Purpose: To evaluate the effect of six scan patterns on the accuracy and speed of digital impressions with two different intraoral scanners for complete-arch implant rehabilitation.
Materials and methods: A master model containing six parallelly placed implant analogs was fabricated, and six scan bodies were connected to the analogs. Reference scan was obtained with a laboratory scanner. Test scans were obtained by intraoral scanning with six scan patterns using 3Shape TRIOS 3 and Carestream CS 3600 intraoral scanners. Scanning time was recorded. Trueness and precision were assessed with an inspection software. Two-way analysis of variance (ANOVA) was performed to examine the effect of scan pattern, scanner, and their interaction on accuracy and scanning time. Differences between the six scan patterns with each scanner were tested by one-way ANOVA. Differences between the two scanners were evaluated by t test. The level of significance was set at α = .05.
Results: For trueness, the effects of scanner, scan pattern, and their interaction were significantly different in both linear and angular discrepancy. For precision, the scanner and scan pattern each had a significant effect on linear discrepancy independently, while their interaction did not. Only the effects of scanners were significantly different in angular discrepancy. For each of the two scanners, significant differences were detected in accuracy and speed between the patterns.
Conclusion: Scan pattern significantly influenced the accuracy and speed of digital impressions for complete-arch implant rehabilitation.