Kessler-Liechti Gerda, Zix Jürgen, Mericske-Stern Regina
Department of Prosthodontics, School of Dental Medicine, University of Bern, Bern, Switzerland.
Int J Oral Maxillofac Implants. 2008 Mar-Apr;23(2):353-8.
Resonance frequency analysis (RFA) is a method of measuring implant stability. However, little is known about RFA of implants with long loading periods. The objective of the present study was to determine standard implant stability quotients (ISQs) for clinical successfully osseointegrated 1-stage implants in the edentulous mandible.
Stability measurements by means of RFA were performed in regularly followed patients who had received 1- stage implants for overdenture support. The time interval between implant placement and measurement ranged from 1 year up to 10 years. The short-term group comprised patients who were followed up to 5 years, while the long-term group included patients with an observation time of > 5 years up to 10 years. For further comparison RFA measurements were performed in a matching group with unloaded implants at the end of the surgical procedure. For statistical analysis various parameters that might influence the ISQs of loaded implants were included, and a mixed-effects model applied (regression analysis, P <.0125).
Ninety-four patients were available with a total of 205 loaded implants, and 16 patients with 36 implants immediately after the surgical procedure. The mean ISQ of all measured implants was 64.5 +/- 7.9 (range, 58 to 72). Statistical analysis did not reveal significant differences in the mean ISQ related to the observation time. The parameters with overall statistical significance were the diameter of the implants and changes in the attachment level. In the short-term group, the gender and the clinically measured attachment level had a significant effect. Implant diameter had a significant effect in the long-term group.
A mean ISQ of 64.5 +/- 7.9 was found to be representative for stable asymptomatic interforaminal implants measured by the RFA instrument at any given time point. No significant differences in ISQ values were found between implants with different postsurgical time intervals. Implant diameter appears to influence the ISQ of interforaminal implants.
共振频率分析（RFA）是一种测量种植体稳定性的方法。然而，对于长期负载种植体的RFA了解甚少。本研究的目的是确定在下颌无牙区临床成功骨结合的一期种植体的标准种植体稳定性商数（ISQ）。
对接受一期种植体覆盖义齿支持且定期随访的患者进行RFA稳定性测量。种植体植入与测量之间的时间间隔为1年至10年。短期组包括随访至5年的患者，而长期组包括观察时间>5年至10年的患者。为了进一步比较，在手术结束时对一组未负载种植体进行RFA测量。统计分析纳入了可能影响负载种植体ISQ的各种参数，并应用了混合效应模型（回归分析，P<.0125）。
94例患者共有205个负载种植体，16例患者在手术后即刻有36个种植体。所有测量种植体的平均ISQ为64.5±7.9（范围，58至72）。统计分析未发现平均ISQ与观察时间相关的显著差异。具有总体统计学意义的参数是种植体直径和附着水平的变化。在短期组中，性别和临床测量的附着水平有显著影响。种植体直径在长期组中有显著影响。
发现平均ISQ为64.5±7.9代表在任何给定时间点通过RFA仪器测量的稳定无症状的孔间种植体。不同术后时间间隔的种植体之间未发现ISQ值有显著差异。种植体直径似乎影响孔间种植体的ISQ。
