上前牙美学牙冠延长术及术后修复

美学牙冠延长术通常以健康、舒适、美观为主要目的。为达到这个目的,必须作好详尽的术前检查,根据临床检查作出明确的诊断。手术应注意术前定位、考虑冠根比、判断牙齿断端与牙槽嵴顶的关系、采取合适的处理牙龈乳头的手术方法以及注意相邻牙齿的美观协调。术后的愈合与修复要掌握好时机,选择龈下边缘的修复类型时要慎重,防止破坏生物学宽度,修复体的设计要与患者的美学特点相协调。本文从临床操作的角度对以上问题作一综述。     

Histological changes in the temporomandibular joint in rabbits depending on the extent of mandibular lengthening by osteodistraction

We studied the histological changes in the temporomandibular joint (TMJ) after unilateral mandibular distraction osteogenesis in rabbits. Eight rabbits were used, two of which served as controls and the other six had distraction of the left mandibular body after a latency period of 7 days at a rate of 0.5mm a day for a total of 2mm (n = 2), 3.5mm (n = 2), and 5mm (n = 2) of distraction. After a 14-day consolidation period, TMJs from both sides were harvested and prepared for histological examination under an optical microscope using haematoxylin and eosin stain. We found no degenerative or inflammatory changes in either TMJ in any of the groups. Endochondral ossification in the condyle was greater on the opposite side in the experimental group than in the condyles of the control group. Endochondral ossification was active in the 3.5-mm group.     

Ilizarov技术治疗一侧先天性胫骨假关节并严重小腿短小畸形

目的 观察用Ilizarov技术治疗一侧先天性胫骨假关节(CPT)并肢体短小的远期临床效果.方法 对1例曾经5次手术治疗失败致胫骨严重缺损(9 cm)的患者,彻底清除病变部位病变软组织,保留病变骨段,应用Ilizarov技术在两断端开一凹凸骨槽进行嵌合加压,同时在胫骨近端骨骺下方截骨延长.结果 胫骨假关节骨性愈合,骨延长9 cm,延长骨段及假关节段骨完全修复,胫骨远端在未见骨骺线(骨骺破坏)的情况下可观察到长长,随访9 a,患肢胫骨与健肢等长、等大.结论 被侵蚀的骨组织(骨段)与纤维瘤病不属一类病变组织,一旦解除骨膜外的纤维瘤病病变软组织的包绕、压迫和侵蚀,病变骨就可复活再生;Ilizarov技术应用灵活,操作精确,适应证广,是治疗CPT及进行骨延长的理想方法.     

New treatment for peripheral nerve defects: Reconstruction of a 2 cm,monkey median nerve gap by direct lengthening of both nerve stumps

We have developed a new treatment for peripheral nerve defects: nerve‐lengthening method, and confirmed the efficacy and safety of our method using cynomolgus monkeys. A 20‐mm defect in the median nerve of monkey's forearms was repaired through the simultaneous lengthening of both nerve stumps with original nerve‐lengthening device. To evaluate nerve regeneration after neurorrhaphy, electrophysiological, histological, and functional recovery were examined and compared to the standard autografting. Nerve conduction velocity, axon maturation, and the result of functional test were superior in the nerve‐lengthening method than in the autografting. And there were no adverse events associated with our method. We concluded that this method is practical for clinical application. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:153–161, 2012     

Current concepts of leg lengthening

Any lower limb discrepancy may be equalised by conservative means (insoles, prosthesis and orthosis). However, their long-term acceptance is low in regard to function, costs, expenditure and appearance. Timely epiphysiodesis is the best option in uniplanar deformities with adequate remaining growth and for patients whose predicted final body height is above the 50th percentile. However, many patients present late or with multi-planar deformities, which warrant more sophisticated operative approaches. The history of surgical bone lengthening comprises 100 exciting years of struggling, development and ongoing learning. The initial strategy of acute or rapid incremental distraction had lasted almost half a century until Ilizarov recognised the benefits of biological periosteum-preserving osteotomies and incremental lengthening at slow rates (1 mm/day) at a 4 × 0.25-mm daily rhythm, well appreciated as callotasis. In parallel, ring and wire constructs made complex three-dimensional axial, translational and rotational bone moulding possible. Taylor Spatial Frames—built on hexapod strut-linked platform technology as known from flight simulators—took limb correction to a more reliable, more precise and aesthetical level, all the more that the whole process became web-based. It represents state-of-the-art methodology and technology for complex, multi-plane deformities. Due to the significant risk of secondary malalignment, indications for lengthening by unilateral fixation have shrunken to moderate amounts of length disparity and uni- to bi-planar deformities in patients with still open physes. Mechanical or motorised, minimally invasively placed nails prevent muscle fixation and, therefore, ease rehabilitation, increase patient comfort and potentially shorten the overall time of sick leave and refrain from sports activities. Hence, they offer a valuable alternative for low-grade complexity situations. It remains to be proved if the significantly higher implant costs are compensated by lower treatment costs. Overall, limb lengthening, particularly in combination with multi-planar deformity correction, can still be an arduous endeavour. In any case, wise judgement of the patient’s deformity, medical and biological situation, psychosocial environment, selection of the appropriate method and hardware, as well as meticulous operating technique by an experienced surgeon are the cornerstones of successful outcomes.     

低残面前牙龈下牙根保留修复方式的研究

目的通过对比研究低残面前牙龈下牙根保留修复的两种不同方式,为临床治疗方案的选择提供参考。方法对96名患者118颗低残面前牙龈下牙根进行桩核冠保留修复,A组(68颗)修复前利用残根冠延长术对残根进行处理,6周后进行常规铸造桩核及烤瓷冠修复。B组(50颗)修复前利用牙根移位术对残根进行处理,3个月后按照常规方法进行铸造桩核及烤瓷冠修复。对患者1年内的疗效进行评价。结果两种牙根处理术短期疗效均较好,3个月内未发现失败病例。6个月后牙齿修复效果在两组中均出现了不同程度的下降,失败率在牙冠延长术组及牙根移位术组的比率分别为2.56%及2%,至1年时,失败率增加为5.1%及6%。统计学比较分析结果显示,两组间的治疗效果差异无统计学意义(P﹥0.01)。结论两种处理方式本身对铸造桩核及烤瓷冠修复均具有很好的支持作用,进行口腔健康教育是良好修复效果的重要保障。     

Titanium Scaffolding: An Innovative Modality for Salvage of Failed First Ray Procedures

Shortening of the first ray is a potential complication associated with first metatarsal procedures. Correction of this deformity conventionally has required the use of a tricortical bone graft to lengthen the bone. Graft complications, including donor site morbidity, poor graft stability, and graft resorption, have revealed a need for an alternative procedure. The present report shows that titanium cage scaffolding has lower extremity applications beyond its previous uses in the ankle and spine. Two patients underwent surgical correction for failed first ray procedures using a titanium cage apparatus with a calcaneal autograft and other biologic agents. The scaffolds were appropriately sized to fill the defect. Patients remained non-weightbearing until radiographic evidence of healing appeared. Success was determined by diminished pain, a return to activity, ambulation, and patient satisfaction. Patients exhibited faster-than-anticipated healing, including a return to protected weightbearing activities and increased stability within 6 weeks. Titanium cage implants provide long-term stability and resistance to stress and strain in the forefoot. The implant we have described, newly applied to the first ray, is analogous to a system used in salvage of failed ankle replacements. In addition to reducing reliance on the iliac crest bone graft, the titanium cage apparatus is advantageous because it is customized to fill a defect using computed tomography scanning, thereby reducing graft failure secondary to an improper shape. These cases demonstrate the potential beneficial applications for titanium cages in failed first ray reconstruction.     

Late treatment of obstetrical brachial plexus palsy by humeral rotational osteotomy and lengthening with an intramedullary elongation nail

To date, all the authors who have recommended external rotation osteotomy (ERO) in the late treatment of obstetrical brachial plexus palsy (OBPP), have neglected upper limb length discrepancy, which is an another sequelae of OBPP. In this paper, a new technique is reported for the late treatment of OBPP patients with upper limb length discrepancy, in which both humeral external rotation osteotomy (ERO) and lengthening are applied with an intramedullary elongation nail. With this technique, upper limb function is improved through re-orientation of the shoulder arc to a more functional range, and further improvements will be seen in the appearance of the upper limb with the elimination of length discrepancy. It is also advocated that there is a potentiating effect of the humeral lengthening on shoulder movements gained by ERO when the osteotomy is applied above the deltoid insertion, as this allows more lateralized placement of the deltoid insertion.     

模拟牙冠延长术联合牙本质肩领设计对斜折残根抗折力的影响

目的研究模拟牙冠延长术联合不同高度牙本质肩领设计,对预成纤维桩核修复后的下颌第一前磨牙斜折残根抗折力的影响。 方法选择24颗完整离体下颌第一前磨牙,先于舌侧釉牙骨质界上2.0 mm处截冠成为水平型冠折残根,再自残根断面舌侧向颊侧斜行切割,制备舌唇向斜折残根模型。查随机数字表,将所有残根样本平均分为3组：A组在残根颈部预备颊侧0 mm、舌侧2.0 mm高的半包绕肩领（对照组）,B组和C组通过模拟牙冠延长术在残根颈部分别预备颊侧1.0、2.0 mm高的肩领,对应舌侧肩领高度分别为3.0和4.0 mm。经玻璃纤维桩核铸造金属全冠修复后,所有试样自铸造全冠颈缘完成线下2.0 mm包埋于自凝塑料块中。将试样以与牙长轴成135°放置于万能力学试验机上加载,直至试样发生折裂。记录试样断裂载荷,行单因素方差分析,对差异有显著性结果再行Tukey HSD Test分析（α= 0.05）。 结果A、B、C各组试样的折裂载荷均值依次为（1.01 ± 0.26）、（0.91 ± 0.29）、（0.73 ± 0.19）kN,牙本质肩领对纤维桩核冠修复后斜折残根抗力影响差异无统计学意义（F= 2.588,P= 0.099）。颊侧无肩领对照组的残根抗力最高,而随着根颈部肩领高度的增加,斜折残根的抗折力呈现逐渐下降的趋势。 结论通过模拟牙冠延长术在下颌第一前磨牙舌唇向斜折残根颈部预备1.0~ 2.0 mm完整肩领时,会降低残根的抗折力。     

牙冠延长术结合桩核冠修复保留不良修复体拆除后残根残冠长期疗效观察（附1例14年随访报告）

不良修复体的长期存在有损口腔健康,为长期健康地保留患牙,使之发挥正常的咀嚼功能,维护牙列完整,需要拆除不良修复体后接受多学科联合治疗。文章展示了1例不良修复体拆除后应用牙冠延长术结合桩核冠修复方法保留患牙使其行使功能并观察至今长达14年的病例,以期为临床中残根残冠的处置和长期保留提供思路。