Abstract: Abstract：Objective　Whether there is a relationship between the low angle malocclusion and cervical abnormalities was analyzed by the lateral cephalometric radiographs. The incidence of cervical vertebra abnormalities in low angle cases was statistically analyzed, and the relationship among cervical morphology, neck posture and craniofacial morphology was analyzed. Methods Sixty low angle cases of orthodontics in Harbin Medical University were selected as experimental groups in 2011-2019. Another 60 cases of average angle were randomly selected as the control group. All patients ranged in age from 16 to 40 years old. Based on data from the first 4 cervical fusions and posterior arch deficiency. The incidence of cervical anomalies was counted. And the correlation between the measurement of the craniofacial neck and cervical abnormalities was analyzed. Results The prevalence of cervical fusion in the low angle group was 56.7%, and the average angle group was 21.7%. Cervical fusion occurred mostly in the second and third cervical vertebrae. The difference between the two groups was statistically significant. There was no significant difference in the posterior arch deficiency. ML/OPT, ML/CVT, SNB, NSL/ML, FH/ML, NSL/NL, NL/ML, S-Go, N-Me, ANS-Me, S-Go/N-Me in the measurements of craniofacial was statistically significant between the two groups. Logistic regression analysis showed that the occurrence of cervical fusion was related to FH/ML. Conclusions　The incidence of cervical fusion in low angle patients is significantly increased, indicating that the occurrence of cervical fusion may be related to the vertical growth pattern of the face.

Key words: the low angle, cervical abnormalities, cervical fusions, posterior arch deficiency, cervical posture