Forty-six patients (20 male and 26 female, age 45-76) with temporary dental prosthesis were followed-up both clinically and microbiologically. The results of quantitive and qualitive assessment proved biofilm formed on acrylic resin to be potentially more aggressive because of high incidence and significant number of virulent germs as well as yeast-like Candida fungal. Laboratory polished polyurethane samples showed much lower colonization by virulent germs and Candida fungal. After biofilm stabilization PCR revealed twice-fold less incidence of virulent germs on polyurethane when compared to other tested materials.