The ultimate goal of periodontal therapy includes the arrest of progressive periodontal disease and reformation of those parts of the periodontium that were destroyed by the disease. Another goal of therapy is predictable regeneration of the periodontium at the site of previous breakdown. The regeneration is defined as 'reproduction or reconstitution of a lost or injured part so that the form and functions of the lost structures are restored' . The periodontal regeneration is defined as regeneration of the tooth's supporting structures including alveolar bone, periodontal ligament and...