Clinical and radiographic assessment of peri-implant tissue changes using two different implant connections with immediate implant placement and loading. (In Vitro and In Vivo Study)

Abstract

At a time when implant placement has become the most convenient and preferred option for replacement of teeth, maintaining bone and soft tissue around the implant are of critical importance specially if in the esthetic zone. There have been many trials in the implant design and also crown abutment materials that favor stress distribution away from the crest of the implant, thus preserving the tissues around it and improving the esthetic outcome. Our study was conducted in two lines along each other, an in-vitro and an in-vivo study. The primary aim of our study was clinical, radiographic and volumetric analysis of the peri-implant tissues with two different types of implant-abutment connections: internal hex and conical connection. To check whether the conical connection preserved the peri-implant tissues better than the internal hex connection in immediately placed and loaded implants in the esthetic zone. The secondary aim was FEA and strain gauge measurements of these two types of connections (internal hex and conical tapered) with three different materials ( IPS Emax, Cubic Zirconia and Vita Enamic). To allow better understanding of the different combinations of crown materials with the proper implant-abutment connection to better choose the correct restoration for better preservation of peri-implant tissues. A three-dimensional (3D) model simulation of the implants and its components was obtained from the manufacturer and modelled in the 3D FEA software. Six different models were created according to combinations of restoration materials (LD,CZ, VE) and abutment connections (IH and CT). The hybrid abutment crowns were loaded virtually 100N vertically in the central fossa and 30⸰ oblique direction. The stress distribution in the crown, implant, abutments and surrounding bone were evaluated through the Von Mises stress analysis.