Evaluation of Effect of Etching Duration and Loading Conditions on Fracture Resistance of Ceramic Veneers Prepared on Permanent Maxillary Central Incisors-An Experimental Study

Background: Using ceramic veneers for restoration of non-esthetic teeth has magnified with the increased demand of patient awareness. Several factors affect prolonged prognosis of ceramic veneers. This study will help to comparatively evaluate the effect of etching duration and loading conditions on the resistance to fracture of ceramic veneers. Objectives: To evaluate the fracture resistance of "Lithium disilicate ceramic veneers" at an angle of 60 degrees after exposure to 5% hydrofluoric acid for 20 secs and 40 secs then comparative evaluation of the same. Methodology: Study comprises of 12 samples of freshly extracted permanent maxillary central incisors followed by mounting them in self polymerizing acrylic resin, and preparing butt joint design tooth preparation. Tooth preparation followed by making its impression using polyvinyl siloxane impression material with a customized tray and poured with die stone. Wax pattern will be fabricated over it for fabrication of veneers. After fabrication, etchant application will be done for a specific period of 20 sec & 40 sec over the prepared tooth followed by applying bonding agent. Cementation procedure will be followed. The mounted teeth will be exposed to a load at an angulation of 60 degrees simulating intercostal movement and will be evaluated and compared for resistance to fracture by using Universal Testing Machine. Expected results: This study will help the dentists to assess better fracture resistance of ceramic veneers. Conclusion: With the help of this study dentists can use effectiveness of optimum etching duration on ceramic veneers.