Changes in the supragingival microbiota surrounding brackets of upper central incisors during orthodontic treatment

Abstract

Objective. The aim of this study was to determine how fixed orthodontic appliances affect microbiota of supragingival plaque over 5 months. Materials and methods. Twenty individuals of Scandinavian origin, aged 10–16 years, were included. All subjects were fitted with fixed orthodontic appliances in both the maxillary and mandibular tooth arches. Pooled supragingival plaque samples from the labial surface of the two maxillary central incisors were collected before bonding (T1) and afterwards at 4 weeks (T2), 3 months (T3) and 5 months (T4). The plaque index (PI) was recorded for each sampling. The gingival status was documented at T1 and T4 by using clinical photographs. Plaque microbiota was identified using the Human Oral Microbe Identification Microarray (HOMIM). Results. Increased plaque levels were recorded after bonding, however the increase was not significant. The prevalence of gingivitis at the maxillary central incisors increased from 25% at T1 to 74% at T4. No significant changes of the plaque microbiota from the sample area were detected during the 5-month period. Trends toward a microbiota containing more periodontitis- and caries-associated bacteria were detected. Conclusions. Although trends toward a microbiota containing more periodontitis- and caries-associated bacteria were detected, the changes were not severe enough to be significant. Treatment with fixed orthodontics does not necessarily shift the microbiota to a more pathogenic composition.