Clinical Performance of Posterior Resin Composite Restorations Placed by Undergraduate Students and Postgraduate Trainees: A Retrospective Study Using USPHS and FDI Criteria

This retrospective observational study was conducted at the Department of Pediatric Dentistry of a university-based dental faculty to compare the clinical performance of posterior resin composite restorations placed by undergraduate dental students and postgraduate specialty trainees.

Dental records of pediatric patients aged 6 to 13 years who received posterior resin composite restorations on primary or permanent first and second molars were retrospectively reviewed. A total of 200 restorations were included in the study, of which 100 were placed by undergraduate students and 100 by postgraduate trainees. All restorations were placed using the same microhybrid resin composite material as part of routine clinical care.

Restorations were excluded if they were placed by operators outside the defined study groups, if materials other than resin composite were used, if follow-up duration was less than three months, or if the restorations were placed on teeth other than posterior molars. Clinical evaluations were performed during routine follow-up or concurrent dental treatment visits.

All restorations were assessed by a blinded examiner using two standardized evaluation systems: the modified United States Public Health Service (USPHS-Ryge) criteria and the FDI World Dental Federation (FDI-Hickel) criteria. Esthetic, functional, and biological parameters were evaluated clinically, and radiographic assessments were performed when clinically indicated. Under the USPHS criteria, restorations were categorized as acceptable or unacceptable. According to the FDI criteria, scores of 1-2 were considered successful, score 3 clinically acceptable, and scores of 4-5 unsuccessful.

Recorded variables included operator group, restoration type (one-, two-, or three-surface), follow-up duration, tooth type (primary or permanent), patient age, and endodontic treatment history. Clinical outcomes were compared between operator groups and across follow-up intervals to evaluate the influence of operator experience and time on restoration performance.