种植体即刻负重或早期负重与延期负重相比对种植体成功率影响的Meta分析

Implant Success Ratio between Implant Immediate Loading/Early Loading and Delayed Loading: A Meta-analysis

目的系统评价种植体即刻负重或早期负重与延期负重相比对种植体成功率的影响。方法计算机检索PubMed、EMbase、CNKI等数据库，收集1997-2007年间国内外所有有关种植体即刻负重或早期负重与延期负重对比的随机对照试验或前瞻性病例对照研究。对纳入研究进行质量评价、数据提取，并进行Meta分析。结果共检索到16篇符合纳入与排除标准的文献，剔除两篇重复报道后，纳入14个研究进行Meta分析，其中5篇为随机对照试验。Meta分析结果显示，与延期负重相比，早期负重种植体失败率略低，但差异无统计学意义[OR=0.54，95％CI（0.22，1.33），P=0.18]；纳入所有病例对照研究再分析以及进行敏感性分析，结果也是如此。与延期负重相比，即刻负重种植体总失败率更大，但差异无统计学意义[OR=1.51，95％CI（0.53，4.25），P=0.44]；分析随机对照试验时虽有即刻负重更有利于种植体成功的趋势，但差异亦无统计学意义；进行敏感性分析时除剔除Jo等的文献后结果不一样外，其余结果均显示即刻负重与延期负重对种植体成功率的影响无统计学差异。结论现有的有限证据表明，当骨质较好（至少为Ⅲ级骨）时，早期负重比延期负重有更有利于种植体成功的趋势；而即刻负重和延期负重相比，种植体成功率差异无统计学意义。受纳入文献数量和质量的限制，本次Meta分析结果尚有待于高质量的大样本随机对照试验以予证实。

Objective To use a meta-analytic technique to estimate the survival of implants between immediate loading/early loading and delayed loading. Methods We carried out a systematic search of electronic databases for all prospective trials comparing conventional delayed implant loading with early or immediate implant loading, reported between 1997 and 2007. The outcome of interest was implant failure rate. Quality assessment was performed for prospective trials that met the eligibility criteria and the data were then extracted and analyzed. Results Sixteen articles were found to meet the eligibility criteria, but two studies were reported in four articles, so that 14 artides were analyzed. There were five randomized controlled trials （RCTs）. Compared to delayed loading, implant failure occurred slightly, but not statistically significant, less often with early implant loading （OR=0.54, 95%CI 0.22 to 1.33, P=0.18）. We combined all cohort studies and this analysis was consistent with this result. Immediate implant loading was associated with slightly, but not statistically significant, worse outcomes （OR=l.51, 95%CI 0.53 to 4.25, P=0.44）. We only pooled the RCTs and results showed better implant success rate with immediate implant loading, but with no significant difference. When sensitivity analyses were performed by the sequential dropping of a single study, no significant differences were observed except when the study of Jo et al was excluded. Conclusion Early implant loading was associated with better outcomes compared to delayed loading when the implants were placed into good quality bone. There was no significant difference of the implant success rate between immediate loading and delayed loading. Further evaluations in adequately powered large RCTs are needed to confirm these findings.