Hunter A J, Hunter A R
J Prosthet Dent. 1990 Dec;64(6):636-42. doi: 10.1016/0022-3913(90)90286-l.
While there is variation regarding the maximum acceptable marginal discrepancy, there is little argument that poorly fitting margins are a frequent finding. Large discrepancies are clinically significant, since they facilitate plaque retention. Margins incorporating slip joint geometry have usually been favored as a method of minimizing seating and sealing discrepancies. However, many of these discussions largely ignored the effects of the cementing medium and the clinical applicability of slip joint geometry is based on questionable assumptions with regard to casting accuracy and seating. Greater understanding of the role of restorative margins and gingival health indicates the need for shallow margin placement within the crevice, which requires a reassessment of the use of long bevels. Horizontal margins can be made accurately and, when combined with procedures to maximize crown seating, may provide the best method of minimizing seating discrepancies and maximizing gingival health.
虽然对于最大可接受边缘差异存在不同看法，但几乎没有争议的是，边缘贴合不佳是常见的情况。大的差异具有临床意义，因为它们便于菌斑滞留。采用滑动关节几何形状的边缘通常被视为一种使就位和密封差异最小化的方法。然而，这些讨论大多在很大程度上忽略了粘结介质的影响，并且滑动关节几何形状的临床适用性是基于关于铸造精度和就位的可疑假设。对修复边缘与牙龈健康作用的更深入理解表明，需要在龈沟内进行浅边缘放置，这就需要重新评估长斜面的使用。水平边缘可以精确制作，并且当与使牙冠就位最大化的程序相结合时，可能提供使就位差异最小化并使牙龈健康最大化的最佳方法。
