Dental School, University of Chieti, Chieti, Italy.
Clin Implant Dent Relat Res. 2012 Aug;14(4):501-7. doi: 10.1111/j.1708-8208.2010.00302.x. Epub 2010 Sep 17.
The aims of the present study are to evaluate the primary stability of a sample of 4,135 implants and to investigate the correlations between primary stability and mechanical characteristic of the implant and bone density at insertion time.
The study was conducted from March 2002 to January 2009 at a private practice in Bologna (Italy). Patients were eligible for the study if they needed the insertion of single or multiple implants. Bone density, length, and diameter of each implant were recorded. During surgery for each implant, peak insertion torque (IT) was recorded; the resonance frequency analysis (RFA) values were also collected. Finally, it was recorded whether an implant was lost or removed at an early stage (within 6months from insertion surgery).
A total of 1,045 consecutive patients were included in the study. A total of 4,135 of implants were inserted. The sample presented 1,184 implants inserted in a postextractive site. The mean peak IT was 34.82±19.36. The mean RFA was 71.57±10.63 implant stability quotient. Spearman correlation analysis shows the presence of a weak positive correlation between IT and RFA. The statistical analysis shows a relevant dependency between IT and bone quality and a very weak dependency between RFA and bone quality. Again, the statistical analysis shows a quite weak correlation between length or diameter and IT, but it shows a relevant correlation between length and RFA. Postextractive implants presented a higher mean IT and a lower RFA compared with implants inserted in healed sites. Twenty-eight (0.7%) implants were considered to have failed and removed within 6months.
The results show that the implants studied obtain a good primary stability with a standard protocol. The IT and RFA appear as two independent features of primary stability. Data show that only IT is influenced by bone density as well as only RFA is correlated to the length of implants used. Finally, it is possible to obtain a good primary stability also in postextractive sites.
本研究旨在评估 4135 例样本种植体的初期稳定性，并研究种植体初期稳定性与机械特性以及植入时骨密度之间的相关性。
本研究于 2002 年 3 月至 2009 年 1 月在意大利博洛尼亚的一家私人诊所进行。如果患者需要植入单个或多个种植体，则符合研究条件。记录了每个种植体的骨密度、长度和直径。在每个种植体的手术过程中，记录了峰值种植体扭矩（IT）；还收集了共振频率分析（RFA）值。最后，记录了种植体是否在早期（植入手术后 6 个月内）丢失或取出。
共有 1045 名连续患者纳入研究。共植入 4135 例种植体。该样本中有 1184 例种植体植入了拔牙窝。平均峰值 IT 为 34.82±19.36。平均 RFA 为 71.57±10.63 种植体稳定性系数。Spearman 相关分析显示 IT 和 RFA 之间存在弱正相关。统计分析表明 IT 与骨质量之间存在显著依赖性，而 RFA 与骨质量之间存在非常弱的依赖性。同样，统计分析表明 IT 与长度或直径之间的相关性较弱，但与 RFA 之间的相关性较强。与愈合部位植入的种植体相比，拔牙窝中植入的种植体具有更高的平均 IT 和更低的 RFA。28 例（0.7%）种植体被认为在 6 个月内失效并取出。
结果表明，研究中使用的种植体采用标准方案获得了良好的初期稳定性。IT 和 RFA 似乎是初期稳定性的两个独立特征。数据表明，只有 IT 受骨密度的影响，只有 RFA 与使用的种植体长度相关。最后，在拔牙窝中也可以获得良好的初期稳定性。
