Influence of ambient light conditions on intraoral scanning: A systematic review.

Purpose: To systematically assess the influence of ambient light on the accuracy and scanning time of intraoral scanning.

Study selection: The present systematic review (CRD 42022346672) was registered at the International Prospective Register of Systematic Reviews (PROSPERO) and was performed based on the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020. Electronic searches were conducted using PubMed, Web of Science, and EMBASE, complemented by gray literature, references, and citations of the included studies. The primary outcome was accuracy, and the scanning time was a secondary outcome. Owing to the high heterogeneity, the pooled data were analyzed descriptively.

Results: Six in vitro and two in vivo experiments were performed. Three in vitro studies reported both the accuracy and scanning time of the intraoral scans, whereas the remaining studies exclusively evaluated the accuracy. The studies mainly investigated the influence of illumination levels (0-11000 lux) on intraoral scanning. Intraoral scans revealed optimal accuracy at 1000-lux illumination for complete-arch dentition scans, whereas the influence of illumination levels on 4-unit or shorter scans was not clinically significant. The intraoral scans obtained using confocal microscopy were less affected by the illumination levels than those obtained using the active triangulation technique. Furthermore, the scanning time tended to increase with increasing illumination.

Conclusions: Evidently from the limited number of studies conducted, ambient light illumination had considerable influence on the accuracy and scanning time of intraoral scanning, which appeared to be related to the scanning range and imaging technology.