Comparative Evaluation of Various Splinting Materials on the Positional Accuracy of Multiple Transmucosal Abutments using Open Tray Impression Technique: An In Vitro study

AIM OF THE STUDY: The aim of this study is to compare and evaluate various splinting materials on the positional accuracy of multiple transmucosal abutments, using open tray technique for the All-on-four implant protocol. MATERIALS AND METHODOLOGY: An acrylic edentulous maxillary reference model was fabricated with four implants placed according to the All-On-Four protocol. For two straight anterior implants, two straight transmucosal abutments and for two distally placed posterior implants, 30˚ angled transmucosal abutments were used. A total of 20 impression were made with open tray splinted with flowable composite(n=10) (GROUP A) and open tray splinted with GC Unifast TRAD (GROUP B) using polyether impression material. A Coordinate Measuring Machine was used to measure the linear (x and y axes) and angular (z axis) measurements for the reference acrylic model and the casts obtained from closed tray and non-splinted open tray groups. The linear and angular displacement values of the casts were compared with the values obtained from the reference acrylic model and were subjected to statistical analyses (p=0.05). RESULT: There was no significant difference in the linear and rotational discrepancies between both the splinted open tray(Group A and Group B) and the reference acrylic model. There was statistically significant difference between both the splinted open tray on comparison of the distance between the reference point and the abutment 4 in y axis. CONCLUSION: There was no significant difference in the accuracy of the casts obtained using the splinted open tray impression techniques and the reference acrylic model using the All-On-Four protocol within the study's limitations