个体化钛支架在构筑颌骨三维形态中的应用

目的　在运用快速成型技术制作的颌骨模型上作成个体化钛支架 ,以构筑颌骨三维形态。方法　 18例颌骨缺损患者进行个体化钛支架联合游离组织瓣修复重建。其中 10例上颌骨缺损以钛网支架重建上颌骨前壁、外侧及底壁 ,如内侧壁缺损则一并恢复 ,其口鼻创面以前臂皮瓣或串联腓骨肌瓣修复 ;8例下颌骨缺损以钛板支架塑形 ,联合游离腓骨 ,精确恢复下颌骨外形及髁突生理位置。结果　所有的病例随访 6～ 12个月 ,除 1例于术后9个月眶外侧壁复发外 ,其余未见肿瘤复发。皮瓣除 2例因术后放疗部分坏死外全部成活。所有患者面部外形均非常满意 ,张口度 2 .5～ 4cm ,正常进食。上颌骨重建病人无口鼻瘘 ,语音较为清晰 ,下颌髁突均在正常解剖生理位置 ,面部软组织亦很对称。结论　个体化钛支架应用于颌骨重建 ,能够较为精确地恢复颌骨外形 ,有利于术中引导移植骨准确对位 ,可避免术后的继发功能障碍 ,有效节省手术时间 ,其在复杂颅颌面疾病诊治中的应用前景非常乐观。     

TiO2 nanotubes improve physico-mechanical properties of glass ionomer cement

ObjectivesThe aim of this study was to determine the physico-mechanical properties of a high viscosity glass ionomer cement (GIC) reinforced with TiO₂ nanotubes (TiO₂-nt).MethodsTiO₂-nt was incorporated into the GIC powder components (Ketac Molar EasyMix™) in concentrations of 0% (control group), 3%, 5%, 7% by weight. Compressive strength (n = 10/group), three point bending for flexural strength (n = 18/group), microshear bond strength to dentin and failure mode (n = 20/group), and surface roughness and weight loss before and after brushing simulation (30,000 cycles) (n = 8/group) were evaluated. Data were submitted to Shapiro-Wilk, ANOVA, Tukey and Chi-square tests (α ≤ 0.05).ResultsAddition of 5% of TiO₂-nt into GIC presented the highest values for compressive strength and differed from the control, 3% and 7% groups (p = 0.023). There were no significant differences in flexural strength (p = 0.107) and surface roughness before and after the dental brushing (p = 0.287) among the groups. GIC added with 5% TiO₂-nt showed the lowest weight loss values (p = 0.01), whereas the control, 3% or 5% TiO₂-nt groups presented similar microshear bond strength values (p ≥ 0.05). The 5% TiO₂-nt group featured higher microshear bond strength than the 7% TiO₂-nt group (p = 0.034). Cohesive in material was the most representative failure mode for all groups.SignificanceThe incorporation of TiO₂-nt did not affect GIC’s adhesiveness to dentin, but improved its compressive strength at 5%. Furthermore, TiO₂-nt decreased the percentage of weight loss after GIC’s surface wear.     

纯钛表面微弧氧化结合Ⅰ型胶原对成骨细胞黏附增殖的影响

目的 探讨微弧氧化(microarc oxidation,MAO)结合应用于纯钛种植体表面处理的可行性.方法 根据对纯钛钛片处理的不同将实验分为对照组(A组,不作处理)、MAO组(B组,纯钛片上进行MAO处理)及MAO加Ⅰ型胶原组(C组,纯钛片上MAO处理后吸附Ⅰ型胶原).将成骨细胞培养于各组钛片上,通过扫描电镜、MT...     

电泳沉积多孔钙镁硅生物玻璃陶瓷涂层

目的电泳沉积法制备出钛合金/钙镁硅生物玻璃陶瓷涂层复合材料,优化制备工艺条件。方法用溶胶-凝胶法制备出钙镁硅生物玻璃陶瓷粉体,通过粉体在不同分散介质中的带电特性和沉积结果,筛选合适的溶剂;通过改变悬浮液陈化时间(10分钟、1小时、24小时)、悬浮液体系固含量(0.02kg/L、0.06kg/L、0.12kg/L)、电压(20V、40V、80V)及钛合金基底的预处理方法,观察不同条件对电泳沉积涂层表面形貌和性能的影响,找出较佳的制备条件。结果生物玻璃陶瓷粉体在乙醇中带正电荷,且能在钛合金阴极基底上均匀沉积;在经过机械打磨的钛合金表面沉积的涂层均匀无裂纹,而未经打磨的钛合金表面的涂层开裂严重;悬浮液的固含量为0.02kg/L,陈化时间在10分钟时为最佳分散条件;沉积电压为20V、40V、80V均能制备出均匀无裂纹的涂层,经过煅烧后的涂层为多孔结构,涂层厚度为10~250 m,XRD结果显示涂层是以透辉石,镁黄长石等为主晶相的玻璃陶瓷。结论经过条件优化,可以制备出均匀无开裂的多孔生物玻璃陶瓷涂层,涂层厚度和致密度可控。     

Surface roughness mediates its effects on osteoblasts via protein kinase A and phospholipase A2

Earlier studies have shown that implant surface roughness influences osteoblast proliferation, differentiation, matrix synthesis and local factor production. Moreover, the responsiveness of osteoblasts to systemic hormones, such as 1,25-(OH)₂D₃, at the implant surface is also influenced by surface roughness and this effect is mediated by changes in prostaglandins. At present, it is not known which signaling pathways are involved in mediating cell response to surface roughness and how 1,25-(OH)₂D₃ treatment alters the activation of these pathways. This paper reviews a series of studies that have addressed this question. MG63 osteoblast-like cells were cultured on commercially pure titanium (cpTi) surfaces of two different roughnesses (R_a 0.54 and 4.92 μm) in the presence of control media or media containing 1,25-(OH)₂D₃ or 1,25-(OH)₂D₃ plus H8 (a protein kinase A inhibitor) or quinacrine (a phospholipase A₂ inhibitor). At harvest, the effect of these treatments on cell number and alkaline phosphatase specific activity was measured. Compared to cultures grown on the smooth surface, cell number was reduced on the rough surface. 1,25-(OH)₂D₃ inhibited cell number on both surfaces and inhibition of protein kinase A in the presence of 1,25-(OH)₂D₃ restored cell number to that seen in the control cultures. Inhibition of phospholipase A₂ in the presence of 1,25-(OH)₂D₃ caused a further reduction in cell number on the smooth surface, and partially reversed the inhibitory effects of 1,25-(OH)₂D₃ on the rough surface. Alkaline phosphatase specific activity was increased in cultures grown on the rough surface compared with those grown on the smooth surface; 1,25-(OH)₂D₃ treatment increased enzyme specific activity on both surfaces. Cultures treated with H8 and 1,25-(OH)₂D₃ displayed enzyme specific activity that approximated that seen in control cultures. Inhibition of phospholipase A₂ also inhibited the 1,25-(OH)₂D₃-dependent effect on the smooth surface, but on the rough surface there was an inhibition of the 1,25-(OH)₂D₃ effect as well as a partial inhibition of the surface roughness-dependent effect. The results indicate that surface roughness and 1,25-(OH)₂D₃ mediate their effects through phospholipase A₂, which catalyzes one of the rate-limiting steps in prostaglandin E₂ production. Further downstream, prostaglandin E₂ activates protein kinase A.     

Deformation-induced ω phase in modified Ti–29Nb–13Ta–4.6Zr alloy by Cr addition

For spinal-fixation applications, implants should have a high Young’s modulus to reduce springback during operations, though a low Young’s modulus is required to prevent stress shielding for patients after surgeries. In the present study, Ti–29Nb–13Ta–4.6Zr alloy (TNTZ) with a low Young’s modulus was modified by adding Cr to obtain a higher deformation-induced Young’s modulus in order to satisfy these contradictory requirements. Two newly designed alloys, TNTZ–8Ti–2Cr and TNTZ–16Ti–4Cr, possess more stable β phases than TNTZ. These alloys consist of single β phases and exhibit relatively low Young’s moduli of <65 GPa after solution treatment. However, after cold rolling, they exhibit higher Young’s moduli owing to a deformation-induced ω-phase transformation. These modified TNTZ alloys show significantly less springback than the original TNTZ alloy based on tensile and bending loading–unloading tests. Thus, the Cr-added TNTZ alloys are beneficial for spinal-fixation applications.     

门诊内镜治疗小儿结肠息肉的临床探讨

目的探讨门诊内镜下高频电凝切除术联合钛夹、尼龙圈套治疗小儿结肠息肉的临床疗效、安全性及并发症的防治。方法回顾分析采用内镜下高频电凝切除术联合钛夹、尼龙圈套治疗的190例患儿的临床资料,其中门诊患儿105例,住院患儿85例,对两组患儿行内镜下治疗,治疗后观察1周,以后分别于术后第3个月、第6个月进行一次随访。结果190例患儿的225枚肠息肉经内镜下全部成功切除,无大出血、穿孔及息肉切除术后综合征,其中门诊2例患儿及住院1例患儿在术后7d内出现少量渗血,经内镜下治疗后缓解,两组患儿的临床疗效、安全性及并发症发生率无统计学意义（P〉0．05）,门诊治疗费明显较住院治疗少。结论高频电凝切除术联合钛夹、尼龙圈套是门诊治疗小儿结肠息肉的一种安全可靠的方法。     

医用钛缆环扎加"8"字张力带内固定在髌骨骨折治疗中的应用

目的 探讨医用钛缆张力带在髌骨骨折中的应用价值.方法 2009年10月至2012年12月102例髌骨骨折,均遵循张力带原则,行环扎加"8"字张力带内固定术治疗,根据内固定材料分成医用钛缆组和带针钢丝组.比较两组术后首次锻炼时间、住院时间、医疗费用、并发症及远期膝关节功能情况.结果 102例患者术后随访10周~8个月,末次随访时骨折均达骨性愈合标准.两组患者在术后首次锻炼时间、住院时间方面无明显差异.医用钛缆组费用较高.医用钛缆组在并发症及远期膝关节功能上优于带针钢丝组.结论 医用钛缆在行张力带内固定治疗髌骨骨折具有内固定坚强、便于术后早期功能锻炼,弥补带针钢丝内固定强度不足的缺点.     

钛网植骨联合颈前路钢板内固定术治疗颈椎病的临床护理

颈前路减压植骨融合术已广泛应用于颈椎伤病的手术治疗,并取得了显著疗效.但由于需要取自体髂骨,供骨区感染、骨折、慢性疼痛等并发症的发病率高达10％～30％[1-2].我院2007年5月～2010年5月应用钛网植骨联合颈前路钢板内固定治疗颈椎病32例,取得了满意的效果,现将我们对该手术的临床护理总结如下.