Soft-bristled toothbrushes are recommended as they are gentler on the teeth and gums. Long-term use of hard-bristled toothbrushes can cause harm. According to the national standard of China, soft toothbrushes have a nominal wire diameter of less than 0.18 mm, while medium-bristle toothbrushes have a diameter between 0.18 and 0.22 mm. Bristles can be tested by lightly pressing them on the back of the hand. If there is a tingling sensation, the bristles are too hard. Soft bristles are beneficial for cleaning the gingival sulcus, the small gap between the teeth and gums. Hard bristles cannot effectively clean this area, leading to the accumulation of harmful bacteria and the formation of dental calculus. Soft bristles are also recommended for people with tooth sensitivity and can prevent issues like gingivitis. However, hard-bristled toothbrushes may have better cleaning effects on teeth with thick enamel. Sanding disposal is important to ensure that the bristles are smooth and do not pose any hazards, while replacing the toothbrush every three months is essential to maintain oral health and prevent bacterial accumulation.