Effect of TiN coating of abutment screw on detorque force / 대한치과보철학회지

ABSTRACT

PURPOSE: The aim of this study is to evaluate the effect of TiN coating of abutment screw on the unscrewing torque. MATERIAL AND METHODS: Titanium and Gold-Tite abutment screws were classified into two groups, Group A and C respectively, as control groups. Titanium abutment screws with TiN coatings were also classified into two groups, Group B and D, as experimental ones. Group A and B were tightened to 20 Ncm input torque, and Group C and D were tightened to 32 Ncm torque. Detorque values were measured with digital torque gauge during repeated closing and opening experiment. RESULTS: Abutment screws with TiN coating (Group B and D) showed statistically significant higher mean detorque values than those of Group A and C. DISSCUSION: Physical properties of TiN coating, such as low friction coefficient, high hardness and wear resistance, might contribute to higher detorque values. CONCLUSION: It is suggested that TiN coating of abutment screw help to reduce the risk of screw loosening and improve the stability of screw joint.