THE EFFECT OF DIFFERENT ABUTMENT FINISH LINE CONFIGURATION ON STRESS DISTRIBUTION OF IMPLANT SUPPORTED ZIRCONIA FIXED PARTIAL DENTURE

Purpose: to study the influence of different abutment finish line configuration on stress distribution of implant supported fixed partial denture.
Materials& Methods: Two endo-osseous screw vent implants for 2nd premolar and 2nd molar were chosen and placed parallel to each other. After resin model construction, Implants were attached to the corresponding abutments group according to the finish line configuration of the abutments. Group A: standard abutment with circular contour, Group B: anatomical abutment with anatomical contour. The fixed partial denture was designed with a flat area on the occlusal surface to accommodate for the loading pin tip each time. Strain gauges were adhered to four different sites (buccal, lingual, mesial and distal) and a force of 200N over 30 seconds duration and maintained for 30 seconds also. Then forces were removed and residual strains were released for 2 minutes.
Results: One-way ANOVA used to compare between different abutment finish line configuration and teeth for mean Strain (µm/m) and total strain followed by Tukey’s post-hoc test for pairwise comparison. Significant level set at p < 0.05.The results revealed that all types of abutments have a certain level of misfit, which resulted in measurable strains. Significant difference was found between the different groups of the finish line configuration (standard & anatomical).
Conclusion: Difference in abutment finish line configuration may affect the stress pattern induced around dental implants.
Clinical significant: implant abutment with anatomical finish line configuration is a preferred selection for better stress distribution.