Yahata Yoshio, Masuda Yoshiko, Komabayashi Takashi
Department of Endodontics, School of Dentistry, West Virginia University, Morgantown, West Virginia, USA.
Division of Endodontology, Department of Conservative Dentistry, School of Dentistry, Showa University, Tokyo, Japan.
Aust Endod J. 2017 Dec;43(3):123-128. doi: 10.1111/aej.12190. Epub 2017 Jan 13.
The aim of this study was to compare the apical centring ability of incisal-shifted access (ISA) with that of traditional lingual access (TLA). Fifteen three-dimensional printed resin models were prepared from the computed tomography data for a human maxillary central incisor and divided into ISA (n = 7), TLA (n = 7) and control (n = 1) groups. After access preparation, these models were shaped to the working length using K-files up to #40, followed by step-back procedures. An apical portion of the model was removed at 0.5 mm coronal to the working length. Microscopic images of each cutting surface were taken to measure the preparation area and the distance of transportation. TLA created a larger preparation area than ISA (P < 0.05). The distance of transportation (mean ± standard deviation) was 0.4 ± 0.1 mm for ISA and 0.7 ± 0.1 mm for TLA (P < 0.05). Access cavity preparation has a significant effect on apical centring ability. ISA is beneficial to maintaining apical configuration.
本研究的目的是比较切端移位入路（ISA）和传统舌侧入路（TLA）的根尖对中能力。根据一名人类上颌中切牙的计算机断层扫描数据制备了15个三维打印树脂模型，并将其分为ISA组（n = 7）、TLA组（n = 7）和对照组（n = 1）。开髓预备后，使用K锉将这些模型修整至工作长度，直至#40，随后进行逐步后退操作。在距工作长度冠方0.5 mm处切除模型的根尖部分。拍摄每个切割面的微观图像以测量预备面积和偏移距离。TLA产生的预备面积比ISA大（P < 0.05）。ISA的偏移距离（均值±标准差）为0.4±0.1 mm，TLA为0.7±0.1 mm（P < 0.05）。开髓洞形预备对根尖对中能力有显著影响。ISA有利于保持根尖形态。
