聚酰胺-胺诱导牙本质表面矿物沉积的体外实验

The polyamidoamine induced mineral deposition on dentin surface in vitro

目的:探讨3.0代聚酰胺-胺(3.0PAMAM)在牙本质表面诱导生成的矿化物封堵牙本质小管的效果。方法:选取16颗健康正畸牙,制备16个脱矿牙本质样本,按随机数字表法随机选择7个样本作为对照组,7个作为实验组,余2个样本不做任何处理作为脱矿牙本质组。对照组用去离子水处理,实验组用3.0 PAMAM处理之后将各组样本同时浸入人工唾液2、4周后,通过SEM观察每组牙本质小管的微观形貌,X射线能谱仪(EDS)检测牙本质表面沉积物的钙、磷元素含量,并采用两独立样本t检验分析比较4周后2组样本的Ca/P值。结果:SEM观察显示实验组牙本质样本矿化程度随矿化时间延长,表面矿化物逐渐形成,处理4周后完全覆盖所有的牙本质小管口。对照组样本表面矿化物较少,牙本质小管口仍然开放。EDS结果显示沉积物Ca/P值实验组(1.49±0.16)高于对照组(1.18±0.20)(P<0.05)。结论:3.0代聚酰胺-胺对敏感牙本质有一定的生物矿化及封闭作用,在治疗牙本质敏感方面存在潜在价值。

Objective：To evaluate the sealing ability of the 3.0th generation of polyamidoamine dendrimer（3.0 PAMAM）on hu-man dentinal tubules.Methods：1 6 extracted premolars were cut into 2 mm thick dentin slices to establish sensitive dentin model in vitro.Then 2 samples without any treatment were selected randomly into demineralized dentin group,and the remain 1 4 dentine pills were divided into 2 groups by the random number table（n=7）.Samples in the experimental group were treated with 3.0 PAMAM, those in the control group were treated with deionized water.After having immersed in the artificial saliva for 2 and 4 weeks respec-tively,the dentin slices were examined by scanning electron microscope（SEM）and X-ray energy dispersive spectroscopy（EDS）. Results：SEM showed that the minerals on the surfaces of the dentine disks in experimental group were formed gradually with the time,the dentinal tubules were blocked 4 weeks after treatment.The minerals on the sample surface in control group were less and the dentinal tubules remained open.EDS results showed that Ca/P（1 .49 ±0.1 6）of mineral deposition in the experimental group was higher than that in the control group （1 .1 8±0.20）（P〈0.05）.Conclusion：The 3.0th generation of PAMAMhas the occlu-ding ability by inducing remineralization on the dentine surface and it may be used in the treatment of dentin hypersensitivity.