Tanner-Whitehouse 2 method applied to the prediction of mandibular growth potentiality

与基于Tanner-Whitehouse 2方法（TW2）的英国儿童相比，日本儿童的骨骼成熟度提前。因此，在评价日本人下颌骨生长与骨骼成熟的相关性时，应采用日本儿童标准化的骨龄作为一般成熟度指标。在三种TW2方法中，RUS方法是最理想的。为了评估下颌骨生长潜力，采用多元回归分析，以最终下颌骨长度为标准变量，标准化骨龄为预测变量之一。青春期前预测的下颌骨终长与成年期实际长度的差异均在3 mm以下。除骨龄外，骨矿物质密度可能是预测下颌潜能的可用参数之一。另一方面，使用下颌骨标准生长曲线进行生长评价直观易懂，并且可以预测任何生长阶段的下颌骨长度。此外，这种方法可能适用于患有生长障碍的患者。上述结果提示，标准化TW2方法能较好地评估骨成熟度和下颌骨生长潜力，采用多元回归或标准生长曲线进行下颌骨生长预测在临床上对下颌骨的长期预测是有用的。在此之后，标准化的TW2方法将成为正畸领域骨骼成熟度和颅面生长时间的标准评估方法。

Skeletal maturation of Japanese children are advanced when compared with English children that based on Tanner-Whitehouse 2 method(TW2). Therefore, when the correlation between mandibular growth and skeletal maturation in Japabese are evaluated, bone age standardized by Japanese children should be used as general maturity indicator. RUS method is most desirable among three kinds of TW2 methods.To evaluate mandibular growth potentiality, multiple regression analyzes are performed by using final mandibular length as criterion variables and standardized bone age as one of the predictor variables. The difference of the values between final mandibular length predicted in prepubertal stage and actual length at adult stage were under 3 mm. Besides bone age, bone mineral density may be one of the available parameters to predict mandibular potentiality.On the other hand, growth evaluation by using of standard growth curve of the mandible was intuitively comprehensible, and prediction of the mandiblar length at any growth stage was possible. Also, this method may be possible on patients with growth disorders.These results suggested that standardized TW2 method are better assessment of skeletal maturation and mandibular growth potentiality, and growth prediction of the mandible by using of multiple regression or standard growth curve were clinically useful for long-term prediction of the mandible. After this, standardized TW2 method will be standard assessment for skeletal maturation and craniofacial growth timing in field of Orthodontics.