Effectiveness of Problem-Based Learning in Dental Education: A Scoping Review

Problem-based learning (PBL) is a student-centred, self-directed learning approach that has been widely adopted in medical education. Although many studies have investigated the effectiveness of PBL, few have synthesised the existing evidence. The purpose of this scoping review was to explore the characteristics of PBL applied in dental education, particularly comparing its effectiveness with other pedagogical approaches through Kirkpatrick's four-level evaluation model.

The authors applied the Arksey and O'Malley framework to undertake a scoping review. The search was conducted on 31 December 2024 in PubMed, Web of Science, EBSCO, and other databases, including all English-language publications from January 1990 to December 2024 with no restrictions on study design or country of origin. Outcomes were classified using Kirkpatrick's four-level model (Reaction, Learning, Behaviour, Results). Methodological quality was assessed using the Medical Education Research Study Quality Instrument (MERSQI). The review protocol was registered on the Open Science Framework (OSF).

A systematic search identified 2 754 records. After deduplication and screening, 245 papers underwent full-text evaluation, and 106 studies involving 15 675 students were included. Hybrid PBL (hPBL) was the most frequently adopted strategy (57.5%), followed by modified PBL (mPBL, 22.6%) and traditional PBL (tPBL, 17.0%). Of 256 individual outcome measures synthesised, 62.1% were at the reaction level, 30.9% at the learning level, and only 7.0% at the behaviour and results levels combined. PBL consistently enhanced student satisfaction, with 100% of satisfaction outcomes (20 of 20) favouring PBL and reaction-level evaluations showing an 86.8% superiority rate. At the learning level, 69.6% of outcomes significantly favoured PBL, particularly in clinical reasoning and long-term knowledge retention; 26.6% showed no significant difference; and 3.8% favoured non-PBL approaches. Among PBL strategies, mPBL demonstrated the highest learning-level superiority rate (78.6%), followed by tPBL (70.0%) and hPBL (63.4%). The mean MERSQI score was 9.42 out of 18 (SD = 1.93), reflecting generally limited methodological quality.

A pronounced satisfaction-performance disconnect was identified: An 86.8% reaction superiority rate contrasted with a 69.6% learning superiority rate-a 17.2 percentage-point gap. Comparator-stratified analysis revealed that single-group studies reported higher reaction superiority (90.7%) than studies with control groups (82.2%), whereas at the learning level this gap largely disappeared (70.8% vs. 69.1%). Nearly half (49.7%) of all reaction-level outcomes relied on vague or unstandardised constructs. Over half of included studies (51.9%) evaluated only a single Kirkpatrick level, predominantly reaction-only assessments, precluding within-study linkages between satisfaction, knowledge acquisition, and clinical behaviour change.

PBL consistently enhanced student satisfaction and preference. Its impact on academic performance was less definitive, with many comparative studies showing no significant difference on standardised examinations when PBL was compared with traditional methods. However, PBL demonstrated clear advantages in applied clinical competencies, long-term knowledge retention, and professional practice outcomes. Modified PBL showed the highest learning-level superiority rates, suggesting that enhancing PBL with targeted pedagogical innovations may yield greater gains than hybridisation with lectures alone. Future research should prioritise comparative studies with robust designs, longitudinal outcome tracking, and assessments aligned with PBL's problem-solving objectives.