Abstract:

Objective:This study was designed to find out the changes in microflora on the stress-bearing areas after insertion of remov- able partial dentures, and in turn to explore the difference between such changes caused by metal bases and acrylic resin bases re- spectively.Methods:Sixteen patients who were ready to accept removable partial dentures were selected and divided into two groups. Eight patients used metal baseswhile the other eight patients used acrylic resin bases. Then at the following three points: before dentureswere inserted, one month afterwearing and three months afterwearing, the total cultivable flora were counted and the proportions of bacteria detected on the stress-bearing areaswere calculated.Results:No matterwhat type of baseswas select- ed, the wearing of removable partial denture enhanced the accumulation of microflora on stress-bearing areas. The percentages of Candida albicansandLactobacillidetected on stress-bearing areas also increased significantly (P<0.05). When such changes were compared, the authorsfound thatthe incrementofCandida albicanscaused by acrylic resin baseswas higherthan that caused by metal bases (P<0.05).Conclusion:The wearing of removable partial dentures forms new retention areas between the bases and the stress-bearing areas, as a result enhances the deposit of microbe and facilitate the growth ofCandida albicansandLacto- bacilli. Compared with increment ofCandida albicanscaused by metal bases, the increment relating to acrylic resin bases ismore evident.

Key words: removable partial denture, acrylic resin base, metal base, microflora