Main product description The iO 4 electric toothbrush uses the best technology from Oral-B, combining a dentist-inspired round cleaning head with fine micro-vibrating bristles for a professional cleaning sensation in the comfort of your home. The smart pressure sensor helps prevent cleaning your gums too hard or too gently. Gum protection will warn you about the time you spend brushing your teeth with too much pressure. For best results, replace the Oral-B iO brush head every 3 months.