Department of Restorative Dental Sciences and Center for Dental Biomaterials, University of Florida College of Dentistry, Gainesville, FL 32610, USA.
J Prosthodont. 2013 Apr;22(3):166-73. doi: 10.1111/j.1532-849X.2012.00913.x. Epub 2012 Sep 14.
Analyzing the clinical performance of restorative materials is important, as there is an expectation that these materials and procedures will restore teeth and do no harm. The objective of this research study was to characterize the clinical performance of metal-ceramic crowns, core ceramic crowns, and core ceramic/veneer ceramic crowns based on 11 clinical criteria.
An IRB-approved, randomized, controlled clinical trial was conducted as a single-blind pilot study. The following three types of full crowns were fabricated: (1) metal-ceramic crown (MC) made from a Pd-Au-Ag-Sn-In alloy (Argedent 62) and a glass-ceramic veneer (IPS d.SIGN veneer); (2) non-veneered (glazed) lithium disilicate glass-ceramic crown (LDC) (IPS e.max Press core and e.max Ceram Glaze); and (3) veneered lithia disilicate glass-ceramic crown (LDC/V) with glass-ceramic veneer (IPS Empress 2 core and IPS Eris). Single-unit crowns were randomly assigned. Patients were recalled for each of 3 years and were evaluated by two calibrated clinicians. Thirty-six crowns were placed in 31 patients. A total of 12 crowns of each of the three crown types were studied. Eleven criteria were evaluated: tissue health, marginal integrity, secondary caries, proximal contact, anatomic contour, occlusion, surface texture, cracks/chips (fractures), color match, tooth sensitivity, and wear (of crowns and opposing enamel). Numerical rankings ranged from 1 to 4, with 4 being excellent, and 1 indicating a need for immediate replacement. Statistical analysis of the numerical rankings was performed using a Fisher's exact test.
There was no statistically significant difference between performance of the core ceramic crowns and the two veneered crowns at year 1 and year 2 (p > 0.05). All crowns were rated either as excellent or good for each of the clinical criteria; however, between years 2 and 3, gradual roughening of the occlusal surface occurred in some of the ceramic-ceramic crowns, possibly caused by dissolution and wear of the glaze. Statistically significant differences in surface texture (p= 0.0013) and crown wear (p= 0.0078) were found at year 3 between the metal-ceramic crowns and the lithium-disilicate-based crowns.
Based on the 11 criteria, the clinical performance of ceramic-ceramic crowns was comparable to that of the metal-ceramic crowns after 2 years; however, gradual roughening occurred between years 2 and 3, which resulted in differences in surface texture and wear.
分析修复材料的临床性能非常重要，因为人们期望这些材料和程序既能修复牙齿又不会造成伤害。本研究的目的是根据 11 项临床标准来描述金属陶瓷冠、核陶瓷冠和核陶瓷/贴面陶瓷冠的临床性能。
进行了一项经 IRB 批准的、随机的、对照的临床试验，作为单盲试点研究。制作了以下三种全冠：（1）由 Pd-Au-Ag-Sn-In 合金（Argedent 62）和玻璃陶瓷贴面（IPS d.SIGN 贴面）制成的金属陶瓷冠（MC）；（2）无贴面（上釉）锂硅玻璃陶瓷冠（LDC）（IPS e.max Press 核和 e.max Ceram Glaze）；和（3）用玻璃陶瓷贴面（IPS Empress 2 核和 IPS Eris）制成的贴面锂硅玻璃陶瓷冠（LDC/V）。单单位冠随机分配。患者在 3 年内每次都被召回，并由两位经过校准的临床医生进行评估。共有 31 名患者接受了 36 个牙冠的治疗。研究了三种牙冠类型中的每种类型的 12 个牙冠。评估了 11 个标准：组织健康、边缘完整性、继发龋、近中接触、解剖轮廓、咬合、表面纹理、裂缝/碎裂（断裂）、颜色匹配、牙齿敏感和磨损（牙冠和对颌牙釉质）。数值等级从 1 到 4，4 表示优秀，1 表示需要立即更换。使用 Fisher 精确检验对数值等级进行了统计分析。
在第 1 年和第 2 年，核陶瓷冠和两种贴面冠的性能没有统计学差异（p>0.05）。所有牙冠在每一项临床标准中均被评为优秀或良好；然而，在第 2 年和第 3 年之间，一些陶瓷陶瓷冠的牙合面出现了逐渐变粗糙的情况，可能是由于釉质的溶解和磨损所致。在第 3 年，金属陶瓷冠和锂硅基冠之间在表面纹理（p=0.0013）和牙冠磨损（p=0.0078）方面存在统计学显著差异。
根据 11 项标准，在 2 年后，陶瓷陶瓷冠的临床性能可与金属陶瓷冠相媲美；然而，在第 2 年和第 3 年之间出现了逐渐变粗糙的情况，导致了表面纹理和磨损方面的差异。
