839名5至18岁健康人下颌角与手骨、全身骨密度的相关性研究

Correlation of bone mineral density of the mandibular angle, hand and total body in 839 healthy individuals aged from 5 to 18 years

目的 探讨5至18岁健康人下颌角骨密度与手骨、全身骨密度的相关性,以期为临床提供参考.方法 选择广州市5所中小学5至18岁健康人839名（男性422名,女性417名）,按年龄分组,并分性别统计.用双能X线骨密度仪测量受试者双侧下颌角、非惯用手及全身骨密度,并进行Pearson相关性分析.结果 下颌角骨密度随年龄增长而增加,女性在12至16岁间呈现快速增长,16岁后增速变慢;男性在14岁后快速增长,并持续至18岁未见减慢.12、13、14、15、16、17岁组女性下颌角骨密度[（0.95±0.19）、（1.01±0.17）、（1.11±0.17）、（1.25±0.13）、（1.28±0.14）、（1.30±0.13）g/cm2]均显著高于同年龄组男性（P＜0.05）;5～11岁组、18岁组男女差异无统计学意义（P＞0.05）.男性下颌角骨密度与年龄呈强相关（r=0.696,P＜0.001）,与手骨密度呈强相关（r=0.779,P＜0.001）,与全身骨密度呈极强相关（r=0.831,P＜0.001）.女性下颌角骨密度与年龄呈强相关（r=0.795,P＜0.001）,与手骨密度呈极强相关（r=0.839,P＜0.001）,与全身骨密度呈极强相关（r=0.872,P＜0.001）.结论 5至18岁健康人下颌角骨密度随年龄增长而增加;下颌角骨密度与手骨、全身骨密度密切相关.

Objectives To investigate the correlation of bone mineral density（BMD） of mandibular angle,hand and total body in healthy individuals aged from 5 to 18 years.Methods Eight hundred and thirty-nine healthy individuals from 5 to 18 years old（422 males,417 females） in 5 primary and secondary schools in Guangzhou were divided into 14 age groups.Dual energy X-ray absorptiometry（DXA） was used to measure the BMD of mandibular angle,hand and total body.The data were statistically analyzed using Pearson correlation analysis.Results The BMD of mandibular angle increased with age.In females,the BMD of mandibular angle increased quickly from 12 to 16 years old,and its increasing rate gradually slowed down after 16 years old.In males,the BMD of mandibular angle increased quickly after 14 years old,and its increase had not been stopped until 18 years old.Females in 12,13,14,15,16,17-year-old group had significantly higher mandibular angle BMD[（0.95±0.19）,（1.01±0.17）,（1.11±0.17）,（1.25±0.13）,（1.28±0.14）,（1.30±0.13） g/cm2] than males in the age-matched group（P〈0.05）.There was no significant difference between mandibular angle BMD in males and in females at the age of 18,and from 5 to 11 years old（P〉 0.05）.For males,the mandibular angle BMD was highly correlated with age（r=0.696,P〈0.001）,hand BMD （r=0.779,P〈0.001） and total body BMD（r=0.831,P〈0.001）.For females,the mandibular angle BMD was highly correlated with age（r=0.795,P〈0.001）,hand BMD（r=0.839,P〈0.001） and total body BMD（r=0.872,P〈0.001）.Conclusions The mandibular angle BMD in healthy individuals from 5 to 18 years old increased with age.The mandibular angle BMD was closely related to hand BMD and total body BMD.