Effect of antagonist arch on precision and trueness of digital maxillomandibular relation in partially edentulous cases using five different intraoral scanners

AIM: The study evaluated the trueness and precision of maxillomandibular relation records in intraoral scans of partially edentulous cases using dentate and edentulous arch antagonists. MATERIALS AND METHODS: Three 3D-printed models were prepared: one maxillary and one mandibular partially edentulous model and a mandibular dentate model. The partially edentulous models included two dental implants each (Bone Level RC) in the edentulous molar region. Edentulous antagonist (models 1 and 2) and dentate antagonist (models 1 and 3) groups were analyzed separately. Precision spheres were placed on each model to evaluate interocclusal distances. Reference scans were acquired by the industrial scanner (Nikon Altera). Separate model scans and interocclusal records were acquired using five intraoral scanners: Primescan, Trios 3, Trios 4, Carestream 3600, and Medit i500. Statistical analysis included Shapiro-Wilk normality tests, Mann-Whitney Wilcoxon, or Student t tests (P ≤ 0.05). RESULTS: Concerning the effect of the opposing arch (dentate antagonist vs edentulous antagonists) regarding trueness, none of the tested scanners was statistically different, while precision was statistically different for all scanners, except for Primescan (P > 0.05). Trueness and precision varied across scanners. With respect to trueness for dentate antagonists, significant differences were noted for more than half of the scanner comparisons, while Medit i500 vs Trios 3 and Trios 4, Primescan vs Trios 3, and Trios 3 vs Trios 4 remained insignificant (P > 0.05). For edentulous antagonists, significant differences in trueness were noted for most scanner comparisons, except for Primescan vs Trios 3, Primescan vs Trios 4, and Trios 3 vs Trios 4 (P > 0.05). Concerning precision, scanner comparisons for both dentate antagonists and edentulous antagonists showed significant differences, except for Primescan vs Trios 3 in the AE-group (P > 0.05). CONCLUSIONS: Dentate and edentulous antagonist arches affect precision in intraoral scans of partially edentulous jaws but do not influence trueness. (Int J Comput Dent 2026;29(1):-172; doi: 10.3290/j.ijcd.b6524367).