磨蚀牙
Results the average attrition gradation of the teeth in Neolithic population was 3.88. The attrition degree of the first molar was greater than that of the second!───结果新石器时期人类牙齿的平均磨耗级别是3.88级，磨耗程度第一磨牙大于第二磨牙、大于第三磨牙。
attrition rate───[军]损耗率；退学率
anterior teeth───[解剖]前牙
attribution theory───归因理论
attrition rates───[军]损耗率；退学率
attribution theories───归因理论
attrition───n.摩擦；磨损；消耗
attritional───磨耗的；磨损的
gritted teeth───咬牙切齿（gritted是grit的过去式）；咬紧牙关（gritted是grit的过去式）
rotten teeth───烂牙