Innovative iO technology extends to the very tips of the bristles. The cushioning effect of the outer bristles safeguards the gums and provides a comfortable sensation in the mouth. The bristles on the distinct, round brush head envelop each tooth individually. Dentists advise replacing the brush head every three months for optimal cleaning. Designed specifically for the Oral-B iO toothbrush, which is the most recommended toothbrush brand by dentists globally. Included in the package are 4 Oral-B iO gentle cleaning brush heads.