Oral-B CrossAction brush heads are perfectly angled to get deep in between teeth. The CrissCross bristles are set at a 16 degree angle to effectively clean along the gumline and perfectly angled get deep in between teeth for 100 percent more plaque removal (versus a regular manual toothbrush). The round head cleans better for healthier gums (versus a regular manual toothbrush), it's designed with dentists, and compatible with Oral-B rechargeable electric toothbrush handles, except for Oral-B sonic toothbrushes. Replace your brush head every three months to relive that new brush feeling.