This study was done to evaluate the thread design of conventional implant and indigenous implant in implant retained auricular prosthesis- its implant thread shape, diameter and length on stress distribution using Finite element analysis. This study follows to determine the primary stability of the craniofacial auricular implant in the fresh goat maxilla using Resonancefrequency analysis method.
Both the groups were loaded with a force of vertical load of 10N and a second moment of 100 Nmm applied in the centre of the cranial and caudal part in the temporal region independely and with two implants connected by gold casting bar. The results were analyzed and interpreted
using ANSYS Software. The data’s was obtained, tabulated and statistical analysis was done.
Within the limitations of this study, supports the following that FEA has been used extensively in the prediction of performance of craniofacial auricular implant systems. In the modeling, some assumptions greatly affect the predictive accuracy of the FEA model. These include assumptions involving model geometry, material properties, applied boundary conditions, and the bone-implant interface. To achieve more realistic models, advance 3D White light scanner can be used to model bone geometry in greater details. In addition, modeling of the bone-implant interface should incorporate the actual osseointegration contact area in cortical bone as well as 3-dimensional bone contact.
Load transmission and resultant stress distribution at the bone-implant interface and with two implants connected by gold bar has been the subject of FEA studies. Factors that influence load transfer include the type of loading, implant and prosthesis material properties, implant length, implant diameter, implant thread shape and nature of the bone-implant interface.
Of these biomechanical factors, implant length, diameter and shape can be modified easily in the implant design. In Finite element analysis, with the increase in craniofacial implant length in Group I and Group II from 3mm, 4mm, and 6mm with constant diameter 3.75mm for V-shape thread design and Buttress shape thread design implant, resulted in reduction in the stress for Buttress shape thread. There was no effect on diameter of the flange when the length of the craniofacial implant increased. When two implants connected by bar, the stress distribution is very minimal.
By Resonance frequency analysis, in fresh goat skull, the readings were found to be statistically higher ISQ values in buttress-shape thread when compared to V-shape thread. RFA is related to the stability of the implant-bone interface. The time and bone quality interaction has significant influence on ISQ values. More studies are required about RFA in clinical case of craniofacial auricular implant systems.
Future scope needs to be on research and development coupled with controlled, prospective clinical studies to guide the clinician in near future. This studies further needs to be studied clinically
