Problem-based learning versus a traditional educational methodology: a comparison of preclinical and clinical periodontics performance.

To evaluate efficacy of a problem-based learning (PBL) pedagogy in preclinical and clinical teaching, test scores of 234 undergraduate dental students from the conventionally taught classes of 2003 and 2004 were compared with scores of 274 dental students from the PBL classes of 2005 and 2006. Although the groups' means were close together, t-test analysis of scores revealed that PBL students performed significantly better than traditional (TRAD) students on midterm (p=.0001) and final (p=.015) examinations taken on student partner/mock patients. ANOVA comparing the classes with each other showed significant differences for the midterm and final, but not for the clinical examination. Further multiple comparison tests (Tukey HSD) for the midterm and final revealed that differences specifically reflected superior performance of PBL classes against one of the TRAD classes (2004). There was no difference in performance between PBL (n=134) and TRAD (n=233) students on examinations taken with actual clinical patients who were undergoing nonsurgical periodontal treatment. Over a two-year period, PBL students rated their program instructors at a mean of 4.41 on a Likert-type scale of 1 (not helpful) to 5 (outstanding). The program provides a PBL model for teaching preclinical and clinical skills supported by a four-year evaluation of manual skills outcomes.