BACKGROUND AND OBJECTIVE: Salivary secretion is almost entirely regulated by the nervous system. This secretion is mostly increased in response to gustatory sensations and jaw movements during chewing. This study was conducted to evaluate the effects of dominant chewing side on amylase enzyme activities.

METHODS: Overall, 48 healthy individuals within the age ranges of 6-12 and 41-61 years, with no history of cell phone use, took part in this experimental study. The saliva samples of both chewing sides were obtained separately from the Stensen's foramen, using a capillary tube. The level of amylase activity (U/L) was evaluated, based on the dominant chewing side.

FINDINGS: As the results indicated, 28 subjects preferred the right side for chewing and 20 subjects frequently chewed on the left side. The mean amylase activity in the former group was 27901±38141 U/L on the right side and 60954±51325 U/L on the left side (p=0.000). The mean amylase activity in the latter group was 52995±39857 U/L on the right side and 25464±22344 U/L on the left side (p=0.000). There was a significant relationship between amylase activity and the dominant chewing side (p<0.001).

CONCLUSION: The results of this study showed that the activity of amylase enzyme, secreted from the parotid glands, decreases in the dominant chewing side.