【作者】 刘芳；

【导师】 李雅娟； 陈树国；

【作者基本信息】 河北医科大学 ， 口腔临床医学， 2009， 硕士

【摘要】 目的:通过对HBIC型钛种植体与口腔科常用修复烤瓷合金在中性人工唾液、酸性及含氟的人工唾液中的电化学腐蚀性能进行综合评价,为临床合理选择与种植体相匹配的种植义齿上部结构材料提供参考。方法:(1)试件的制备选择目前本院使用的HBIC型钛种植体(T-H)以及临床常用冠修复材料:镍铬合金(N)、钴铬合金(C)、金铂合金(Au)、铸造纯钛(T),按厂家要求包埋铸造。所有试样均为直径4mm,高10mm的圆柱体,每种金属各4个。将金属圆柱体楔入直径为3.5mm的聚四氟乙烯管中,环氧树脂密封,一端导线接出。暴露面表面积为0.1257cm2。用220目、400目、600目、800目水砂纸顺序磨平,按临床抛光顺序和要求抛光,浸入人工唾液中24h备用,使表面状态趋于稳定。(2)人工唾液的制备配制pH=6.8;pH=4;pH=6.8加入0.1%F-; pH=4加入0.1%F-的A,B,C,D四种人工唾液。(3)采用经典三电极体系的电化学方法,在A,B,C,D四种人工唾液中检测5种常用牙科金属(合金)以及HBIC型钛种植体(T-H)的自腐蚀电位(E corr)、腐蚀电流密度(Iccor),并绘制出极化曲线。(4)扫描电镜对合金表面形貌进行观察。结果:1五种不同金属在四种人工唾液中的自腐蚀电位1.1在pH=6.8的人工唾液中Au>C>N>T>T-H,其中Au组的自腐蚀电位大于其余四组金属(合金)的自腐蚀电位(p<0.05),C组、N组的自腐蚀电位大于T组、T-H组(p<0.05),C组、N组与T组、T-H组间无统计学意义(p>0.05)。1.2 T组、T-H组在A、B、C、D四种不同人工唾液的自腐蚀电位依次为A<B<C<D,其中在人工唾液C、D中的自腐蚀电位大于在人工唾液A、B中的自腐蚀电位,有统计学差异(p<0.05),在人工唾液C、D中的自腐蚀电位也有统计学差异(p<0.05),在人工唾液A、B中的自腐蚀电位没有统计学差异(p>0.05)。2同种材料在不同介质中的腐蚀电流密度(μA/cm2)2.1金铂合金组在四种人工唾液中测得腐蚀电流密(Iccor)依次为AuA组<AuC组< AuB组<AuD组;在人工唾液B、D中测得腐蚀电流密度大于在人工唾液A、C中的腐蚀电流密度,有统计学差异(p<0.05),AuC与AuA组间, AuB组和AuD组间无统计学差异(P>0.05)。2.2镍铬合金组在A,B,C,D四种人工唾液处理后测得腐蚀电流密度(Iccor)以此为NA组<NC组<NB组<ND组;在人工唾液B、D中测得腐蚀电流密度大于在人工唾液A、C中的腐蚀电流,有统计学差异(p<0.05),NB组小于ND组,有统计学差异(p<0.05) ,NC与NA组和NB组间无统计学差异(P>0.05)。2.3钴铬合金组在A,B,C,D四种人工唾液中测得腐蚀电流密度(Iccor)为CC组<CA组< CB组<CD组,在人工唾液A、B、C,中测得腐蚀电流密度小于在人工唾液D中的腐蚀电流密度,有统计学差异(p<0.05),其余三组间无统计学差异(P>0.05)。2.4铸造纯钛组在四种人工唾液中测得腐蚀电流密(Iccor)依次为TA组< TC组<TB组<TD组;在人工唾液A、B、C,中测得腐蚀电流密度小于在人工唾液D中的腐蚀电流密度,有统计学差异(p<0.05)。TA组、TB组、TC组间无统计学差异。2.5 HBIC型钛种植体组在四种人工唾液测得腐蚀电流密度(Iccor)依次T-HA组< T-HB组<T-HC组<T-HD组;在四种不同人工唾液中测得腐蚀电流密度T-HD组大于T-HA组、T-HB组、T-HC组,有统计学差异(p<0.05)。T-HA组、T-HB组、T-HC组间无统计学差异(p>0.05)。3不同种材料在同一介质中的腐蚀电流密度(μA/cm2)3.1在pH=6.8的人工唾液中,四种金属腐蚀电流密度(Iccor)为依次为N组>C组>T组> T-H组>Au组,其中N组、C组与Au组、T组、T-H组间有统计学差异(p<0.05),N组与C组,T组与T-H组与Au组间无统计学差异(p>0.05);在pH=4的人工唾液中四种金属腐蚀电流密度(Iccor)为依次为N组>C组>Au组> T组> T-H组,其中T组、T-H组与N组、C组、Au组间有统计学差异(p<0.05),Au组Iccor小于N组与C组有统计学差异(p<0.05) ,T组与T-H组,N组与C组间无统计学差异(p>0.05)。3.2在pH=6.8的含0.1%F-人工唾液中,五种金属腐蚀电流密度(Iccor)没有统计学差异(p>0.05)。在pH=4的含0.1%F-人工唾液中AuD组<CD组<ND组<TD组< T-HD组,其中AuD组与CD组、ND组、TD组、T-HD组间,ND组、CD组与TD组、T-HD组间,N D组与CD组间有统计学差异(p<0.05),TD组与T-HD组间无统计学差异(p>0.05)。4扫描电镜观察,金合金在pH=6.8、pH=6.8含氟人工唾液中测试后在扫描电镜下观察未见明显腐蚀破坏;在pH=4和pH=4含氟人工唾液中测试后合金表面可见散在的且直径较小的浅的点蚀坑;镍铬合金在pH=6.8、pH=6.8含氟人工唾液中腐蚀明显,为典型的孔蚀样表现,且随pH降低,腐蚀加剧;钴铬合金在pH=6.8、pH=4及pH=6.8含氟的人工唾液中测试后扫描电镜下观察有剥脱性腐蚀破坏表现,在酸性含氟环境中腐蚀破坏加剧;铸造纯钛、HBIC型钛种植体在pH=6.8、pH4及pH=6.8加0.1% F的人工唾液中的腐蚀均不明显,但在pH=4加0.1% F的人工唾液中测试后扫描电镜高倍下观察表现为蜂窝状改变,金属原有形态完全破坏。结论:1在中性人工唾液中,金铂合金、镍铬合金、钴铬合金、铸造纯钛及HBIC型钛种植体均有较好的耐腐蚀性能,其中金合金、铸造纯钛及HBIC型钛种植体耐腐蚀性优于钴铬合金、镍铬合金。2在酸性人工唾液中镍铬合金、金合金腐蚀电流密度明显增大,而pH值的降低对钴铬合金、铸造纯钛及HBIC型钛种植体没有明显影响。3氟化物的加入使金合金、钴铬合金、镍铬合金、铸造纯钛及HBIC型钛种植体在酸性人工唾液中的腐蚀电流密度均呈增大趋势,其中铸造纯钛及HBIC型钛种植体对酸性环境氟化物敏感性更大,腐蚀电流与中性人工唾液相比有明显差别。4在酸性环境以及酸性含氟环境中会加剧种植体及冠材料电化学腐蚀的进行,经常进行种植体及牙周维护,降低菌斑形成,有助于维持唾液pH在正常范围;使用氟制剂时,若调整氟制剂的pH值为碱性或中性,有助于减弱修复烤瓷合金电化学腐蚀程度。更多还原

【Abstract】 Objective: The purpose of this study was to evaluate the corrosion behavior of HBIC-Ti implant and Au-Pt alloy, Ni-Cr alloy, Co-Cr alloy,casting pure Ti in artificial saliva with different pH and fluoride contents.it was usefud for references and basis for selecting suprastructure in dental implantation dental alloys in the clinic.Methods:1 Preparation of alloys specimens: HBIC-Ti implant(Ti-HBIC) of commonly used dental alloys : Ni-Cr alloys (N), Co-Cr alloy(C), casting pure Ti(T) are selected.Each type of alloy was cast into 4 samples under the manufacture instruction ,all samples were shaped into a cylindrical form, in order to constitute the cap of a rotating disk electrode. With4mm diameter , 10mm high , cylinders were wedged into PTFE pipage with 3.5mm diameter,the exposed surfase of metal is 0.1275mm2. All the samples were ground and polished as follows: the specimens were subjected to waterproof abrasive paper on 220, 400, 600, 800 grit silicon carbide then immerse into artificial saliva for 24 h.2 The preparation of the artificial saliva : Four different artificial saliva: pH6.8(A), pH 4(B), pH6.8with0.1%F-(C) ,pH 4 with0.1%F-(D).3 In A, B, C, D artificial saliva at 37±0.5℃, the corrosion potential(E corr), corrosion current density (Iccor) and polarizaion curve of there usual dental the materials,which were Ni-Cr alloy, Co-Cr alloy, casting pure titanium and HBIC-Ti implant, were tested by the classic three electrodes system of electrochemical method.4 Surface analysis by SEM.Results:1 The corrosion potential (Ecorr) of different materials in the different artificial saliva.Tab-31.1 Ecorr of five different metals in the artificial saliva A were Au>C>N>T>T-HBIC, Ecorr Au was bigger than other four kind of metals(p<0.05), Ecorr N, Ecorr C were bigger than Ecorr T, Ecorr T-H(p<0.05),There were no signifcant difference between Ecorr N and Ecorr C, Ecorr T and EcorrT-H, (p>0.05).1.2 Ecorr of Tgroup and T-Hgroup in the artificial saliva A,B,C,D were EcorrA <Ecorr B<Ecorr C<EcorrD, The corrosion potential in the the artificial saliva C、D were bigger than that in the the artificial salivaA、B(p<0.05),There was significant differece between Ecorr C and EcorrD(p<0.05), There was no significant differece between Ecorr A and EcorrB(p<0.05)2 The corrosion current density of same materials in the different artificial saliva (IccorμA /cm2)2.1 Aurum- platinum alloy The corrosion current density of Au-Pt alloy tesed by A, B, C, D artificial saliva respectively were AuA <AuC < AuB <AuD, The corrosion current density tested in artificial saliva B and D exceed tested in artificial saliva A and C, there is significant diffreence (p<0.05),but there is no significant diffreence in the corrosion current density tested in artificial saliva between C and D, and Iccor tested in artificial saliva between Aand B(P>0.05).2.2 Nickel-chromium alloy The corrosion current density of Ni-Cr alloy tesed by A, B, C, D artificial saliva respectively were The corrosion current density tested in artificial saliva B and D exceed tested in artificial saliva A and C, there is significant diffreence (p<0.05),but there is no significant diffreence in the corrosion current density tested in artificial saliva between C and D, and Iccor tested in artificial saliva between Aand B(P>0.05).2.3 Cobalt-chromium alloy The corrosion current density of Co-Cr alloy tesed by A, B, C, D artificial saliva respectively wereCC<CA< CB<CD, The corrosion current density tested in artificial saliva A, B, C is smaller than Iccor tested in artificial saliva D, there is significant diffreence (p<0.05), Iccor among other there kind artificial saliva were no significant difference (P>0.05).2.4 Casting pure titanium The corrosion current density of Casting pure Ti tesed by A, B, C, D artificial saliva respectively were TA< TC<TB<TD, The corrosion current density tested in artificial saliva A, B, C is smaller than Iccor tested in artificial saliva D, there is significant diffreence (p<0.05), Iccor among other there kind artificial saliva were no significant diffreence(P>0.05).2.5 HBIC-Ti implant The corrosion current density of HBIC -Ti tesed by A, B, C, D artificial saliva respectively were T-HA< T-HB<T-HC<T-HD, The corrosion current density tested in artificial saliva A, B, C is smaller than Iccor tested in artificial saliva D, there is significant diffreence (p<0.05), Iccor among other there kind artificial saliva were no significant difference (P>0.05).3 The corrosion current density of different materials in the same artificial saliva (IccorμA /cm2)3.1 In the artificial saliva A the corrosion current density of five metals respectively were N>C> T> T-H>Au, The corrosion current density tested of Au group and T group, T-H group was smaller than that N group and C group , there was significant difference (p<0.05). but there was no significant difference in the corrosion current density between N group and C group, among Au group ,T group and T-H group (P>0.05). In the artificial saliva B the corrosion current density of five metals respectively were N>C>Au>T>T-H, The corrosion current density tested of T group, T-H group was smaller than that of Au group, N group and C group, Au group was smaller than that of N group and C group ,there were significant difference (p<0.05). but there was no significant difference in the corrosion current density between N group and C group, T group ,and T-H group (P>0.05). 3.2 In the artificial saliva C, The corrosion current density tested of five kind of metals were no significant difference(p>0.05), In the artificial saliva D, the corrosion current density was AuD group<CD group<ND group <TD group< T-HD group, there was significant between AuD group and other four groups,N group and C group(p<0.05),The corrosion current density tested of N group, C group were smaller than T group and T-H group, there was significant difference (p<0.05), but there was no significant difference between T group and T-H group (P>0.05).4 Surface analysis by SEM:4.1 Au-Pt alloy: No obvious corrosion was observed on the surface of Au-Pt alloy tested in artificial saliva A and C, but in artificial saliva B and D there was some small sporadic shallow corrosion spot.4.2 Ni-Cr alloy: there was obvious corrosion of Ni-Cr alloy tested in artificial saliva A and C, It was typical pitting appeara- -nce,and pH degrade intensified the alloy corrosion.4.3 Co-Cr alloy: Exfoliatus destroy was observed on the surface of Co-Cr alloy tested in four different artificial saliva , and pH degrade intensified the alloy corrosion.4.4 Casting pure Ti and Ti-HBIC implant: There were both no obvious corrosion on the surface of two type of Ti tested in art -ificial saliva A,Band C, but in the artificial saliva D honeyc -omb appearance was observed in high power, the inhere appearance of metal was destroyed completely. Conclusion:1 In the neutral artificial saliva, the corrosion current density of Ni-Cr alloys, Co-Cr alloy, casting pure Ti, HBIC-Ti implant all smaller than 10-6, five kind of materials had a good corrosion resistance, but Au-Pt alloy and pure Ti presented the better corrosion resistance, and were far superior to that of Ni-Cr alloy and Co-Cr alloy.2 The corrosion current density of Ni-Cr alloys and Au-Pt alloy increased significantly, but Co-Cr alloy, casting pure Ti, HBIC-Ti implant was free of influnce.3 Adsition of F- in the acidic artificial saliva promoted the corrosion current density of five metals, casting pure Ti, HBIC-Ti implant were more sensitive than other alloys.there was a signifcant difference with that in pH=6.8 artificial saliva.4 Decreacing of pH and adsition of F- in the acidic artificial saliva intensified the electrochemical corrosion of implant and crown material, so removal bacterial plaque to maintain pH at normal limits and adjusting fluorine praeparatum to alkalinity or neutrality would be good to decreace the electrochemical corrosion.更多还原