This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
[{'content': 'Which of the following is the most common cause of overdenture abutment failure? \nSelect and explain. \nA. Caries, B. Periodontal complications, C. Endodontic complications, D. None of the above', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Most frequent cause of overdenture abutment failure is periodontal complication (70%) followed by\xa0caries (25%) and endodontic complications (5%).', 'role': 'assistant'}]