Reliability and validity of intraoral photographs for orthodontic clinical judgment

Abstract Purpose To evaluate the reliability and validity of intraoral photographs for orthodontic clinical judgment in treatment planning and follow-up, compared with other standard diagnostic records. Methods A systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines and prospectively registered in International Prospective Register of Systematic Reviews (PROSPERO). Electronic searches were performed in PubMed/MEDLINE, Embase, Scopus, Web of Science, the Cochrane Library, IEEE Xplore, and PsycINFO through 15 October 2025. Studies assessing the reliability, validity, or diagnostic agreement of intraoral photographic assessments in orthodontics were included. Risk of bias was evaluated using QUADAS‑2 and ROBINS‑I. Due to heterogeneity in study designs and outcomes, a narrative synthesis was performed. Results Seven studies met the inclusion criteria. Two studies demonstrated high agreement between photographic and conventional measurements (intraclass correlation coefficients 0.90–0.999). One study reported good to excellent agreement for orthodontic index scoring, with variability across indices. Four studies assessing diagnostic performance showed agreement ranging from slight to high; however, diagnostic accuracy for specific clinical tasks did not exceed approximately 80% and was influenced by photographic conditions. Overall, risk of bias was moderate to high across studies. Conclusion Intraoral photographs may reliably support selected orthodontic measurements and may assist in the evaluation of visually assessable diagnostic features. However, diagnostic performance varies by outcome and is constrained by methodological limitations. Intraoral photographs are best used as an adjunct to, rather than a replacement for, comprehensive orthodontic diagnostic records. Trial registration PROSPERO (CRD420251024126).