certain conditions that increase the risk of implant failure are poorly controlled diabetes, some bone metabolic and congenital disorders, certain medications like glucocorticoids, immunosupressants and bisphosphonate medications. Additionally, smoking and poor hygienic habits can lead to an increased risk of implant failure. People with these disorders and/or on these medications should bring those to the attention of their implant surgeon so a treatment plan can be tailored to fit their needs and their medical conditions.
There are other factors that can lead to an increase in dental implant failure. Implants can fail early on in the healing phase or late. Early failures would be defined as any time before osseointegration occurs (healing phase) or at the time the crown is affixed to the implant. Late failure is defined as any time after the implant with the tooth is under function.
Factors that can cause early failure are:
This type of failure occurs shortly after the implants are placed. They can be caused by:
- overheating the bone at the time of surgery (usually due to lack of good irrigation)
- too much force when they are placed (too tight fitting implants can actually cause bone to resorb)
- not enough force when they are placed (too loose fitting implants don't stay immobile and don't heal properly)
- contaminated implant
- infection
- contaminated osteotomy
- epithelial cells in osteotomy site (connective tissue or scar tissue fills the socket around the implant instead of bone)
- poor quality of bone
- excessive forces during osseointegration (during healing the implant is under function, is mobile and therefore bone doesn't affix to the implants)
- poor compliance with post operative medication and/or instructions
- other rare reasons like implant rejection from a titanium alloy allergy.
Late failures typically include poor hygiene from the patient. Patients' often lose teeth because of poor care and the habit continues for some despite the implant surgery. Sometimes the implant is simply overloaded. Some patients have higher bite forces and may have needed more implants to distribute the forces more harmoniously. Lateral forces can cause implants to fail late. Implants, as well as teeth, like to be loaded straight up and down. When teeth and especially implants are loaded tangentially or laterally, they weaken the bone around themselves and begin to fail. There are lots of other reasons implants can fail. Some are controllable and avoidable and some are not. So how can a patient best insure their odds and minimize their risk of implant failure? The biggest help patients can do is stay compliant with the medications and instructions before and after the procedure.
TEETH Care Centre Dental Hospital, Ahmedabad
