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
Immediate implant placement in extraction socket can be indicated in? 
Select and explain. 
A. Periodontal bone loss, B. Suppuration, C. Cellulitis, D. Lack of bone apical to socket
A: Periodontal bone loss
Answer: A: Periodontal bone loss 
Explanation: Indications and contraindications of immediate implant placement in extraction socket according to Block & Kent:-