effect of digital bite registration condition and scanner type on the accuracy of 3d printed occlusal splints

Objective: the present study aimed to evaluate the accuracy of occlusal splints created at different bite registration conditions using two intraoral scanners.methods: dental arches were mounted in the maximum intercuspation position and scanned using trios 3 and medit i700 scanners under three conditions: closed mouth position, and open bite to 4 mm with or without bite registration material. eight splints were printed for each bite registration mode and scanner type (total=48), using a phrozen 3d printer. the splints were placed on the model and scanned using a desktop scanner. the scans were superimposed on the digital file of the designed splint. the root mean square (rms) deviation was calculated to represent the discrepancy between the designed and printed splints. the distance between the splint and the mandibular teeth was also measured. data analysis was performed using a two-way anova (α=0.05).results: bite registration mode did not affect the rms and the distance between the splint and the mandibular teeth (p>0.05). the scanner type did not influence the rms values and posterior and total distance between the splint and the mandibular teeth (p>0.05). however, using the trios 3 scanner led to a significantly greater distance between the splint and the mandibular teeth in the anterior region compared to that of the medit i700 scanner (p=0.016).conclusions: bite registration condition did not affect the accuracy of occlusal splints. splints fabricated with the medit i700 scanner had a better anterior fit than those scanned with the trios 3 scanner.