Mamoun John S
DMD, Private Practice, Manalapan, NJ USA.
Eur J Dent. 2014 Apr;8(2):281-286. doi: 10.4103/1305-7456.130639.
An abutment for a fixed partial denture may not contain enough tooth structure, such that the abutment does not provide an adequate 'ferrule effect'. A crown or bridge dental prosthesis that is cemented onto such an abutment/s may undergo biomechanical failure. Here, the tooth, core, and post complex, on which the crown is cemented, may fracture off from the abutment, causing the crown to separate from the abutment, while the cement that bonds the crown to the tooth, core, and post complex remains intact, such that the tooth, core, and post complex remains inside the crown when the crown separates from the abutment. This article reviews the dentistry literature on the ferrule effect, and presents alternative definitions for terms such as ferrule, the ferrule effect, and the ferrule tooth structure. The article also explains how the use of a surgical operating microscope, or high magnification binocular surgical loupes of ×6-8, or greater magnification improve the ability of a dentist to assess how much ferrule tooth structure an abutment contains, compared to the use of unaided vision.
固定局部义齿的基牙可能没有足够的牙体组织，以至于基牙无法提供足够的“箍效应”。粘结在这种基牙上的冠或桥修复体可能会发生生物力学失败。在此情况下，粘结有冠的牙、核和桩复合体可能会从基牙上折断，导致冠与基牙分离，而将冠粘结到牙、核和桩复合体上的粘结剂仍保持完整，使得当冠与基牙分离时，牙、核和桩复合体仍留在冠内。本文回顾了牙科文献中关于箍效应的内容，并给出了诸如箍、箍效应和箍牙体结构等术语的替代定义。文章还解释了与 unaided vision 相比，使用手术操作显微镜、放大倍数为×6 - 8 或更大的高倍双目手术放大镜如何提高牙医评估基牙所含箍牙体结构量的能力。
