Accuracy and patient satisfaction of intraoral scanner in preschool-aged children: a combined in vivo and in vitro study

Objectives This study aims to evaluate the accuracy of intraoral scanner (IOS) in both intraoral and extraoral settings within primary dentition, as well as patient satisfaction among preschool-aged children. Methods Forty-one preschool-aged children underwent intraoral scanning with the iTero Element 2 scanner and conventional alginate impressions (CI). Resulting plaster models were digitized via both IOS and a desktop scanner. To assess precision, one plaster model was scanned ten times with the IOS. Accuracy was measured via Geomagic Control 2022, which evaluated root mean square (RMS) deviation and intra-arch linear distances. A validated questionnaire was used to access the degree of comfort and preference between IOS and CI. Statistical analyses included paired t-tests, repeated-measures ANOVA, Friedman tests and Wilcoxon signed-rank tests, with statistical significance set at P < 0.05. Results The trueness of the intraoral scan was 0.1282 ± 0.0230 mm (maxilla) and 0.1341 ± 0.0255 mm (mandible), whereas the extraoral scan showed significantly higher trueness (0.0399 ± 0.0059 mm in the maxilla, 0.0430 ± 0.0087 mm in the mandible) ( P < 0.001). The precision was 0.0347 ± 0.0066 mm for the maxilla and 0.0358 ± 0.0063 mm for the mandible. Most intra-arch distances showed no significant variation across scanning methods. The questionnaire responses favored IOS, with significantly greater comfort and preference ( P = 0.014), despite some perceptions of scanner bulkiness. Conclusions The IOS delivers high accuracy for both intraoral and extraoral scans in primary dentition and is well accepted by preschool children, showing potential for wider application in pediatric dentistry.