1 Clinic of Fixed and Removable Prosthodontics and Dental Material Science, University of Zurich, Zurich, Switzerland.
2 Clinic of Preventive Dentistry, Periodontology and Cariology, Center of Dental Medicine, University of Zurich, Zurich, Switzerland.
J Dent Res. 2018 Jul;97(8):887-892. doi: 10.1177/0022034518758036. Epub 2018 Mar 13.
The aim of the present study was to evaluate whether 6-mm dental implants in the posterior segments of either jaw perform equally well in terms of clinical and radiographic outcomes when compared with 10-mm implants after 5 y of loading. Patients with single-tooth gaps in the posterior area who were scheduled for implant therapy were randomly assigned to a group receiving either a 6- or 10-mm implant. After a healing period of 10 wk, implants were loaded with a screw-retained single crown and followed up at yearly intervals. Of 96 patients, 86 could be recalled after 5 y. The implant survival rates amounted to 91% (95% confidence interval: 0.836 to 0.998) for the 6-mm group and 100% for the 10-mm group ( P = 0.036). Median crown-to-implant (C/I) ratios were 1.75 (interquartile range [IQR], 1.50 to 1.90) for the 6-mm group and 1.04 (IQR, 0.95 to 1.15) for the 10-mm group, whereas the median marginal bone levels measured -0.29 mm (IQR, -0.92 to 0.23) for the 6-mm group and -0.15 mm (IQR: -0.93 - 0.41) for the 10-mm group after 5 y. The C/I ratio turned out to be statistically significant ( P < 0.001), whereas marginal bone levels showed no significant difference between the groups. The 6-mm implants exhibited significantly lower survival rates than the 10-mm implants over 5 y, whereas there was no difference between upper and lower jaws in terms of survival ( P = 0.58). Lost implants did not show any sign of marginal bone loss or peri-implant infection previous to loss of osseointegration. High C/I ratio and implant length had no significant effect on marginal bone level changes or technical and biological complications (German Clinical Trials Registry: DRKS00006290).
本研究旨在评估在后牙区植入 6mm 和 10mm 种植体 5 年的临床和影像学效果是否相当。将计划接受种植体治疗的后牙区单个牙缺失患者随机分为植入 6mm 或 10mm 种植体的两组。愈合期 10 周后，用螺丝固位的单冠负载种植体，并在每年随访一次。96 例患者中，86 例在 5 年后可召回。6mm 组的种植体存活率为 91%（95%置信区间：0.836 至 0.998），10mm 组为 100%（P=0.036）。6mm 组的冠根比中位数为 1.75（四分位间距[IQR]：1.50 至 1.90），10mm 组为 1.04（IQR：0.95 至 1.15），而 6mm 组的中位边缘骨水平在 5 年后测量为-0.29mm（IQR：-0.92 至 0.23），10mm 组为-0.15mm（IQR：-0.93 至 0.41）。C/I 比值具有统计学意义（P<0.001），而边缘骨水平在两组间无显著差异。6mm 种植体的 5 年存活率明显低于 10mm 种植体，而上、下颌骨的存活率无差异（P=0.58）。失牙前无种植体边缘骨丧失或种植体周围感染迹象。高 C/I 比值和种植体长与边缘骨水平变化、技术和生物学并发症无关（德国临床试验注册处：DRKS00006290）。
