Deep caries can be directly treated with filling and restoration if the nerve (pulp) is not infected. 1. Deep dental caries is one of the common diseases in stomatology, which refers to the symptoms that appear when dental caries reaches the deeper layers of dental tissues; its clinical manifestations mainly include pain from hot and cold stimulation or biting pain, etc. Deep dental caries can be directly filled and restored if there is no infection of the nerve causing pulpitis. 2. If deep caries has no symptoms of pulpitis caused by infection of the nerve, the caries can be directly filled and repaired; on the contrary, if there are symptoms of pulpitis such as hot and cold pain, spontaneous pain or pain at night, it is necessary to carry out root canal treatment (i.e., extraction of the nerve treatment) to remove the inflamed pulp tissue in order to carry out the later filling and repair. Deep caries is recommended to consult a doctor for a clear diagnosis and timely treatment to avoid aggravation of the symptoms.