A pilot study of the effects of a vacuum sealing barrier method for photostimulable phosphor plates regarding plate damage and prevention of microbiologic cross-contamination.

OBJECTIVE: The aim of this study was to evaluate the effectiveness of a new sealing method for preventing cross-contamination of photostimulable phosphor (PSP) plates. STUDY DESIGN: Twelve new PSP plates were divided into 3 groups (PSP-a, PSP-b, and PSP- c) and placed in 3 different barriers (2 different brands of envelopes and a vacuum sealing method). All plates were exposed to X-rays with an aluminum step wedge, and the images were evaluated for the presence of any artifacts. After radiography, the PSP plates were removed from the barriers. The barriers and the PSP plates were disinfected and culture performed to assess any microorganism burden. Subsequently, the PSP plates were coated again with all barriers. The barriers were then contaminated and microbiologic specimens were collected. Subsequently, the barriers were wiped with alcohol. The PSP plates were removed, and microbiologic specimens were obtained. RESULTS: No artifacts were recorded on the radiographic images on the sensors in any group. Microorganisms were detected on the PSP plates placed in envelopes. No colonization of microorganisms was detected on the vacuum sealed PSP plates. CONCLUSIONS: The new vacuum-sealing method may be useful in preventing cross-contamination of PSP plates during radiographic procedures.

An evaluation of microbiologic contamination on phosphor plates in a dental school.

OBJECTIVE: The objective of this study was to determine if phosphor plates used in predoctoral clinics are microbiologically contaminated and to identify the source of contamination. STUDY DESIGN: Forty-five of 300 phosphor plates (15%) were randomly selected for examination. The plates were pressed into individual blood agar plates, were incubated using standard techniques at 37 degrees C, and were monitored for 72 hours. The number, size, distribution, and variety of resulting colonies were noted. A representative of each type of colony was selected to be Gram stained using the standard technique. RESULTS: Of the plates, 42.2% were uncontaminated, 57.8% yielded bacterial colonies, and 15.6% of those colonies demonstrated hemolytic growth. The hemolytic growth included combined alpha and beta hemolysis and beta only hemolysis. Six colonies were gram-positive rods and 7 were gram-positive cocci. CONCLUSION: Meticulous infection-control techniques are inevitable and continuous reinforcement and training for staff and students are mandatory. Periodic gas sterilization of phosphor plates may be necessary.