters tested (Sa, Sz, Sdr, Sci), no statistically significant differences were documented (p>0.05). Gloss values ranged from 43.8 (NL) to 39.8 GU (DV) with p>0.05. Significant differences were found in wettability (59.80 DV;53.20 NL) and KHN (63.3 DV;27.8 NL).
Conclusions: There are differences in the chemical composition, wettability and hardness between the materials tested. These differences may affect their clinical performance, especially on issues related to abrasion resistance, plaque accumulation and staining.