Study on Root Resorption of Mandibular Second Molars with Long Distance Mesialization

doi:10.13701/j.cnki.kqyxyj.2020.06.023

Abstract

Abstract: Objective: To explore the root resorption of mandibular second molars after long distance (≥5mm) mesialization. Methods: A total of 45 mandibular second molars in 36 completed cases were retrospectively analyzed. The root length and axis inclination angle of the orthodontic molars were measured by direct digital panorama. According to the initial axial inclination of the molars, they were divided into group A (axial inclination <86.42°) and group B (axial inclination ≥86.42°). According to the change of axial inclination, they were divided into group C (change <10°) and group D (change ≥10°). The root resorption was calculated and the effect of axis inclination on root resorption was analyzed. Results: The root length was shortened (P<0.01). The mesial and distal root resorption values were approximately (P>0.05). The average root resorption was (0.97±0.40) mm. There was no significant difference between group A and group B in root resorption (P>0.05). Group C and group D had statistical significance only in the amount of distal root resorption (P<0.05). Conclusion: The root resorption of mandibular second molars after long distance mesialization is small and generally has no clinical significance. The change of axial inclination of the molars has a certain effect on the root resorption of the distal root. Orthodontic treatment should be started as soon as possible after the molar loss.

Key words: mandibular second molars, molar mesialization, root resorption, axis inclination

PAN Enjiu, DU Qingling, ZHU Jiejing, ZOU Mingyuan, GONG Guoliang, LIN Xinping. Study on Root Resorption of Mandibular Second Molars with Long Distance Mesialization[J]. Journal of Oral Science Research, 2020, 36(6): 603-606.

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