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Multifactorial Analysis of Implant Removal - A Retrospective Study of 19 year data

  • Author(s): Petrovska, Anastasiya
  • Advisor(s): Kapila, Yvonne
  • et al.

Introduction: Dental implants have become a popular choice for replacing missing teeth. It is estimated that every year, over two million implants are placed throughout the world. However, dental implants may exhibit immediate or delayed complications that could lead to implant failure. The aim of this study was to explore the factors coincidental with removal of failed implants at the UCSF Postgraduate Periodontology Clinic (PGPC) by reviewing electronic health records (EHR) for the last 19 years.

Methods: EHR data from Axium were searched for the dental code D6100 (implant removal) from January 2001 – April 2019. Furthermore, code D7140 (simple tooth removal) was used to include cases that were suspected to be misclassified. Inclusion criteria was focused on patients who had dental implant(s) removed and had sufficient records for analysis. Patient and surgical data were gathered from dental records and analyzed. Exclusion criteria focused on patient data that was incomplete or not accessible.

Results: Upon review of 3,426 simple tooth extractions and 81 implant explantations, it was determined that 114 implants were explanted from 88 patients over 19 years. Fifteen patients were removed from the data analysis based on exclusion criteria. Analysis was performed on 73 patients who had a total of 96 implants removed. Of these, 59% of patients had periodontal disease and 32% were smokers. Amongst the medical conditions reviewed, 32% of patients reported cardiovascular disease, 23% had a bone disorder, and 18% had emotional disorders. In terms of the implants, 41 implants were placed in grafted bone; 54% being allograft. Out of 96 implants removed, 58 were late failures and 33 implants failed before loading. Furthermore, we examined the reasons for tooth extractions at sites with subsequent implant failure and found that 6 teeth had endodontic treatment and 3/6 had periapical abscesses. Forty-five percent of cases that had a late failure did not report regular recall and maintenance appointments.

Conclusion: Implant failure was coincidental with a history of periodontal disease and other risk factors, such as cardiovascular disease and emotional disorders. A lack of consistent maintenance recalls was frequently found in cases with late implant failure. Not every patient is a good candidate for implant therapy and risk factors have to be carefully evaluated and presented to the patient. This research highlights the need for a systematic evaluation of patients planning to receive implants and the need to inform them of possible complications and risks of implant treatment.

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