A total of 300 subjects (ambulant patients of the department of oralpathology and microbiology) filled out a questionnaire on lifestyle, dietary habit, previous history of medication, locality of residence, type of mobile used (CDMA or GSM; only group 2), duration of mobile phone usage (number of years and numbers of hours a week), use of headsets (only group 2), wired or not, associated symptoms like headaches, tingling of skin, rashes over the skin and warmth of the ear. Subsequently, subjects were divided into 2 groups (n=150 each) according to their mobile usage: 1) low mobile phone users (use of mobile phone for less than 5 years and less than 3 hours a week) and 2) high mobile phone users (mobile phone usage for more than 5 years and more than 10 hours a week). Exfoliated buccal mucosalcells were collected from the same side on which the subject used their mobile phones the most. Only in group 2, a comparative evaluation was done between both the sides of buccal mucosa (right and left).
mobile use for more than 5 years and more than 10 hours a week
receiving or making calls was considered as exposure, while net surfing and text messaging was not included; in group 2, 95 subjects were CDMA users and 55 subjects were GSM users and 70 subjects used wired headset while 80 were non-headset users