Evaluation of the accuracy of light polymerizing tray material for splinting in open tray implant impressions: An In-vitro 3D Spatial Analysis.

Aims and objective: Precise reproduction of the intra-oral spatial relationship of implants with an impression becomes the first step in achieving an accurate, passively fitting prosthesis. This in vitro study aims to compare the dimensional accuracy of dental implants in casts obtained from open tray splinted implant impression techniques using two different splinting materials. Methods and Material: A mandibular acrylic model with four implant analogues was used as a reference model. Open tray impression copings were attached to the implant analogues and were splinted using two different materials. Group I-splinted with pattern resin, sectioned and re-joined and Group II- splinted with light cure tray material. Eight polyether impressions were made for each group and poured in type IV dental stone. The casts retrieved from each group were three-dimensionally analysed using coordinate measuring machine with 0.001 mm accuracy. A one-way ANOVA and post hoc test was done to calculate the statistically significant difference between the groups. Results: The present study revealed no significant difference in the inter-implant distances obtained from pattern resin splinted group, whereas, significant difference in z-axis  was found in light polymerising tray resin splinted group when compared to the values obtained from the reference model. Conclusions: Casts obtained from splinting the impression copings using pattern resin before making implant impression were found to be more accurate than splinting with light cure tray material.