Al-Dewani N, Hayes S J, Dummer P M
Department of Adult Dental Health, University of Wales College of Medicine, Cardiff, UK.
J Endod. 2000 Dec;26(12):733-8. doi: 10.1097/00004770-200012000-00018.
The aim of this study was to evaluate and compare the radiographic quality and sealability of root fillings in extracted human teeth using lateral condensation of gutta-percha or low-temperature thermoplasticized gutta-percha (Ultrafil). One hundred freshly extracted human, mature single-rooted teeth were divided into four identical groups of 25 teeth on the basis of root canal shape. The root canals of two groups were prepared in such a way to produce a relatively parallel shape with little or no flare toward the coronal orifice. The root canals of the other two groups were prepared in such a way as to produce a canal shape that was deliberately more flared to ensure that they were wider at the orifice than at the end point of the preparation. All root canals were flushed with 17% EDTA solution and 2.5% NaOCl to remove the dentinal smear layer. The canals of one flared group and one parallel group were obturated using cold lateral condensation, and the canals of the other two groups were obturated using low-temperature thermoplasticized gutta-percha. The sealability of each technique was assessed by a dye penetration method. The radiographic quality of obturation was determined for each canal using a 4-point scale. Canals filled with thermoplasticized gutta-percha had significantly less apical dye penetration than those obturated by lateral condensation (p < 0.001). Lateral condensation achieved significantly better scores for radiographic quality than thermoplasticized gutta-percha from both the buccolingual (p < 0.005) and mesiodistal views (p < 0.001). Low-temperature thermoplasticized gutta-percha root fillings were associated with significantly more apical extrusion of sealer (p < 0.001) and gutta-percha (p < 0.005). Under laboratory conditions the low-temperature thermoplasticized gutta-percha had better sealability but poorer radiographic quality than lateral condensation.
本研究的目的是评估和比较使用牙胶侧向加压法或低温热塑牙胶（Ultrafil）对拔除的人牙进行根管充填后的影像学质量和封闭性。100颗新鲜拔除的人成熟单根牙根据根管形态分为四组，每组25颗牙。两组根管的预备方式是使其呈相对平行的形态，向冠方开口处几乎没有或仅有轻微的喇叭口状。另外两组根管的预备方式是使其呈特意更宽大的形态，以确保其开口处比预备终点处更宽。所有根管均用17%乙二胺四乙酸（EDTA）溶液和2.5%次氯酸钠冲洗，以去除牙本质玷污层。一组宽大根管组和一组平行根管组的根管采用冷侧向加压法进行充填，另外两组根管采用低温热塑牙胶进行充填。每种技术的封闭性通过染料渗透法进行评估。使用4分制对每个根管的充填影像学质量进行判定。与侧向加压法充填的根管相比，热塑牙胶充填的根管根尖部染料渗透明显更少（p<0.001）。从颊舌向（p<0.005）和近远中向（p<0.001）观察，侧向加压法在影像学质量方面的得分明显高于热塑牙胶。低温热塑牙胶根管充填与根管封闭剂（p<0.001）和牙胶（p<0.005）的根尖部挤出明显更多有关。在实验室条件下，低温热塑牙胶的封闭性优于侧向加压法，但影像学质量较差。
