The GUM Technique toothbrush features a unique handle designed to help position the brush so that the bristles reach under the gumline and where dental plaque can build up and cause gingival inflammation leading to gum diseases. The Quad-Grip handle has a unique design that helps you always hold the brush the way most dental professionals do-at 45 degrees. Whether you are left- or right-handed, brushing upper or lower teeth, the handle intuitively helps you form the 45-degree angle that is more effective at cleaning away the dental plaque from both gums and teeth. This makes sure you have the right dental "technique." The brush head features the Dome Trim® bristle design. The raised center bristles have been trimmed to form a dome shape that provides greater contact with the tooth surface and reaches under the gum line. When the toothbrush is angled at the widely recommended 45 degrees to the tooth (Bass technique), the bristles can easily reach under the gumline and into the sulcus to clean away dental plaque. The outer row of bristles is slightly more flexible than the center rows so that the soft, more flexible bristles will gently clean under the gum while the center, slightly stiffer rows will clean the tooth surfaces. Together the design of both the handle and the brush head help you clean in those areas where gum disease often starts-under the gumline.