Bakirtzoglou Efpraxia, Kamalakidis Savvas N, Pissiotis Argirios L, Michalakis Konstantinos
Resident, Department of Prosthodontics, Aristotle University Faculty of Health Sciences, School of Dentistry, Thessaloniki, Greece.
Faculty, Department of Prosthodontics, Aristotle University Faculty of Health Sciences, School of Dentistry, Thessaloniki, Greece and Adjunct Assistant Professor, Division of Postgraduate Prosthodontics, Tufts University School of Dental Medicine, Boston, Mass.
J Clin Exp Dent. 2019 Mar 1;11(3):e225-e230. doi: 10.4317/jced.55566. eCollection 2019 Mar.
The purpose of this study was to evaluate the retention and resistance form of complete coverage restorations supported by two different cast post and core designs.
Forty extracted maxillary central incisors were randomly divided into four groups of 10 specimens each (namely A, B, C and D). All specimens were endodontically treated and a uniform post space of 9mm was created. All prepared teeth had a 360o chamfer ferrule of 2mm in axial height measured 0.5mm coronally from the cementoenamel junction (CEJ) and an axial wall thickness of 1.5 mm. Specimens in groups A and C received cast post and cores with the standardized core design, where the core ended at the coronal part of the ferrule, while specimens in groups B and D received cores that were encircling the ferrule. Cemented complete coverage restorations in groups A and B underwent tensile load stress, while the restorations in groups C and D underwent compressive load stress until failure.
Teeth in group A exhibited a mean failure load of 326.14±83.67 N under tension, while teeth in group B exhibited a mean failure load of 332.79±80.38 N (=0.858). Teeth in group C recorded a mean failure load of 1042.81±205.07 N, and in group D a mean failure load of 875.15±167.64 N (=0.061) under compression was registered.
The standard cast post and core design with a 2 mm of ferrule height offers superior resistance, although not statistically significant (=0.061), when compared to the core design encircling the axial wall ferrule. Both cast post and core designs offer equal retention. However, different failure modes of decementation were noted. Endodontically treated teeth, Post-and-core technique, Endodontic-post, Decementation, Root fracture, Ferrule effect.
本研究的目的是评估由两种不同铸造桩核设计支持的全冠修复体的固位和抗力形式。
40颗拔除的上颌中切牙随机分为四组,每组10个样本(即A、B、C和D组)。所有样本均进行根管治疗,并制备9mm的统一桩道。所有预备牙齿在距牙釉质牙骨质界(CEJ)冠方0.5mm处有一个轴向高度为2mm的360°肩台箍,轴向壁厚度为1.5mm。A组和C组的样本接受标准化桩核设计的铸造桩核,桩核在箍的冠部结束,而B组和D组的样本接受环绕箍的桩核。A组和B组的粘结全冠修复体承受拉伸载荷应力,而C组和D组的修复体承受压缩载荷应力直至破坏。
A组牙齿在拉伸时的平均破坏载荷为326.14±83.67N,而B组牙齿的平均破坏载荷为332.79±80.38N(P = 0.858)。C组牙齿在压缩时的平均破坏载荷为1042.81±205.07N,D组为875.15±167.64N(P = 0.061)。
与环绕轴向壁箍的桩核设计相比,具有2mm箍高度的标准铸造桩核设计提供了更好的抗力,尽管在统计学上无显著差异(P = 0.061)。两种铸造桩核设计提供了相等的固位力。然而,观察到不同的脱位失败模式。根管治疗牙齿、桩核技术、根管桩、脱位、根折、箍效应。