Evaluating the growth of candida albicans on removable complete dentures bases manufactured using CAD/CAM designed metal (Co-Cr casted from milled wax patterns) and injection molded resin

Abstract

Acrylic resin processed by compression molded technique had been used to manufacture the removable complete dentures bases for many years. However there are many disadvantages connected to the use of this material with the ordinary compression molding as a denture base, the reason that made the researches try to find a better alternatives whether by changing the processing technique: like in the case of using acrylic resins processed by injection molded technique which proved to be a better choice in many aspects, on the other hand some researchers preferred to use another material so they used metal bases as replacement for the ordinary acrylic denture base. There are many ways to make patterns for metal bases casting in partial and complete dentures. Recently many researchers and practitioners used CAD-CAM technologies to make patterns for metal casting and facilitate the work, and save time. This study compares the candida albicans colony formation on the two materials mentioned above as an advantage to the material studied.Purpose: The purpose of this study is to compare the growth of candida albicans on removable complete dentures bases manufactured using CAD/CAM designed metal (Co-Cr casted from milled wax patterns) and injection molded acrylic resin. Materials and Methods: Split-palate maxillary complete dentures were fabricated for 10 edentulous patients. one-half of the palate was made in acrylic resin and the other half in Co-Cr metal palate that was casted from CAD-CAM milled patterns for each patient in this study. specimens were collected at 1, 3, and 5 months using a modified imprint culture method. Speciation of Candida albicans was performed using a chromogenic culture medium. Two-sample t-test was employed to determine effects and significant interactions between the acrylic and the metal groups. Results: Significant differences were observed in the candida albicans colony counts between both materials during the first, the third, and the fifth month. The Colony forming unit(CFU)/cm2 means were significantly less on the Co-Cr casted metal denture bases than CFU/cm2 means on the injection molded acrylic resin. Conclusions: The metal base proved to be effective in decreasing the candida albicans growth typically present in complete dentures. Colony counts of Candida albicans were higher in the injection molded acrylic resin part of denture bases of the patients in this study.