Prospective and retrospective studies that evaluated outcomes for conventional root-form endosseous implants in patients whose periodontal condition was clearly described were eligible for inclusion. Studies had to follow-up at least 80 per cent of patients for at least one year (under loading). Case reports were only included if they involved eight or more patients (or 10 or more implants). Studies could compare outcomes for patients with and without a history of periodontitis or only report on patients with periodontitis.
The primary review outcomes were early implant loss (lost or removed before prosthetic reconstruction) and late implant loss (lost or removed after reconstruction). Other outcomes were fractured implants, marginal bone loss (based on radiographic examination), attachment level/probing depth, bleeding upon probing and peri-implantitis.
Most studies were in partially edentulous patients. Where reported the age of patients ranged from 21 to 86 years. The duration of follow-up ranged from one to 168 months.
Two reviewers independently selected studies.