Surface disinfection of saliva-contaminated dental X-ray film packets

A study was undertaken to determine the most effective method for the surface disinfection of saliva-contaminated dental X-ray film packets. Size 2 Kodak Poly-Soft film packets were placed in the oral cavities of patients and "sham" irradiated. After removal from the oral cavity, some of these packets were left untreated before being placed in transfer vials containing transport medium. Other packets were handled in one of three different ways before being placed in the transfer vials: 1) wiped with a piece of sterile tissue paper to remove visible saliva; 2) wiped once with a sterile piece of gauze soaked with disinfectant and then immediately wiped dry with a piece of tissue paper ("one-wipe" surface-disinfection technique); or, 3) wiped twice with a sterile piece of gauze soaked with disinfectant and allowed to air dry ("two-wipe" surface-disinfection technique). The transport medium was serially diluted and microbiological processing completed to obtain bacterial counts corresponding to the levels of bacterial contamination of the film packet surfaces. The two-wipe surface-disinfection method effectively eliminated bacterial contamination of the film packets, with all of the disinfectants tested being equally effective. The one-wipe technique, using disinfectant, appeared to be slightly less effective. Mere physical removal of the saliva from the film packet, without the use of disinfectant, was the least effective method.