Immediate restoration/loading of immediately placed single implants: is it an effective bimodal approach?

OBJECTIVE: To compare systematically the survival and radiographic marginal bone level changes of two immediate implant protocols in the aesthetic region; immediate single implant restoration/loading in extraction sockets (the bimodal approach) compared with the same in healed sites. MATERIAL AND METHODS: A literature search of electronic databases, Cochrane Oral Health Group's Trials Register, National Research Register, conference proceedings and abstracts was performed without language restriction up to 1 August 2008. Hand searching included several dental journals and authors were contacted for missing information. Controlled trials that compared immediate restoration/loading of single implants placed in extraction sites with those placed in healed sites were selected. The meta-analysis was prepared according to the guidelines of the Quality of Reporting of Meta-analyses statement. The data were analysed using RevMan version 5.0 software. A fixed effects model was chosen with standardized mean differences for continuous data, and risk ratios for dichotomous data with 95% confidence intervals. RESULTS: Ten studies with 629 implants were included. Immediate single implant restoration/loading in extraction sockets in the aesthetic zone was associated with significantly higher risk of implant failure (risk ratio of 3.62, 95% confidence interval 1.15-11.45, P=0.03). However, the bimodal approach showed favourable marginal bone changes after 1 year. CONCLUSION: The review and meta-analysis supported the potential advantages offered by this bimodal approach, but indicated a higher risk when compared with immediate restoration/loading in healed ridges. Further long-term, well-conducted, randomized-controlled studies are needed to confirm the validity of this treatment option.