A longitudinal study on the skeletal maturity of the hand and wrist among various malocclusion groups (I)

Growth and development evaluation of patients with growth potential is of great importance for orthodontic treatment planning. Timing of orthodontic intervention greatly depends on one's developmental status, thus if there is a difference in skeletal maturation among malocclusion types different treatment timing should be applied. The objective of this study was to evaluate and compare skeletal maturation among different malocclusion types. The samples used in this study was 38 Class I, 36 Class II and 33 ClassIII females aging from 8 to 10 years. Handwrist X-rays were taken with 6 month interval till 12-13 years of age. The results were as follows. 1. There was no skeletal maturity difference among different malocclusion types. 2. The hamular process of hamate was observed at $9.16\pm0.72$ years, pisiform bone at $9.13\pm0.71$ years and the ulnar sesamoid at $10.34\pm0.84$ years. 3. The timing of epiphyseal capping on the third finger was $10.96\pm0.80$ years for distal phalanx and $11.27\pm0.87$ years for middle phalanx, $11.12\pm0.85$ years for proximal phalanx of the first finger, $11.21\pm0.82$ years for radius and $11.62\pm0.85$ years for middle phalanx of the fifth finger. 4. The appearance of pisiform bone showed high correlation with appearance of hamular process of hamate(r=0.91) and ulnar sesamoid bone appearance showed high correlation with advanced ossification of hamular process(r=0.86). Timing of epiphyseal capping among different parts showed high correlation(r=0.80-0.90). 5. The shape of middle phalanx of the fifth finger showed the highest variability ($20.6\%$).ope