骨性Ⅱ类青少年上颌第一磨牙远中可用间隙在第二磨牙不同发育阶段的变化  

Changes in the distal available space of maxillary first molar at different developmental stages of the second molar in skeletal ClassⅡadolescents

作　　者：孙嘉田 刘琳 Sun Jiatian;Liu Lin(Graduate School of Dalian Medical University,Dalian 116044,China;Department of Orthodontics,Dalian Stomatological Hospital,Dalian 116021,China)

机构地区：[1]大连医科大学研究生院,大连116044 [2]大连市口腔医院口腔正畸科,大连116021

出　　处：《中华口腔正畸学杂志》2024年第1期6-10,共5页Chinese Journal of Orthodontics

摘　　要：目的观察骨性Ⅱ类均角青少年上颌第一磨牙远中可用间隙在第二磨牙不同发育阶段的矢状向特征及变化趋势。方法本研究为回顾性生长发育的横向研究,选取103例骨性Ⅱ类均角青少年患者锥形束CT数据,根据右侧上颌第二磨牙不同钙化发育阶段的影像学图像,分为T1、T2、T3、T4组(T1:牙冠完全形成且牙根未形成组,T2:牙根刚开始形成组,T3:牙根形成1/2组,T4:牙根形成3/4且根尖孔未闭合组),在矢状面上分别测量右侧上颌第一磨牙釉牙骨质界根方3 mm、6 mm和9 mm位置处牙根最远点到上颌结节最远点的距离,分别标记为L3、L6、L9。结果①在L6高度水平,男性T1、T2、T3、T4组第一磨牙远中可用间隙分别为(11.80±0.67)mm、(13.66±0.95)mm、(14.67±1.14)mm、(15.74±0.49)mm,女性T1、T2、T3、T4组第一磨牙的远中间隙分别为(11.44±0.92)mm、(13.13±0.84)mm、(14.29±0.88)mm、(15.40±1.11)mm;L3、L6、L9测量值男性大于女性,但无性别间的统计学差异;②L3、L6、L9在T1-T2、T2-T3、T3-T4的组间变化均有统计学差异,T1-T2、T2-T3、T3-T4阶段L3的增长量分别为(2.30±0.45)mm(P<0.001)、(1.40±0.55)mm(P=0.019)、(1.07±0.34)mm(P=0.003),L9的增长量分别为(1.58±0.28)mm(P<0.001)、(1.18±0.34)mm(P=0.001)、(0.93±0.31)mm(P=0.004),L3、L6、L9均为T1-T2的增长量最大,L3、L9为T3-T4的增长量最小。结论骨性Ⅱ类青少年上颌第一磨牙远中可用间隙的长度在T1-T4均有明显增加,但长度的增长量以T1-T2为最大,提示其矢状向生长潜力从T1至T4可能减缓。Objective To observe the sagittal characteristics and trends of distal available space of maxillary first molars at different developmental stages in adolescents with skeletal classⅡ.Methods Our study was a retrospective cross-sectional study of growth and development.Cone-beam computed tomography(CBCT)data of 103 adolescent patients with skeletal classⅡaverage angle were selected,The cases were divided into T1,T2,T3,and T4 groups(T1:tooth crown was completely formed and root was not formed,T2:tooth root began to form,T3:1/2 root formation,T4:3/4 root formation and apical foramen unclosed)according to the different calcification development stages of the right maxillary second molars.We then measured the distance from the distal point of the root to the distal point of the maxillary tubercle at 3 mm,6 mm and 9 mm above the maxillary first molar cemento-enamel junction in the sagittal plane,marked as L3,L6,L9,respectively.Results①At the L6 level,the distal available space of the first molar in T1,T2,T3,and T4 were(11.80±0.67)mm,(13.66±0.95)mm,(14.67±1.14)mm,(15.74±0.49)mm,respectively in males,and in females were(11.44±0.92)mm,(13.13±0.84)mm,(14.29±0.88)mm,(15.40±1.11)mm,respectively.Measurements of L3,L6,and L9 were all greater in males than that in females,but there was no statistical difference between genders.②The changes of L3,L6,and L9 were statistically different in the intergroups of T1-T2,T2-T3,and T3-T4,the growth of L3 in T1-T2,T2-T3,and T3-T4 stages were(2.30±0.45)mm(P<0.001),(1.40±0.55)mm(P=0.019),(1.07±0.34)mm(P=0.003),respectively,and the growth of L9 was(1.58±0.28)mm(P<0.001),(1.18±0.34)mm(P=0.001),(0.93±0.31)mm(P=0.004),respectively.L3,L6,and L9 all had the greatest growth in T1-T2,and L3 and L9 had the least growth in T3-T4.Conclusions The length of distal available space of maxillary first molar in classⅡadolescents increased significantly from T1 to T4,but the growth in length was greatest in T1-T2 stage,suggesting that its sagittal growth potential may decrease from T1

关 键 词：青少年 骨性Ⅱ类错[牙合] 上颌第一磨牙远中可用间隙 上颌第二磨牙 生长发育 

分 类 号：R783.5[医药卫生—口腔医学]