Although improved oral hygiene and hygienic prosthetic restorations are prerequisites for a healthy state of periodontal tissues around dental restorations by impeding occurence of gingivitis and periodontitis, the surface characteristics of dental restorative materials can also present important factors. The aim of this study was to evaluate the adhesion of Actinobacillus actinomycetemcomitans (A.a) and Streptococus mutans (S.mutans), which are accepted to be the infectious agents, to current prosthetic restorative materials. The bacterial suspensions of A.a (ATCC 29523) and S.mutans (Refik Saydam culture collection 676) were prepared and the initial bacterial counts were determined by using a nephelometric method (Uro- Quick, Italy). Cr-Ni, In-Ceram, Empress 2 translucent, Ivoclar, Empress 2 dentin, Alphadur and Empress II ingot were used as prosthetic restorative materials to evaluate bacterial adhesion. These materials were placed in 24 well plates and sterile saliva, and bacteria were added. Specific broths for each strain were, then, transferred in well plates and incubated for the adhesion. The bacteria adhered to the surface of restorative materials were detached by sonification procedure and measured by nephelometric method. The viability of bacteria were evaluated in specific media. The procedure was repeated for three times and the mean of measurements were calculated. The measurement of viable bacteria count by culture method indicated that A.a adhered in small amounts on Cr-Ni surface and in higher amounts on In-Ceram and Empress 2 ingot surfaces. The highest S.mutans adherence was found on Empress 2 ingot, although S.mutans adhered to a lesser extent on all specimens when compared to A.a. Nephelometric measurement demonstrated that A.a adhered in small amounts on Alphadur and in higher amounts on Cr-Ni surface. The highest S.mutans adherence was measured on Empress 2 translucent, and the lowest on In-Ceram, Empress 2 dentin and Alphadur surfaces. The use of Cr-Ni can be suggested on teeth distant to esthetic zone or underneath ceramic materials due to less bacterial adhesion on this material when all prosthetic restorative materials were evaluated.

Keywords: Bacterial adhesion, Empress, In-Ceram, porcelain, ceramic