Background

Success and survival rates of endosseous implants are well-documented in a number of controlled clinical trials and systematic reviews [1,2,3]. Generally, controlled trials evaluate endosseous implants in specific clinical situations; thus, the patient population is subjected to rigorous inclusion criteria and follow-up. Accordingly, controlled clinical trials do not reflect the real-life situation in private practice. Numerous factors including experienced clinicians, specialized clinics, restricted inclusion and exclusion criteria, specific indications, and increased time spent during follow-up, may affect or even bias the results, outcomes, or reported implant success and survival rates [4]. Consequently, there is an increasing trend in assimilating and reporting real-life data [4] allowing for the evaluation and assessment of dental implants in daily practice. An observational, non-interventional study in a non-homogeneous population better reflects daily practice than a controlled clinical study.

Various studies have reported on success and survival of endosseous implants in private practice settings. In a 5-year prospective observational study on 590 patients, Cochran et al. [5] evaluated 990 implants placed under routine private practice conditions. Very high cumulative survival and success rates were achieved after 3 years (> 99%) and 5 years (97%) of loading. These results were found to be comparable with the rates of survival and success of the same sand-blasted, large grit, acid-etched (SLA) implants achieved in a controlled, prospective, multicenter clinical study (Cochran et al. 2002 as cited in [5]).

Nevertheless, observational studies performed in private practice are not without their flaws; studies have shown that patients may be poorly motivated to attend follow-up appointments [6, 7], and results from various studies imply that, in non-controlled clinical settings, follow-up attendance may drop when patient satisfaction is high [6,7,8]. In contrast, regular follow-up appointment attendance is integral to the study design in controlled clinical trials; therefore, the patient’s obligated attendance to follow-up appointments may mask their natural behavior when satisfied.