 BACKGROUND: Advances in the field of alternative medicine have promoted widespread use of herbal agents, like Aloe vera AV, for both medical and dental therapy. AV has anti-inflammatory, antioxidant, antimicrobial, hypoglycaemic, healing promoting and immune boosting properties. The present study is designed to investigate the effectiveness of AV gel local drug delivery as an adjunct to scaling and root planing SRP in the treatment of subjects with chronic periodontitis CP and type 2 diabetes mellitus DM. 