Background <p>This research investigated the effectiveness of a structured three-attempt formative assessment model combined with instructor feedback in improving clinical competency among first-semester dental assistant diploma students.</p> Methods <p>Ten dental assistant students underwent repeated assessment attempts across eight operative and endodontic procedures during the Fall 2023 semester of the Dental Assistant Diploma program. After each attempt, students were given performance feedback reinforcing elements they performed well, and guiding their improvement in areas that were less well executed. Outcomes across the three attempts were then compared to determine if repeated feedback was associated with improved performance over time.</p> Results <p>Student progress with this structured feedback approach was associated with significant and consistent improvement of performance scores across the three assessments (F = 577.74; <i>p</i> &lt; 0.000), along with universally high logbook grades across students and a 100% pass rate in the final competency exam. Statistical analysis revealed a strong correlation (Pearson’s <i>r</i> = 0.94, <i>p</i> &lt; 0.000) between logbook scores and final competency exam scores, which is notable given these two assessment types were conducted by independent examiners.</p> Conclusions <p>These findings suggest that structured feedback-driven assessment plays a pivotal role in competency-based education for dental assistants. In addition, this research highlights specific design elements that may be fundamental in the success of such an approach.</p>