Assessing the feasibility and accuracy of digitizing edentulous jaws

Background. Despite the accuracy of intraoral scanners (IOSs) in producing single-unit scans and the possibility of generating complete dentures digitally, little is known about their feasibility and accuracy in digitizing edentulous jaws. The purpose of this in vitro investigation was to evaluate the feasibility and accuracy of digitizing edentulous jaw models with IOSs. Methods. The authors used an industrial laser scanner (reference scanner) and four IOSs to digitize two representative edentulous jaw models. They loaded the data sets obtained into three-dimensional evaluation software, superimposed the data sets and compared them for accuracy. The authors used a one-way analysis of variance to compute differences within groups (precision), as well as to compare values with those of the reference scanner (trueness) (statistical significance, P < .05). Results. Mean trueness values ranged from 44.1 to 591.8 micrometers. Data analysis yielded statistically significant differences in trueness between all scanners (P < .05). Mean precision values ranged from 21.6 to 698.0 mu m. The study results showed statistically significant differences in precision between all scanners (P < .05), except for the CEREC AC Bluecam (Sirona, Bensheim, Germany) and the zfx IntraScan (manufactured by MHT Italy, Negrar, Italy/MHT Optic Research, Niederhasli, Switzerland; distributed by Zfx, Dachau, Germany) (P > .05). Conclusions. Digitizing edentulous jaw models with the use of IOSs appears to be feasible, although the accuracy of the scanners differs significantly. The results of this study showed that only one scanner was sufficiently accurate to warrant further intraoral investigations. Further enhancements are necessary to recommend these IOSs for this particular indication. Practical Implications. On the basis of the results of this study, the authors cannot recommend these four IOSs for digitization of edentulous jaws in vivo.