Healthcare workers and medical students are at risk of exposure to blood-borne viruses such as HBV, HCV HIV, etc. Here we report the results of a survey of the frequency and causes of cutaneous blood exposure accidents (CBEA) among medical students. Anonymous questionnaires were randomly distributed to 200 interns in their second year of internship in hospitals affiliated to Tehran University of Medical Sciences. A definite exposure was defined as injury by a sharp object causing obvious bleeding, whereas a possible exposure was defined as subtle or superficial injury due to contact with a contaminated instrument or needle but without bleeding, or contamination of an existing wound with blood or other body fluids. One hundred eighty-four subjects (92% of the original sample) responded to the questionnaire. We recorded 121 definite exposures and 259 possible exposures over a mean time interval of 14 months. Needles were the most common objects (41% of exposure episodes) causing CBEAs, while phlebotomy and suturing were the hospital procedures that accounted for the highest percentage of exposure episodes (30 and 28 percent, respectively). Only a minority of students regularly observed basic safety measures (wearing gloves, not recapping used needles and proper disposal of sharp objects). Considering the high incidence of blood exposure in medical interns at Tehran University of Medical Sciences and the ensuing risk of blood-borne infections, the subjects are likely to develop such infections during their internship period.

Objective: To evaluate whether biomarkers of inflammation and periodontal remodeling are differentially expressed in the gingival crevicular fluid (GCF) of patients wearing different types of orthodontic retainers. Materials and Methods: Thirty-one adult subjects (17 men and 14 women with an age range of 20 to 35 years) were allocated to three different groups. Group 1 consisted of 10 patients wearing fixed retainers, group 2 included 11 patients using lower removable retainers, and group 3 comprised 10 patients without retainers (control). Periodontal health assessment and GCF collection were carried out at two sites per subject: the lingual side of a central lower incisor and the lingual side of a lower second premolar. Aliquots from diluted GCF were screened for the presence of biomarkers using a microarray technique. Results: Group 1 patients exhibited a higher percentage of sites with visible plaque in the incisor region than the other groups (P 5 .03); no differences were noted in gingival bleeding and probing depths. The median concentrations (pg/mL) of interferon-gamma and interleukin-10 were significantly higher in the premolar sites of patients in group 2 (P 5 .01 and P 5 .04, respectively), whereas the concentration of matrix metalloproteinase-9 was significantly higher at the incisors of patients wearing fixed retainers (P 5 .02). A significant difference between the two sites was seen only in group 2. Conclusions: The presence of different orthodontic retainers may promote specific alterations in the GCF composition. With retention periods potentially becoming longer, this finding may be of clinical significance. (Angle Orthod. 2011;81:1083-1089