Accuracy of Intraoral Scan Post-processing Methods: A Clinical Trial

In the last decade, progressive developments in computer hardware, software, manufacturing technologies, and dental materials consistently enhanced the use of digital technologies in dentistry. Traditional prosthodontic techniques have relied on manual fabrication processes, which often resulted in challenges such as suboptimal prosthesis fit, compromised occlusal stability, and limited customization options. However, the advent of 3D printing technology has revolutionized the field, offering new possibilities for patient-specific prosthodontic rehabilitation.

An accurate maxillomandibular relationship between the maxillary and mandibular casts is fundamental to prosthodontic practice. In the integration of intraoral scanners (IOSs) for different dental interventions, the accuracy of the digitizing methods recording the maxillomandibular relationship is similarly essential. The maxillomandibular relationship accuracy recorded by using IOSs has been analyzed in various in vitro and clinical studies.

Intraoral digital scans are recorded in an unload condition, with the mouth open, while acquiring the maxillary and the mandibular intraoral scans. This condition changes when capturing the virtual occlusal records at maximum intercuspation position (MIP). Occlusal collisions are caused by the tooth location discrepancy resulting from the periodontal ligament plasticity between the recording of the intraoral digital scans and the virtual occlusal records, as well as from the intraoral scanning distortion and alignment procedures.

Artificial intelligence driven program software and occlusal collisions or mesh interpenetrations tools have been proposed to improve the maxillomandibular relationship of the scanned models. The software programs of the IOSs can automatically eliminate the occlusal collisions present in virtual articulated casts. Similarly, dental computer-aided design (CAD) programs can automatically detect and eliminate occlusal collisions among the articulated intraoral digital scans imported. However, the effect of the occlusal collision corrections performed by using IOSs or CAD programs on the occlusal adjustment of the restorations is unknown.