This prospective cohort study evaluates dental students' self-assessment of clinical endodontic performance and compares it with independent evaluations conducted in a dental education clinical setting. Endodontic treatments are performed by undergraduate dental students using two distinct rotary file systems selected according to routine clinical practice. Students' self-assessments are prospectively collected using a structured questionnaire and compared with evaluations performed by two experienced evaluators with access to clinical and radiographic information, considered the reference standard, as well as by two different experienced evaluators using radiographic information only. Secondary analyses examine whether assessment outcomes differ according to the rotary file system used. The null hypothesis is that there is no difference between dental students' self-assessments and reference standard evaluations of endodontic treatment quality, and that assessment outcomes do not differ according to the rotary file system used.

This prospective cohort observational study examines dental students' self-assessment of clinical endodontic performance in a dental education clinical setting and compares these assessments with independent evaluations. Endodontic treatments are performed by undergraduate dental students as part of routine clinical practice under standard supervision. Treatments are carried out using one of two distinct rotary file systems selected according to routine clinical practice, without assignment by the study protocol.

Following completion of each endodontic treatment, operators prospectively complete a structured self-assessment questionnaire evaluating the quality of their clinical performance. These self-assessments are compared with evaluations performed by experienced external evaluators. Two experienced evaluators assess each case using both clinical and radiographic information and serve as the reference standard, while two different experienced evaluators perform an assessment based on radiographic information only.

The primary objective is to evaluate the agreement between dental students' self-assessments and the reference standard evaluation of endodontic treatment quality. Secondary objectives include assessment of agreement between radiographic-only and reference standard evaluations, as well as examination of whether assessment outcomes differ according to the rotary file system used across operator self-assessments and independent evaluations.

Inclusion Criteria:

1. Healthy patients or with a controlled systemic condition
2. 18 Years and older
3. Completion and acceptance of a patient consent form for the study
4. Patient in need of an initial endodontic treatment of an upper or lower molar

Exclusion Criteria:

1. Existence of a systemic disease or usage of drugs that makes the patient unfit to undergo endodontic treatment by students in an Undergraduate Clinic.
2. Teeth with previous endodontic treatment
3. Teeth with doubtful prognosis - unrestorable
4. Teeth with severe periodontal damage
5. Alcohol or drug use
6. Pregnancy or breastfeeding

Adult patients requiring initial endodontic treatment of an upper or lower molar and deemed fit to undergo endodontic treatment performed by dental students in the undergraduate dental clinic of the Aristotle University of Thessaloniki.