Teixeira Erica C N, Teixeira Fabricio B, Piasick Jeffrey R, Thompson Jeffery Y
Department of Diagnostic Sciences and General Dentitsry, University of North Carolina School of Dentistry, CB #7450, Chapel Hill, 27599-7450, USA.
J Am Dent Assoc. 2006 Jul;137(7):1006-12. doi: 10.14219/jada.archive.2006.0323.
The authors conducted a study to characterize the in vitro retention, fracture and light transmission behavior of four different fiber-reinforced resin-based composite root canal posts.
The authors divided 44 teeth into four groups according to the type of post they would receive: parallel fiberglass posts, double-tapered fiber quartz posts, tapered fiberglass posts and two different types of parallel fiberglass posts. They prepared teeth and cemented posts with dual-cured resin cement. After the specimens aged, the authors conducted pull-out tests. For fracture testing, they loaded posts at 45 degrees in a universal testing machine. They determined load-to-fracture values and relative stiffness. They measured percentage of light transmission by means of a light microscope coupled with a spectrometer.
Both tapered posts showed lower retention than did the parallel posts. Scanning electron microscropic analysis indicated that more cement adhered to the surfaces of the parallel fiberglass post than to those of the tapered fiberglass post. All posts demonstrated some plastic behavior, with the double-tapered fiber quartz post being stiffer than the others.
Parallel fiber-reinforced composite posts showed better retention than did tapered posts when a dual-cured resin-based cement was used. Translucent prefabricated posts have limited light transmission.
Parallel prefabricated fiber posts luted with dual-cured resin-based cement seem to be suitable for clinical application in endodontically treated teeth that require post-and-core restoration, showing good retention and acceptable fracture resistance.
作者开展了一项研究,以描述四种不同纤维增强树脂基复合根管桩的体外固位、断裂及透光性能。
作者根据所使用桩的类型将44颗牙齿分为四组:平行玻璃纤维桩、双锥度纤维石英桩、锥度玻璃纤维桩以及两种不同类型的平行玻璃纤维桩。他们对牙齿进行预备并用双固化树脂水门汀粘结桩。在样本老化后,作者进行拔出试验。对于断裂测试,他们在万能试验机上以45度角加载桩。他们测定断裂载荷值和相对刚度。他们通过与光谱仪联用的光学显微镜测量透光百分比。
两种锥度桩的固位力均低于平行桩。扫描电子显微镜分析表明,平行玻璃纤维桩表面粘结的水门汀比锥度玻璃纤维桩表面更多。所有桩均表现出一定的塑性行为,双锥度纤维石英桩比其他桩更硬。
当使用双固化树脂基水门汀时,平行纤维增强复合桩的固位力比锥度桩更好。半透明预制桩的透光性有限。
用双固化树脂基水门汀粘结的平行预制纤维桩似乎适用于需要桩核修复的根管治疗牙齿的临床应用,显示出良好的固位力和可接受的抗折性。