Aim: Limited data are available on the fitting properties of prototyped occlusal appliances. The aim of the present study was to assess the fitting of prototyped splints digitally designed with different offset values and generated with two different biocompatible resins.
Materials and methods: Ten dental digital models were included, and occlusal splints were designed with different offset values (0.0, 0.05, 0.10, 0.15, 0.20, and 0.25 mm). Each splint was 3D printed using two different biocompatible resins, and the gap between the splint and the teeth was recorded by placing impression material. A specific 3D technology was used to assess the gap volume between the splint and the teeth and to calculate the Euclidean distance between the surface points of two digital models, with and without the gap volume.
Results: The splints with a 0.20-mm offset value showed smaller gap volume and deviation analysis values compared with those with offset values of 0.15 and 0.25 mm (P < 0.05). These results were consistent with both types of biocompatible resins used. For each offset value tested, the gap volume and deviation value analysis did not significantly differ between the splints printed with the two different resins.
Conclusion: According to the present findings, the 0.20-mm offset value would be the best choice when digitally designing occlusal appliances.
Keywords: CAD/CAM; digital dentistry; digital orthodontics; occlusal appliance; splint; 3D printing.