Pulpitis in a 5 year old child needs to be treated with pulpotomizing and drainage, but the younger the child, the less cooperative he/she is, so the doctor needs to be more experienced and quicker to complete the treatment as early as possible within a very short period of time with relative cooperation. Generally, a high-speed turbine drill is used to open the pulp of a baby tooth that has been identified as having pulpitis, and the top of the pulp chamber is removed, and the pulp is extracted directly with a dental instrument. After the extraction, the root canal treatment of the milk tooth is completed by filling the pulp chamber of the milk tooth with a paste that is routinely mixed with a non-absorbable substance such as cementum tip, and if there is a condition to consider the production of a preformed crown to protect the milk tooth.