Statement of the problem: The advancing computer-aided design/computer-aided manufacturing (CAD/CAM) technology has changed the fabrication protocols of fixed prosthodontic restorations dramatically in the last 25 years. Beside the dental CAD programs open source nondental software have been utilized for prosthodontic purposes. Despite the progress in technology, varying accuracy and precision rates, and lack of standardized workflows are still challenging issues.
Objective: No study to the authors' knowledge evaluated the precision of the manually used processing tools of CAD softwares despite the necessity of utilizing multiple tools to design a restoration, thus it was aimed to evaluate the processing discrepancies of smoothing procedures.
Materials & Methods: A virtual working cast of a maxilla with six teeth prepared with shoulder finish lines containing irregularities up to 50µm were composed. The irregularities were smoothed manually using the 'brush' tools in the 'sculpt' mode of the DWOS, Blender and Meshmixer softwares. Smoothed virtual working casts were superimposed with the reference virtual working cast.
Results: The results of Turkey HSD test revealed significant differences
between Meshmixer and Blender (P=0.000), and Meshmixer and DWOS
(P=0.000), no significance was found between DWOS and Blender values
Conclusion: The results of the study pointed out that smoothing procedure may lead to significant differences in discrepancy values, nondental CAD
software can perform smoothing with less discrepancy thus, commencing further studies including multiple users and softwares for the evaluation of different design tools seems imperative.