Troubleshooting with Cast Restoration

The retention of base metal crowns and noble metal crowns cemented with various luting agents is well documented. However, little emphasis was given on degree of convergence and surface area of tooth preparation.A study was planned to analyse the effect of degree of convergence & surface area of tooth preparation on retention of titanium crowns with various adhesive luting agents.45 caries free extracted human premolars were obtained & divided into 3 groups according to degree of convergence & sub divided according to type of luting agent used Light body copper band impressions were made to determine surface area. Titanium crowns were sand blasted, ultrasonically cleaned and cemented using Panavia F, Calibra and Glass Iononer Cement. Results & Discussion The result revealed that Panavia F was the best luting agent showing maximum retentive force to dislodge the Crown in vertical direction using universal tensile testing machine at a cross head speed of 1mm/min The force required to dislodge the titanium crown from the prepared tooth was maximum for Panavia F Retentive force values drastically reduced as the as the degree of convergence increased.