A Pilot Comparison of Torque Delivery to Implant Assembly Screws Using Two Different Mechanical Devices

Objectives: This pilot study examined the reliability by which connectors in dental implant component assemblies can achieve adequate joint preload using two different types of mechanical torque controlling devices. Methods: Twenty implant fixtures were set in dental stone within two experimental platforms. Ten corresponding abutments were attached to half these fixtures with titanium center screws using a “clutch“ type mechanical wrench driver. Ten other abutments were joined using a “spring resistance” type mechanical driver. Each center screw was then untightened, measuring the amount of release torque required, with a centripedal torque dynamometer. Results: The mean of the release torque using the clutch type wrench was 11.9 Ncm (+/-1.42). The mean of the spring-loaded wrench was 13.09 Ncm (+/-1.75). A statistical analysis (Student-t test) was performed determining that the spring loaded torque wrench is significantly different in torque delivery (p=.05). CONCLUSION: The clinical integrity of a dental implant prosthesis is closely related to the performance of its mechanically joined components. Variations in the protocol for attaching these components may have an effect on fastener performance. In this study the wrench applying continual force maintained greater torque.