第一恒磨牙位于成人颌弓的中部,与颅面部有一定的恒定关系,Angle 称它为“(牙合)的锁钥”。它萌出早,釉质发育不良的机会多,以及(牙合)面解剖特点致使龋病发病率高。有人统计第一磨牙因龋坏拔除者占94%。儿童过早失去它会造成牙弓长度和宽度的改变,咬合紊乱产生错(牙合),咀嚼功能降低直接影响生长发育。如果适时拔除龋坏的第一磨牙,第二磨牙会顺势 The first permanent molars are located in the middle of the adult mandibular arch, with a certain constant relationship with the craniofacial area, which Angle calls “the key to the occlusion.” Its early eruption, enamel dysplasia more opportunities, as well as (occlusal) surface anatomical features resulting in a high incidence of dental caries. Some people account for the first molars due to caries removal accounted for 94%. Premature loss of children will result in changes in the length and width of the dental arch, occlusion disorders produce malocclusion, decreased chewing a direct impact on growth and development. If timely removal of decayed first molar, the second molar will be homeopathic