正常情况下,人类乳牙数目为20颗,恒牙数目为32颗,当恒牙列或乳牙列出现多于此数目的牙齿时便可称为多生牙。现将我院口腔科2016年9月发现的1例右侧上颌第四磨牙近中阻生的患者报道如下。牙石(+),牙龈缘暗红,肥厚,探诊易出血,牙周袋约4mm。牙体叩诊正常,冷测正常,松动I°。牙冠与17 Under normal circumstances, the number of human deciduous teeth is 20, the number of permanent teeth is 32, when the permanent dentition or deciduous teeth appear more than this number of teeth can be referred to as multiple births. Now in our hospital Department of Stomatology in September 2016 found in 1 case of right maxillary fourth molar near-obstruction of patients reported as follows. Tartar (+), gingival margin dark red, hypertrophy, probing bleeding, periodontal pocket about 4mm. Tooth percussion normal, normal cold test, loosen I °. Crown with 17