Jemt Torsten, Häger Per
The Brånemark Clinic, Public Dental Health Service, Göteborg, Sweden.
Clin Implant Dent Relat Res. 2006;8(2):77-86. doi: 10.1111/j.1708-8208.2006.00002.x.
Clusters of implant failures in the edentulous maxilla seem to occur in some patients. To create groups for analysis with higher numbers of these patients implies large original groups for inclusion.
The aim of this study was to retrospectively describe and compare a group of "cluster failure patients" with randomly selected patients treated in the edentulous maxilla.
From a group of 1,267 consecutively treated patients in one clinic, all patients presenting failing fixed implant-supported prostheses within the first 3 years of follow-up were included. All patients were treated with turned titanium implants using two-stage surgery. A control group of equal number of patients were created for comparison. Data on patients were retrospectively retrieved from their records, and compared.
Seventeen patients (1.3%) met the inclusion criteria in the entire group. The bone resorption index revealed less bone quantity in the study group (p < .05) during implant placement, but there was no difference regarding primary implant stability at first-stage surgery. The distribution of short and long implants showed relatively higher number of short implants in the study group (p < .05), and more patients had a presurgical discussion on the risk of implant failure prior to treatment in this group (p < .05). Only 5 out of 102 implants (4.9%) were lost before prosthesis placement as compared to 38 and 25 lost implants during the following two years in the study group. Smoking habits and signs of bone loss related to periodontitis in the lower dentition were more frequent in the study group, but did not reach a significant level (p > .05).
The results indicate that bone quantity, reflected in fixture length, has a significant impact on increased implant failure risk. Other factors of interest as predictors for implant failures could be smoking habits and also possibly signs of periodontitis in the opposing dentition.
无牙上颌骨种植体失败的情况似乎在部分患者中出现。为了创建数量更多的此类患者群体进行分析，意味着需要纳入大量的原始群体。
本研究的目的是回顾性描述并比较一组“种植体失败集群患者”与在上颌无牙区接受治疗的随机选择患者。
从一家诊所连续治疗的1267例患者中，纳入所有在随访的前3年内出现固定种植体支持修复体失败的患者。所有患者均采用两段式手术植入车削钛种植体。创建了一个数量相等的对照组进行比较。回顾性地从患者记录中获取患者数据并进行比较。
在整个群体中，17例患者（1.3%）符合纳入标准。骨吸收指数显示，在种植体植入期间，研究组的骨量较少（p < 0.05），但在一期手术时，初始种植体稳定性方面没有差异。短种植体和长种植体的分布显示，研究组中短种植体数量相对较多（p < 0.05），并且该组中更多患者在治疗前就种植体失败风险进行了术前讨论（p < 0.05）。在研究组中，与对照组相比，在修复体植入前，102颗种植体中仅有5颗（4.9%）丢失，而在接下来的两年中分别有38颗和25颗种植体丢失。研究组中吸烟习惯以及下牙列与牙周炎相关的骨丢失迹象更为常见，但未达到显著水平（p > 0.05）。
结果表明，种植体长度所反映的骨量对种植体失败风险增加有显著影响。作为种植体失败预测指标的其他因素可能包括吸烟习惯以及对颌牙列中可能存在的牙周炎迹象。
