Griffith University, School of Dentistry and Oral Health, Gold Coast, Australi.
J Prosthodont. 2013 Jul;22(5):419-28. doi: 10.1111/jopr.12006. Epub 2013 Jan 4.
To review methods used to investigate marginal adaptation of crowns and fixed dental prostheses (FDPs), and to discuss testing variables employed and their influence on results.
Online libraries including PubMed, Scopus, and Ovid were searched for articles evaluating the marginal adaptation of crowns and FDPs using a combination of the keywords: "marginal accuracy," "marginal fit," "marginal gap," "marginal discrepancy," "fitting accuracy," "crown," and "FPD." Peer-reviewed publications in English in the period 1970 to December 2011 were collected, evaluated by their abstract, and included if they met the inclusion criteria. The criteria involved studies evaluating marginal adaptation of crowns and FDPs through clear experimental protocols. Exclusion criteria involved longitudinal prospective and retrospective clinical evaluations, studies using subjective tactile sensation, and other predefined criteria.
A total of 277 papers were identified; only 183 met the inclusion criteria. Direct view technique was used by 47.5% of the articles followed by cross-sectioning (23.5%), and impression replica (20.2%) techniques. The marginal gap values reported by these techniques varied among individual crown systems and across different systems because of variations in study type (in vivo vs. in vitro), sample size and measurements per specimen, finish line design, and stage at which the marginal gap was measured.
There was a substantial lack of consensus relating to marginal adaptation of various crown systems due to differences in testing methods and experimental protocols employed. Direct view technique was the most commonly used method of reproducible results. Also, conducting an experimental set-up of testing a minimum of 30 specimens at 50 measurements per specimen should produce reliable results. Additionally, using a combination of two measurement methods can be useful in verification of results.
回顾研究冠和固定义齿（FDP）边缘适合性的方法，并讨论所采用的测试变量及其对结果的影响。
通过组合使用关键词“边缘精度”、“边缘拟合”、“边缘间隙”、“边缘差异”、“拟合精度”、“冠”和“FPD”，在 PubMed、Scopus 和 Ovid 等在线文库中搜索评估冠和 FDP 边缘适合性的文章。收集了 1970 年至 2011 年 12 月期间以英语发表的同行评审的出版物，并根据其摘要进行评估，如果符合纳入标准则予以纳入。纳入标准涉及通过明确的实验方案评估冠和 FDP 边缘适合性的研究。排除标准包括纵向前瞻性和回顾性临床评估、使用主观触觉的研究以及其他预定义标准。
共确定了 277 篇论文，只有 183 篇符合纳入标准。有 47.5%的文章采用直接观察技术，其次是横断面（23.5%）和印模复制（20.2%）技术。由于研究类型（体内与体外）、样本量和每个样本的测量次数、边缘线设计以及测量边缘间隙的阶段不同，这些技术报告的边缘间隙值在不同的冠系统之间存在差异。
由于所采用的测试方法和实验方案不同，各种冠系统的边缘适应情况存在很大差异，因此缺乏共识。直接观察技术是最常用的可重复结果的方法。此外，进行至少 30 个样本、每个样本 50 次测量的实验设置可以产生可靠的结果。此外，结合使用两种测量方法可以有助于验证结果。
