The findings of this study suggest an increased oxidative stress and imbalance in the antioxidant defense system in biological fluids of patients with OLP. These findings may reflect the disease phenomenon of OLP rather than a causal effect and their role in pathogenesis and transformation of OLP to cancer, if any, needs further elucidation.

Problem-oriented learning is an effective method of learning that increases students' learning motivation, improves the relationship amongst students and results in open-minded discussions. In this study, a new problem-oriented pharmacobiochemistry course related to 'oxidative metabolism of drugs by cytochrome P450 (CYP450) systems' was designed. Students were divided into seven groups. Three keywords related to drug interaction through CYP450 were provided to each group in order for them to conduct research on the information given. After 1 month, the groups attended a session under the supervision of a tutor to solve a simulated problem case that was designed using the keywords. At the end of the integrated course, a multiple-choice examination was given. The success rate of 76 students who attended the course was found to be significantly higher than the success rate of the students who received the lecture-based course only (P < 0.0001). A questionnaire containing 20 items (Cronbach's alpha: 0.92) was administered to the students to learn about their perception regarding this educational model. The questionnaire was evaluated using the Likert scale. Student feedback was very positive, with fourteen answers rated as 'agree' and the remaining six rated as 'strongly agree'. Students thought that the problem-oriented model was very enjoyable and useful in regard to dental education. Based on these results, we conclude that this course model may help achieve an integrated curriculum for dental school programmes.