A Novel Approach to Screen Dental Material Biocompatibility

Objectives: To use real time PCR to validate the gene expression data from Affymetrix gene expression profiling in dental materials treated human gingival epithelial cells.
Methods: Human gingival epithelial cells (S-G) were cultured as previously reported. The cells were treated for 24 hours with dental materials Rely-X Unicem-2 (3M ESPE) or Ketac™ Fil Plus Aplicap™ Glass Ionomer Restorative (3M ESPE). The untreated cells were used as controls. Total RNA was isolated and purified. High quality RNAs were used for microarray assay (Affymetrix clarioms) and real time PCR.
Results: Compared to controls, real time PCR data showed that CXCL8 were upregulated by 16.4 folds in Ketac-treated cells and HOMX1 were upregulated by 12.9 folds in RelyX-treated cells. The results are consistent with data from microarray analysis.
Conclusions: Real time PCR results validated some gene expression data from Affymetrix microarray analysis. CXCL8 gene encodes Interleukin 8 (IL-8), which is a major cytokine involved in the recruitment of neutrophils to the site of damage or infection. The upregulation of CXCL8 gene suggests that these dental materials might elicit inflammatory responses in clinical applications.