Design, formulation, and physicochemical evaluation of periodontal propolis mucoadhesive gel

Abstract

Background: Periodontitis is a disease of tooth supporting tissues, and Gram-negative Bacteria are
the main cause of this. Propolis has antibacterial, anti-infl ammatory, and antioxidant effects due to its
high polyphenol and fl avonoids content. The aim of this study is the formulation of a mucoadhesive
gel containing concentrated extract of propolis for treatment of periodontitis.
Materials and Methods: Formulations containing carbopol 940, sodium
carboxymethylcellulose (NaCMC), hydroxypropyl methylcellulose K4M, and propolis extract were
prepared. Among ten prepared formulations, fi ve formulations had acceptable and proper physical
appearance and uniformity; thus, they were selected for physicochemical tests (centrifugal, thermal
change, cooling and heating, freeze and thaw, thermal stress, and pH evaluation), quantifi cation
of fl avonoids, viscosity, mucoadhesion, drug release, and syringeability tests. We investigated the
antibacterial activity of F10 (carbopol 940 1%, NaCMC 3%) against Porphyromonas gingivalis using
the disk diffusion method.
Results: Phenolic content was measured 39.02 ± 3.24 mg/g of concentrated extract as gallic acid
and fl avonoid content was determined 743.28 ± 12.1 mg/g of concentrated extract as quercetin.
Highest viscosity (3700 cps) and mucoadhesion (21 MPa) were seen in F10. Study of release profi le
in F10 also revealed that propolis could release from this system in more than 7 days. All of the
fi ve selected formulations had ease of syringeability in 21-gauge needle for drug delivery into
periodontal pocket. In the disk diffusion method, F10 produced signifi cant growth inhibition zones
against P. gingivalis.
Conclusion: Controlled release of drug into periodontal pocket helps effective treatment
and recovery, higher persistence and reduces drug use frequency. Increase of carbopol 940
leads to viscosity and mucoadhesion elevation and accordingly decreases of release rate. F10
was the best formulation because of highest viscosity and mucoadhesion and lowest release
rate. It had efficient function in treatment of periodontitis, so we recommend it for clinical
evaluation.
Key Words:Antibacterial, effects, fl avonoids, compounds, oral, drug delivery systems,
periodontitis, propolis