This review assessed the effects on outcomes of time-to-loading for a fixed or removable prosthesis placed on dental implants. The authors found no differences between immediate or early and conventional loading, but the uncertain impact of variability between studies means that the authors’ conclusions should be treated with caution.

To assess the effects on outcomes of time-to-loading for a fixed or removable prosthesis placed on dental implants.

MEDLINE was searched to May 2005 for English-language studies. The authors checked references from retrieved articles and a personal database for additional studies. Search terms were not reported.

Studies that compared early or immediate loading of implants with a delayed procedure were eligible for inclusion. Included studies comprised randomised controlled trials (RCTs), prospective controlled trials and retrospective studies containing more than five patients. Cross-sectional studies and retrospective studies that contained fewer than five patients were excluded. Only studies designed to include a comparison or control group were included. Implant systems varied, the most commonly reported were Brånemark, ITI and 3i. Outcomes included failure based on various criteria, mechanical complications, pain and bone levels with various criteria used. The study observation period was between one and 10 years. Two reviewers independently selected the studies for inclusion in the review.

The authors did not state that they formally assessed validity, but the methodological quality of the RCTs was reported based on the adequacy of description of treatment allocation and allocation concealment. The criteria used for this process were not reported.

Outcomes for trial interventions were extracted.

Data were extracted independently by two reviewers.

The pooled risk differences and confidence intervals (CIs) for implant failure at various time points were calculated using the DerSimonian and Laird random-effects model. Publication bias was assessed using a funnel plot.

A total of 22 studies (n=781, range 7 to 195 patients) were included in the review, seven of which were RCTs, 13 were prospective trials with a concurrent control group and two were retrospective with a concurrent control group. The methodological quality of the RCTs ranged from poor to good.

No significant difference was detected between immediate or early loaded implants compared with implants using a conventional loading method. No evidence of publication bias was found.

There were no differences in outcomes between implants loaded early and immediately and those loaded with a conventional healing period.

The review addressed a clear question and undertook an adequate search for studies with clear exclusion criteria. Inclusion criteria for study designs were broad, so the review was not limited to the best evidence to answer the study question. The literature search was restricted to publications in English and there was no apparent search for unpublished studies, therefore, some studies may have been missed. It was unclear whether the language restriction was part of the inclusion criteria or not. Both publication and language bias could have been present, but publication bias was assessed formally and none was detected. Appropriate methods were used to minimise reviewer error and bias during the review process, which was conducted in duplicate. The methodological quality of the RCTs ranged from poor to good, although the process used to derive these values was unclear. Most studies were small and varied with respect to outcomes and follow-up, although no formal assessment of heterogeneity was undertaken. In light of the uncertainty underlying study quality and the variability present between studies, the authors’ conclusions should be treated with caution.

Practice: The authors stated that the immediate/early loading of implants placed in the interforaminal area can be considered a reasonable treatment to delayed loading, but the applicability of such protocols should be considered in the context of the unique anatomic, biomechanical and host factors as well as clinician competency.

Research: The authors stated that further verification was necessary to evaluate implants for other intraoral locations. Priority should be given to research on implant surface characteristics, partial edentulism and the maxillary arch. Other factors worthy of investigation included host factors, environmental factors, number of implants, implant geometry, types of prostheses, local factors, stability of outcome assessments, treatment efficiency and patient satisfaction.

Not stated.

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.