Fujisawa S, Atsumi T, Satoh K, Sakagami H
Department of Oral Diagnosis, Meikai University, School of Dentistry, Sakado, Saitama, Japan.
J Dent Res. 2003 Jan;82(1):43-7. doi: 10.1177/154405910308200110.
The liquid of 2-ethoxybenzoic acid cements is composed of 2-ethoxybenzoic acid and eugenol (4-allyl-2-methoxyphenol). Recently, eugenol was reported to produce radicals at a higher pH, which consequently directly damages cells. We examined here whether eugenol radicals are generated from the mixture of eugenol/calcium hydroxide, and also whether 2-ethoxybenzoic acid or acetylsalicylic acid scavenges radicals, using electron spin resonance spectroscopy. Radicals were generated from the mixture of eugenol/calcium hydroxide in 50% dimethylsulfoxide solution. The radical intensity of eugenol in 50% dimethylsulfoxide with 0.1 M sodium bicarbonate buffer (pH 9.5) was dose-dependently reduced by 2-ethoxybenzoic acid, whereas it was enhanced by acetylsalicylic acid. Next, we investigated the cytotoxic effect of eugenol on 2-ethoxybenzoic acid, acetylsalicylic acid, or calcium hydroxide on human pulp fibroblasts or a human submandibular gland cancer cell line. The cytotoxicity of EBA was decreased, whereas that of acetylsalicylic acid was increased by eugenol. In contrast, that of calcium hydroxide was not affected by eugenol. Human pulp fibroblast but not human submandibular gland cells showed a high resistance against calcium hydroxide. The generation of eugenol radicals in the liquid of 2-ethoxybenzoic acid cements caused by oxidation may be suppressed by 2-ethoxybenzoic acid.
2-乙氧基苯甲酸粘固剂的液体由2-乙氧基苯甲酸和丁香酚（4-烯丙基-2-甲氧基苯酚）组成。最近有报道称，丁香酚在较高pH值下会产生自由基，从而直接损害细胞。我们在此使用电子自旋共振光谱法研究了丁香酚/氢氧化钙混合物中是否会产生丁香酚自由基，以及2-乙氧基苯甲酸或乙酰水杨酸是否能清除自由基。在50%二甲基亚砜溶液中，丁香酚/氢氧化钙混合物会产生自由基。在含有0.1 M碳酸氢钠缓冲液（pH 9.5）的50%二甲基亚砜中，丁香酚的自由基强度会因2-乙氧基苯甲酸而呈剂量依赖性降低，而因乙酰水杨酸而增强。接下来，我们研究了丁香酚对2-乙氧基苯甲酸、乙酰水杨酸或氢氧化钙对人牙髓成纤维细胞或人下颌下腺癌细胞系的细胞毒性作用。丁香酚降低了EBA的细胞毒性，而增加了乙酰水杨酸的细胞毒性。相比之下，氢氧化钙的细胞毒性不受丁香酚影响。人牙髓成纤维细胞而非人下颌下腺细胞对氢氧化钙表现出高度抗性。2-乙氧基苯甲酸粘固剂液体中由氧化引起的丁香酚自由基的产生可能会被2-乙氧基苯甲酸抑制。
