If the gums are significantly receding or if there is a significant gap in the orthodontic process and flossing is not working well, you will need to use a gap brush in conjunction with your teeth. There are various types of interdental brushes, choose the one that is slightly larger than the gap between the teeth. When brushing the upper front teeth, the interdental brush is inserted diagonally downward into the gap; when brushing the lower front teeth, the interdental brush is tilted slightly upward; when brushing the back teeth, relax the muscles. Brush each tooth gap back and forth 2-3 times to avoid damaging the gums as much as possible. If the gap is too small for the tooth brush to pass through, do not force the tooth brush to be used. You can use the crevice brush without toothpaste. Wash and dry the brush after use. When the toothbrush bristles bifurcate or the wire unscrews the spiral, replace it in time.