Faculty of Dental Medicine, Boys, Cairo Al-Azhar University

Microbial and periodontal changes associated with conventional versus self ligating brackets.

Protocol submitted in partial fulfillment for the requirements of Master Degree in Orthodontics

Accumulation of biofilm on the tooth surfaces is associated with increased levels of oral streptococcus mutans and lactobacilli, which have been proved to be responsible for the onset of enamel demineralization and periodontal disease.

It has been shown that fixed appliance provides large number of retentive areas for plaque accumulation and impedes oral hygiene.

Three methods are currently used to connect the arch wire to the brackets, which are : ligation with stainless steel ligatures , using elastomeric ligatures, and the self-ligating brackets. , Each of these method has it's advantages and disadvantages, concerning the biofilm retention and the level of microorganisms. , Orthodontic treatment with conventional brackets my presents some periodontal changes caused by difficulty in oral hygiene maintenance, greater accumulation and qualitative alteration of plaque. Thus, in order to control oral hygiene and plaque level during fixed appliance therapy, manufacturers introduced self-ligating brackets (SLBs) which have been claimed to provide better oral hygiene and less plaque accumulation, because of fewer retentive sites for microbial colonization; without the need for stainless steel and elastomeric ligature. Clinically, the side effects of fixed orthodontic treatment, such as the qualitative bacterial shift, are manifested as plaque associated gingivitis, an increase in pocket probing depth (PPD), and bleeding on probing.