Which of the following is NOT considered a risk factor for implant failure?

Correct answer: C. History of dental caries

• A. Incorrect. A history of periodontitis is one of the strongest predictors of peri-implantitis and implant loss.
• B. Incorrect. Poor plaque control drives peri-implant mucositis and peri-implantitis.
• C. Correct. Caries is a disease of tooth structure. Implants are not susceptible to caries, so a caries history alone does not predict implant failure.
• D. Incorrect. Bruxism creates excessive occlusal overload, a well-documented cause of late implant failure and prosthetic complications.