PURPOSE: This study used cone-beam computed tomography (CBCT) to characterize mandibular molar root and canal morphology and its variability in Belgian and Chilean population samples. MATERIALS AND METHODS: We analyzed the CBCT images of 515 mandibular molars (257 from Belgium and 258 from Chile). Molars meeting the inclusion criteria were analyzed to determine (1) the number of roots; (2) the root canal configuration; (3) the presence of a curved canal in the cross-sectional image of the distal root in the mandibular first molar and (4) the presence of a C-shaped canal in the second mandibular molar. A descriptive analysis was performed. The association between national origin and the presence of a curved or C-shaped canal was evaluated using the chi-squared test. RESULTS: The most common configurations in the mesial root of both molars were type V and type III. In the distal root, type I canal configuration was the most common. Curvature in the cross-sectional image was found in 25% of the distal canals of the mandibular first molars in the Belgian population, compared to 11% in the Chilean population. The prevalence of C-shaped canals was 10% or less in both populations. CONCLUSION: In cases of unclear or complex root and canal morphology in the mandibular molars, CBCT imaging might assist endodontic specialists in making an accurate diagnosis and in treatment planning.
Belgium ; Cone-Beam Computed Tomography* ; Dental Pulp Cavity ; Diagnosis ; Molar* ; Prevalence ; Specialization

Introduction: The use of chemicals in teaching laboratories exposes students and laboratory staff to risk arising from hazardous chemicals. Accidents related to poor management and handling of chemicals have been reported in teaching laboratories. Good implementation of occupational safety and health (OSH) in organisation that has implemented OSH-Management System (OSH-MS) plays an important role in reducing accidents at the workplace. The aim of this study is to assess the level of knowledge, attitude and practice (KAP) related to the OSH aspect in chemical handling among workers in OSH-MS certified and non-certified public universities in Malaysia. Method: This is a cross-sectional survey involving laboratory workers in four public universities in Malaysia. A total of 120 laboratory staff were recruited and data on KAP was collected using self-administered questionnaires disseminated physically and via online platforms. Items in the questionnaire were adapted from previous studies and published guidelines. Data obtained were entered into statistical software for analysis. Results: About 76% of workers in certified universities have high knowledge, 94% have a positive attitude, and 88% have good practice in OSH. In non-certified universities, 70% have high knowledge, 97.1% have a positive attitude and 81.4% have good practice in OSH. Good practice level was significantly higher in certified universities. Knowledge, in general, was associated with younger age and higher education level while attitude was linked to gender. Conclusion: There were higher percentages of good OSH practice among laboratory workers in OSH-MS certified universities. Structured and systematic OSH governance can facilitate better OSH practice and implementation in certified public universities.