Background. Deboning of ceramic brackets using a Er:YAG laser has become an acceptable method to facilitate the removal of such type of brackets. Therefore, research has been conducted to establish safer and more effective techniques. The pulse duration is one of the most critical parameters with respect to thermal effect on the pulp vitality.Objectives. The goal of the current research is to evaluate the thermal effect of different Er:YAG laser pulse durations in order to establish safe and effective protocols of debonding ceramic brackets.Material and Methods. The sample consisted of 45 premolars extracted for orthodontic purposes. A ceramic bracket was bonded to each tooth. The sample was divided into three groups: 15 teeth for pulse duration of 50 μs, 15 teeth for pulse duration of 100 μs, and 15 teeth for pulse duration of 300 μs. All the ceramic brackets were exposed to the Er:YAG laser for 6 s by laser scanning method, with the same air and water conditions, as well as the same pulse energy and repetition rate. The tooth temperature was monitored during debonding the brackets by a thermal camera, and the ceramic bracket was debonded after 18 s. Then, the samples were examined under a microscope to evaluate the presence of the adhesive material.Results. The results showed the absence of a statistically significant difference between the pulse duration of 50, 100 and 300 μs in relation to the rise in temperature of the tooth. However, a statistically significant difference was found in relation to the presence of adhesive materials between pulse duration 50 μs and both 100 and 300 μs, with no statistically significant difference between 100 and 300 μs.Conclusion. Within the limits of this study, both Er: YAG pulse durations of 100 and 300 μs are preferred during ceramic brackets debonding using the laser scanning method.