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WITHDRAWN: Interventions for replacing missing teeth: surgical techniques for placing dental implants.

BACKGROUND
Many variations in the surgical technique for the placement of dental implants have been developed since the introduction of implant surgery into clinical practice. These include variations in the timing of implant placement in relation to the tooth removal, and variations in the way the recipient bone site is prepared, amongst others.


OBJECTIVES
To test the null hypothesis of no difference in the success, function, morbidity, patient satisfaction and cost-effectiveness of different surgical techniques for placing dental implants, against the alternative hypothesis of a difference.


SEARCH STRATEGY
The Cochrane Oral Health Group Trials Register, the Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE were searched. In addition, the bibliographies of review articles were checked for studies outside the handsearched journals and personal references were searched. 55 implant companies were also contacted.


SELECTION CRITERIA
Randomised controlled clinical trials (RCTs) of implant surgical techniques.


DATA COLLECTION AND ANALYSIS
Authors were contacted for details of randomisation and data and quality assessment was carried out (ME, PC). Data were independently extracted, in duplicate, by two reviewers (HW, PC). The Cochrane Oral Health Group's statistical guidelines were followed.


MAIN RESULTS
Four RCTs (six publications) were suitable for inclusion in this review of the nine RCTs (11 publications) identified. Two different aspects of implant surgical technique were reported in these RCTs. These were, two versus four implants to support a mandibular overdenture and crestal versus vestibular incision for implant placement. At the patient level there were no statistically significant differences for any of these alternative techniques with respect to implant failures, marginal bone levels, morbidity or patient satisfaction.


AUTHORS' CONCLUSIONS
This review included studies evaluating the surgical techniques of two versus four implants to support a mandibular overdenture and crestal versus vestibular incision for implant placement. Based on the available results of RCTs, there is no strong evidence supporting superior success with one or other of the alternative techniques for either of these two aspects of surgical technique. These conclusions are based on a few RCTs for each aspect of surgical technique and some with relatively short follow-up periods and few patients.