The effect of orthodontic appliances on the distribution of Candida and plaque in adolescents.

The site prevalence and intra-oral density of Candidal organisms may be increased by local factors including prostheses. However, whether significant changes in Candidal carriage occurs with denture wearing is not clearly established. This study employed the imprint culture technique to assess the effects of fixed and removable orthodontic appliances on oral carriage, site prevalence and intra-oral density of Candida in adolescents. Moreover, alterations in plaque distribution were measured. Groups of 12-16 year olds without or wearing fixed and removable appliances were studied. Imprint cultures were taken from six intra-oral sites and colony counts recorded after 48 hours incubation on selective media. Plaque scores were recorded from non-appliance and removable appliance wearers. The prevalence of Candidal carriage in the groups was not significantly different being 46 per cent of non-appliance, 51 per cent of fixed appliance and 52 per cent of removable appliance wearers. However, the prevalence of Candidal recovery at some sites and Candidal densities at all sites were significantly increased in both fixed and removable appliance wearers. Thus orthodontic appliances may predispose to Candidal proliferation in oral carriers. However, the results do not permit the conclusion that appliances may change non-carriers of Candida to carriers. Plaque distribution was significantly altered in removable appliance wearers when compared with non-appliance wearers as a result of increases in palatal plaque scores. These findings again emphasize the particular need for oral hygiene instruction in patients wearing appliances or partial prostheses.