Alveolar bone remodelling and stability of mandibular incisors in adult patients after orthodontic treatment with premolar extractions: A prospective follow‐up study

Abstract

AbstractObjectiveTo evaluate alveolar bone remodelling and stability of mandibular incisors in adult orthodontic extraction patients.Materials and MethodsCone‐beam computed tomography images of 25 adult patients undergoing extraction were collected before orthodontic treatment (T1), after orthodontic treatment (T2), and after at least 1 year of retention (T3). The labial and lingual alveolar bone heights (ABH), thickness (ABT), and tooth movement of the mandibular incisors were measured during the retraction (T2–T1) and retention (T3–T2) periods. According to the tooth movement during the retention period, the mandibular incisors were further divided into stable and unstable groups, and the correlation between L1‐BMe and stability was evaluated.ResultsThe labial and lingual ABHs significantly increased after orthodontic treatment and decreased during the retention period. The lingual ABH was 7.36 ± 2.27 mm at T2 and 5.37 ± 1.98 mm at T3, indicating a great bone remodelling capacity. The labial ABT exhibited a significant increase during orthodontic treatment and a slight decrease during the retention period, while the lingual ABT showed an opposite trend. During the retention period, the root apex moved labially into the alveolar bone housing. L1‐BMe significantly increased during orthodontic treatment and decreased during the retention period. Compared to the stable group, lingual ABH and L1‐BMe at T2 was significantly higher, and lingual ABT was smaller in the unstable group.ConclusionPost‐treatment lingual alveolar bone defects of the mandibular incisors could recover to some extent during the retention period. There was a negative correlation between post‐treatment L1‐BMe and mandibular incisor stability.