Feasibility of Eucommia ulmoides gum as a root canal filling material

doi:10.3969/j.issn.2095-4344.2015.16.010

Abstract

Abstract:

BACKGROUND: Eucommia ulmoides gum has good thermoplastics, liquidity, bondability and antimicrobial properties. However, the application of Eucommia ulmoides gum as a root canal filling material is rarely reported.
OBJECTIVE: To compare the different contents of gas phase nano-silica on mechanical performance of composite material taking the gutta-percha as the matrix, and observe the effect of the root canal filling.
METHODS: Four kind of root canal filling materials were prepared through adding barium sulfate (20%), nano-hydroxyapatite (10%) and different contents of gutta-percha and gas phase nano-silica (40% and 15%, 45% and 20%, 50% and 25%, 55% and 30%). Pure Eucommia ulmoides gum served as the blank control. The mechanical properties (hardness, tensile strength and rupture elongation rate) of those five materials were detected. Furthermore, four kinds of composite materials, pure Eucommia ulmoides gum and Gutta-Percha Pellets were filled into the fresh extracted premolar root canal by using Obtura II technology. The effect of root canal filling was observed under X-ray and scanning electron microscopy.
RESULTS AND CONCLUSION: Along with the increase of the content of gas phase nano-silica, the hardness of Eucommia ulmoides gum composite material increased, tensile strength increased firstly and then decreased, and rupture elongation rate decreased. Pure Eucommia ulmoides gum was transmitted to the X-ray and no image of filling material was obtained. Four kinds of composite materials were resistant to X-ray, and images showed that all composite materials were equally filled into the root canal, without cacuole, and were in contact with the root canal inner wall, showing good filling effect. Scanning electron microscopy showed that, fingerlike projections were the longest at the surface of pure Eucommia ulmoides gum; as the content of gas phase nano-silica increased, fingerlike projection length reduced at the surface of composite materials. Eucommia ulmoides gum composite materials could be developed as a canal filling material under heat flow condition.

中国组织工程研究杂志出版内容重点：生物材料；骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性；组织工程

全文链接：

Key words: Gutta-Percha, Silicon Dioxide, Molar

CLC Number:

R318

Long Hui, Zhang Feng-y, Feng Yun-zhi . Feasibility of Eucommia ulmoides gum as a root canal filling material[J]. Chinese Journal of Tissue Engineering Research, 2015, 19(16): 2511-2517.

Figures/Tables 4

材料约2 mm厚，呈黑色固体，表面光滑平整、质稍硬，有一定的弹性。图1为杜仲胶复合材料制成哑铃形的试样图。 2.2 杜仲胶复合材料的机械强度杜仲胶复合材料的硬度：A0-A4组材料的邵氏D硬度分别为(43.240±0.979)，(49.320±1.583)，(49.960±1.305)，(51.220±2.516)，(53.640±2.696)度。气相纳米二氧化硅含量不同时，各组的硬度走势见图2所示。各组间的比较见表2所示，添加了气相纳米二氧化硅的各组(A1、A2、A3、A4)与杜仲胶组(A0)之间的硬度值比较差异有显著性意义(P < 0.05)，A1、A2、A3之间比较差异无显著性意义(P > 0.05)，A3、A4之间比较差异无显著性意义(P > 0.05)，A4与A1、A2之间比较差异有显著性意义(P < 0.05)。从复合材料硬度走势图(图2)来看，随着气相纳米二氧化硅含量的增加，杜仲胶复合材料的邵氏D硬度呈现出增加的趋势。杜仲胶复合材料的拉伸强度：用微机控制电子拉力试验机按GB/T 528-2009的标准测量得到A0-A4组材料的拉伸强度分别为(7.367±0.737)，(11.060±0.230)，(11.060± 0.611)，(6.367±0.451)，(5.600±0.612) MPa。气相纳米二氧化硅含量不同时，各组材料的拉伸强度走势见图3所示，各组间比较见表3所示，添加了气相纳米二氧化硅的各组(A1、A2、A3、A4)与杜仲胶组(A0)之间的拉伸强度比较差异有显著性意义(P < 0.05)，A1、A2之间比较差异无显著性意义(P > 0.05)，A3、A4之间比较差异无显著性意义(P > 0.05)，A1与A3、A4之间、A2与A3、A4之间比较差异有显著性意义(P < 0.05)。从统计学分析结果及拉伸强度走势图来看，随着气相纳米二氧化硅含量的增加，杜仲胶复合材料的拉伸强度呈现出先增加后降低的趋势。拉伸强度最高出现在气相纳米二氧化硅含量在15%(A1)、20%(A2)的2组，含量再增高呈现出急剧下降的趋势。杜仲胶复合材料的断裂伸长率：用微机控制电子拉力试验机按GB/T 528-2009的标准测量得到A0-A4组材料的断裂伸长率分别为(20.467±2.231)%，(2.180± 0.512)%，(1.780±0.915)%，(1.580±0.709)%，(0.960±0.351)%。气相纳米二氧化硅含量不同时，各组断裂伸长率走势见图4所示，各间的比较见表4所示，添加了气相纳米二氧化硅的各组(A1、A2、A3、A4)与杜仲胶组(A0)之间的断裂伸长率比较差异有显著性意义(P < 0.05)，A1、A2、A3、A4之间比较差异无显著性意义(P > 0.05)。从统计学分析结果及拉伸强度走势图来看，随着气相纳米二氧化硅含量的增加，杜仲胶复合材料的断裂伸长率呈现出下降的趋势，且杜仲胶组(A0)与其他各实验组之间差异十分明显。 2.3 杜仲胶复合材料的根管充填效果杜仲胶复合材料行根管充填后的X射线观察(图5)：杜仲胶组(A0)对X射线透射，因此X射线片上显示不出来充填材料的影像。添加了无机填料的各杜仲胶实验组(A1、A2、A3、A4)均具有一定的X射线阻射性，根管充填效果可以在X射线片上显示出来，4组杜仲胶复合材料均充填至根管中且充填均匀，充填物内无气泡，与根管内壁接触良好，充填效果满意。杜仲胶复合材料行充填后的扫描电镜观察(图6)：各组行根管充填后从颊舌向沿根管长轴纵形劈开根管，纵劈后肉眼观察可见充填物均匀完整，表面无气泡，与根管形态吻合。由于根管充填物相较于牙根的纵劈平面来说是呈突出的圆弧状，因此扫描电镜无法直观清晰地看到根管充填物伸入到牙本质小管的情况，但可从根管充填物表面的与牙本质小管吻合的指状突起的高度、密度、均质性等反映出杜仲胶复合材料渗入牙本质小管的情况。①B0组：Obtura180 ℃古塔胶颗粒根管充填材料表面指状突起较多，分布均匀，突起大部分呈圆柱状，亦有呈圆锥状，但圆锥状较少见，充填物与牙本质交界处呈拉扯状，突起长度4-8 µm不等。②A0组(杜仲胶组)：材料表面指状突起最多最长，较为密集地突出于材料上且突起之间均匀，突起的直径基本相等，长度为8-15 µm不等，平均12 µm。③A1组：复合材料表面指状突起较多，分布较均匀，突起大多数呈圆柱状，少部分呈圆锥状，突起的长度不一致呈弯曲状，短的约3 µm，长的可达约8 µm。④A2组：复合材料表面指状突起较多，且分布均匀，突起普遍呈圆柱状，突起长度基本一致，约8 µm，突起较短的区域较少，此区域突起的根部直径稍大，整体分布仍均匀。⑤A3组：复合材料表面指状突起欠均匀，突起的长度大小不等，短的突起约3 µm，长的突起可达8 µm，有的突起呈圆锥状，尖端直径小于根部直径。⑥A4组：复合材料表面可见丘疹样突起，突起较均匀，但长度较短，仅2.0-3.0 µm。"

References

[1] 付文,刘安华,王丽.杜仲胶的提取与应用研究进展[J].弹性体, 2014,24(5):76-80.
[2] 王凤菊.杜仲胶的战略价值不容置疑[J].中国橡胶,2014,30(8): 9-10.
[3] 李春霞,辛振祥,夏琳.天然杜仲橡胶在橡塑方面的研究进展[J].特种橡胶制品,2014,49(1):78-80.
[4] 刘继潭.新型高分子材料杜仲胶的应用研究[J].现代商贸工业, 2012,25(4):291.
[5] Hu W,Wang G,Li P,et al.Neuroprotective effects of macranthoin G from Eucommia ulmoides against hydrogen peroxide-induced apoptosis in PC12 cells via inhibiting NF-κB activation.Chem Biol Interact.2014;224C:108-116.
[6] 严瑞芳.论杜仲胶的研究开发[C].张康健.中国杜仲研究.西安:陕西科技出版社,1992:19-23.
[7] 刘世会.杜仲蛋白纯化、序列分析及抗菌活性研究[D].贵州:贵州大学,2008.
[8] 赵德刚,韩玉珍,傅永福.杜仲胶生物合成相关蛋白质的研究[J].中国农业大学学报,1999,4(1):114.
[9] Tsai TH,Tsai TH,Chien YC,et al.In vitro antimicrobial activities against cariogenic strepto-cocci and their antioxidant capacities: A comparative study of green tea versus different herbs.Food Chemistry.2008;110(4):859-864.
[10] 严瑞芳.杜仲胶研究进展及发展前景[J].化学进展,1995,7(1): 65-71.
[11] Vanni JR,Della-Bona A,Figueiredo JA,et al.Radiographic evaluation of furcal perforations sealed with different materials in dogs' teeth.J Appl Oral Sci.2011;19(4):421-425.
[12] 严瑞芳,薛兆弘.中国:881037427[P],1988-06-24.
[13] 范彦博,周妍,刘大鹏,等.杜仲主要化学成分分类总结[J].中国药师,2014,17(10):1756-1759.
[14] 袁带秀,舒丽霞,黄荣.杜仲总黄酮对荷瘤小鼠的抗肿瘤作用[J].中国临床药理学与治疗学,2014,19(12):1332-1336.
[15] 崔永锋,张永斌,李刚,等.杜仲对兔骨折愈合影响的光镜观察实验研究[J].中国比较医学杂志,2005,15(3):154-156.
[16] 赵德刚,韩玉珍,傅永福.杜仲胶生物合成相关蛋白质的研究[J].中国农业大学学报,1999,4(1):114.
[17] Tsai TH,Tsai TH,Wu WH,et al.In vitro antimicrobial and anti-inflammatory effects of herbs against Propionibacterium acnes.Food Chemistry.2010;119(3):964-968.
[18] Tsai TH,Chien YC.In vitro antimicrobial activities against cariogenic streptococci and their antioxidant capacities: A comparative study of green tea versus different herbs.Food Chemistry.2008;110:859-864.
[19] 张晗.聚乙烯/硫酸钡纳米复合材料的制备和表征[D].天津:天津理工大学,2012.
[20] 王雪林,赵志刚,薛兆弘等.填料对杜仲橡胶结晶性能的影响[J].橡胶工业,1999,46(10):583-586.
[21] 杨海堃.超微细气相法白炭黑的表面改性[J].化工新型材料,1999, 27(10):8-12.
[22] 顾书英,刘玲玲,高偰峰，等.纳米复合形状记忆聚合物[J].高分子通报,2014,27(9):1-9.
[23] 王鹏义,谢伟丽,郭英姿,等.纳米SiO2对笼形低聚硅倍半氧烷复合树脂硬度和耐摩擦性的影响[J].现代口腔医学杂志,2014, 28(6):348-350.
[24] 张盼.纳米二氧化硅的研究与应用[J].印刷质量与标准化,2014, 22(1):18-21.
[25] 康文涛,岳红,沙青娥,等.NR/CIIR/TPI共混物相容性及力学性能的分子动力学模拟[J].粘接,2014,35(4):68-72.
[26] 张鹏宇,王娜,戴采云,等.纳米二氧化硅粒径对橡胶复合材料力学性能的影响[J].功能材料,2014,45(23):23086-23090.
[27] 王继虎,陈大俊,杨涛,等.二氧化硅改性凹凸棒土/天然橡胶复合材料的研究[J].非金属矿,2014,36(6):8-10.
[28] 刘杰胜,木子佳靓,余荆城,等.二氧化硅填料与硅橡胶基胶相互作用研究[J].武汉工业学院学报,2013,32(4):27-31.
[29] Talwar N,Chand P,Sinqh BP,et al.Evaluation of the Efficacy of a Prosthodo-ntic Stent in Determining the Position of Dental Implants.J Prosthodont.2012;21(1):42-47.
[30] Yim JH,Ryu DM,Lee BS,et al.Analysis of digitalized panorama and cone beam computed tomographic image distortion for the diagnosis of dental implant surgery.J Craniofac Surg. 2011;22(2):669-673.
[31] 黄超,陈克南,宋倩.下颌前牙牙根及根管变异的研究现况[J].牙体牙髓牙周病学杂志,2014,24(11):673-676.
[32] Oliveira MA,Venâncio JF,Raposo LH,et al.Morphometric evaluation and planning of anticurvature filing in roots of maxillary and mandibular molars.Braz Oral Res.2015;29(1): 1-9.
[33] Bonavilla J D,Bush M A,Bush P J,et al.Identification of incinerated root canal filling materials after exposure to high heat incineration.J Forensic Sci. 2008;53(2):412-418.
[34] 付文,刘安华,李建雄.反式1,4-聚异戊二烯弹性体的应用研究进展[J].橡胶工业,2013,60(7):440.