Introduction: A few studies investigated the numerous potential endodontic uses of CBCT, including the examination of root canal morphology and presumed that CBCT was effective for the initial identification of such morphology; moreover CBCT is a reliable method for the detection of the MB2 canal when compared with the gold standard of physical sectioning of the specimen. The aim of this study was to identify the root and canal morphology of the maxillary first molars among Malaysians analysed by cone-beam computed tomography (CBCT) images. Materials and Methods: Maxillary first (n = 421) molars from Malaysian patients (n = 241) of Malay, Chinese and Indians inceptions were examined by two Endodontists using in vivo CBCT methods. The number and configuration of roots, the number of root canals, and the canal configuration according to Vertucci’s classification were determined. Results: Single roots were not found in maxillary first molars. The incidence of fused roots was 1.995% in the first molars between mesiobuccal and distobuccal roots. In (421) 3-rooted maxillary first molars, additional canals were found in 45.6% of the mesiobuccal (MB) roots and 0% of the distobuccal (DB) roots. Bilateral symmetry of the MB roots was found in 82.36% of the first molar. Only one tooth was found to have pulp stone inside the pulp chamber. Conclusions: The root and canal configuration of a Malaysian population showed different features from those of other populations. CBCT scans can enhance the understanding of root canal anatomy, with the potential of improving the outcome of endodontic treatment.

Introduction: This study aimed to assess the effectiveness of dental plaque removal and to determine factors that could influence its efficacy when using the non-dominant hand. Methods: A quasi-experimental study was performed on a group of dental students. Dominant hands were determined using Edinburg Handedness Inventory questionnaire, and the dental plaque scores were examined using Quigley-Hein (Turesky) index. All of the participants were examined twice for dental plaque index scores. Data obtained was analyzed using a paired t-test and an independent t-test. Factors which influenced the dental plaque removal were listed and categorized accordingly. Results: A total of 62 dental undergraduates participated in the study. A high percentage of them, (71%, n = 44) were found to be right-handed. There was a significant increase in the dental plaque score for the left-handed participants, from baseline (use of the dominant hand) to follow-up appointment (after brushing their teeth with non-dominant hands) (p< 0.01). A significant change was found between the right- and left-handed participants in the first quadrant of the buccal side (p<0.05). Factors identified to be beneficial in dental plaque control were; using a mirror while brushing, extending brushing time, increasing brushing frequency, using additional tooth aids and powered toothbrushes. Conclusions: This study revealed that left-handed participants have less ability to remove dental plaque with their non-dominant hands. The right-handed participants, showed better controls in plaque removal with their non-dominant hands, compared to their left-handed peers on the buccal side of the first quadrant.