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 is not a contraindication of apicectomy? \nSelect and explain. \nA. Inadequate periodontal support, B. Horizontal apical root fracture, C. Lesions situated very close to important anatomical structures, D. None', 'role': 'user'}, {'content': 'Answer: B \nExplanation: There are few absolute contraindications for endodontic microsurgery. The following factors play amajor role in the surgical endodontics:\n\nInadequate periodontal support and active uncontrollable periodontal disease.\nPoor restorability with a postendodontic restoration.\nLesions situated very close to important anatomical structures like the inferior alveolar\xa0nerve, lingual nerve, mentaI foramen, maxillary\xa0sinus when there is high risk of damage to\xa0these structures.\nSystemic complications of patients like bleeding disorders, severe heart disease such as a\xa0patient recuperating from a myocardial infarction, and immunocompromised patients.\nPractitioner’s skill and experience with micro-surgical treatment plays an important role.', 'role': 'assistant'}]