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Objective:The objective of the study was to determine the sites of plaque accumulation and to compare the plaque accumulated with metal, ceramic and self-ligating orthodontic brackets in order to clarify which bracket type had a higher plaque retaining capacity. Materials and methods:The study was done on 30 subjects who were scheduled for fixed orthodontic treatment including extraction of four premolars. Mesh-backed edgewise metal brackets, ceramic and self-ligating brackets were bonded to the premolars to be extracted using composite (Transbond XT, 3M). Teeth were extracted at 1, 2 and 3 weeks after bracket bonding. Plaque attached to the buccal surfaces was stained using plaque disclosing agent. (Alpha plac). The teeth were then immersed in fixative containing 4% formaldehyde and 1% glutaraldehyde in phosphate buffer for 24 hours, followed by 0.1 M phosphate buffer for 12 hours. The specimens were then mounted on aluminum stubs and sputter coated with gold prior to SEM examination. Results:The results showed that increased retention of plaque in ceramic brackets ligated with elastomeric ring followed by metal and comparatively less in self-ligating brackets at the base of the brackets. Conclusion:This study highlights that higher retention of plaque in ceramic brackets ligated with elastomeric ring followed with metal brackets ligated with steel ligatures and comparatively less plaque retention in self-ligating brackets. Excess composite around the bracket base is the critical site of plaque accumulation associated with fixed appliances due to its rough surface texture.