A comprehensive and critical review of dental implant placement in diabetic animals and patients

Objectives: A thorough and exhaustive analysis of the available studies concerning placement of endosseous dental implants in diabetic subjects has not been previously published. The aim of the present study was to perform a comprehensive and critical review of experimental and clinical studies published in the international peer-reviewed literature in the English language regarding endosseous implant installation in diabetic subjects and to draw evidence-based conclusions on the effectiveness and predictability of dental implant therapy in diabetic patients. Materials and methods: Literature search for articles published up to and including March 2005 in the English language was performed with a personal computer (PC) using The National Library Of Medicine (http://www.ncbi.nlm.nih.gov/PubMed) and Cochrane Oral Health Group databases. Search strategy included a specific series of terms and key words. The reference lists of identified publications, relevant texts and previous workshops were also scanned. Data sources also included several hand-searched journals and contact with experts, when it was considered appropriate. Search was conducted independently by the three reviewers (S. K., I. K. K., I. F.). At the first phase of selection the titles and abstracts and at the second phase full papers were screened independently by the three reviewers. Disagreement regarding inclusion of full papers was resolved by discussion among the reviewers. Results: The search provided 227 potentially relevant titles and abstracts. At the first phase of evaluation, 199 publications were rejected based on title and abstract. At the second phase, the full text of the remaining 28 publications was retrieved for more detailed evaluation. These publications included 11 experimental studies and 16 clinical studies (one clinical study corresponded to two publications). Finally, 11 experimental and eight clinical studies were accepted. Clinical studies included four prospective and four retrospective studies. Because of the limited number of available studies and their heterogeneity, focusing on a specific predefined question to be answered by a systematic review was not feasible and therefore no meta-analysis was planned. Conclusions: Within the limits of the existing investigations, experimental studies seem to reveal an impaired bone healing response to implant placement in diabetic animals compared with non-diabetic controls, both quantitatively and qualitatively. The majority of clinical studies tend to indicate that diabetes is no contraindication for implant placement, on condition that it remains under metabolic control. However, definitive guidelines with objective criteria, such as type and duration of diabetes and glucosylated hemoglobin levels, need to be established in the future.