Linkevicius Tomas, Puisys Algirdas, Steigmann Marius, Vindasiute Egle, Linkeviciene Laura
Institute of Odontology, Faculty of Medicine, Vilnius University, Vilnius, Lithuania.
Vilnius Research Group.
Clin Implant Dent Relat Res. 2015 Dec;17(6):1228-36. doi: 10.1111/cid.12222. Epub 2014 Mar 28.
Numerous studies have shown the superiority of platform-switched implants in preserving crestal bone as compared with platform-matched implants. However, the influence of initial soft tissue thickness on development of crestal bone loss has not been addressed in previous studies; thus, further research is needed.
To evaluate crestal bone levels around platform-switched implants placed in thin and thick mucosal tissue.
Eighty patients (38 male and 42 female, mean age 44 ± 3.34 years) received 80 bone-level implants of 4.1 mm in diameter with platform switching (Institut Straumann AG, Basel, Switzerland). Tissue thickness was measured, and cases were distributed to Group 1, with thin soft tissue (2 mm or less, n = 40), and Group 2, with thick tissue (more than 2 mm, n = 40). Implants were placed with a one-stage approach and restored with screw-retained restorations. Radiographic examination was performed after implant placement, 2 months after healing, after restoration, and at 1-year follow-up post-reconstruction. Crestal bone loss was calculated. The Mann-Whitney U-test was applied, and significance was set to p ≤ .05.
Implants in Group 1 (thin tissue) showed 0.79 mm of bone loss after 2 months. After 1-year follow-up, bone loss was 1.17 mm. Implants in Group 2 (thick tissue) showed bone loss of 0.17 mm after 2 months of implant placement and 0.21 mm after 1-year follow-up. The differences between groups were significant (p < .001) at both time points.
It can be concluded that platform switching does not prevent crestal bone loss if, at the time of implant placement, mucosal tissue is thin. In thick soft tissue, use of platform-switched implants maintained crestal bone level with minimal remodeling.
大量研究表明，与平台匹配种植体相比，平台转换种植体在保留嵴顶骨方面具有优越性。然而，先前的研究尚未探讨初始软组织厚度对嵴顶骨吸收的影响，因此需要进一步研究。
评估置于薄黏膜组织和厚黏膜组织中的平台转换种植体周围的嵴顶骨水平。
80例患者（38例男性，42例女性，平均年龄44±3.34岁）接受了80颗直径4.1mm的平台转换骨水平种植体（瑞士巴塞尔士卓曼集团）。测量组织厚度，并将病例分为两组，第1组为薄软组织（2mm或更薄，n = 40），第2组为厚组织（超过2mm，n = 40）。采用一期手术植入种植体，并用螺丝固位修复体进行修复。在种植体植入后、愈合2个月后、修复后以及重建后1年随访时进行影像学检查。计算嵴顶骨吸收量。应用曼-惠特尼U检验，显著性水平设定为p≤0.05。
第1组（薄组织）的种植体在2个月后骨吸收为0.79mm。1年随访后，骨吸收为1.17mm。第2组（厚组织）的种植体在植入2个月后骨吸收为0.17mm，1年随访后为0.21mm。两组在两个时间点的差异均具有显著性（p<0.001）。
可以得出结论，如果在植入种植体时黏膜组织较薄，平台转换并不能防止嵴顶骨吸收。在厚软组织中，使用平台转换种植体可使嵴顶骨水平保持在最小程度的改建状态。
