Workflow Comparison of Stereolithography With Computer Assisted Design – Computer Aided Manufactured Provisional Crowns

Objectives: To determine the effectiveness, feasibility, and workflow of stereolithography (3-D printing), CAD-CAM and traditional methods such as Integrity® in fabricating provisional crowns for clinical use.
Methods: Thirty-six provisionals were made from twelve all-porcelain preparations on mandibular first molars using Typodont teeth. Three methods of fabricating provisional crowns were completed for each of these teeth, including fused deposition modeling 3-D printing, milled CAD/CAM restorations, and traditional Integrity® methods. Each step in the above sequence was timed and recorded. Modifications to improve marginal adaptation were made to each provisional based on initial marginal gap size, and this time was also recorded.
Results: The average workflow for the 3-D printing method, per tooth, was 80.82 min, which included only 17.38 min of active time. This active time is similar to the workflow for Integrity® provisionalization, which averaged 19.19 min per tooth, including fabrication and modification. Fabrication and modification of CAD-CAM provisionals involved 32.4 min of total active time, versus inactive time spent of 10.97 min. Inactive time for 3-D printing far exceeded CAD-CAM, at an average of 64.23 min per tooth, including printing and removal of structural material. Unpaired t-test showed statistical significance between modification times of CAD-CAM and 3-D printed provisionals (p<0.001), as well as between Integrity® and 3-D printed crowns (p<0.0001). However, there is no statistical difference between recorded times for Integrity® and CAD-CAM modifications.
Conclusions: 3-D provisionalization is significantly more time consuming than traditional Integrity® methods. Modification is more complicated and requires additional time. 3-D printing maintains a similar timeline to CAD-CAM and is a worthwhile pursuit when utilized with appropriate dental materials.