Effects of dental radiation on the expression of apoptotic-related gene in primary human bone cells

Abstract

Exposure to 1 milligray ionizing radiation could induce DNA lesions probably leading to cell death through apoptotic process. Thus, performing dental radiography in a milligray range might be dangerous to human bone cells. The purpose of this study was to investigate the effects of dental radiation on the expression of apoptotic-related gene in primary human bone cells. Human bone cells were grown in 15% DMEM and irradiated with 0, 1, 2 doses of a periapical radiograph. The cytotoxicity of irradiation was investigated by MTT assay after 24 hours. The level of apoptotic-related gene expression (Bcl-2, Bax, Bad, Bcl-XL, Caspase-3) was analyzed by RT-PCR assay, four hours post irradiation No cytotoxicity was observed at 24 hours after dental irradiation. Interestingly, most of the results demonstrated a decrease of apoptotic-related gene expression at 4 hours after dental irradiation. Only Bax and Caspase-3 were significantly decreased compared to the control. In conclusion, dental radiation affects apoptotic-related gene expression. Therefore, prescribing dental radiograph should be highly selective and the principle of ALARA (As Low As Reasonably Achievable) should be followed.