Brush your teeth every day and there are still mistakes? Not necessarily! If you don’t do it right, you may not get what you want. In my clinical practice, I often see patients with cervical wedge defects caused by improper brushing (horizontal brushing). Severe wedge defects can lead to dentin hypersensitivity, pulpal and periapical disease, and even crown fracture. Some people come to the clinic with a feeling of sour teeth when eating fruit, or feel sensitive when eating hot or cold food or touching, but more people may just think they have tooth sensitivity and use desensitizing toothpaste indiscriminately. Desensitizing toothpaste does have a desensitizing effect, but wedge-shaped defect is not an indication for desensitizing toothpaste. The cause of wedge-shaped defect is complicated, but the main reason is caused by improper brushing method, in addition to personal constitution, saliva acidity, diet, stomach disease acid reflux, etc.; in addition, the cervical part of the tooth is the weak link of the tooth structure, the lowest resistance to wear, while the unbalanced bite caused by the stress fatigue of the cervical part of the tooth also has a certain relationship with the occurrence of wedge-shaped defect. The first step is to seek help from a dentist to repair the defect with resin material as soon as possible to improve the stress concentration in the cervical region. In addition to this, it is necessary to have the dentist adjust the occlusal interference of the teeth, equalize the bite force of the whole mouth, and teach the correct brushing method. If you have tooth sensitivity, don’t use desensitizing toothpaste blindly after reading this article, go to your dentist to see if your sensitivity is caused by a wedge-shaped defect, and treat it promptly.