Gao Yuan, Liang Kunneng, Li Jianshu, Yuan He, Liu Hongling, Duan Xiaolei, Li Jiyao
State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China.
Department of Operative Dentistry and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China.
Materials (Basel). 2017 Apr 5;10(4):384. doi: 10.3390/ma10040384.
In recent years, scientists have developed various biomaterials to remineralize human teeth to treat dentine hypersensitivity. Poly(amido amine) (PAMAM) dendrimers have become a research focus in this field. It has been demonstrated that PAMAM is able to create precipitates both on the surface of and within the dentinal tubules, however, there is little information about its effect on reducing dentine permeability in vitro. This study aimed to evaluate the in vitro effectiveness and stability of the fourth generation amine-terminated PAMAM on dentinal tubule occlusion, especially on dentine permeability. Sodium fluoride (NaF), which has been widely used as a desensitizing agent, is regarded as positive control. Demineralized sensitive dentine samples were coated with PAMAM or sodium fluoride solutions and soaked in artificial saliva (AS) at 37 °C for different periods. Four weeks later, samples in each group were then equally split into two subgroups for testing using a brushing challenge and an acid challenge. Dentine permeability of each specimen was measured before and after each challenge using a fluid filtration system. Dentine morphology and surface deposits were characterized by scanning electron microscope (SEM) and analyzed with Image-Pro Plus software. Data were evaluated through multifactorial ANOVA with repeated measures and pair-wise comparisons at a level of 5%. The results showed that PAMAM and NaF significantly reduced dentine permeability to 25.1% and 20.7%. Both of them created precipitates on dentine surfaces after AS immersion for 28 days. PAMAM-induced biomineralization not only on dentine surfaces, but also deeper in dentinal tubules, significantly reduced dentine permeability. Moreover, PAMAM-induced biomineralization elicited excellent stable occlusion effects after acid challenge. In conclusion, PAMAM demonstrated a strong ability to resist acid and showed great potential to be used in the treatment of dentine hypersensitivity in future.
近年来，科学家们已研发出多种生物材料来使人类牙齿再矿化，以治疗牙本质过敏症。聚（酰胺胺）（PAMAM）树枝状大分子已成为该领域的研究热点。已证明PAMAM能够在牙本质小管表面及内部形成沉淀，然而，关于其在体外降低牙本质渗透性方面的作用，相关信息较少。本研究旨在评估第四代氨基封端的PAMAM对牙本质小管封闭的体外有效性和稳定性，尤其是对牙本质渗透性的影响。已被广泛用作脱敏剂的氟化钠（NaF）被视为阳性对照。将脱矿的敏感牙本质样本用PAMAM或氟化钠溶液包被，并在37℃的人工唾液（AS）中浸泡不同时间。四周后，每组样本再平均分为两个亚组，分别通过刷牙挑战和酸挑战进行测试。在每次挑战前后，使用流体过滤系统测量每个样本的牙本质渗透性。通过扫描电子显微镜（SEM）对牙本质形态和表面沉积物进行表征，并使用Image-Pro Plus软件进行分析。数据通过重复测量的多因素方差分析和5%水平的两两比较进行评估。结果表明，PAMAM和NaF可将牙本质渗透性显著降低至25.1%和20.7%。在AS浸泡28天后，它们均可在牙本质表面形成沉淀。PAMAM诱导的生物矿化不仅发生在牙本质表面，还深入到牙本质小管中，显著降低了牙本质渗透性。此外，PAMAM诱导的生物矿化在酸挑战后产生了优异的稳定封闭效果。总之，PAMAM表现出强大的抗酸能力，在未来用于治疗牙本质过敏症方面具有巨大潜力。
