Esposito Marco, Grusovin Maria Gabriella, Polyzos Ilias P, Felice Pietro, Worthington Helen V
Department of Oral and Maxillofacial Surgery, School of Dentistry, The University of Manchester, Coupland 3 Building, Oxford Road, Manchester, UK, M13 9PL.
Cochrane Database Syst Rev. 2010 Sep 8;2010(9):CD005968. doi: 10.1002/14651858.CD005968.pub3.
'Immediate' implants are placed in dental sockets just after tooth extraction. 'Immediate-delayed' implants are those implants inserted after weeks up to about a couple of months to allow for soft tissue healing. 'Delayed' implants are those placed thereafter in partially or completely healed bone. The potential advantages of immediate implants are that treatment time can be shortened and that bone volumes might be partially maintained thus possibly providing good aesthetic results. The potential disadvantages are an increased risk of infection and failures. After implant placement in postextractive sites, gaps can be present between the implant and the bony walls. It is possible to fill these gaps and to augment bone simultaneously to implant placement. There are many techniques to achieve this but it is unclear when augmentation is needed and which could be the best augmentation technique.
To evaluate success, complications, aesthetics and patient satisfaction between 'immediate', 'immediate-delayed' and 'delayed' implants.To evaluate whether and when augmentation procedures are necessary and which is the most effective technique.
The Cochrane Oral Health Group's Trials Register (to 2 June 2010), CENTRAL (The Cochrane Library 2010, Issue 2), MEDLINE via OVID (1950 - 2 June 2010) and EMBASE via OVID (1980 - 2 June 2010) were searched. Several dental journals were handsearched.
Randomised controlled trials (RCTs) comparing immediate, immediate-delayed, and delayed implants, or comparing various bone augmentation procedures around the inserted implants, reporting the outcome of the interventions to at least 1 year after functional loading.
Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted independently and in duplicate. Trial authors were contacted for any missing information. Results were expressed as random-effects models using mean differences for continuous outcomes and risk ratios (RR) for dichotomous outcomes with 95% confidence intervals (CIs). The statistical unit of the analysis was the patient.
Fourteen eligible RCTs were identified but only seven trials could be included. Four RCTs evaluated implant placement timing. Two RCTs compared immediate versus delayed implants in 126 patients and found no statistically significant differences. One RCT compared immediate-delayed versus delayed implants in 46 patients. After 2 years patients in the immediate-delayed group perceived the time to functional loading significantly shorter, were more satisfied and independent blinded assessor judged the level of the perimplant marginal mucosa in relation to that of the adjacent teeth as more appropriate (RR = 1.68; 95% CI 1.04 to 2.72). These differences disappeared 5 years after loading but significantly more complications occurred in the immediate-delayed group (RR = 4.20; 95% CI 1.01 to 17.43). One RCT compared immediate with immediately delayed implants in 16 patients for 2 years and found no differences. Three RCTs evaluated different techniques of bone grafting for implants immediately placed in extraction sockets. No statistically significant difference was observed when evaluating whether autogenous bone is needed in postextractive sites (1 trial with 26 patients) or which was the most effective augmentation technique (2 trials with 56 patients).
AUTHORS' CONCLUSIONS: There is insufficient evidence to determine possible advantages or disadvantages of immediate, immediate-delayed or delayed implants, therefore these preliminary conclusions are based on few underpowered trials often judged to be at high risk of bias. There is a suggestion that immediate and immediate-delayed implants may be at higher risks of implant failures and complications than delayed implants on the other hand the aesthetic outcome might be better when placing implants just after teeth extraction. There is not enough reliable evidence supporting or refuting the need for augmentation procedures at immediate implants placed in fresh extraction sockets or whether any of the augmentation techniques is superior to the others.
“即刻”种植体在拔牙后立即植入牙槽窝。“即刻-延期”种植体是指在拔牙后数周直至约两个月后植入的种植体，以便软组织愈合。“延期”种植体则是在部分或完全愈合的骨组织中随后植入的种植体。即刻种植体的潜在优势在于可以缩短治疗时间，并且可能部分维持骨量，从而有可能获得良好的美学效果。潜在的缺点是感染和失败的风险增加。在拔牙后部位植入种植体后，种植体与骨壁之间可能会出现间隙。在植入种植体的同时填充这些间隙并增加骨量是可行的。有许多技术可以实现这一点，但尚不清楚何时需要骨增量以及哪种骨增量技术可能是最佳的。
评估“即刻”、“即刻-延期”和“延期”种植体在成功率、并发症、美学效果和患者满意度方面的差异。评估是否以及何时需要进行骨增量程序以及哪种技术最有效。
检索了Cochrane口腔健康组试验注册库（截至2010年6月2日）、CENTRAL（Cochrane图书馆2010年第2期）、通过OVID检索的MEDLINE（1950年 - 2010年6月2日）以及通过OVID检索的EMBASE（1980年 - 2010年6月2日）。还手工检索了几本牙科杂志。
随机对照试验（RCT），比较即刻、即刻-延期和延期种植体，或比较植入种植体周围的各种骨增量程序，报告功能加载后至少1年的干预结果。
对符合条件的研究进行筛选、评估试验的方法学质量并独立且重复地提取数据。就任何缺失信息与试验作者进行了联系。结果以随机效应模型表示，连续结果使用均值差，二分结果使用风险比（RR）并带有95%置信区间（CI）。分析的统计单位是患者。
共识别出14项符合条件的RCT，但仅纳入了7项试验。4项RCT评估了种植体植入时机。2项RCT比较了126例患者的即刻种植与延期种植，未发现统计学上的显著差异。1项RCT比较了46例患者的即刻-延期种植与延期种植。2年后，即刻-延期组的患者感觉达到功能加载的时间明显更短，更满意，且独立的盲法评估者判断种植体周围边缘黏膜相对于相邻牙齿的水平更合适（RR = 1.68；95% CI 1.04至2.72）。这些差异在加载后5年消失，但即刻-延期组出现了明显更多的并发症（RR = 4.20；95% CI 1.01至17.43）。1项RCT对16例患者的即刻种植与即刻-延期种植进行了2年比较，未发现差异。3项RCT评估了立即植入拔牙窝的种植体的不同骨移植技术。在评估拔牙后部位是否需要自体骨（1项试验，26例患者）或哪种骨增量技术最有效（2项试验，56例患者）时，未观察到统计学上的显著差异。
没有足够的证据来确定即刻、即刻-延期或延期种植体可能的优势或劣势，因此这些初步结论基于少数功效不足的试验，这些试验通常被判定存在较高的偏倚风险。有迹象表明，即刻和即刻-延期种植体可能比延期种植体有更高的种植失败和并发症风险，另一方面拔牙后立即植入种植体时美学效果可能更好。没有足够可靠的证据支持或反驳在新鲜拔牙窝中即刻植入种植体时进行骨增量程序的必要性，也没有证据表明任何一种骨增量技术优于其他技术。
