STRAIN GAUGE ANALYSIS OF TOOTH-IMPLANT-SUPPORTED FDP WITH NON-RIGID CONNECTORS USING DIFFERENT IMPLANT-ABUTMENT CONNECTIONS: INVITRO

Abstract

Purpose: To evaluate and compare the strains generated around tooth and implant supported FDPs, including a non-rigid connector, arranged in a linear configuration.Problem Statement: clinical evidence about the connection between the tooth and implant in a fixed dental prosthesis is limited. Certain clinical situations mandate such combination however the prognosis of such treatment is of concern. Methods: Two models were fabricated to mimic missing lower second premolar, the anterior abutment was a natural tooth and the posterior one abutment was an implant attached to its corresponding abutment. 3-unit FDPs with a non-rigid connector and of 8 mm pontic mesio-distal width were constructed, alternating the location of the non-rigid connector at either abutments. Four strain gauges were attached mesially, distally, buccally and lingually to natural tooth and implant. Uniform static axial load of 300 N was applied to the central fossa of the FDP units parallel to the long axis. Strain (µm) induced at both the implant and tooth were recorded and analyzed. Results: Lower mean strains were induced around the tooth on placing the non-rigid connector at the implant side and using cone connection, while around the implant insignificant difference was found. Lower mean strains were induced around both tooth and implant on placing the non-rigid connector at the tooth side and using cone connection. Conclusion: connecting teeth -to-implants must be limited to cases with only one missing tooth. Placing the non-rigid connection at implant side and using cone connection provide favorable strain distribution.