Correlation Analysis of Maxillary Molars Inclination with Impacted Position and Growth Direction of Maxillary Third Molar

doi:10.13701/j.cnki.kqyxyj.2022.06.007

Abstract

Abstract: Objective: To measure the mesial and distal inclination of maxillary molars in patients with class I, and to explore its correlation with the impacted depth and impacted direction and growth direction of maxillary third molars. Methods: The CBCT data of 67 patients with Angle class I were selected before treatment. According to the impacted depth of the third molar, they were divided into three groups: normal eruption type, medium position type, and low position type. According to the impacted direction of the third molar, it was divided into two groups: mesial type and distal type. Taking the palatal plane as the reference plane, the inclination of the maxillary molars were measured, and the data were statistically analyzed. Results: (1) There was no significant difference in the measured values between different gender groups (P>0.05). (2) When the impacted depth and impacted direction of maxillary third molars were different, there were significant differences in the inclination of maxillary first molars and second molars (P<0.05). (3) The inclination of maxillary first and second molars were positively correlated with the impacted depth of third molars (P<0.05), but not significantly correlated with the growth direction of third molars (P>0.05). The inclination of first molars was positively correlated with the impacted direction of third molars (P<0.05). (4) The impacted depth of maxillary third molar was not correlated with its growth direction (P>0.05), but positively correlated with its impacted direction (P<0.05). Conclusion: The lower the impacted of the third molar, the more distal inclination of the maxillary molar. The more mesial the impacted direction of the third molar, the more distally inclined the maxillary first molar.

Key words: molar inclination, molar interruption, third molar, CBCT

XU Yishan, LI Zhenzhen, WU Yao, SI Chao, XU Jingyu, YU Ling, ZHANG Huichao, YANG Luyi. Correlation Analysis of Maxillary Molars Inclination with Impacted Position and Growth Direction of Maxillary Third Molar[J]. Journal of Oral Science Research, 2022, 38(6): 518-522.

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