Accuracy of different splint methods for implant impression making at different times

Abstract

History and goal: One of the most common problems of implant impression making with impression copings is the possibility of their movements in the impression material. Splinting techniques and time of splinting are important factors in overcoming the polymerization shrinkage and increasing the accuracy of implant impression. The aim of this study was to evaluate the accuracy of different splint methods for implant making at different times.

Materials and methods: In this experimental in vitro study, using a 2-piece index of metal and acrylic model illustrator of the patient's jaw with 2 implant analogues embeded, splints of impression copings were made of autopolymerized acrylic resin (GC Pattern Resin LS, GC America Inc , USA) at different times and Open Tray impression approach was performed. From acrylic model , 36 casts were fabricated .After scanning the casts, we compared the impression accuracy in 3 groups by measuring the distance between the outer portions of the scan bodies screwed on implant analogues inside the cast coordinate software Exocad©: 1- Splinting Impression Copings with autopolymerized acrylic resin and impression making immediately after seting time (4 minutes) 2- Splinted and impression procedure have done after 17 minutes with splint section and reconnection. 3- Splint was sectioned and reconnected after 24 hours, then impression was made. The results were analyzed by SPSS 17 software and Kruskal-Wallis test.

Results: The mean distance measured in impression group 1 was 19.14 ± 0.029 mm, which was significantly less than the main model. In groups two and three were 19.15 ± 0.039 and 19.159 ± 0.033 mm, respectively, which were not significantly different from the main model. The mean distance measured in 3 impression technique was similar. Conclusion: There was no significant difference in the accuracy of impression making in the three splint methods at different times.