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Associated Topics

Insufficient evidence for timing placement after tooth extraction and need for bone augmentation

Hoda Abdellatif BDS, MPH, DrPH .


Systematic Review Conclusion

There is insufficient evidence that timing and bone augmentation associated with implants impact differential success, complications, aesthetics, and patient satisfaction outcomes.

Critical Summary Assessment

This high quality review, which considered only randomized controlled trials, provided insufficient evidence for determining both the advantages or disadvantages of various implant treatment times or the need for bone augmentation at the implant site.

Evidence Quality Rating

Limited Evidence

Structured Abstract

Clinical Questions:

In patients who need implant placement, 1) Which procedure (immediate (I), immediate-delayed (ID) or delayed (D) implant) is most effective in terms of success, complications, aesthetics and patient satisfaction; and 2. Are bone augmentation procedures beneficial with respect to the primary outcomes?

Review Methods:

The authors conducted a comprehensive literature search of four databases and hand searched relevant journals through June 2010, with no language restrictions. They also attempted to include unpublished research. They implemented a clear protocol. Two independent reviewers identified studies, assessed methodological quality and extracted data. The authors considered studies for inclusion if they were RCTs with at least a one year follow-up period in function comparing I, ID and D implants, or comparing various bone augmentation procedures around the inserted implants. Outcomes included patient- and clinical-oriented measures. Meta-analysis was performed using fixed- and random-effect models.

Main Results:

This systematic review identified 14 eligible RCTs. Seven were judged to be of poor quality with regard to study design and/or data issues. The remaining seven were included with a total of 270 patients. No statistical differences were found in the two RCTs that compared I versus D implants in 126 patients. In one trial (46 patients) that compared ID versus D, two years after implant patients in the ID group perceived the time to functional loading as significantly shorter, were more satisfied, and the level of peri-implant marginal mucosa was more appropriate. These differences disappeared five years after loading, and significantly more complications occurred in the ID group (risk ratio [RR] = 4.20; 95 percent confident interval [CI], 1.01 to 17.43). No statistical differences were found in the one RCT that compared I with ID implants in 16 patients. In three RCTs that evaluated different techniques of bone grafting for implants immediately placed in extraction sockets, no statistically significant differences were observed.


Trials investigating timing and bone augmentation for implants are few and underpowered. They do not provide reliable evidence that allow conclusions to be made about their merits. Compared with D implants, both I and ID implants appear to have higher risks of implant failure and complications but may have better aesthetic outcomes when placed immediately after tooth extraction. There is not enough evidence to support or refute bone augmentation.

Source of Funding:

The University of Manchester.


Importance and Context:

Dental implant for replacing missing teeth is a well-established treatment option. The different approaches to place dental implants after tooth extraction include I, ID and D implants. This review compared these implant placement types, as well as examined whether bone augmentation improved prosthesis/implant success while reducing complications.

Strengths and Weaknesses of the Systematic Review:

The research question and well-defined eligibility criteria were established a priori. The authors conducted a comprehensive search of quality sources and screened for appropriate relevance. Two independent reviewers extracted data. The authors attempted to include unpublished research, and this resulted in no additional studies. Risk of bias for each study was assessed; most of the studies had high risk of bias. Results were expressed using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95 percent confidence intervals. Results were combined using fixed-effect models. Tests for homogeneity were not used to decide between fixed- and random-effects modeling. Publication bias was not assessed.

Strengths and Weaknesses of the Evidence:

All included studies were RCTs and parallel group designs of consistently defined interventions (I, ID, and D). Outcomes from the studies were comprehensive, including both patient- and clinical-oriented measures. Quality of each study varied. Five were without power analyses and all but one had high risk of bias. Findings were consistent across the included studies. The number of studies and sample sizes were small. Conflict of interest was acknowledged in four of the included trials.

Implications for Dental Practice:

The review fails to provide sufficient evidence for determining the optimal time for placing dental implants after tooth extraction and the need for bone augmentation procedures. It did not substantiate any benefits associated with I or ID implants. The patient should assume an important role in the treatment decision-making process. Factors such as aesthetics, cost, time, and side-effects may be considered.

Critical Summary Publication Date:


These summaries are not intended to, and do not, express, imply, or summarize standards of care, but rather provide a concise reference for dentists to aid in understanding and applying evidence from the referenced systematic review in making clinically sound decisions as guided by their clinical judgment and by patient needs. American Dental Association © 2019