Short-term to early mid-term survival rates of progressive thread dental implants - a retrospective study of 9617 implants in 4253 patients

Since decades, dental implants have been used with great success for oral rehabilitation after tooth loss. Although abundant literature has been published in this field, there is still need for studies evaluating high numbers of dental implants placed in large patient collectives. Herein, we present the analysis of an extensive database including the assessment of potentially influencing factors on implant survival rates. In this retrospective study, patient data from 03/2016 to 10/2024 were collected and analyzed. Collected data included sex, age, date of surgery, date of implant loss, location, number, core design, length, and diameter of implants, open versus flapless (punch) surgery, smoking, osteoporosis, and diabetes. Cox proportional hazard models were used to evaluate these factors with regard to their potential influence on implant survival rates. Implant diameter was modeled using restricted cubic splines. A sensitivity analysis was done to further investigate the non-proportional effect of punch. 9617 dental implants placed in 4253 patients (2444 women and 1809 men) could be included. The mean follow-up was 2.01 years. The cumulative survival rate was 0.990 after 1 year, 0.981 after 3 years, 0.969 after 5 years, and 0.936 after 7 years. Multivariable analyses revealed the following associated factors: core design (for early loss), implant diameter (non-linear association with higher failure rate), male sex (slightly lower rate of implant loss). Our observational study showed high survival rates of progressive thread dental implants comparable to results reported in international literature. Survival rates were significantly influenced by implant design, implant diameter, and male sex. Implant length, number of implants, jaw region, surgical approach, osteoporosis, diabetes, and smoking, did not show a significant influence on implant survival.