The risk factors of early implant failure: A retrospective study of 6113 implants

Background The risk factors of early implant failure were controversial among previous studies, especially for implants in different sites. Purpose To analyze the rate and risk factors of early implant failure occurring before the placement of final prosthesis. Materials and methods A retrospective study was conducted based on electrical medical records of patients who received dental implant placement from 2015 to 2019. Generalized estimation equation analyses were used to explore potential risk factors influencing early implant failure. Results Overall, 6113 implants in 3785 patients were included. The rate of early implant failure was 1.6% at patient level and 1.2% at implant level. The early implant failure was significantly associated with implants in the posterior maxilla, with specific surface modifications and in previously augmented sites (p < 0.05). Risk factors for maxillary implants included surface modification and bone augmentation procedures (p < 0.01), whereas risk factors for mandibular implants included gender and bone augmentation procedures (p < 0.05). For implants placed in previously augmented sites, implants placed in the anterior mandible had a higher risk of early failure (p < 0.05). Conclusions The risk factors for early implant failures varied among different sites; hence, they should be comprehensively considered in presurgical treatment plan.