CAUSES
Early Implant Failure (before osseointegration)
Occurs within the first weeks to months after placement, often due to:
Poor Bone Quality or Quantity
- Inadequate bone volume for stability
- Low bone density (e.g., in the posterior maxilla).
Surgical Trauma
- Overheating the bone during drilling
- Excessive compression of cortical bone
Contamination or Infection
- Bacterial contamination at time of placement
- Poor aseptic technique
Micromovement of the Implant
- Lack of primary stability
- Premature loading or patient non-compliance
Systemic Health Issues
- Uncontrolled diabetes
- Smoking
- Immunosuppression or chemotherapy
Medication-Related Complications
- Bisphosphonates
- SSRIs or PPIs (possible effects on bone healing)
Late Implant Failure (after osseointegration)
Occurs months to years later, often due to:
Peri-Implant Mucositis
- Inflammation of soft tissues around the implant.
- Usually reversible with good oral hygiene
Peri-Implantitis
- Progressive bone loss with inflammation
- Caused by plaque accumulation and pathogenic biofilm
- May be accelerated by poor prosthetic design or cement remnants
Excessive Occlusal Forces / Bruxism
- Overloading of the implant
- Lack of occlusal adjustment or protective appliances
Poor Prosthetic Planning or Execution
- Misaligned implants
- Ill-fitting abutments or restorations
- Cement left in peri-implant sulcus (if not screw-retained)
Inadequate Maintenance
- Lack of patient compliance with hygiene and recalls
- No regular professional cleaning or monitoring
Mechanical Failures
- Fractured implant, screw, or abutment
- Loosening of components
Iatrogenic Causes
These are failures resulting from the clinician’s technique or decision-making:
