Abstract
INTRODUCTION: The objective of this study was to observe the effects of the duration of handheld mobile phone usage on the salivary flow, salivary immunoglobulin A (IgA) level, and salivary markers for oxidative stress. MATERIALS AND METHODS: Eighty-one students were categorized into three groups based on their duration of mobile phone usage after age- and gender-matching. Students were grouped as: mobile phone usage <20 min/day (Group A), mobile phone usage 20-60 min/day (Group B), and mobile phone usage >60 min/day (Group C). Saliva was collected to evaluate salivary flow rate, salivary IgA level, and salivary markers for oxidative stress. RESULTS: The salivary flow rate showed no statistically significant difference between the three groups (P = 0.180). There was no statistically significant difference in the salivary IgA between the three groups (P = 0.237). There was a statistically significant difference in the malondialdehyde (MDA) level between the three groups (P = 0.042). On pair comparison between the groups, group B and group C had a statistically significant difference (P = 0.019) in the MDA level. There was no statistically significant difference in the salivary thiol level between the three groups (P = 0.237). CONCLUSION: The duration of handheld mobile phone usage did not show any significant effects on the salivary flow rate, salivary IgA, and thiol levels. There was an increase in the salivary MDA concentration in subjects using handheld mobile phones for a longer duration, indicating higher oxidative stress in salivary glands exposed to mobile phone radiofrequency electromagnetic waves for a longer duration.