Background: Propolis has been widely used to treat oral cavity disorders, such as endodontal
and periodontal diseases and microbial infections.
Objective: The study aimed at the formulation of commercial Saudi propolis into biodegradable chitosan
chips and evaluation of its effectiveness as a pulpotomy agent.
Methods: The standardization of 80% ethanolic propolis extract was performed regarding its total
phenolic content, total flavonoid content, quantitative estimation of main polyphenolic constituents
and antioxidant activity. Chitosan chips containing propolis extract were prepared by the solvent/
casting method. The investigated variables were % of chitosan polymer (2, 2.5 and 3%), % of plasticizer
(1, 5 and 10%) and incorporation of different concentrations of hydroxypropyl methylcellulose (5,
10 and 20% of polymer weight). The chips were characterized for weight and thickness uniformity, content
uniformity, pH, percentage moisture loss, swelling index, tensile strength and in vitro propolis release.
The optimal propolis chip formulation was further investigated in dogs regarding the short term
response of primary dental pulp to propolis chips compared with the most commonly used formocresol
Results: The prepared films were flexible and demonstrated satisfactory physicochemical characteristics.
The optimal formulation showed an initial release of about 41.7% of the loaded propolis followed
by a sustained release extended up to 7 days. The kinetics study demonstrated that propolis release
was controlled by Fick´s diffusion. The optimal propolis chip formulation resulted in less pulpal inflammation
compared to formocresol, and produced hard tissue formation in all specimens.
Conclusion: Formulation of commercial Saudi propolis as a biodegradable chitosan chip is an effective
alternative to the commercially available chemical agents for the treatment of vital pulpotomy.