理想之乳牙根管充填材料須具備有可吸收性與生物相容性。過去研究報告指出經過乳牙根管治療後之患者其恆牙萌出會受到影響。本文研究目的乃探討目前常用之根管充填材料( 氫氧化鈣與氧化鋅丁香油酚) 對人類骨細胞之生物相容性。研究方法: 以MTT粒線體呈色反應比較其細胞存活率，以DNA有無裂解分析細胞可能產生毒性之機轉。結果顯示： Vitapex, Canals 新鮮製備溶液與經過24小時組對細胞之存活率呈劑量相關性(p<0.05) 。而Tubil seal則只於經過24小時組對細胞之存活率呈劑量相關性(p<0.05) 。DNA裂解研究發現不論是新鮮製備溶液與經過24小時組對細胞均有DNA裂解。作者認為乳牙根管充填材料會對人類骨細胞造成細胞自殺(Apoptosis)現象。建議使用此材料時應盡量避免穿出根尖孔，以減少對恒牙之影響。
An ideal temporary root canal sealer for primary teeth should be resorbable and biocompatible. It has been reported that some left over root canal sealers can cause eruption of the permanent tooth. The purpose of the present study is to evaluate the biologic effect of the root canal sealers of primary tooth. The survival rates of calcium hydroxide based and zinc oxide eugenol root canal sealer were tested in cultured U2OS cells by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay. DNA fragmentation assay was used to evaluate the toxic mechanism. The result showed that the survival rate of Vitapex fresh extract and 24-hour extract were found to have dose-dependent decreases (p<0.05). The survival rate of Tubli seal fresh extract was found to decrease dose-dependently (p<0.05). The survival rate of Canals fresh and 24 hour extracts were found to decrease dose-dependently (p<0.05). DNA fragmentation showed that fresh extract and 24 hour extract group of the sealers showed had DNA cleavage that appeared as ladder patterns on electrophoresis gel. The primary tooth root canal sealers can cause U2OS cell toxicity and induce apoptosis. To prevent the alteration or interference of the permanent tooth eruption, one should avoid overuse of sealer or leaving too much sealer on the apical tissue.
