Materials and methods

Focused question

1. Does length of the wide-diameter implant influence its survival?
2. Does the surface modification influence its survival compared to machined implant surfaces?
3. Does the implant placement in the maxilla or the mandible influence its survival?

Literature search and study design

The database on PubMed, Web of Science, and Cochrane Central Register of Controlled Trials was searched from inception to December 15, 2014. The keywords for the search were “dental implants or dental implant” and “wide,” and a reference librarian was consulted as to the most effective strategy. Gray literature was also searched on Google Scholar using advance search to find articles with all of the words “wide, dental, implants, endosseous, clinical, patients, survival” and without the words “animal, graft, augmentation, immediate, review”. Hand searching was conducted on the reference lists of identified wide-diameter implant articles and was limited to articles not already identified in the above search strategy. Implant representatives of implant manufacturers were also contacted for any ongoing research pertaining to wide-diameter implants, and researchers were invited to clarify research information.

Inclusion/exclusion criteria

1. Randomized controlled trials, controlled clinical trials, cohort, and case series reporting on the implant survival of wide-diameter endosseous titanium implants with different surface modifications were included. Only prospective data were included. Case reports, conventional reviews, and systemic reviews were excluded.
2. Implant diameter greater or equal to 4.7 mm were considered wide-diameter implants.
3. Only articles with specific documentation for wide-diameter implants were included. This documentation includes implant length, location/site, loading times, and specific failure data such as length, location, and timing of failure for wide-diameter implants.
4. Articles with information on implants placed in sites deemed to have adequate bone height and width, and did not require site development, were included. Articles with grafted sites and/or unclear description of how sites were selected were excluded.
5. Only articles with data on wide implants loaded after least 1–3 months of healing after implant placement were included; data on immediate placement in extraction sites and immediately loading implants were not covered in this review.
6. Wide-diameter implants used in immediate replacement of failed implants were excluded.
7. Studies with at least 1-year follow-up and included at least 10 implants regardless of diameter and length were included.
8. Patients with adequate health to undergo implant surgery and patients with controlled medical conditions were not excluded.
9. Smoking status of subjects was not considered a criterion for exclusion.
10. Non-English articles or articles without English translations were excluded due to language limitations.