الفهرس | Only 14 pages are availabe for public view |
Abstract This study was designed to compare the fracture resistance and shade accuracy of two types of zirconia crown fabricated by two different techniques Bilayered CAD- on technique (CAD/CAM-fabricated zirconia core veneered with CAD/CAM-fabricated lithium-disilicate glass-ceramic veneering material) and CAD/CAM zirconia monolithic full contouring technique supported by zirconia implant abutment and titanium implant abutment. Twenty four titanium implants with a diameter of 3.7 mm and a length of 11.5 mm will be embedded with student acrylic model to replace the missing maxillary first premolar guided by the manufacturer’s instructions. This study is divided into two group according to the types of abutments that were used (Titanium straight abutments, Zirconia straight abutments) twelve for each. The abutments were 4.5 mm diameter, the abutment screws were tightened to 35 N-cm with a hex driver and a calibrated torque driver. Each group will be divided in to two subgroups according to the type of zirconia crown used, Bilayered CAD- on crown and CAD/CAM monoblock crown. Two types of zirconia crown were cemented to the abutments using the Variolink cement as a try-in past. Aspectrophotometer was used to measure the shade accuracy and the universal testing machine for measuring the fracture resistance through: 1- Bilayered CAD- on crowns on titanium and zirconia dental implant abutments. 2- Full contoured CAD /CAM monoblock crowns on titanium and zirconia dental implant abutments. 77. |