Implant failures and age at the time of surgery: A retrospective study on implant treatment in 2915 partially edentulous jaws

Abstract

Purpose: To further report and analyze data on the prevalence of implant failures related to age at surgery in partially edentulous jaws.Materials and Methods: Altogether, 2915 partially edentulous jaws (Kennedy Class I and II) were consecutively treated with 9167 implants over a 30-year period (1986-2015) in one referral clinic. All implant failures were consecutively recorded and the first event of implant failure was analyzed in relation to patient age at implant surgery.Results: A total of 2453 patients participated in the study. The main observations were a nonlinear, normal distribution association between risk of implant failure and age at surgery with the highest risk in middle-aged patients. The risk for implant failures was significantly higher for middle-aged patients (45-64 years) than for old patients at the time of surgery (P < .05). The overall cumulative survival rates for treated jaws increased consistently from the age group of 40 to 49 years to that of >79 years. However, younger age groups (<40 years) presented a different pattern.Partially edentulous patients included late in the study (2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015) presented a more pronounced nonlinear, normal distribution, and the highest risk of implant failure in patients between 50 and 55 years of age at surgery.Conclusions: An overall nonlinear risk pattern of implant failure was observed, with the highest risk in the middle-aged group at implant surgery. Overall cumulative survival rates were highest in the youngest and oldest age groups at implant surgery, and this pattern became more pronounced in patients included late in the study.

Data on implant failures will show different results depending on how patients are compiled and analyzed: A retrospective study on 3902 individual patients treated either with one single implant or implants in the edentulous upper jaw

“…This pattern was observed in the present univariable analysis (Table ; total group) and is consistent with implant‐level results reported by others in mixed populations using comparable analytical approaches . However, when patients were analyzed strictly according to clinical conditions in multivariable analyses also including nonlinear statistical methods, another pattern was revealed . Partially edentulous patients (Kennedy Class I and II) were recently reported to present a higher risk of implant failures when aged 45‐55 years, with a lower risk observed in younger and older age groups .…”

“…Furthermore, a significant association between the risk of implant failure and age at surgery is not observed in the present young single implant group, but a significantly higher risk is associated with an older age when young patients treated with a single implant are here pooled with older, high‐risk edentulous patients (Tables ). However, a significantly decreased risk of implant failures with increasing age was observed when only edentulous patients were included in the analysis (Tables 3‐5), in accordance with previous studies . This finding further exemplifies the importance of detailed presentations and considerations of patient distributions in a study, as suggested by STROBE…”

“…When the groups are pooled into one group, it can also be observed that patients with the most common condition in the total group may have greater impact on the result (Table ; “implant level”). Similar observations with different risk patterns in patients with different clinical conditions have been observed earlier . Also, different distribution of the use of one‐ vs two‐stage surgery and use of nonautologous bone grafts in different clinics have been reported to be associated with different risk of implant failures .…”

“…35,36 Partially edentulous patients (Kennedy Class I and II) were recently reported to present a higher risk of implant failures when aged 45-55 years, with a lower risk observed in younger and older age groups. 35 Since edentulous patients are rarely aged less than 40 years at the time of implant surgery, very few very young edentulous patients were included in these populations. 35,36 Thus, a significant linear decrease in the risk of implant failure was observed for middle-aged to elderly edentulous patients.…”

“…35 Since edentulous patients are rarely aged less than 40 years at the time of implant surgery, very few very young edentulous patients were included in these populations. 35,36 Thus, a significant linear decrease in the risk of implant failure was observed for middle-aged to elderly edentulous patients. 35,36 Furthermore, a significant association between the risk of implant failure and age at surgery is not observed in the present young single implant group, but a significantly higher risk is associated with an older age when young patients treated with a single implant are here pooled with older, high-risk edentulous patients (Tables 3-5).…”