Received Purpose: The continuous search for better qualities and properties will never stop. As advancements in dentistry continue, new materials and techniques are being introduced to the market to meet the increasing demand for superior esthetics and best physical and mechanical properties. This study was conducted to evaluate the fracture strength of full-contour crowns of Zirconia re-enforced lithium silicate (Celtra Duo) with two different marginal designs. Deep chamfer finish line (1mm) and Featheredge finish line(0.2mm).
14 full contour monolithic Celtra Duo crowns were divided into two groups (n=7) according to each preparation design.
Group (C): samples with deep chamfer finish line design (7 samples)
Group (F): samples with feather edge finish line design (7 samples)
conclusion: The higher value of the fracture strength detected in Celtra Due crowns was with the feather edge margin design. The feather edge margin design is a promising alternative to other margin designs, as it is more conservative approach and as long as resin cement is being used as adhesive cement to increase the fracture strength and durability.