Marginal and internal adaptation of ceramic veneers fabricated using conventional intraoral scanning workflows and an integrated intraoral scanning-optical coherence tomography workflow for a subgingival preparation finish line.

OBJECTIVES: To compare marginal and internal adaptation of ceramic veneers fabricated using conventional intraoral scanning or integrated intraoral scanning-optical coherence tomography (IOS-OCT) for a subgingival preparation finish line. METHODS: A maxillary central-incisor phantom with a labial finish line 0.5 mm apical to the gingival-replica margin was digitized using i700 or Primescan IOSs with the replica absent (IOSO) or present (IOSG), or IOS-OCT with the replica present (n = 15 technical replicates per workflow). One veneer was fabricated per dataset. The outcomes were cervical and incisal absolute marginal discrepancy (AMD) and marginal gap (MG) and internal gap; cervical MG was the prespecified primary outcome. Analyses included one-way ANOVA, multiplicity-adjusted pairwise comparisons, and Welch sensitivity analyses (α=.05). RESULTS: Cervical MG differed among the workflows (adjusted P=.011). IOS-OCT exhibited a smaller cervical MG than IOSG (Primescan) only in an exploratory comparison (difference, -26.7 µm; simultaneous 95% CI, -52.2 to -1.2 µm; adjusted P=.037) and a smaller internal gap than IOSG (i700) (difference, -24.4 µm; simultaneous 95% CI, -43.9 to -4.8 µm; adjusted P=.007). Exploratory comparisons showed greater incisal AMD with IOS-OCT than with both IOSO workflows. CONCLUSIONS: Under the tested conditions, IOS-OCT exhibited a smaller internal gap than IOSG (i700), whereas a smaller cervical MG than IOSG (Primescan) was supported only by an exploratory comparison. Differences were outcome- and comparator-specific. CLINICAL SIGNIFICANCE: The integrated IOS-OCT workflow may support ceramic veneer fabrication when the labial subgingival preparation finish line is concealed; clinical effectiveness requires further investigation.