Correlation between craniofacial growth and upper and lower body heights in subjects with Class I occlusion

ABSTRACT Objective: To correlate skeletal age, standing height, upper and lower body lengths, and selected craniofacial growth features in a sample of growing individuals, and to model craniofacial growth using multivariate regression. Methods: This was a retrospective cross-sectional study with 447 African black boys and girls, between the ages 8 and 16 years, who attended the dental clinic at one hospital. The skeletal maturational age was determined from hand-wrist radiographs using the Greulich and Pyle atlas. Craniofacial measurements representing maxillary length (Ar-ANS), mandibular length (Ar-Gn), and lower facial height (ANS-Me) were calculated from lateral cephalograms in habitual occlusion. Body lengths were clinically measured in centimeters. Results: Moderate correlations (r=0.42 to 0.68) were observed between skeletal age and the three selected craniofacial measurements. Statistically significant correlations were also found between the craniofacial measurements and both upper and lower body lengths. The mandibular length had a stronger correlation with the upper body length than with the lower body length. Multiple regression analyses to determine maxillary and mandibular lengths suggested that sex, upper and lower body lengths might be used to determine maxillary length; while skeletal age, upper and lower body lengths might help determine mandibular length. Conclusions: Based on the relatively strong correlation between upper body length and mandibular length, further research in this area may warrant its use as a predictor for mandibular growth modification timing.

摘要
研究目的：针对8至16岁的生长发育个体样本，探究骨龄（skeletal age）、站立身高、上半身长、下半身长及选定的颅面生长特征之间的相关性，并通过多元回归法构建颅面生长模型。
研究方法：本研究为回顾性横断面研究，纳入447名年龄介于8至16岁的非洲黑人男女青少年，所有受试者均就诊于某医院牙科诊所。采用格雷利希-派尔图谱（Greulich and Pyle atlas）对手腕骨X线片（hand-wrist radiographs）进行分析，以确定骨骼成熟年龄。在习惯性咬合位（habitual occlusion）下，通过头颅侧位片（lateral cephalograms）测量以下颅面指标：上颌骨长度（Ar-ANS）、下颌骨长度（Ar-Gn）及下面部高度（ANS-Me）。身体各段长度均以厘米为单位进行临床测量。
研究结果：骨龄与三项选定的颅面测量指标间存在中等程度相关性（相关系数r=0.42~0.68）。颅面测量指标与上、下半身长均存在统计学意义上的显著相关性。下颌骨长度与上半身长的相关性强于其与下半身长的相关性。针对上颌骨与下颌骨长度的多元回归分析显示，性别、上半身长与下半身长可用于预测上颌骨长度；而骨龄、上半身长与下半身长则有助于预测下颌骨长度。
研究结论：鉴于上半身长与下颌骨长度间存在较强相关性，后续相关研究可考虑将其作为下颌骨生长改建时机的预测指标。