Evaluation of donor skin disinfection methods.

BACKGROUND: Because most bacteria isolated from contaminated platelet concentrates are thought to originate from the donor's skin, the efficacy of four methods of skin disinfection was compared. STUDY DESIGN AND METHODS: Contact plates were used for antecubital skin cultures after they were demonstrated to be easier to use and at least as sensitive as a swab system. One antecubital fossa of each subject was disinfected by a standard method, the use of a povidone-iodine swabstick containing 0.75-percent available iodine followed by the use of a povidone-iodine swabstick containing 1-percent available iodine. The other arm was disinfected with either a 70-percent isopropyl alcohol scrub followed by an ampoule of 2-percent iodine tincture (Group 1; n = 126); a green-soap sponge followed by a 70-percent isopropyl alcohol swab, used for donors who are allergic to iodine (Group 2; n = 30); or a 0.5-percent chlorhexidine gluconate and 70-percent isopropyl alcohol sponge followed by an ampoule of 0.5-percent chlorhexidine gluconate and 70-percent isopropyl alcohol (Group 3; n = 40). Contact plate cultures were done before and after disinfection, and colonies counted after a 48-hour 37 degrees C incubation period. RESULTS: Similar numbers of bacteria grew from both antecubital fossae of the same subject before disinfection (p = 0.71). Compared to the standard povidoneiodine method, isopropyl alcohol and tincture of iodine resulted in significantly less bacterial growth (p < 0.001), the green soap and isopropyl alcohol method resulted in significantly more bacterial growth (p < 0.001), and the chlorhexidine gluconate and isopropyl alcohol method resulted in similar amounts of bacterial growth (p > 0.3). CONCLUSION: Isopropyl alcohol scrub followed by iodine tincture is more efficacious than povidone-iodine as measured by contact plate cultures. For donors who are allergic to iodine, chlorhexidine gluconate and isopropyl alcohol is more efficacious than green soap and isopropyl alcohol.

The results after 20 months of a study testing the efficacy of a weekly fluoride mouthrinsing program.

The purpose of this study was to determine the efficacy of weekly mouthrinsing with a 0.2 percent NaF solution in first-grade children living in a non-fluoridated community. Children in the control group were also participants in a randomized clinical trial to evaluate the efficacy of semiannual fluoride varnish treatments. Children allocated to the mouthrinse group attended school at three of the 17 area schools where the varnish study was occurring. Random allocation of children into the treatment group was considered impractical because of potential problems of teacher cooperation and compliance. The same two standardized examiners examined all participants, and were blind to group assignment for all children. After two academic years, or approximately 72 weeks of rinsing, 178 and 247 children remained in the treatment and control groups, respectively. The control group experienced a mean caries rate of 2.02 surfaces over 20 months, while the treatment group demonstrated an increment of only 1.33 surfaces, representing a savings of about 0.34 surfaces per year or a reduction in DMFS of 34.2 percent. Surface-specific incremental reductions after 20 months were 0.35, 0.19, and 0.14 for the occlusal, buccal, and lingual surfaces, respectively. The proximal increment was too small to draw any meaningful conclusions. In the primary dentition, the treatment and control dfs increments were 0.74 and 1.74, respectively. This reduction represents a savings of one-half surface increment per year, or a reduction of 57.5 percent.