RESUMEN
Dental education is incorporating computer-assisted design/computer-assisted manufacturing (CAD/CAM) into patient care delivery. The aim of this study was to determine if lean production methods applied to the preclinical phase of dental education would reduce the students' time (efficiency) to complete CAD/CAM indirect restorations (CAD/CAM IR) without compromising the desired quality of the CAD/CAM tooth preparations (effectiveness). In 2016, all third-year students at one U.S. dental school were randomly assigned to control and research groups (approximately 33 per group). The control group was taught using existing methods, while the course was redesigned to incorporate lean methods for the research group. Cycle times of the CAD/CAM IR process for both groups were collected and statistically analyzed to compare the effectiveness of the redesign. Standardized grading forms and tools were used to assess the quality of the CAD/CAM tooth preparations. The research group demonstrated significantly faster preparation times with both crowns and onlays (p<0.05) than the control group. The research group also produced CAD/CAM crown and onlay designs at a significantly faster pace than the control group (p<0.05). There was no significant difference between the control and research groups associated with the scanning process times (p>0.05) nor in the quality of the CAD/CAM tooth preparations (p>0.05). This study demonstrated that lean methods applied to pedagogy significantly decreased preparation and design times in a CAD/CAM restorative dentistry course without compromising the quality of the CAD/CAM tooth preparations.