Skin Sensitization Evaluation of Dental Calcium Hydroxide Medication with Local Lymph Node Assay Using Bromodeoxyuridine Immunohistochemistry in Balb/c Mice

Abstract

Medical devices including dental materials should pass biocompatibility test for the premarket approval. Depending on the categorization of device, required biocompatibility tests are different. During endodontic treatment, calcium hydroxide medication has been used for a long time. However, the clinical cases involving in clinical cases of adverse effects of calcium hydroxide paste were reported in some papers. In addition, due to the alkaline pH, the biocompatibility of calcium hydroxide paste is still questionable for practices. Here, we developed novel root canal treatment calcium hydroxide medication containing silicon-substituted hydroxyl apatite (Si-HA) which has been used as bone graft material. In this study, we conducted hypersensitivity test with LLNA: BrdUELISA method for the evaluation of sensitization potential of allergen. All test methods were according to OECD guideline and ISO 10993 series and results were statistically analysed with SPSS. There were no significant differences among test groups, vehicles and negative control in body weight, ear thickness and ear weight. Only positive control showed statistically significant difference in stimulation index (SI). In conclusion, we assumed that newly developed calcium hydroxide medication has no sensitization material. We also confirmed that LLNA with BrdU using ELISA is appropriate method to identify sensitizing chemicals in dental materials