Effect of Surface Tooling Techniques of Medical Titanium Implants on Bacterial Biofilm Formation In Vitro

The aim of this study was to assess the biofilm formation of Streptococcus mutans, Staphylococcus aureus, Enterococcus faecalis, and Escherichia coli on titanium implants with CAD-CAM tooling techniques. Twenty specimens of titanium were studied: Titanium grade 2 tooled with a Planmeca CAD-CAM milling device (TiGrade 2), Ti₆Al₄V grade 5 as it comes from CAD-DMLS device (computer aided design-direct metal laser sintering device) (TiGrade 5), Ti₆Al₄V grade 23 as it comes from a CAD-CAM milling device (TiGrade 23), and CAD-DMLS TiGrade 5 polished with an abrasive disc (TiGrade 5 polished). Bacterial adhesion on the implants was completed with and without saliva treatment to mimic both extraoral and intraoral surgical methods of implant placement. Five specimens/implant types were used in the bacterial adhesion experiments. Autoclaved implant specimens were placed in petri plates and immersed in saliva solution for 30 min at room temperature and then washed 3× with 1× PBS. Bacterial suspensions of each strain were made and added to the specimens after saliva treatment. Biofilm was allowed to form for 24 h at 37 °C and the adhered bacteria was calculated. Tooling techniques had an insignificant effect on the bacterial adhesion by all the bacterial strains studied. However, there was a significant difference in biofilm formation between the saliva-treated and non-saliva-treated implants. Saliva contamination enhanced S. mutans, S. aureus, and E. faecalis adhesion in all material types studied. S. aureus was found to be the most adherent strain in the saliva-treated group, whereas E. coli was the most adherent strain in the non-saliva-treated group. In conclusion, CAD-CAM tooling techniques have little effect on bacterial adhesion. Saliva coating enhances the biofilm formation; therefore, saliva contamination of the implant must be minimized during implant placement. Further extensive studies are needed to evaluate the effects of surface treatments of the titanium implant on soft tissue response and to prevent the factors causing implant infection and failure.     

Electrochemical Evaluation of Stress Corrosion Cracking Susceptibility of Ti-6Al-3Nb-2Zr-1Mo Alloy Welded Joint in Simulated Deep-Sea Environment

Titanium alloys have high specific strength and excellent corrosion resistance and have been applied in deep-sea engineering fields. However, stress corrosion cracking may become one of the biggest threats to the service safety of a high-strength titanium alloy, as well as its weldment. In this work, stress corrosion cracking of a gas-tungsten-arc-welded Ti-6Al-3Nb-2Zr-1Mo (Ti6321) alloy influenced by the applied potentials in simulated deep-sea and shallow-sea environments was investigated by combining slow strain rate testing with electrochemical measurements. The results showed that the service environment and applied potential have a substantial effect on the stress corrosion cracking behavior of the Ti6321 welded joint. The Ti6321 welded joint exhibited higher stress corrosion susceptibility in a simulated deep-sea environment and at a strong polarization level owing to the diminishing protection of the passive film under passivation inhibition and the enhancement of the hydrogen effect. The fracture of a Ti6321 welded joint in the weld material could be attributed to the softening effect of the thick secondary α within the coarse-grained martensite. The electrochemical evaluation model of stress corrosion cracking susceptibility of a Ti6321 welded joint in a simulated marine environment was established by adding the criterion in the passivation region based on the literature model, and four potential regions corresponding to different stress corrosion cracking mechanisms were classified and discussed. Our study provides useful guidance for the deep-sea engineering applications of Ti6321 alloys and a rapid assessment method of stress corrosion risk.     

化学气相淀积反应器中超细粒子的形态控制 Ⅲ.TiO_2超细粒子晶体组成

在超细粒子粒度及粒度分布控制模型的基础上,对快相变速率和慢相变速率两种晶型转变情形,建立了化学气相淀积合成超细粒子过程中,表征超细粒子晶体组成及含量的物理模型和数学模型。利用该模型探讨了物系参数和操作参数对超细粒子晶体组成的影响,理论预测和实验结果相一致。     

腹腔镜骶骨阴道固定术治疗重度子宫脱垂

目的：探讨腹腔镜骶骨阴道固定术治疗重度子宫脱垂的临床疗效。方法2011年1月～2013年4月对22例POP-Q分期Ⅲ、Ⅳ期的重度子宫或阴道穹隆脱垂患者行腹腔镜下“Y”形聚丙烯网片骶骨阴道固定术,合并阴道前、后壁膨出者分别于膀胱阴道间隙和直肠阴道间隙增加植入网片的长度,合并中度以上压力性尿失禁（ stress urinary incontinence ,SUI）者同期行经闭孔无张力尿道中段吊带术（transobturator tension-free vaginal tape, TVT-O）,采用POP-Q分期法和盆底功能障碍性疾病症状问卷-20（PFDI-20）、盆底疾病生活质量影响问卷短表-7（PFIQ-7）、盆腔器官脱垂/尿失禁性生活质量问卷-12（PISQ-12）分别评价解剖和功能疗效。结果22例均成功完成手术,1例因合并重度SUI同期行TVT-O,术中未发生膀胱、输尿管、直肠他大血管损伤。手术时间（134．3±36．6）min,术中出血量（77．3±37．8）ml,术后2～3 d拔尿管均能自主排尿,无尿潴留。22例术后随访（17．5±8．2）月,无手术失败及术后复发,无网片侵蚀、暴露;POP-Q分期Aa、Ba、C、Ap、Bp各指示点解剖位置中位数由术前1．5、3．0、2．0、-2．3、-1．5 cm分别恢复为术后-3．0、-3．0、-8．0、-3．0、-3．0 cm。 PFIQ-7、PFDI-20评分中位数由术前66．7、66．2分恢复为术后12．0、14．6分,PISQ-12评分由术前（69．4±10.3）分提高到（86．9±10．0）分（t＝12．351,P＝0．000）;UDI-6术前后无改善（Z＝-0．337,P＝0．736）。术后新发SUI 3例,急迫性尿失禁1例。术前6例尿失禁,术后2例症状减轻,4例症状加重,其中1例术后8个月行 TVT-O,3例功能锻炼并观察。患者主观满意度为95．4％（21/22）。结论腹腔镜骶骨阴道固定术是治疗重度子宫或穹隆脱垂的一种安全、有效的方法,但有诱发或加重尿失禁的风险。     

椎间融合器治疗腰椎滑脱症临床观察

目的：观察螺纹状椎间融合器(Threaded Fusion Coge,TFC)治疗不稳定性腰椎滑脱的临床疗效。观察TFC对腰椎前凸的影响。方法：1997年11月-2000年3月，31例经过保守治疗无效的腰椎滑脱患者。接受手术治疗。31例中L4-518例，L5S113例。按Meyerding分类大于Ⅰ度滑脱2例，其余均在Ⅰ度以内，患者行后路椎管减压，同时单间隙置入2枚螺纹状椎间融合器（TFC），观察术前，术后和随访期间Taillard指数，Boxall指数，腰骶关节角，椎间高度指数的变化，观察矢状面脊柱序列的变化，结果：29例患者3月内症状显著减轻，随访期间病情稳定，症状没有复发，术前，术后和随访期间Taillard指数，Boxall指数没有变化，术后腰骶关节角增加，并且随访期间没有丢失，手术后椎间隙高度增加1倍，随访期间维持到增加50%。31例获得随访22例。优18例，良3例，一般1例；优良率95.5%。结论：椎间融合器治疗Ⅰ度腰椎滑脱症进行椎体间融合早期获得良好的临床治愈率，并发症低，椎间高度指数是定量分析椎间隙高度的一种方法。     

疝环充填式与平片式无张力疝修补术治疗腹股沟疝的临床比较研究

目的：比较疝环充填式与平片式无张力疝修补术治疗成人腹股沟疝的临床疗效。方法：随机将135例腹股沟疝病人分为疝环充填式组和平片式组，分析比较两组的临床及随访资料。结果：两组在手术时间，术后早期疼痛，导尿率，体温，并发症，平均住院日及术后复发率等方面无明显差异。结论：疝环充填式与平片式无张力疝修补术治疗成人腹股沟疝总的治疗效果相近。     

腰骶椎前路融合笼的设计及临床应用

目的　研制出腰骶椎前路融合笼 (AnteriorFusingCage-AFC)并选定相应的放置方式用于下腰痛患者的治疗。 方法　1、通过在人尸椎骨及牛椎骨标本上的生物力学试验 ,人尸椎骨的解剖学测量 ,结合手术要求 ,设计了AFC及相应辅助器械 ,并筛选出相应的放置方式。 2、将该技术用于 14例下腰痛患者的治疗。结果　 1、AFC直径≈ 1/ 2 (a +p) +12～ 16 (mm) ,AFC长度≈S - 6 -S×滑脱百分比。 2、放置方式为在L5S1间隙取正中 1枚AFC放置法及L4.5间隙取左前外斜向 1枚AFC放置法。 3、随访 2 4～ 4 5个月 ,初步结果满意。结论　AFC有助于施术节段的融合与稳定 ,增加椎间隙高度 ,不需术后长时间石膏外固定 ,该技术较国外同类方法简便安全     

Preliminary experience with new bioactive prosthetic material for repair of hernias in infected fields

Surgisis (Cook Surgical, Bloomington, Ind., USA) is a new four-ply bioactive, prosthetic mesh for hernia repair derived from porcine small-intestinal submucosa. It is a naturally occurring extracellular matrix which is easily absorbed, supports early and abundant new vessel growth, and serves as a template for the constructive remodeling of many tissues. As such, we believe that Surgisis mesh is ideal for use in contaminated or potentially contaminated fields in which ventral, incisional, or inguinal hernia repairs are required. From November 2000 through May 2002, 25 patients (11 male, 14 female) underwent placement of Surgisis mesh for a variety of different hernia repairs. A total of 25 hernia repairs were performed in our patient population. Fourteen procedures (56%) were performed in a potentially contaminated setting (i.e. with incarcerated/strangulated bowel within the hernia or coincident with a laparoscopic cholecystectomy/colectomy). Eleven repairs (44%) were performed in a grossly contaminated field, including one in which an infected polypropylene mesh from a previous inguinal hernia repair was replaced with Surgisis and one in which necrotic bowel was discovered within the hernial sac. Median follow-up was 15 months with a range of 1–20 months. Of the 25 total repairs, there was one wound infection complicated by enterocutaneous fistula in a patient originally operated on for ischemic bowel. The fistula was in a location independent of the Surgisis mesh. There were no mesh-related complications or recurrent hernias in our early postoperative follow-up period. Surgisis mesh appears to be a promising new prosthetic material for hernia repair, especially in contaminated or potentially contaminated fields. Obviously, long-term follow-up is still required. Electronic Publication     

Open mesh versus non-mesh repair of groin hernia meta-analysis of randomized trials leased on individual patient data

Abstract Background. The EU Hernia Trialists Collaboration was established to provide reliable evaluation of newer methods of groin hernia repair. It involved 70 investigators in 20 countries. Materials and methods. Twenty eligible trials (5016 participants) of open mesh vs. non-mesh groin hernia repair were identified. Meta-analysis was performed using raw individual patient data where possible. Results. Fewer hernia recurrences were reported after mesh repair. There were no clear differences between mesh and non-mesh groups in complications. Overall, those in the mesh groups had a shorter hospital stay, quicker return to usual activities and less frequent persisting pain, but individual trial results varied. Conclusions. The review provides strong evidence that open mesh repair is associated with a reduction in the risk of recurrence of between 50% and 75%. There is also some evidence of quicker recovery and of lower rates of persisting pain following open mesh repair. Electronic Publication     

Entero-colocutaneous fistula: a late consequence of polypropylene mesh abdominal wall repair: case report and review of the literature

Background. The underlying risk associated with visceral mesh erosion is the close opposition of adjacent intestines to the prosthetic graft. This highly morbid condition has been described with most types and techniques of abdominal wall mesh repair. Patient. We report the case of a 52-year-old man who presented with an entero-colocutaneous fistula 10 years after prosthetic mesh repair of an incisional hernia. The fistula was excised and the abdominal wall defect repaired with a tissue-impervious composite. Conclusions. The use of a tissue-impervious barrier avoids development of enteric fistula when a prosthesis is placed directly over the viscera. Electronic Publication