An Overview of Characteristics of Registered Studies on Dental Implants

•ClinicalTrials.gov registry was created with the intention of increasing the transparency of conducted or ongoing clinical studies and to minimize publication bias commonly seen with industry-sponsored studies.•As of the study conduct date (01/01/2014), a total of 205 studies on dental implants were registered.•Results of the current study showed that a predominating number of registered studies are funded by industry and other sources.•Very few registered studies have made their results public, and the ClinicalTrials.gov registry does not provide sufficient information on the quality of study design and thus precluding the public and researchers to judge on the quality of registered studies and publication bias.

ObjectiveClinical trials serve as the empirical basis for clinical decision making. The objective of the current study is to provide an overview of clinical trials examining dental implant outcomes.MethodAll registered studies on Dental Implants were selected for analysis. The clinicaltrials.gov website was used to query the characteristics of registered studies. The search term used was dental implants.ResultsAs of the study conduct date (01/01/2014), a total of 205 studies on dental implants were registered. These included 168 interventional and 37 observational studies. Results were available for only 14 studies. All observational studies and 98.8% of interventional studies included both male and female subjects. Close to 60% of studies had sample sizes between 1 and 50. NIH was listed as funding source in only 5 interventional studies and 3 observational studies. 80% of interventional studies were randomized. However, double masking was reported in only 15% of interventional studies with majority being open labeled.ConclusionClinicalTrials.gov registry was created with the intention of increasing the transparency of conducted or ongoing clinical studies and to minimize publication bias commonly seen with industry-sponsored studies. Results of the current study showed that a predominating number of registered studies are funded by industry and other sources, very few registered studies have made their results public, and the ClinicalTrials.gov registry does not provide sufficient information on the quality of study design and thus precluding the public and researchers to judge on the quality of registered studies and publication bias.