Outcome measurement
primary tastes
A standardized and validated test was used to evaluate the gustatory function. The test aimed to investigate patients’ ability to perceive four primary tastes (sweet, salty, sour, and bitter) [The test used four solutions prepared by the assessor to test the four primary tastes. The solutions were prepared as follows: 30 g of table salt was added to 1 L of deionized water for the salted solution, a sweet solution prepared as 30 g of refined sugar was dissolved in 1 L of deionized water, Sour solution was prepared as 90 mL of commercial 100% lemon juice added to 1 L of deionized water and unsweetened decaffeinated coffee act as the Bitter solution.During the test, each patient received 1 mL of each solution dropped in the center of the tongue. The patient was indicated whether the perceived flavor was sweet, salty, bitter, or acid. Deionized water was used as a mouthwash between the different solution tests to wash any excess and avoid any mix between tested solutions. The solutions were presented in random order. In contrast, the bitter taste was presented last as it altered subsequent taste perception. The answers were recorded as either yes or no taste for each solution. The patient was recorded as totally recovered if they could perceive all the primary tastes. The patient was considered partially recovered if they failed to perceive one of the primary tastes.The taste was assessed at the following intervals: during diagnosis, 1-week, 2-weeks, 3- week and 4 weeks post-treatment.