Department of Prosthodontics, Seoul St. Mary's Dental Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Int J Oral Maxillofac Implants. 2009 Nov-Dec;24(6):1061-7.
The purpose of this study was to evaluate the clinical efficacy of implant prostheses retained by screws and cement (SCPs) by examining the reverse torque values (RTVs) of the abutment screws and the marginal openings of the implant prostheses.
Two implants (3.8 x 13 mm; Camlog Biotechnologies) were embedded in an acrylic resin block 5 mm apart. Eighteen copies of this resin specimen were fabricated and randomly divided into two groups. Two-unit implant prostheses with two different designs-purely cement-retained implant prostheses (group 1) and SCPs (group 2)-were made out of type IV gold alloy and placed on the implants. After tightening to about 30 Ncm, the preloading RTVs of the abutment screws were measured. After retightening the abutment screws or cementing the prostheses, followed by cyclic loading, the postloading RTVs of the abutment screws were examined. Also, the marginal openings of the prostheses in the two groups were measured under a stereomicroscope. These measurements were compared statistically.
The postloading RTVs and their differences from the preloading RTVs of the abutment screws demonstrated no significant differences between groups (P > .05). Group 2 prostheses showed significantly smaller marginal openings than group 1 prostheses (P < .05).
The forces generated when torquing the abutment screw of the SCP did not cause more loosening of the abutment screws than the purely cement-retained implant prosthesis. The SCP showed better marginal adaptation of the cement-retained part than the purely cement-retained implant prosthesis, possibly as a result of the screw-retained abutment seating the restoration. Within the limitations of this in vitro test, the SCP showed no significant difference in RTV of the abutment screw and a smaller marginal gap compared to a purely cement-retained implant prosthesis.
本研究旨在通过检查基台螺钉的反向扭矩值（RTV）和种植体修复体的边缘间隙，评估螺钉固位和粘结固位种植体修复体的临床疗效。
将两个种植体（3.8 x 13mm；Camlog Biotechnologies）分别嵌入相距 5mm 的丙烯酸树脂块中。制作了 18 个这种树脂标本，并将其随机分为两组。制作两种不同设计的 2 单位种植体修复体-纯粘结固位种植体修复体（组 1）和螺钉固位粘结固位种植体修复体（组 2）-使用 IV 型金合金，并放置在种植体上。在拧紧至约 30Ncm 后，测量基台螺钉的预加载 RTV。在重新拧紧基台螺钉或粘结修复体后，进行循环加载，检查基台螺钉的后加载 RTV。同时，在体视显微镜下测量两组修复体的边缘间隙。对这些测量值进行统计学比较。
基台螺钉的后加载 RTV 及其与预加载 RTV 的差值在两组之间无显著差异（P＞.05）。组 2 修复体的边缘间隙明显小于组 1 修复体（P＜.05）。
在拧紧螺钉固位粘结固位种植体修复体的基台螺钉时产生的力不会导致基台螺钉比纯粘结固位种植体修复体更容易松动。与纯粘结固位种植体修复体相比，螺钉固位粘结固位种植体修复体的粘结部分具有更好的边缘适应性，这可能是由于螺钉固位基台使修复体就位。在本体外试验的限制范围内，与纯粘结固位种植体修复体相比，螺钉固位粘结固位种植体修复体的基台螺钉 RTV 无显著差异，边缘间隙较小。
