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
Regeneration in periodontal therapy aims at: 
Select and explain. 
A. Bone refill, B. Repair of the bony defect, C. Reconstitution of the lost periodontium, D. Removal of the diseased bone
C: Reconstitution of the lost periodontium
Answer: C: Reconstitution of the lost periodontium 
Explanation: None