Examining the ability of artificial intelligence-driven occlusal contact adjustment to improve virtual occlusal record trueness for implant restorations: An in vitro study.

OBJECTIVES: This in vitro study evaluated the influence of artificial intelligence-driven occlusal contact adjustment (AI-OCA) on the trueness of virtual occlusal records (VORs) acquired using two intraoral scanner (IOS) systems (TRIOS4 [TR4] and TRIOS5 [TR5]). The tests were conducted in models representing either mandibular free-end edentulism or single molar defects requiring implant rehabilitation. METHODS: A typodont model of a partially edentulous mandible (missing teeth: #35-37, #46) with four implants was mounted on a semi-adjustable articulator. Twelve stainless-steel spheres were fixed to the maxillary and mandibular arches as fiducial reference points. Reference datasets were obtained using a high-precision laboratory scanner. Each IOS performed 10 scans of both arches, and VORs were generated via bilateral buccal scans. Each dataset was duplicated and processed with or without AI-OCA, yielding four experimental groups: TR4 No-Adj, TR4 Adj, TR5 No-Adj, and TR5 Adj. Six inter-arch distances (D16-46, D13-43, D23-33, D25-35, D26-36, and D27-37) were calculated based on distances between corresponding sphere centers using reverse-engineering software. Deviations between the IOS-derived measurements and the reference data were analyzed in terms of both signed and unsigned linear discrepancies. Data were analyzed using non-parametric statistical tests due to non-normal data distribution (Shapiro-Wilk, P < 0.001). Trueness was reported as median (interquartile range) and was assessed using Wilcoxon signed-rank tests (α = 0.05). RESULTS: AI-OCA significantly affected VOR trueness in a position-dependent manner. For TR5, occlusal adjustment enhanced trueness at D25-35, D26-36, and D27-37 (P < 0.01), while TR4 showed improvement only at D25-35 (P < 0.01). However, both scanners showed reduced trueness at D16-46 following AI-OCA (P < 0.01). CONCLUSIONS: The effect of AI-OCA on VOR trueness varied according to the scanner type and the span of edentulism. Results from both scanners for single posterior molar defects were more accurate when AI-OCA was not used. TR5 performed better in assessing VOR trueness for implant-supported restorations in free-end scenarios. CLINICAL SIGNIFICANCE: The clinical effectiveness of AI-OCA use is dependent on both the specific IOS used and the anatomical extent of edentulism. While beneficial in certain implant scenarios, AI-OCA may compromise trueness when applied to limited-span defects such as single posterior tooth loss.