title: Cytotoxicity and biocompatibility of Zirconia (Y-TZP) posts with various dental cements.
abstract: OBJECTIVE
  Endodontically treated teeth with insufficient tooth structure are often restored with esthetic restorations. This study evaluated the cytotoxicity and biological effects of yttria partially stabilized zirconia (Y-TZP) blocks in combination with several dental cements.
  
  
  METHODS
  Pairs of zirconia cylinders with medium alone or cemented with three types of dental cement including RelyX U200 (3M ESPE), FujiCEM 2 (GC), and Panavia F 2.0 (Kuraray) were incubated in medium for 14 days. The cytotoxicity of each supernatant was determined using 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays on L929 fibroblasts and MC3T3-E1 osteoblasts. The levels of interleukin-6 (IL-6) mRNA were evaluated by reverse transcription polymerase chain reaction (RT-PCR), and IL-6 protein was evaluated by enzyme-linked immunosorbent assays (ELISA). The data were analyzed using one-way ANOVA and Tukey post-hoc tests. A p < 0.05 was considered statistically significant.
  
  
  RESULTS
  The MTT assays showed that MC3T3-E1 osteoblasts were more susceptible to dental cements than L929 fibroblasts. The resin based dental cements increased IL-6 expression in L929 cells, but reduced IL-6 expression in MC3T3-E1 cells.
  
  
  CONCLUSIONS
  Zirconia alone or blocks cemented with dental cement showed acceptable biocompatibilities. The results showed resin-modified glass-ionomer based cement less produced inflammatory cytokines than other self-adhesive resin-based cements. Furthermore, osteoblasts were more susceptible than fibroblasts to the biological effects of dental cement.
authors: Department of Conservative Dentistry, Asan Medical Center, Ulsan University, Seoul, Korea.
authors: Hyeongsoon
authors: H
authors: Shin
authors: Department of Conservative Dentistry, Asan Medical Center, Ulsan University, Seoul, Korea.
authors: Hyunjung
authors: H
authors: Ko
authors: Department of Conservative Dentistry, Asan Medical Center, Ulsan University, Seoul, Korea.
authors: Miri
authors: M
authors: Kim
keywords: Biocompatibility; Cytotoxicity; Resin cement; Zirconia