There are many causes of pain when a tooth is touched, but the most common is acute pulpy periapical infection, the symptoms of which are pain when bitten or touched. Initially, there is no spontaneous pain or only a mild dull ache. Patients often report an uncomfortable sensation in the apical area of the affected tooth, the tooth is woody and it feels like the tooth has a floating sensation. The disease then develops, and when the patient bites, the affected tooth first touches the opposing tooth, and biting hard can temporarily relieve the pain because the biting pressure temporarily squeezes the blood out of the blood vessels filled with blood in the periapical membrane, and the patient feels slightly less painful. As the condition develops, the blood in the periapical area pools, and if the affected tooth is bitten down again instead, the pain is aggravated, so the patient is reluctant to eat at this time, and eating is affected. In case of periapical infection, a complete root canal treatment is done.