Approximately 45% of patients had at least 1 septum, and this finding emphasizes the need for the assessment of the maxillary sinuses to prevent complications.

Background and Aim: Making impression of several implants simultaneously for fabrication of dental prosthesis is challenging for many clinicians. Splinting can be performed for highly accurate impression making and better adaptation of prostheses. This study aimed to assess the effect of Impla and Duralay acrylic resin splinting materials on dimensional changes of direct implant impressions. Materials and Methods: In this in vitro experimental study, a master model was fabricated using epoxy resin. Three fixtures were vertically placed with 15mm distance from each other. Impression copingswerescrewed and splinting was performed with Impla Fix and Duralay acrylic resin separately. Fourteen impressions were made of the splints and dimensional changes were determined by measuring distances in x, y and z axes on casts using coordinate measuring machine (CMM). Data were analyzed using t-test. Results: The mean and standard deviation of change in Duralay and Impla groups were 28.078.68 and 257.39, respectively. Changes in x (P=0.746), y (P=0.772) and z (P=0.631) axes were slightly greater in use of Duralay acrylic resin but the differences were not statistically significant. Conclusion: Impla splinting material is superior to Duralay acrylic resin due to smaller dimensional changes and easy use.