Secreting saliva is the main function of salivary glands, and salivary function’s declining is a common feature because of a variety of salivary gland diseases, especially the obstructions. This review will focus on common reasons that can lead to the functional changes in the salivary glands, and evaluate the functions of the salivary glands. Thus, it can provide objective standards for the evaluation of clinical therapy of salivary gland disease.
