Study on the transverse relationship of the mandible between different skeletal vertical patterns in patients with skeletal ClassⅠ malocclusion

To analyze the correlation between skeletal vertical patterns and mandibular dental arch width, basal arch width and the dental buccolingual inclination of patients with skeletal ClassⅠ.

The CBCT data of 62 skeletal ClassⅠ malocclusion patients were collected and divided into a high-angle group with 19 cases, a mean-angle group with 22 cases, and a low-angle group with 21 cases according to the GoGn-SN angle. Mandible 3D reconstruction of the three groups was performed using Dolphin software, and dental arch widths, basal arch widths and buccolingual inclination of canines, first premolars and first molars, were measured and statistically analyzed respectively.

Mandibular dental arch width showed no significant difference among the three groups (P＞0.05). The basal arch widths of mandibular canines and first premolars in low-angle group were larger than those in the other groups (P＜0.05). The buccolingual inclinations of mandibular canines and first premolars in high-angle group were larger than those in the other groups (P＜0.05). The buccolingual inclination and basal arch width of the first molars among the three groups showed no significant differences (P＞0.05). Pearson correlation tests showed that the basal arch widths of mandibular canines and first premolars were negatively correlated with GoGn-SN angle. Excluding the influence of dental arch width and basal arch width, there was still a significant positive correlation between the buccolingual inclination of mandibular canines and first premolars and the GoGn-SN angle (P＜0.05).

The width of the basal bone arch between different skeletal vertical patterns mainly differs in the canine segment and the premolar segment, and the difference in the buccolingual inclination of the teeth is mainly to compensate for the difference in the GoGn-SN angle. In clinical practice, individualized therapy should be adopted according to the differences to achieve the long-term efficacy of correction.