Due to the different distribution of nerves, the last tooth on the upper right side of the black generally does not cause numbness of the right lip and nostrils, if the formation of interstitial infection, it may cause numbness of the right lip and nostrils, but the chances are not great. The last tooth on the upper right side black may be due to caries, caries manifests itself in the form of demineralization of the tooth, pigmentation of the lesion site, locally yellowish-brown or brownish-brown, with the aggravation of caries, demineralization of the tooth body deepens, and the caries cavity becomes deeper and deeper, which may lead to pulpitis or periapical periodontitis. Due to the different distribution of nerves, it is unlikely to injure the nervous system controlling the right lip and nose, and localized symptoms of pain and numbness usually do not occur. However, if a maxillofacial gap infection develops and the local inflammation spreads to the surrounding soft tissues, it may cause numbness of the right lip and nostril, but the chances are small. In patients who develop caries, remineralization therapy and prophylactic resin filling can be used to prevent further caries progression. When the symptoms of numbness of the right lip and nostril appear, you should go to the hospital in time for scientific treatment under the guidance of professional doctors.