Objectives: The aim of this systematic review was to evaluate the best timing for placing implants after tooth extraction, by comparing early vs. delayed implant placement and evaluating the hard and/or soft tissue ridge dimensional changes and the outcomes related with implant survival and prosthesis success.
Material and methods: An online search of the main databases including The National Library of Medicine (MEDLINE via Pubmed), Embase and The Cochrane Central Register of Controlled Trials was conducted up to February 2011. Randomized controlled clinical trials (RCTs), prospective cohort studies and case-control retrospective studies, with a follow-up of at least 1 month after loading of dental implants, comparing: (i) early vs. delayed implant placement, (ii) augmentation vs. no augmentation at implant placement in early placed implants and/or (iii) the comparison of various augmentation procedures at early implant placement, were conducted. A hand search of relevant journals was also performed. Screening of eligible studies, assessment of their methodological quality and data extraction were conducted in duplicate by two independent reviewers. Authors of studies were contacted for clarification or missing information.
Results: Eight studies were included, although meta-analysis could only be performed with the data from two studies comparing early vs. delayed implant. The percentage of bone height and bone width reduction favoured the early placement, with pooled mean difference between groups of 13.11% (95% CI: from 3.83 to 22.4; P = 0.057) and 19.85% (95% CI: from 13.85 to 25.81) respectively. Implant survival demonstrated a non-significant higher implant survival rate for the early group (RR = 1.02, 95% CI: 0.96-1.1).With regard to patient satisfaction, statistically significant differences between the groups in favour of the early group for overall satisfaction and appearance with the restoration were demonstrated at 2 years, although these differences were lost at 5 years.
Conclusions: Placement of dental implants at an early timing after tooth extraction may offer advantages in terms of soft and hard tissue preservation, when compared with a delayed protocol. Nevertheless, well-designed, high quality, randomized clinical trials, are needed, because the available evidence is today limited in terms of available studies and quality.
© 2011 John Wiley & Sons A/S.