Intraoral scans can be articulated in maximum intercuspal position (MIP) by using an artificial intelligence (AI) based program; however, the impact of edentulous areas on the accuracy of the MIP located using this AI-based program is unknown. The purpose of this in vitro study was to assess the impact of edentulous areas (0, 1, 2, 3, and 4 posterior mandibular teeth) on the accuracy of the MIP located using 3 intraoral scanners (IOSs) and an AI-based program. Stone casts articulated in MIP in an articulator were digitized (T710). Five groups were created: no edentulous area (Group 0) or edentulous area of 1 (Group 1), 2 (Group 2), 3 (Group 3), or 4 (Group 4) posterior mandibular teeth. A maxillary and mandibular scan were obtained from the reference casts with 3 IOSs: Primescan, Aoralscan3, and i700. The nonarticulated scans were duplicated 20 times. Six subgroups were created based on the program used to locate the MIP: 3 IOS subgroups: PrimeScan, AoralScan3, and i700 and 3 subgroups for the AI-based program (Bitefinder) (Primescan-AI-articulated, Aoralscan3-AI articulated, and i700-AI articulated) (n=10). In the Group 0-Primescan subgroup, the 10 duplicated corresponding scans were articulated by recording a bilateral occlusal record. In the Group 0-Primescan-AI articulated subgroup, the 10 duplicated corresponding scans were automatically articulated in MIP by the AI-based program. In the Group 0-Aoralscan3 and Group 0-i700 subgroups, the same procedures were completed as in the Group 0-Primescan. In the Group 0-Aoralscan3-AI articulated and Group 0-i700-AI articulated subgroups, the same procedures were accomplished as in the Group 0- Primescan-AI articulated. For the data acquisition of Groups 1, 2, 3, and 4, the right mandibular posterior teeth were removed sequentially. The same procedures were completed as in Group 0. A program (Geomagic Wrap) was selected to compute interlandmark measurements on the digitized articulated casts (control) and each articulated specimen. Two-way ANOVA and pairwise multiple comparison Tukey tests were used to analyze trueness (α=.05). The Levene and pairwise multiple comparison Wilcoxon rank tests were used to analyze precision (α=.05). Trueness and precision discrepancies were found between the groups (P<.001) and subgroups (P<.001), with a significant interaction group×subgroup (P<.001). Groups 0, 1, and 2 obtained the best trueness and precision, while Group 4 demonstrated the worst trueness and precision. Primescan and Aoralscan3 obtained better trueness than the i700. The AI-based program obtained lower MIP trueness and precision when compared with the IOSs tested. The AI-based program revealed the best MIP accuracy when articulating scans recorded by using the i700 and the worst with the Aoralscan3. Edentulous areas impacted the trueness and precision of the MIP recorded by using the IOSs or AI-based program tested. Edentulous spaces involving 1 or 2 posterior teeth did not impact the MIP accuracy. An edentulous space of 4 teeth revealed the worst accuracy values captured by using the IOSs assessed or AI-based program. The performance of the AI-based program was influenced by the IOS system used to record the nonarticulated digital scans.
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