Consistency of Intraoral-Scanner-Derived Occlusal Contact Distance Maps Between Centric Relation and Maximal...

Background/Objectives: Intraoral scanners (IOSs) are increasingly used for digital occlusal evaluation; however, the interpretation of IOS-derived occlusal contact distance visualizations remains influenced by registration and alignment factors. This study aimed to compare occlusal contact distance distributions obtained with an intraoral scanner between maximal intercuspation (MIP) and centric relation (CR) under controlled scanning conditions. Methods: Fifteen participants underwent standardized digital bite registration in both mandibular positions. Only scans exhibiting interocclusal overlap ≤ 0.1 mm were included. Occlusal contact distance maps were exported, standardized, and quantified using an open-source image segmentation workflow to calculate the relative area of distance-based contact categories. Paired statistical analyses were performed to compare CR and MIP distributions. Results: No statistically significant differences were observed in the distribution of occlusal contact distance categories between centric relation and maximal intercuspation (p > 0.05). The proportion of very close contact distances remained low in both positions (approximately 6-9%), while moderately close and distant contact distances predominated across all scans, indicating comparable distance-based occlusal visualization patterns under controlled acquisition conditions. Conclusions: Under controlled scanning conditions, IOS-derived occlusal contact distance maps exhibited comparable distribution patterns between centric relation and maximal intercuspation. These findings support the use of intraoral scanning for comparative evaluation of occlusal contact distance distributions, while highlighting the importance of interpreting IOS-derived visualizations within their methodological and technical limitations.