The impact of microscopic access cavity preparation training on naked-eye operative skills of undergraduate dental students

Naked-eye access cavity preparation is an indispensable core skill for undergraduate dental students. Although microscopic magnification can markedly improve the quality of access cavity preparation, it remains unclear whether dedicated training in microscopic access cavity preparation can facilitate the acquisition and refinement of proficiency in naked-eye access cavity preparation. This study was therefore designed to investigate the influence of microscopic access cavity preparation training on students’ performance in naked-eye access cavity preparation. All students were randomly allocated into two groups of 35 each: the control group received conventional phantom-head access cavity preparation training, whereas the experimental group received microscope-assisted training. The 2-hour training session was conducted on the left mandibular first molar (tooth #36), followed by a practical assessment on the same tooth. Performance was independently evaluated by two experienced endodontists in accordance with the access cavity preparation scoring criteria for the national medical licensing examination. Subsequently, a questionnaire was administered to the experimental group. To ensure educational equity, the control group also received the microscope-assisted training after the assessment. The experimental group exhibited statistically significant improvements in overall access cavity preparation outcomes ( P = 0.034), with marked increases in scores for specific assessment domains, including access location, cavity form, and tooth tissue preservation ( P = 0.019). Additionally, the microscope-assisted group completed unaided access cavity preparation in significantly less time (15.16 ± 4.29 min) than the control group (17.26 ± 3.30 min; P = 0.028). Questionnaire results revealed predominantly positive student attitudes toward the microscope-assisted training, with participants recognizing its substantial benefits in enhancing operational stability, fine motor control, and understanding of dental anatomy and pulp chamber morphology during conventional naked-eye access cavity preparation. Microscope-assisted access cavity preparation training significantly improves both the quality and efficiency of unaided access cavity preparation among undergraduate dental students.