Effects of fixed orthodontic appliance on the microflora of dental plaque

This study was undertaken to elucidate the effect of fixed orthodontic appliance on the microbial composition of dental plaque and to detect any difference between the isolated microflora from different teeth before and during treatment. Twenty subjects (15 females and 5 males) between (12) and (23) years of age, participated in this study. From each subject, four swabs were collected; two in the anterior region (upper and lower central incisors) and two in the posterior region (upper and lower first molars). Bacterial examinations were performed before the beginning of the treatment and (4-6) weeks after placement of orthodontic appliances, so (160) swabs were collected. The composition of dental plaque determined was under light microscope. The statistical analysis was performed and the results showed a variety of microorganisms from supra-gingival plaque samples in pre-and during treatment fixed orthodontic patient. Changes during treatment consisted of an increase in the Peptpcocci,Klebsiella,- Streptococci, Pseudomonas and Escherichia coli in certain locations. Conversely, a decrease in the Peptostreptococci,Bacteroids,Veillonella, Staphylococci,Streptococcus mutans, Klebsella, Candida, Lactobacilli and Propeniobacterium in different locations, whereas other microorganisms and some of the above-mentioned microorganisms in certain locations showed insignificant differences. The comparison of microflora between different teeth indicated that the molars presented a significantly more microorganisms than incisors did specially in pre-treatment, whereas the upper incisor in both pre-and during treatment presented more microorganisms than lower incisor; while the lower molar exhibited more microorganisms than the upper molar particularly during treatment.