Accuracy and reproducibility of dental measurements on tomographic digital models: a systematic review and meta-analysis

Objectives: The aim of this systematic review with meta-analysis was to assess the accuracy and reproducibility of dental measurements obtained from digital study models generated from CBCT compared with those acquired from plaster models. Methods: The electronic databases Cochrane Library, Medline (via PubMed), Scopus, VHL, Web of Science, and System for Information on Grey Literature in Europe were screened to identify articles from 1998 until February 2016. The inclusion criteria were: prospective and retrospective clinical trials in humans; validation and/or comparison articles of dental study models obtained from CBCT and plaster models; and articles that used dental linear measurements as an assessment tool. The methodological quality of the studies was carried out by Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. A meta-analysis was performed to validate all comparative measurements. Results: The databases search identified a total of 3160 items and 554 duplicates were excluded. After reading titles and abstracts, 12 articles were selected. Five articles were included after reading in full. The methodological quality obtained through QUADAS-2 was poor to moderate. In the meta-analysis, there were statistical differences between the mesiodistal widths of mandibular incisors, maxillary canines and premolars, and overall Bolton analysis. Therefore, the measurements considered accurate were maxillary and mandibular crowding, intermolar width and mesiodistal width of maxillary incisors, mandibular canines and premolars, in both arches for molars. Conclusions: Digital models obtained from CBCT were not accurate for all measures assessed. The differences were clinically acceptable for all dental linear measurements, except for maxillary arch perimeter. Digital models are reproducible for all measurements when intraexaminer assessment is considered and need improvement in interexaminer evaluation.