Planimetric quantification of plaque in patients with multibracket appliances using an intraoral scanner - proof-of-concept.

OBJECTIVES: This proof-of-concept study aimed to evaluate whether disclosed dental plaque can be reliably visualized and quantified using an intraoral scanner in patients with multibracket (MB) appliances, despite potential imaging artefacts caused by metallic brackets. MATERIALS AND METHODS: Twenty patients (mean age: 17.0 ± 2.1 years) with fixed MB (Mini Sprint® II or SPEED brackets) underwent 3D-intraoral scans before (T1) and after (T2) bracket debonding. Plaque was visualized using a disclosing agent and quantified planimetrically on selected Ramfjord teeth (FDI 16, 21, 24, 36, 41, 44) using standardized image processing. Five image sets per tooth were analysed to compare plaque coverage (P%) under various conditions: with brackets, after debonding, with masked bracket areas and with the masked areas transferred onto surfaces after debonding, and with only the exposed surface considered. Statistical analyses included t-tests and Bland-Altman plots. RESULTS: Highest P% values were found with brackets in situ (49.4 ± 8.9 P%), followed by values obtained after bracket debonding (34.0 ± 7.1 P%). After masking bracket areas, plaque levels approximated those seen after debonding (29.8 ± 7.0 vs. 34.0 ± 7.1 P%; p < .001). No significant difference was observed between bracket types. Reliable plaque quantification was achieved when bracket areas were masked in both scan sets. CONCLUSIONS: Intraoral scans enable valid planimetric plaque quantification in patients with MB, especially when metallic bracket areas are masked during analysis. CLINICAL RELEVANCE: Digital intraoral scans, combined with plaque disclosing agents, offer a reproducible and objective method for assessing plaque levels in orthodontic patients. This approach may support individualized hygiene monitoring and patient education during fixed appliance therapy.