Private practice, Nocciano, Pescara, Italy.
Department of Medical, Surgical and Health Sciences, School of Dentistry, University of Trieste, Trieste, Italy.
Am J Orthod Dentofacial Orthop. 2022 Dec;162(6):937-946. doi: 10.1016/j.ajodo.2021.07.031. Epub 2022 Oct 1.
Despite the substantial prevalence of skeletal Class II Division 1 malocclusion, only a few studies analyzed the maxillomandibular growth changes in these subjects with contrasting results. This study compared the longitudinal maxillomandibular growth changes in growing subjects with Class I and II skeletal relationships, specifically during the circumpubertal growth phase assessed by the modified third finger middle phalanx maturation (MPM) method. An attempt to uncover any maxillomandibular growth peak in subjects with Class II relationship has been followed.
From the files of the Burlington Growth Study, a total of 32 subjects (13 males, 19 females) with at least 7 annual lateral cephalograms taken at 9 and 16 years old were included and equally distributed between Class II and Class I groups matched for sex. Overall changes in 12 cephalometric parameters were calculated, and maxillomandibular growth peak was also identified individually and used to register subjects according to the year of growth peak ± 2 years. According to this procedure, annualized changes (trends) were analyzed along with the corresponding prepubertal, pubertal, and postpubertal MPM stages.
No significant differences were seen between subjects with Class I and II skeletal relationships at 9 and 16 years, except for the parameters of the sagittal maxillomandibular relationship, such as ANB angle. Overall, changes for all the cephalometric parameters were similar between the groups, except for the CoGn distance increment that was significantly lower in the subjects with a Class II relationship. In both groups, the annual changes in CoA, CoGn, and CoGo distances showed a clear peak at the time point corresponding to a median MPM stage 3.
In subjects with a skeletal Class II relationship, mandibular deficiency appears to be mostly established during the prepubertal growth stage and further aggravated during puberty. However, the maxillomandibular growth trend in subjects with Class II relationship is generally similar to that of subjects with a Class I relationship, including the existence of a pubertal peak.
尽管骨骼 II 类 1 类错畸形的患病率相当高，但只有少数研究分析了这些具有对比结果的患者的上下颌骨生长变化。本研究比较了生长中的 I 类和 II 类骨骼关系患者的纵向上下颌骨生长变化，特别是使用改良的第三指中节指骨成熟度（MPM）方法评估的青春期前生长阶段。尝试发现 II 类关系患者的任何上颌骨和下颌骨生长高峰。
从伯灵顿生长研究的档案中，共纳入 32 名患者（13 名男性，19 名女性），至少有 7 次 9 岁和 16 岁的侧位头颅侧位片，分为 II 类和 I 类两组，性别匹配。计算了 12 项头影测量参数的总体变化，并单独确定了上颌骨和下颌骨生长高峰，并根据生长高峰的年份±2 年对患者进行注册。根据该程序，分析了年度变化（趋势）以及相应的青春期前、青春期和青春期后 MPM 阶段。
9 岁和 16 岁时，I 类和 II 类骨骼关系患者之间除了矢状颌骨关系的参数，如 ANB 角外，没有显著差异。总体而言，两组患者的所有头影测量参数的变化相似，除了 CoGn 距离的增量，II 类关系患者的增量明显较低。在两组患者中，CoA、CoGn 和 CoGo 距离的年变化在对应于中位数 MPM 阶段 3 的时间点显示出明显的高峰。
在骨骼 II 类关系的患者中，下颌骨不足似乎主要在上颌前生长阶段建立，并在青春期进一步加重。然而，II 类关系患者的上下颌骨生长趋势与 I 类关系患者大致相似，包括青春期高峰的存在。
