Fracture of the femur after knee arthroplasty

The supracondylar fracture of the femur is a serious complication after total knee arthroplasty. We report our experience in the management of 16 patients with this complication and suggest that the main line of treatment should be conservative. Open reduction and plate fixation is precarious. In displaced fractures, however, the Rush pin technique was useful.     

多层螺旋CT后处理技术在下颌骨骨折中的应用

目的分析多层螺旋CT(Multi-slice Spiral CT,MSCT)后处理技术在下颌骨骨折中的应用及临床价值。方法 26例下颌骨骨折病人行MSCT扫描,图像经工作站处理后进行多平面重建(multi-planarreconst ruction,MPR)、表面遮盖显示(shaded surface display,SSD)及容积再现(volume rendering,VR)三维重建。由两位副高职称以上放射科CT室医师共同阅片分析,统一评定,并与普通X线片检查结果进行比较。结果本组26例均可以通过MSCT后处理技术明确判断骨折情况,普通X线片漏诊6例,经统计学分析两者差异有显著性意义(X2=6.783,P=0.009,P0.05)。结论 MSCT后处理技术能清晰、直观地显示下颌骨骨折情况,减少漏诊、误诊,有利于临床诊断及治疗方案的确定。     

第一二鳃弓综合征的综合手术治疗

目的探讨第一二鳃弓综合征的综合治疗手段,以期为临床提供一种较短疗程且实用有效的手术方法。方法对小耳畸形伴同侧面部严重发育不良的第一二鳃弓综合征患者,用传统方法取自体肋软骨支架进行分期耳郭再造的同时,再用自体肋骨塑形分别填充同侧颧弓及下颌骨,纠正耳颌畸形,重塑面部轮廓。结果5例患者术后随访3～7个月,面形丰满,立体感强,双侧面部基本对称,肋骨及肋软骨支架未见变形、吸收、外露等并发症。结论此方法设计合理,操作简便,效果满意,并发症少,为治疗第一二鳃弓畸形的有效方法之一。     

Marginal bone loss around implants retaining hinging mandibular overdentures, at 4-, 8- and 12-years follow-up

AIM: The aim of the present study was to study the effect of occlusal factors, oral hygiene, gender and age on the long-term maintenance of alveolar bone height around screw-shaped machined surface commercially pure (c.p.) titanium implants retaining hinging mandibular overdentures. METHOD: In this retrospective study a long-term (4-, 8-, up to 12-years) follow-up of such implant-retained overdentures was performed. From the population of patients so treated at the University Hospital of the Catholic University Leuven, Department of Periodontology and Department of Prosthetic Dentistry, 158 patients were selected on the basis of being treated before March 1994, and the availability of intra-oral radiographs (paralleling technique) present at abutment connection (baseline) and at years 4, 8, and 12. For each patient, all relevant clinical data were recorded, and measurements of marginal bone height around the implants were performed on intra-oral radiographs by means of a digital sliding caliper. RESULTS: Results indicated that only the factor "time" had a significant influence on marginal bone loss. The age and gender of the patients, dental/prosthetic status in the antagonistic jaw, oral hygiene variables, and location of the implants had no significant effect. CONCLUSION: The very high cumulative success rate (97.2%) and limited marginal bone loss (on average 1.7 mm) after 12-years, encourage this kind of treatment using this type of implants.     

下颌骨外侧中弧线的研究

本文对95例中国成年男女下颌骨的“下颌骨外侧中弧线”若干点进行测量、描记和曲线直线化处理。结果表明:该线大致为一条抛物线。线性回归法得相关系数r≥0.95,计算曲线经验公式Y=KX~2的系数,男性0.0286±0.0007、女性0.03055±0.0005。此线与“下颌骨外侧下弧线”和“下颌骨外侧上弧线”的K值比较有显著差异(P<0.05)。     

中性区技术在义齿制作中的应用

中性区技术能帮助提高全口义齿，特别是下颌义齿的稳定性，尤其适用于牙槽嵴严重吸收患者全口义齿的制作，但国内尚未广泛应用。本文通过报道1例采用此种技术制作义齿的病例，介绍中性区技术，并改良了利用发音塑形的方法，结合文献对中性区技术在国内临床的应用进行讨论。     

下颌双侧低位近中阻生第三磨牙微创与传统拔除的对照研究

目的 :通过同体对照方法 ,比较微创法与传统凿骨劈冠法拔除下颌低位近中阻生第三磨牙的临床效果。方法:2012—2015年,在浦东新区人民医院口腔科就诊,需拔除双侧下颌低位近中阻生智齿的患者120例。随机分为2组,第1组一侧第三磨牙首先采用微创拔牙技术拔除(研究组),另一侧采用凿骨劈冠法拔除(对照组),两次操作间隔3个月。第2组拔牙方法的顺序相反,先用凿骨劈冠法拔除一侧第三磨牙(对照组),3月后采用微创拔牙法拔除另一侧(研究组)。对两种拔牙方法患者的拔牙时间、术中并发症、术后并发症、患者满意度、牙科畏惧率等进行比较观测和统计学分析。结果:研究组的拔牙时间、术中并发症、术后并发症、畏惧率明显较对照组低,两组间差距有统计学意义;且研究组患者满意度高,两组间差距有统计学意义。结论:运用微创拔牙技术拔除下颌低位阻生智齿,临床效果优于传统的凿骨劈冠法。     

软食对青春期大鼠下颌后牙区牙槽骨微结构的影响

目的 :观察软食喂养引起的机械负荷改变对青春发育期大鼠下颌后牙区牙槽骨微结构的影响。方法 :取16 d龄雄性SD大鼠20只,随机分为软食组(SD组)和硬食组(HD组),每组各10只。7周后,运用显微CT(Micro CT)技术观察分析2组大鼠下颌第一磨牙(M1)区牙槽骨的松质骨微结构,苏木精-伊红染色对脱钙后的下颌骨M1区域进行组织学观察。结果:Micro-CT结果显示,较HD组而言,SD组M1区松质骨的骨小梁厚度(Tb.Th)显著减少(P<0.01),骨小梁间距(Tb.Sp)显著升高(P<0.05);组织学结果显示,SD组M1牙槽纵隔以及根尖区域骨小梁较HD组稀疏、变细,骨髓腔增大,近牙周韧带区域骨细胞分布减少。结论:软食喂养引起的负荷降低减少了下颌后牙的牙槽骨骨小梁的厚度、增加了骨小梁间距,从而影响了其骨微结构。     

Osseointegrated Titanium Implants: Requirements for Ensuring a Long-Lasting, Direct Bone-to-Implant Anchorage in Man

A total of 2895 threaded, cylindrical titanium implants have been inserted into the mandible or the maxilla and 124 similar implants have been installed in the tibial, temporal or iliac bones in man for various bone restorative procedures. The titanium screws were implanted without the use of cement, using a meticulous technique aiming at osseointegration-a direct contact between living bone and implant. Thirty-eight stable and integrated screws were removed for various reasons from 18 patients. The interface zone between bone and implant was investigated using X-rays, SEM, TEM and histology. The SEM study showed a very close spatial relationship between titanium and bone. The pattern of the anchorage of collagen filaments to titanium appeared to be similar to that of Sharpey's fibres to bone. No wear products were seen in the bone or soft tissues in spite of implant loading times up to 90 months. The soft tissues were also closely adhered to the titanium implant, thereby forming a biological seal, preventing microorganism infiltration along the implant. The implants in many cases had been allowed to permanently penetrate the gingiva and skin. This caused no adverse tissue effects. An intact bone-implant interface was analyzed by TEM, revealing a direct bone-to-implant interface contact also at the electron microscopic level, thereby suggesting the possibility of a direct chemical bonding between bone and titanium. It is concluded that the technique of osseointegration is a reliable type of cement-free bone anchorage for permanent prosthetic tissue substitutes. At present, this technique is being tried in clinical joint reconstruction. In order to achieve and to maintain such a direct contact between living bone and implant, threaded, unalloyed titanium screws of defined finish and geometry were inserted using a delicate surgical technique and were allowed to heal in situ, without loading, for a period of at least 3-4 months.     

Fructooligosaccharide consumption improves the decreased dentin formation and mandibular defects following gastrectomy in rats

OBJECTIVE: We examined the effects of fructooligosaccharides (FOS) consumption on gastrectomy-evoked osteopenia and disorders of dentin formation in rats. MATERIALS AND METHODS: Male Sprague-Dawley rats (n = 28, 35-day old) were equally divided into two groups; sham-operated and gastrectomized, and sham-operation or total gastrectomy was performed. Four weeks after each surgery, the rats were divided into two sub-groups (n = 7 each); with or without 7.5% FOS-feeding for 6 weeks. Backscattered electron images of the mandibular sections were taken to calculate trabecular bone area, cortical bone area and total scan area. Thereafter, the dentin formation rate in maxilla were calculated using a fluorescent microscope. RESULTS: Trabecular bone area and cortical bone area in GX rats were markedly decreased. FOS-feeding significantly counteracted this reduction, but not to the level seen in sham-operated rats. Total scan area in gastrectomized groups was significantly decreased. The dentin formation rate was not statistically different among the groups, except the gastrectomized group. CONCLUSION: These results suggest that FOS consumption partially restored osteopenia and almost completely restored the reduction in dentin formation following gastrectomy in rats.