Establishment of Cervical Vertebral Bone Age Based on Pattern Matching Method

点击翻译按钮获取中文摘要

The purpose of this study was to establish a "cervical vertebrae bone age" (VA) as maturity indicator and design a formula to predict mandibular growth using VA.First, using 200 cephalometric radiographs for females between 7 and 15 years of age, the eight parameters on third and forth cervical vertebrae of cephalometric radiographs were measured. Multiple regression formula was used to calculate VA by using the proportional measurements of these parameters. The formula was as follows : VA=0.80+6.05×3^<rd> vertebral anterior height (AH)/antero-posterior length (AP)+9.63×4^<th> vertebral AH/APNext, by using another set of materials (66 females between 8 and 13 years of age), the reliability of this formula was estimated. Correlation coefficient between VA and bone age (Tanner-Whitehouse 2 method) using hand wrist X-ray films was higher than the correlation between VA and chronological age. Difference of these correlation coefficients was significant (p<0.05). VA was found to be useful as physiological age indication.Third, prediction of mandibular growth was examined. The mandibular length (Cd-Gn) of 21 females were measured on both initial examination (7-12 years of age) and last examination (over 17 years), and VA was calculated on initial examination. The formula was as follows : Growth potential of the mandible=-2.63+36.85×VALastly, automatic estimation of skeletal age based on hand-wrist radiographs was examined as the preliminary study. The pattern matching method was applied. It was confirmed that this method could be applied to VA.