Clinical investigation of causes of vertical root fracture in pulpless teeth;
无髓牙牙根纵裂原因分析
The results show that,all targets of the tension at break,elongation at break,percentage of elongation at break and scale degree of nonmedullar fibers of two experimental groups are much higher than those of comparative group (P<0.
结果表明：两种硫源对Ｆ２代杂种羊无髓毛的断裂强力、断裂伸长、断裂伸长率及鳞片度等指标均有极显著提高（Ｐ＜０。
The results showed that,all targets of stretched length,strength,degree of elasticity and sulphur content of nonmedullar fibers in those treatment groups were significantly higher or much higher than those of the other comparative groups (P<005 or P<001).
结果表明，二种硫源对Ｆ２代杂种羊无髓毛的伸直长度、强力、伸度及含硫量均有显著或极显著提高（Ｐ＜００５或Ｐ＜００１），对无髓毛的氨基酸总量、含硫氨基酸（胱氨酸）的含量也有提高。