Zhao Dan, Shen Ya, Peng Bin, Haapasalo Markus
State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.
Division of Endodontics, Department of Oral Biological and Medical Sciences, Faculty of Dentistry; Department of Materials Engineering, The University of British Columbia, Vancouver, Canada.
J Endod. 2014 Nov;40(11):1860-4. doi: 10.1016/j.joen.2014.06.023. Epub 2014 Sep 6.
The aim of this study was to describe the canal shaping properties of ProTaper Next (PTN; Dentsply Maillefer, Ballaigues, Switzerland), ProTaper Universal (PTU; Dentsply Tulsa Dental Specialties, Johnson City, TN), and WaveOne (Dentsply Maillefer) nickel-titanium instruments in mandibular first molars by using micro-computed tomographic (micro-CT) scanning.
A total of 36 maxillary first molars with 2 separate mesial canals and 1 distal canal were selected and scanned preoperatively and postoperatively by using micro-CT scanning with a voxel size of 30 μm. Canals were prepared with PTU, PTN, and WaveOne systems under hypochlorite irrigation. The volume of the untreated canal; the volume of dentin removed after preparation; the amount of the uninstrumented area; and the transportation to the coronal, middle, and apical thirds of canals were measured. The preparation time and instrument failure were also recorded.
Instrumentation of canals increased their volume and surface area. The distal canals had a significantly higher proportion of unprepared surfaces than mesial canals (P < .05). The PTN system produced less transportation than the WaveOne and PTU systems in the apical third of the mesial canals (P < .05). There was no significant difference on apical transportation in distal canals among the 3 instrument systems. Instrumentation with WaveOne was significantly faster than with the other 2 instruments (P < .05).
The PTN, PTU, and WaveOne instruments shaped root canals in mandibular first molars in vitro without significant shaping errors. The curved canals prepared using PTN had less apical transportation than the canals prepared using WaveOne and PTU.
本研究的目的是通过使用显微计算机断层扫描（micro-CT）来描述ProTaper Next（PTN；登士柏美福，瑞士巴拉格）、ProTaper通用型（PTU；登士柏塔尔萨牙科专业产品公司，田纳西州约翰逊城）和WaveOne（登士柏美福）镍钛器械在下颌第一磨牙中的根管预备特性。
总共选择了36颗具有2个独立近中根管和1个远中根管的上颌第一磨牙，术前和术后使用体素尺寸为30μm的micro-CT进行扫描。在次氯酸钠冲洗下，用PTU、PTN和WaveOne系统预备根管。测量未处理根管的体积；预备后去除的牙本质体积；未器械操作区域的量；以及根管冠部、中部和根尖三分之一处的移位情况。还记录了预备时间和器械折断情况。
根管预备增加了其体积和表面积。远中根管未预备表面的比例显著高于近中根管（P <.05）。在近中根管的根尖三分之一处，PTN系统产生的移位比WaveOne和PTU系统少（P <.05）。3种器械系统在远中根管的根尖移位方面无显著差异。使用WaveOne进行预备明显比使用其他2种器械快（P <.05）。
PTN、PTU和WaveOne器械在体外预备下颌第一磨牙的根管时，无明显的预备误差。使用PTN预备的弯曲根管比使用WaveOne和PTU预备的根管根尖移位少。
