In-vivo and in-vitro comparison of an amorph calcium phosphate containing resin restorative material with traditional restorative materials

Secondary caries is one of the most common problems in restorative dentistry. Antimicrobial or remineralizing agents are added into the restorative materials to prevent secondary caries. Amorphous calcium phosphate (ACP) is one such agent added to the composite resins. In the in vivo part of the present study, immunological, biochemical and microbiological reactions to ACP-containing nanocomposite and traditional composite were evaluated in gingival crevicular fluid (GCF) and dental plaque samples. Moreover, clinical success of the restorative materials were recorded according to the FDI criteria. In the in vitro part of the study, antibacterial activity of different restorative materials were investigated in the medium for L. acidophilus and S. mutans and the surface properties of the restorative materials were evaluated with a scanning electron microscope (SEM). Fourteen pediatric patients were included in the present study with split mouth design; 18 teeth were restored with test material and 18 teeth were restored with control material. GCF and dental plaque samples were collected at baseline before the treatment, and then on days 1, 7, 14 and 30 after the treatment. Unstimulated whole saliva samples were obtained at baseline, 1 and 6 months after restoration. GCF and saliva samples were assayed for IL-17, OPG and RANKL levels by ELISA, and the plaque samples were analyzed by real-time PCR. Cytokine levels in saliva samples decreased significantly at 6th month compared to baseline and 1st month. The baseline proinflammatory cytokine levels in GCF samples around the carious teeth were higher than those around the healthy teeth. RANKL, OPG levels and RANKL/OPG ratio were also determined in the GCF samples. RANKL level and RANK/OPG ratio were higher in the caries group than the healthy control (p<0,05). There were no statistically significant differences between the study groups in the microbiological data obtained in the plaque samples (p>0,05). In clinical evaluations according to the FDI criteria, the test and control materials showed changes in the marginal adaptation and aesthetic features, but there was no statistically significant difference between the two materials tested (p>0,05). Agar diffusion test was performed to evaluate the antibacterial activity of the restorative materials. Chlorhexidine cavity disinfectant showed the most extensive inhibition zones and the test material showed antimicrobial activity against S. mutans with varnished as well as unvarnished forms compared to the conventional composites. Conventional composite showed no antimicrobial activity. The data obtained with SEM indicated that there were many surface irregularities on the control material, which caused an increase in plaque accumulation. However, the failure of complete simulation of the oral biofilm, we could not show dense microbial deposits on the restorative material surfaces.