ADHESION OF CANDIDA SPECIES TO STAINLESS STEEL MICROIMPLANTS. A PRELIMINARY STUDY

Microimplants are used in orthodontics as absolute anchorage devices. Traditionally made of cobalt-chromium-molybdenum alloy, at present they are made of 316L stainless steel and titanium-aluminum-vanadium. They are flexible, easy to remove and do not accumulate bacterial plaque. A long transmucosal profile allows placing them in the infrazygomatic region and mandibular shelf. Objective: To evaluate the presences of Candida species on stainless Steel microimplants used for orthodontic treatment. Method: A cross-sectional study was conducted. Men and women aged 18 to 50 years receiving orthodontic treatment were included. The patients were instructed to rinse their mouth with 0.98% sterile saline solution before the samples were collected. Using a sterile swab, samples were collected from the microimplants and surrounding tissues, and placed in test tubes containing 1mm of saline solution. Smears were obtained from each study site, and stained with Gram and Giemsa stains. The samples were cultured in differential chromogenic medium (CHROMagar) and CHROM-Pal, and incubated at 37ºC for one week. The different species were identified according to colony color on the chromogenic medium, micromorphology in agar milk with 1% Tween-80, and carbohydrate assimilation using the Api ID 32 D system (R BioMerieux, France). The results were statistically analyzed. Results: Fifteen samples were collected from 7 patients; 40% of samples were positive for a Candida species. Region 4 (right hemimandible) showed the highest percentage of positives (50%), followed by region 1 with 33%; 14% of patients tested positive in all samples, 28% tested negative in all samples, and 57% had positive and negative samples. The presence of several species was detected, with Candida albicans being the most frequent (67%). Conclusions: Treatment with microimplants generates an oral microenvironment that favors growth of Candida species, as shown by the high percentage of screws found to be colonized by some species of Candida spp. The length of the transmucosal profile poses the need for frequent antiseptic mouth rinses in order to reduce the carriage of these microorganisms.