Comparison between students' self-assessment, and visual and digital assessment techniques in dental anatomy wax-up grading.

Introduction: Digital technology has the potential to provide a bias-free evaluation instrument for practical examination grading. E4D Compare software was designed for teaching institutions to allow comparison between scanned models prepared by students and master models prepared by instructors. The aim of this study was to determine the tolerance value for the E4D compare software (E4D Technologies LLC, Richardson, TX, USA) that provides scores comparable with faculty grades for wax-ups #23 and #19. Additionally, this study sought to assess the correlation between students' self-assessments, visual and digital grades and the reliability of the software.

Methods: Student wax-ups (n = 112) were uploaded into the software and then compared with faculty-generated master wax-ups. Digital grading was performed at tolerances 200-800 μm in 50 μm increments and was repeated twice.

Results: A tolerance of 350 μm was the closest to faculty grades for #23 and 500 μm was the closest for #19. Visual and digital grades showed moderate to high correlation for both wax-ups. Correlations between students' self-assessments and visual and digital grades improved with #19 versus #23. A near-perfect correlation was found between grades at the first and second digital grading sessions.

Conclusions: The tolerance that closely matches faculty grades differs according to the tooth type. The software provided consistent grades and correlated well with faculty grades. Students' self-assessment skills improved as they proceeded throughout the course. Further studies are necessary to ascertain the role of the software in improving students' self-assessment skills.