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 per- formed on a group of dental students. Dominant hands were determined using Edinburg Handedness Inventory ques- tionnaire, 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 inde- pendent 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