Reliability of intraoral scanning for capturing gingival morphology and color in periodontitis patients

Intraoral scanners (IOSs) can directly capture the three-dimensional (3D) morphology and color of soft tissue and dentition, but a few studies have tested the reliability of IOSs for recording gingival tissues of periodontitis patients in vivo. The aim of this study was to evaluate the reliability of intraoral scanning for recording the morphology and color of gingival tissues in the anterior teeth region of periodontitis patients. Direct and indirect digital maxillary models of ten periodontitis patients were acquired by an IOS and a conventional impression (CI), respectively. Superimposition of the digital models was performed to calculate the 3D deviation of the gingival tissues of the anterior teeth between pairwise digital models. Color values (L*a*b*) were recorded at thirteen anterior gingival sites, and the color differences (ΔE*) were calculated. Precision was analyzed using paired-samples t-test, color precision with Mann-Whitney U test, and ΔE among different points with one-way ANOVA. The IOS demonstrated a significantly lower 3D deviation (42.5 ± 17.9 μm) compared to CIs (105.3 ± 40.8 μm) (Ρ = 0.001). The overall ΔE* was 5.69 ± 2.63. The ΔE values of the gingival margins and middle gingival tissue were 6.24 ± 2.62 and 5.07 ± 2.46, respectively, and a significant difference was found (Ρ = 0.009). The ΔE* values of different points were not equal. Intraoral scanning provides a highly reliable representation of the gingival morphology of periodontitis patients. The precision of the IOS to reproduce color information of the middle gingival tissue is better than that of the gingival margins. The Chinese Clinical Trial Registry, No. ChiCTR2200058275 (04/04/2022).