Nagas Emre, Cehreli Zafer C, Uyanik Ozgur, Vallittu Pekka K, Lassila Lippo V J
Department of Endodontics, Faculty of Dentistry, Hacettepe University, Ankara, Turkey.
Department of Pediatric Dentistry, Faculty of Dentistry, Hacettepe University, Ankara, Turkey.
J Endod. 2016 Nov;42(11):1673-1676. doi: 10.1016/j.joen.2016.08.002. Epub 2016 Sep 14.
The purpose of this study was to investigate the fracture resistance of roots by using intraorifice barriers with glass fiber-incorporated ProRoot MTA and Biodentine.
The diametral tensile strength and compressive strength of ProRoot MTA and Biodentine were determined after incorporation of 5 wt% and 10 wt% alkali resistant (AR) glass fiber powder into both cements. On the basis of higher diametral tensile strength and compressive strength values, ProRoot MTA and Biodentine with 5 wt% AR glass fiber were selected for further testing as intraorifice barriers. The 14-mm-long root specimens obtained from extracted mandibular premolars (n = 60) were prepared with nickel-titanium rotary files and obturated with gutta-percha + AH Plus sealer. After removal of coronal 3 mm of root fillings, the roots were grouped with respect to the intraorifice barrier material (n = 12/group): (1) ProRoot MTA, (2) ProRoot MTA with 5 wt% AR glass fibers, (3) Biodentine, (4) Biodentine with 5 wt% AR glass fibers, and (5) control (no intraorifice barrier). The specimens were loaded vertically at 1 mm/min crosshead speed until vertical root fracture occurred. The data were evaluated statistically by using 2-way analysis of variance and Tukey tests.
Both incorporation of glass fiber and the type of material significantly affected fracture resistance (both P = .002). Roots with glass fiber-reinforced Biodentine barriers showed the highest fracture strength (P = .000).
Incorporation of 5 wt% AR glass fiber can significantly improve the reinforcement effect of ProRoot MTA and Biodentine when used as intraorifice barriers.
本研究的目的是通过使用含有玻璃纤维的ProRoot MTA和Biodentine作为根管口屏障来研究牙根的抗折性。
将5 wt%和10 wt%的耐碱（AR）玻璃纤维粉末加入两种水门汀中，测定ProRoot MTA和Biodentine的径向拉伸强度和抗压强度。基于较高的径向拉伸强度和抗压强度值，选择含5 wt% AR玻璃纤维的ProRoot MTA和Biodentine作为根管口屏障进行进一步测试。从拔除的下颌前磨牙（n = 60）获得的14毫米长的牙根标本用镍钛旋转锉预备，并用牙胶尖+AH Plus封闭剂充填。去除根管冠方3毫米的根充物后，根据根管口屏障材料将牙根分组（n = 12/组）：（1）ProRoot MTA，（2）含5 wt% AR玻璃纤维的ProRoot MTA，（3）Biodentine，（4）含5 wt% AR玻璃纤维的Biodentine，（5）对照组（无根管口屏障）。标本以1毫米/分钟的十字头速度垂直加载，直至发生垂直牙根折断。数据采用双向方差分析和Tukey检验进行统计学评估。
玻璃纤维的加入和材料类型均显著影响抗折性（P均 = 0.002）。含玻璃纤维增强Biodentine屏障的牙根显示出最高的抗折强度（P = 0.000）。
当用作根管口屏障时，加入5 wt%的AR玻璃纤维可显著提高ProRoot MTA和Biodentine的增强效果。
