The Study Of Relationship Between Incisor Labial Inclination And Alveolar Bone Morphology With Adult Skeletal Class Ⅱ Malocclusion By CBCT

Objectives:To study the correlation between the mandibular incisor labial inclination and the alveolar bone morphology in patients with Uygur and Han nationalities adults and skeletal class Ⅱ malocclusions by CBCT.Method:46 Uygur and 46 Han patients with skeletal class Ⅱ malocclusion between the ages of 18 and 30 years were selected and scanned for the lateral cephalometric films and CBCT.The mandibular incisor labial inclination was measured on the lateral cephalometric films by the geometric sketch board software,and divided into the labial title group and the lingual title group,and the mandibular incisor alveolar by the Mimics software.Result:In the labial title group,the thickness of the labial alveolar bone(TB)and the total alveolar bone thickness at the apex(TB+TL)of the Han nationality were greater than those of the Uygur,and the difference was statistically significant(P<0.05).In the lingual title group,the lingual alveolar bone(TL)and TB+TL of the Han nationality were larger than those of the Uygur,and the difference was statistically significant(P<0.05).The TB and TB+TL in the labial title group of the Uygur and Han nationalities were larger than that of the lingual title group.The lingual attachment height(HL)of the lingual title group was larger than that of the labial title group,and the difference was statistically significant(P<0.01).The mandibular incisor labial inclination of Uygur and Han nationalities was positively correlated with TB and TB+TL,and negatively correlated with HL.Conclusion:the thickness of labial alveolar bone and the total thickness of alveolar bone of the Uygur are thinner than those of Han nationality.when the incisor labial inclination increased,the thickness of labial alveolar bone and the total thickness of the alveolar bone also increased,and the attachment height of the lingual side decreased.