Harvard School of Dental Medicine, Boston, Massachusetts, USA.
Int J Oral Maxillofac Implants. 2011 Jul-Aug;26(4):850-9.
This study was undertaken to assess the predictive usefulness of preoperative bone density, as measured by computed tomography (CT), and the intraoperative implant stability measures of insertion torque (IT), Periotest values (PTV), and resonance frequency analysis (ie, implant stability quotient [ISQ]) toward developing an algorithm for successful immediate loading, one-step exposure, or submergence of dental implants.
Consecutively presenting patients requesting immediate loading in areas other than the anterior mandible were analyzed retrospectively. The implants were either immediately loaded, left exposed, or submerged on the basis of preoperative CT bone density and intraoperative primary stability measures. All implants surviving the traditional healing period were verified for osseointegration.
Eighteen patients were analyzed retrospectively, and they received 58 implants. Seven implants failed, for a survival rate of 88%. Primary stability measurements at insertion were correlated with one another and with preoperative CT bone density. Preoperative mean bone density for surviving implants was greatest for immediately loaded implants (983 ± 83), lower for exposed implants (803 ± 29), and lowest (480 ± 23) for submerged implants. Bone density was significantly different between submerged implants that failed and those that survived. Mean IT for successful implants was higher than for those that failed. Mean PTVs were lower (ie, better) for successful versus failed implants, although this difference was significant only for submerged implants.
In this group of patients, objective measures of bone density by CT, IT, PTV, and ISQ correlated with each other and therefore may provide a useful algorithm for making clinical implant loading decisions. Of the technologies applied in this group of patients, PTV was the most reliable predictor at implant placement of failure to osseointegrate.
本研究旨在评估术前 CT 测量的骨密度以及术中种植体稳定性指标（即插入扭矩[IT]、Periotest 值[PTV]和共振频率分析[即种植体稳定性比[ISQ]）对开发一种成功的即刻负载、一步暴露或种植体淹没的算法的预测有用性。
回顾性分析了连续出现的要求在前颌骨以外区域即刻负载的患者。根据术前 CT 骨密度和术中初级稳定性测量值，将种植体即刻加载、暴露或淹没。所有在传统愈合期存活的种植体均进行骨整合验证。
18 名患者被回顾性分析，共植入 58 枚种植体。7 枚种植体失败，存活率为 88%。植入时的初级稳定性测量值相互之间以及与术前 CT 骨密度相关。存活种植体的术前平均骨密度以即刻加载种植体最高（983±83），暴露种植体次之（803±29），淹没种植体最低（480±23）。骨密度在失败和存活的淹没种植体之间存在显著差异。成功种植体的平均 IT 高于失败种植体。成功种植体的平均 PTV 低于（即更好）失败种植体，尽管这种差异仅在淹没种植体中具有统计学意义。
在这群患者中，CT、IT、PTV 和 ISQ 等客观骨密度测量值相互之间存在相关性，因此可能为临床种植体负载决策提供有用的算法。在这群患者中应用的技术中，PTV 是在种植体植入时预测骨整合失败的最可靠指标。
