Effect of Khat Chewing on the Salivary pH before and after Using Mouthwashes

Document Type : Original Article


1 Section of Analytical Chemistry, Faculty of Pharmacy, Aden University, Aden, Yemen

2 Department of Analytical Chemistry, Faculty of Pharmacy, Aden University, Aden, Yemen


Background: Saliva is a biological fluid that has multiple protective functions. These functions can be
attained only if the saliva keeps certain physo-chemical properties such as pH.
Methods: The main purpose of the current study was to compare the salivary pH among khat chewers and
non-khat chewers before and after specific intervals (15, 30, and 60 minutes) of using three commercially
available mouthwashes (MWs). Thirty pharmacy student volunteers were divided into three groups of 10 for
the three MWs. Each group was then subdivided into 5 volunteers as khat chewer and non-khat chewer. The
statistical evaluation was carried out by using paired t-test and analysis of variance (ANOVA) for in vivo
study of salivary pH.
Findings: Low salivary pH in all khat-user volunteers before and after using MWs was indicated. There was
an increase in the salivary pH after 15 minutes of rinsing with the three selected MWs for both groups of
volunteers, after that there was a gradual decrease to the initial pH. The difference between the three groups
was not significant at baseline and after 15 minutes, but there was a significant difference after 30 and 60
minutes for the non-khat-chewing and khat-chewing volunteers.
Conclusion: It can be concluded that using MWs results in altering salivary pH and continuous khat chewing
lowers the baseline pH of saliva and ability to compensate the change of salivary pH.


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