Purpose: This study compared the accuracy of the fitting and occlusal surfaces of digitally printed and conventionally fabricated occlusal appliances.
Materials and Methods: Ten intraoral scans (TRIOS 3, 3Shape) of zirconia master models (Zr MM) were sent to a commercial dental laboratory to design and fabricate Digital Occlusal Appliances (DOAs) using a 3-D printing technology. Ten alginate impressions of the same zirconia models were utilized by the commercial dental laboratory to fabricate Ten Conventional Occlusal Appliances (COAs). The lab technician was instructed not to carry out any adjustments following manufacturing of the appliances. Benchtop scans were obtained of the DOAs and COAs fitting and occlusal surfaces to determine the accuracy compared to the benchtop scan of the Zr MM. In addition, linear measurements of the scans were compared for both DOAs and COAs.
Results: A statistically significant difference in the individual tooth fit was observed; DOAs showed significantly higher conformity of the shapes of the fitting surfaces of selected teeth (#18, #16, #13, #23, #26, and #28). However, COAs showed significantly lower linear distortions in the arch level in most dimensions. DOAs on the other hand, showed significant distortions in linear measurements, especially in mediolateral dimensions. This mediolateral distortion in the DOAs was found to be positively correlated with increased arch length in these appliances.
Conclusion: While DOAs can reproduce fitting surfaces of individual teeth at significantly higher accuracy than COAs, substantial linear distortions were observed in DOAs in the arch level, especially mediolaterally.Dentistry, Faculty ofGraduat
