Background To master the distribution and changing characteristics of dental diseases MESHD is of great significance for the dental emergency MESHD center in order to strengthen the treatment abilities of medical staff and the effective use of emergency MESHD resources in the face of public health emergencies MESHD of highly infectious respiratory diseases MESHD. Methods The medical records of 4158 cases of dental emergency MESHD patients from 2019 to 2020 were retrospectively analyzed,with patients being divided into the pre-SARS-COV-2 group and the during SARS-COV-2 group according to the date of their admittance to the dental emergency MESHD center.The dental emergency MESHD patients demographicsn data,day and time,diagnoses,treatment approaches were compared before and during the SARS-COV-2. Results During the SARS-COV-2,the number of dental emergency MESHD visits increased by 29.7% compared with those before the SARS-COV-2.The peak of the number of patients at weekends and at night is not obvious compared with the pre-SARS-COV-2 group.Duing the SARS-COV-2 Male TRANS(n=286,58.1%) were more likely than female TRANS(n=206,41.9%) to visit the dental emergency MESHD center for trauma P<0.05, female TRANS(n=242,60.8%) were more likely than male TRANS(n=156,39.2%) to visit the dental emergency MESHD center for Acute gingivitis MESHD gingivitis HP and Acute pericoronitis MESHD P<0.05.A major diagnoses change is Acute Pulpitis MESHD (K04.0) and Acute apical periodontitis MESHD periodontitis HP (K04.4) increased by 9.2%,Acute gingivitis MESHD gingivitis HP (K05.0) and Acute pericoronitis MESHD(K05.2) increased by 3.5%,Open wound of lip and oral cavity (S01.5) fell HP 17.9%,others (non- emergency MESHD diseases MESHD) increased by 6.8%,compare with the pre-SARS-COV-2.Among the treatment methods,during the pre-SARS-COV-2,304（17.7%）received a prescription for Antibiotics and Analgesics,1485(86.5%) received a prescription for local treatment.During the SARS-COV-2,958（39.2%）received a prescription for Antibiotics and Analgesics,1636(67.0%) received a prescription for local treatment. Conclusion SARS-COV-2 led to changes in the characteristics of dental emergency MESHD patients.Trauma,Acute Pulpitis MESHD,Acute periodontitis MESHD periodontitis HP Acute periodontitis MESHD periodontitis HP are the leading reason why patients go to the dental emergency MESHD.The dental emergency MESHD center should optimize the treatment procedures,optimize the staffing and reasonably allocate materials according to the changes,to improve the on-site treatment capacity and provide adequate dental emergency MESHD care. .