Evaluation Of Dimensional Accuracy Of The Implant Impression In Angled Implant With Varying Subgingival Depth” - An In Vitro Study

Background: Prosthesis misfit can cause both mechanical as well as biologic complications because of the ankylotic nature of the implant osseointegration. Complications may include screw fracture, screw loosening, failure of osseointegration and marginal discrepancy leading to plaque accumulation. The key to a passive fit is to make accurate impressions. Objective: Was to evaluate the dimensional accuracy of the implant impression in angled implant with varying subgingival depth. The study compared two different impression techniques i.e. open tray without splinting the impression copings and open tray with splinting the impression copings with a self-curing acrylic resin. Material and Methods: An aluminium model with three implants was fabricated. Central implant was perpendicular and the two lateral implants were 100 and 200 angulated. The vertical positions were different among the thee implants (3.65mm, 2.145mm 1.24mm). Twenty impressions were made using two impression techniques: a) open tray with splinting the impression copings with self-curing acrylic resin b) open tray without splinting. A coordinate measurement machine was used to measure the depth and the inter-implant distance. Results: There was a statistically significant difference in splinted and non-splinted groups from the original model (P<0.05). The splinting method of impression has lesser distortion values than the non-splinted one. Student's t test showed that the difference between the splinted and non-splinted groups was not statistically significant. (P>0.05). Conclusion: The best method when impressions of multiple implants with different angulations and subgingival depths are to be made, splinting the impression copings with a self-curing resin would result in improved accuracy