Brazilian Green Propolis Carried in Lipid-Based Nanostructures: A Potent Adjuvant Therapy to Non-Surgical Periodontal Treatment in the Management of Experimental Periodontitis.

Objective: This study aimed to evaluate the effects of local use of Brazilian Green Propolis (BGP), either as an ethanolic extract (the most common formulation) or incorporated into lipid-based nanostructures, as an adjuvant therapy for non-surgical periodontal treatment in managing experimental periodontitis (EP) in ovariectomized rats. Methods: Fifty-six female Wistar rats underwent bilateral ovariectomies. After 10 weeks, a cotton ligature was placed around the lower first molar and remained in place for two weeks to induce EP. The ligature was removed, and the rats were randomly assigned in the groups NLT (n = 14), SRP (n = 14), SRP-BGPee (n = 14), and SRP-BGPlns (n = 14). In the NLT group, no local treatment was performed. The SRP group received scaling and root planing (SRP), along with irrigation using a physiological saline solution. The SRP-BGPee group underwent SRP and irrigation with ethanolic extract of BGP. The SRP-BGPlns group underwent SRP and irrigation with BGP-loaded lipid nanostructure (BGPlns). Each group received one SRP session followed by four irrigation sessions with the specified solutions, which were conducted immediately after SRP and subsequently after 2, 4, and 6 days. Euthanasia was performed at 7 and 28 days following the removal of the ligatures. The hemimandibles were processed for the following analyses: microtomographic analysis; histological analysis; histometric analysis of the percentage of bone tissue in the furcation region (PBT); and immunohistochemical analysis for tartrate-resistant acid phosphatase activity (TRAP), transforming growth factor beta 1 (TGFβ1), and osteocalcin (OCN). Results: The SRP-BGPlns group demonstrated superior periodontal tissue repair, reduced alveolar bone loss, fewer TRAP-positive cells (at 7 days), and higher levels of immunolabeling for TGFβ1 (at both 7 and 28 days) and OCN (at 28 days) compared to the other experimental groups. Conclusions: The irrigation with BGP is an effective adjuvant therapy for non-surgical periodontal treatment in managing EP in ovariectomized rats. Its application in lipid-based nanostructures proved to be more effective than the ethanolic extract form.