Evaluation of cleansing methods for previously worn prostheses.

STATEMENT OF PROBLEM: Although there are many product claims that address the issue of denture sanitization, controlled scientific studies on previously worn dentures have not been performed. PURPOSE: The purpose of this study was to evaluate procedures directed at sanitizing previously worn contaminated dentures from two regions of the United States. MATERIALS AND METHODS: This study examined 51 previously worn dentures from two regions. An established method of denture retrieval, sectioning, and culturing was used, including isolation of anaerobes. Evaluation of microbial contamination posttreatment was used to determine the effects of soaking dentures in Polident (US and European formulations) for varying periods of times/temperatures, microwaving dentures with varying temperatures, sonicating dentures, and immersing the dentures while using a vacuum. A combination of analysis of variance (ANOVA) and general linear model (GLM) of the SPSS was used to analyze the data with P < .05 being considered statistically significant when using a two-tailed test. RESULTS: While all Polident treatments were found to significantly reduce microorganism loads in dentures, extended soaking (8 hours) and 65 degrees C (5 minutes) were the most effective. Microwaving was slightly more effective than either sonication or vacuum. Regardless the treatment, dentures underwent sanitization rather than sterilization. CONCLUSIONS: Denture-borne microorganisms can be significantly reduced by using a Polident solution for 8 hours at room temperature or for 5 minutes at 65 degrees C. Microwaving, sonication, and use of a vacuum were less effective. ClLINICAL IMPLICATIONS The importance of daily use of Polident solution for 8 hours or for 5 minutes at 65 degrees C to sanitize worn prostheses must be stressed.

Evaluation of microbial flora found in previously worn prostheses from the Northeast and Southwest regions of the United States.

STATEMENT OF PROBLEM: Denture-induced stomatitis is a recognized clinical challenge. The responsible microorganisms have not been delineated and may differ among regions of the United States. PURPOSE: The purpose of this study was to identify the microorganisms found in dentures from 2 geographic regions. MATERIAL AND METHODS: Previously worn dentures from 51 available subjects living in the Southwest (41) and Northeast (10) were aseptically retrieved in sterile plastic bags. A posterior piece of the mandibular denture was removed and sampled on appropriate media under anaerobic conditions. The remaining denture material was divided into 7 equal pieces. Each piece was touched to appropriate aerobic media and incubated at 37 degrees C. Bacteria and yeasts were identified using standard clinical laboratory procedures. Data were analyzed by using descriptive statistics. Denture fragments were further analyzed by scanning electron microscopy (SEM). RESULTS: A total of 916 isolates were carried to final speciation. Of these, 711 were aerobic bacteria, 67 were anaerobic bacteria, 125 were yeasts, and 13 were amoebae. Microorganisms were found on the denture surfaces and interstices (denture pores). Most subjects wore their dentures for extended periods without sanitization. SEM analyses confirmed substantial porosity of the denture material with microbial penetration and biofilm formation within the pores. CONCLUSIONS: A wide range of potentially pathogenic microorganisms was found in dentures. There were also regional differences in the microbial flora.