A COMPARATIVE EVALUATION OF THE ACCURACY OF MASTER CAST FABRICATED BY FOUR DIFFERENT MODIFICATIONS OF IMPLANT LEVEL OPEN TRAY TRANSFER IMPRESSION TECHNIQUE FOR SINGLE–TOOTH REPLACEMENT: AN IN–VITRO STUDY

Dr. Reena Ravi; Dr. Divya Dahiya; Dr. Priya Nagar; Dr. Aman Dahiya

Volume : IX, Issue : VIII, August - 2019

A COMPARATIVE EVALUATION OF THE ACCURACY OF MASTER CAST FABRICATED BY FOUR DIFFERENT MODIFICATIONS OF IMPLANT LEVEL OPEN TRAY TRANSFER IMPRESSION TECHNIQUE FOR SINGLE–TOOTH REPLACEMENT: AN IN–VITRO STUDY

Dr. Reena Ravi, Dr. Divya Dahiya, Dr. Priya Nagar, Dr. Aman Dahiya

Abstract :

Statement of problem: Minor rotation of impression coping secured during implant impression is an avoidable error that needs to be minimized to ensure precise positioning of implant analog in master cast. Purpose: The aim of this study was to check and compare the accuracy of master casts obtained by modification of impression coping by using four different techniques and to compare these master casts with reference model. Methods & material: A total of 80 master casts were made (20 for each group). Group I samples were prepared with original virgin surface impression copings, Group II samples with impression copings surface modified by sandblasting with 50 μm aluminum oxide powder. Group III included samples which were faicated with impression copings modified by coating of adhesive only. Group IV samples which with impression copings sandblasted and coated with adhesive. Profile projector (Dynascan PT 300E) was used to evaluate the rotational and positional accuracy of the internal hexagon implant analog by compå Molar Implant Angle (MIA) and Premolar Implant Angle (PIA) of test samples with reference model. Result: Statistical comparisons were made using ANOVA test, post hoc test, and unpaired t‑test that showed non–significant results. Sandblasted with adhesive coated impression coping produced the master casts accuracy closest to the reference resin model. Conclusion: Sandblasted and adhesive coated impression copings showed minimum amount of variation followed by sandblasted and adhesive coated impression copings.