Microbial contamination profile on esthetic elastomeric ligatures through the checkerboard DNA-DNA hybridization technique : A randomized split-mouth study.

OBJECTIVE: The aim of this study is to assess the microbial contamination of three different brands of esthetic elastomeric ligatures. MATERIALS AND METHODS: Different brands of esthetic ligatures (Unistick Pearl [American Orthodontics, Sheboygan, WI, USA], Power Sticks Pearl [Ortho Technology, Tampa, FL, USA], and Ease [Obscure, 3M Unitek, Monrovia, CA, USA]) were randomly assigned to permanent canines of 25 patients (aged 11-18 years) undergoing corrective orthodontic treatment. After 30 days, the ligatures were removed, processed, and the biofilm composition was analyzed by checkerboard DNA-DNA hybridization for 40 bacterial species. The microbiological data were analyzed using a nonparametric mixed model. RESULTS: The ligatures presented intense microbial contamination after 30 days, but no statistically significant differences were observed among the three groups (p > 0.05). The levels of the evaluated individual species and proportions of the microbial complexes showed no statistically significant differences among the ligature groups (p > 0.05). CONCLUSIONS: Esthetic elastomeric ligatures became multicolonized by several bacterial species after 30 days of exposure to the oral cavity. However, no relevant differences were observed among the biofilm composition formed on the different ligature brands.

Polymorphisms in FGF3, FGF10, and FGF13 May Contribute to the Presence of Temporomandibular Disorders in Patients Who Required Orthognathic Surgery.

BACKGROUND: To evaluate whether genetic polymorphisms in FGF3, FGF10, and FGF13 are associated with temporomandibular disorders (TMD) in patients that presented dentofacial deformities requiring orthognathic surgery. MATERIAL AND METHODS: The sample comprised a total of 113 patients of both sexes. The diagnosis of TMD was performed before orthognathic surgery between Research Diagnostic Criteria for Temporomandibular Disorders (RDC-TMD). According to the TMD assessment, the patients were divided into 3 major groups: myofascial pain, articular disc displacements and other TMD conditions (arthralgia, arthritis, and arthrosis). Genomic DNA was collected from saliva samples and genetic polymorphisms in FGF3 (rs1893047 and rs7932320), FGF10 (rs900379) and FGF13 (rs5931572 and rs5974804) were analyzed by real-time polymerase chain reactions. The association between the TMD conditions and the genetic polymorphisms assessed were analyzed by Poisson Regression. The model was calculated on bivariate and adjusted by sex. The established alpha was 5%. Data were analyzed by using SPSS software (IBM, Armonk, NY). RESULTS: The genetic polymorphisms rs7932320 in FGF3 (P < 0.001) and rs900379 in FGF10 (P < 0.05) were associated with the presence of muscle disorder. The genetic polymorphisms rs1893047 in FGF3, rs900379 in FGF10, and rs5974804 and rs5931572 in FGF13, were associated with the presence of disk displacement (P < 0.05). The genetic polymorphisms rs1893047 and rs7932320 in FGF3, rs900379 in FGF10, and rs900379 in FGF10 were associated with other TMD conditions (P < 0.05). CONCLUSION: Genetic polymorphisms in FGF3, FGF10, and FGF13 genes were associated with temporomandibular disorders in a population with dentofacial deformities.

Molecular detection of Aggregatibacter actinomycetemcomitans on metallic brackets by the checkerboard DNA-DNA hybridization technique.

INTRODUCTION: The purpose of this randomized clinical study was to evaluate the presence of the periodontal pathogen Aggregatibacter actinomycetemcomitans on metallic brackets and the effectiveness of a 0.12% chlorhexidine digluconate mouthwash in inhibiting this microorganism. METHODS: The study involved 35 patients of both sexes having orthodontic treatment with fixed appliances between the ages of 14 and 22 years, randomized into 2 groups: experimental (n = 17) and control (n = 18). Two new metallic brackets were placed on the patients' premolars, and the subjects rinsed with a solution of 0.12% chlorhexidine digluconate or a placebo solution twice a week for 30 days. After that, the brackets were removed and underwent microbiologic analysis with the checkerboard DNA-DNA hybridization technique. Data were analyzed by using the Student t, Fisher exact, and Mann-Whitney tests at the significance level of 5%. RESULTS: The results showed that A actinomycetemcomitans was present in all brackets from the subjects in the control group vs 83% of the subjects who rinsed with chlorhexidine digluconate (P <0.0001). There were also significantly lower levels of this species in the chlorhexidine digluconate group compared with the control group (P = 0.0003). CONCLUSIONS: We concluded that 0.12% chlorhexidine digluconate rinsing, twice a week for 30 days during orthodontic treatment, is effective in reducing the presence and levels of A actinomycetemcomitans on metallic brackets.