Journal of AdvancedMedical and Dental Sciences Research

Botulinum toxin (BTX) has a number of cosmetic, medical and dental applications. One of the dental applications of BTX is treatment of excessive salivation. Local BTX injection into salivary glands has an effect on the histology, and integrity of the tissues. Myosins are contractile proteins that are highly expressed in myoepithelial cells (MECs) and present around salivary gland ducts and acini to help maintain normal salivary flow. The aim of this study is to investigate the effect of BTX injections on the submandibular salivary glands of adult female Albino rats, when administered solely or in conjunction with Epidermal growth factor (EGF) through immunohistochemical localization of myosin in the parenchyma of the gland. Sixty rats were used in this study and were equally divided into control (saline) group, BTX group and EGF + BTX group (Combined treatment). The results obtained from this study showed that myosin expression in submandibular salivary glands of rats significantly decreased after a single subcutaneous injection of 2.5 units of BTX in 0.1ml saline. However, daily intraperitoneal injections of EGF with a dose of 10 µg/Kg body weight restored normal levels of myosin expression, as well as normal integrity and function of submandibular salivary glands. Further confirmation of the above findings is recommended through immunohistochemical localization of E-cadherin as well as ultrastructural examination of submandibular salivary glands treated with BTX and EGF. 
Key words: Submandibular salivary gland, Epidermal growth factor, Botulinum toxin, Clostridium, Myosin.