Agenter Michael K, Harris Edward F, Blair Robert N
Department of Orthodontics, College of Dentistry, University of Tennessee, Memphis, TN 38163, USA.
Am J Orthod Dentofacial Orthop. 2009 Dec;136(6):795-804. doi: 10.1016/j.ajodo.2007.12.030.
Malocclusion is an increasingly common, multifactorial problem. The most prevalent malocclusion results from excess tooth size compared with the size of the supporting bone; this creates a tooth-size arch-size discrepancy. Although the causes of malocclusion are obscure in most instances, a contributing factor appears to be tooth size. The goal of this study was to test whether the dimensions of the crowns of the permanent teeth differ in young men with naturally good occlusions compared with those who required orthodontic treatment.
Tooth crown dimensions (mesiodistal and buccolingual) were measured in 2 samples of American white men. One group (n = 42) had naturally good occlusion; the other group (n = 90) required orthodontic treatment to correct tooth-size arch-size discrepancy.
The means of 23 of the 24 tooth crown dimensions-involving the 14 tooth types (central incisor through first molar) in both arches-were significantly larger in subjects with malocclusions than in those with good occlusions. Multivariable analysis showed that mesiodistal size of the maxillary lateral incisor was the most significant difference between the 2 samples, but this might reflect the composition of the sample (maxillary lateral incisor size is notoriously variable in white men).
Tooth size is not necessarily the foremost cause of malocclusion in a patient, but it should be evaluated.
错牙合畸形是一个日益常见的多因素问题。最常见的错牙合畸形是由于牙齿大小与支持骨大小相比过大所致；这就造成了牙齿大小与牙弓大小的差异。尽管在大多数情况下错牙合畸形的病因尚不清楚，但一个促成因素似乎是牙齿大小。本研究的目的是测试与需要正畸治疗的男性相比，具有自然良好咬合的年轻男性恒牙冠的尺寸是否存在差异。
在美国白人男性的2个样本中测量了牙冠尺寸（近远中径和颊舌径）。一组（n = 42）具有自然良好的咬合；另一组（n = 90）需要正畸治疗以纠正牙齿大小与牙弓大小的差异。
在24个牙冠尺寸中的23个尺寸的均值——涉及两个牙弓中的14种牙齿类型（中切牙至第一磨牙）——错牙合畸形患者显著大于咬合良好的患者。多变量分析表明，上颌侧切牙的近远中尺寸是两个样本之间最显著的差异，但这可能反映了样本的构成（白人男性上颌侧切牙的大小差异很大）。
牙齿大小不一定是患者错牙合畸形的首要原因，但应该进行评估。
