牵张成骨术在延长下颌骨中新骨生成方式的研究

目的　探讨山羊下颌骨牵张成骨过程中新骨生成方式及其影响因素。方法　用口外牵张器 ,按1mm/天的牵张速率将 12只成年山羊的双侧下颌骨延长 10 m m,牵张结束后固定至第 2、4和 8周分别处死 4只动物 ,拍摄下颌骨 X线片后取牵张区新生骨痂作组织学观察。结果　牵张间隙内新骨组织沿牵张方向向心性生长 ,成骨方式主要是膜内成骨 ,在牵张器松动的标本早期仍可观察到散在的软骨岛。结论　牵张延长下颌骨过程中新骨生成方式主要为膜内成骨 ,软骨化骨只是在牵张器固定不良时发生。     

CT evaluation of regenerated osseous segments following bone transport

Abstract A morphological analysis using radiography and computed tomography was performed in a total of 17 bone segments following single or double bone transport in 11 and 3 patients, respectively. All bone transports involved the tibia, with the exception of 2 single bone transports, which were femoral. The following parameters were measured: cortical wall thickness, sectional area of the medullary canal, and density of the cortical bone and medullary canal in Hounsfield units (HU). The regenerated segments showed a cortical thickness and density that were less than the contralateral portion, with an enlargement of the medullary canal and an increase in density due to the presence of cancellous bone in the medullary area. Successive controls showed an increase in thickness and density of the cortical bone and a small reduction in the diameter of the medullary canal and its cancellous bone. The variations in the cortical and the medullary canal appeared to be independent of the length of the regenerated segment. In the 3 tibia treated by double bone transport, the anatomical variations in the distal regenerated portion varied less from normal values than the proximal portion of the same segment. In the 2 femurs examined, enlargement of the regenerated section was smaller with respect to cases involving regeneration of the proximal tibia. These differences are presumably dependent on the fact that in the latter case, a more vascularized segment is produced after osteotomy in spongy bone, with respect to those involving the distal tibia or femur. Double transport is preferable due to the reduced treatment times.     

The ultrasound scan in monitoring regenerated bone

The aim of this work was to delimit the diagnostic possibilities of the ultrasound scan in the evaluation of regenerated bone produced in bone lengthenings and transports. The study is based on 56 ultrasound scans of regenerated bone regarding 4 lengthenings and 18 bone transports. X-ray examinations were taken in 13 patients contemporarily with the ultrasound scans and a comparative and qualitative evaluation between the radiographic gap and the ultrasound one was made. The ultrasound scans allowed us to distinguish 3 kinds of regenerated bone: normal, cystic and hypertrophic. In 7 cases, at the proximal third of the tibia, a cyst in the regenerated bone was noticed on ultrasonography. The evaluation of these cysts after the slowing down of the distraction speed was satisfactory in the sense that they disappeared in the following examinations, their volume did not change and they did not interact with the following maturation and corticalization of the regenerated bone. In one case, at the proximal third of the tibia, we noticed two cysts that disappeared after regenerated bone compression while, after a new distraction made at a lower speed, a cyst appeared again maintaining its unchanged volume. The presence of one or more cysts indicates an initial crisis of the regenerated bone which could develop into a dangerous hypotrophy if the distraction speed remained unchanged. In 5 cases with a hypertrophic regenerated bone, a gap less than 10 mm was noticed. It was treated by accelerating the distraction speed. The ultrasound examination can offer a precise monitoring of distractional osteogenesis. Received: 27 November 2001, Accepted: 4 April 2002 Correspondence to: C. Iacobellis     

Distraction osteogenesis for bone repair in the 21st century: lessons learned

Bone regeneration obtained by distraction osteogenesis is influenced by a series of factors. These include factors that are related to the mechanical stability of the system of distraction (internal or external devices), and to factors directly depending on the biology of the bone tissue, such as the method of bone interruption (osteotomy), the delay and rhythm of distraction, the anatomical site of the osteotomy, and the histological characteristics of the bone requiring reconstruction. The stability of the system of bone fixation depends on the rigidity of the frame, the connexion of the apparatus to the bone (wires, pins) and the intrinsic stability of the segment (length and level of maturation of bone regenerate). The radiological characteristics of bone regeneration (hypo- or hypertrophy) lead to the adaptation of the rhythm of distraction. Following more than 28 years of experience of application of the Ilizarov method for bone reconstruction, the authors describe the technique of frame assembly and the methods of evaluation and treatment of the complications of new bone formation.     

Rh-BMP-2 in distraction osteogenesis: Dose effect and premature consolidation

We asked whether locally applied recombinant-bone morphogenic protein-2 (rh-BMP-2) with a type I collagen carrier could enhance the consolidation phase in distraction osteogenesis and whether a dose effect could be reported. We performed unilateral transverse osteotomy of the tibia in 15 immature male rabbits. In Group I (five rabbits), 750 μg of rh-BMP-2 on the type I collagen sponge (Inductos^®, Medtronic) was locally applied on the day of osteotomy; the Group II animals (five rabbits) received 375 μg of the drug and the Group III (control group, five rabbits) had no local application. After 7 days, 3 weeks of distraction was begun at a rate of 0.5 mm/12 h. Starting week 2 of distraction, we assessed radiographic, ultrasonographic, and densitometric parameters once per week. Animals were sacrificed after a 3-week consolidation period. Radiographic evaluation revealed increased regenerate ossification in the rh-BMP-2 groups compared with the control group. The bone mineral content was significantly higher in the rh-BMP-2 treated groups at each time point. A dose effect is shown as densitometric parameters were significantly higher between Groups I and II. 3/5 of the Group I treated animals developed a premature bony union in the regenerate resulting in premature fusion and incomplete distraction.     

Intermittent parathyroid hormone (1-34) enhances mechanical strength and density of new bone after distraction osteogenesis in rats.

Distraction osteogenesis is used both for leg lengthening and for bone transportation in the treatment of fractures and nonunions. The main problem with this method is that the time until full recovery may be up to a year, partly because of the time needed for the new formed bone to consolidate and become strong enough for weight bearing. We have studied whether intermittent parathyroid hormone (PTH(1-34)) could accelerate the consolidation of new formed bone after distraction osteogenesis in rats. Forty-seven, 3-months-old male Sprague-Dawley rats underwent lengthening of the right femur using an external fixator. After a middiaphyseal osteotomy and a 7-day latency period, the callus was distracted during 10 days, with a distraction rate of 0.25 mm twice a day. The consolidation time was either 20 days or 40 days after distraction was completed. A dose of 60 microg of human PTH(1-34)/kg body weight/injection or vehicle was given every second day beginning 30 days before the rats were killed. Both femura of each rat were subjected to mechanical testing and dual-energy X-ray absorptiometry. Blinded histological examination was done for the distracted femura. In the 20 days consolidation experiment, PTH(1-34) increased ultimate load (56%), stiffness (117%), total regenerate callus volume (58%), callus BMC (24%) and histologic bone density (35%) compared to untreated distraction osteogenesis specimens. In the 40 days consolidation experiment, PTH(1-34) increased ultimate load (54%), stiffness (55%), callus BMC (33%) and histologic bone density (23%) compared to untreated distraction osteogenesis specimens. Total regenerate callus volume was unchanged. The contralateral femur also became stronger, stiffer and denser under PTH(1-34) treatment, but to a lesser degree. PTH(1-34) might become useful to shorten the consolidation time after distraction osteogenesis in humans.     

富血小板血浆和脱钙骨基质促进牵拉成骨矿化过程的实验研究

目的观察局部植入富血小板血浆(platelet-rich plasma,PRP)复合脱钙骨基质(decalcified bone matrix,DBM)是否具有协同作用加速牵拉成骨矿化过程,促进骨愈合。方法健康雄性新西兰大白兔40只,体重2.2～2.8 kg,随机分为4组,每组10只。于兔耳中央动脉取血采用Landesberg法制备PRP。于兔左胫骨胫腓关节下制备1 cm骨缺损模型。A组为对照组,行牵拉成骨1 cm;B组:植入0.5 cm长DBM并牵拉成骨0.5 cm;C组:牵拉成骨1 cm加局部注射PRP 1 mL;D组:植入0.5 cm长复合1 mL PRP的DBM并牵拉成骨0.5 cm。术后7 d开始延长,每天2次,每次0.5 mm;A、C组延长10 d,B、D组延长5 d。延长结束后进入矿化期。术后0、12、17、27、37 d摄X线片观察新生骨矿化过程;术后37 d处死实验动物,完整切取胫骨行Micro-CT扫描及三维重建,并进行生物力学测试。结果 X线片观察示术后37 d内B、C组新生骨生成情况明显优于A、D组。B、C组新生骨的骨矿物质密度(bone mineral density,BMD)、骨矿物质含量(bone mineral content,BMC)和骨体积分数(bone volume fraction,BVF)均显著高于A、D组(P<0.05);C组BMC、BMD显著高于B组(P<0.05),B、C组间BVF差异无统计学意义(P>0.05);A、D组间BMD、BMC及BVF比较差异无统计学意义(P>0.05)。C组骨小梁数量(trabecula number,Tb.N)明显多于其余各组,骨小梁间隔(trabecula spacing,Tb.Sp)小于其余各组(P<0.05);其余各组间Tb.N和Tb.Sp比较差异均无统计学意义(P>0.05)。各组骨小梁厚度比较,差异均无统计学意义(P>0.05)。生物力学测试显示,各组极限角位移比较差异均无统计学意义(P>0.05)。B、C组最大扭矩明显大于A、D组,C组大于B组,差异均有统计学意义(P<0.05);A、D组间差异无统计学意义(P>0.05)。结论 局部注射PRP可促进牵拉成骨矿化过程,加速骨缺损愈合;在正常牵拉速度下,DBM可促进牵拉成骨矿化过程;但在牵拉成骨早期植入复合PRP的DBM并未进一步加速矿化促进骨愈合。     

延长成骨术修复颅骨缺损的实验研究

目的探讨以延长成骨修复颅骨缺损的可行性。方法随机挑选1岁龄山羊17只,分为A、B、C三组,A组7只,于顶骨处左右各形成一大小相等面积为3.0 cm×2.2 cm矩形骨缺损;B组5只,于顶骨处右侧形成一2.2 cm×2.2 cm的正方形骨缺损;C组5只,于顶骨处左右各形成一大小为3 cm×1 cm矩形骨缺损。各组于右侧骨缺损形成相应的转移骨瓣并安放延长器,A组三维CT对修复颅骨面积进行测量;B组行成骨后生物力学测量;C组行组织学染色、扫描电镜、透射电镜检查观察成骨过程。结果A组可见实验侧骨缺损大部分逐渐被延长成骨所修复,剩余少量骨缺损与自身对照有统计学意义(P<0.01),B组实验侧与正常对照侧无统计学意义,C组观察成骨过程,为典型的膜内成骨。结论延长成骨术是一种可行的修复颅骨缺损的方法。     

Changes in blood perfusion and bone healing induced by nicotine during distraction osteogenesis

Nicotine is the main chemical in cigarettes responsible for the tobacco's pathological effects. The influence of nicotine on bone healing remains controversial. Distraction osteogenesis provides an ideal model to study bone healing and regeneration. The present study aims to evaluate the effects of nicotine on blood perfusion, angiogenesis and bone formation using a rabbit model of mandibular lengthening. Twenty adult New Zealand white rabbits were randomly assigned to the control group and nicotine group. The total nicotine or placebo exposure time for all animals was 7 weeks. After 2- or 4-week of consolidation following osteotomy, 3-day of latency and 11-day of active distraction, the animals were sacrificed and the mandibles were harvested. Blood perfusion and vascularization were evaluated by Laser Doppler monitoring and Collagen IV immunohistochemistry staining respectively. Bone formation was assessed by radiological, histological and immunohistochemical examination. Results showed that nicotine exposure increased microvessel density, whereas inhibited blood flow and bone formation. The expression of bone morphogenetic protein (BMP)-2 in osteoblasts was also decreased. Frequent appearance of cartilage islands suggested ischemia and low oxygen tension in the distraction regenerate. We concluded that nicotine compromises bone regeneration possibly by causing ischemia and directly inhibitory effect on osteoblastic cells. Nicotine exposure enhances angiogenesis but cannot compensate for the adverse effect of vasoconstriction.     

Combined effects of recombinant human BMP-2 and Nell-1 on bone regeneration in rapid distraction osteogenesis of rabbit tibia

Distraction osteogenesis (DO) has been accepted as an effective technique for bone lengthening. However, the long treatment period and possible fibrous union or nonunion hampers its further clinical application. Bone regeneration in DO involves multiple stages of repair and coordinated action of multiple cell types. Consequently, it may be possible to enhance bone regeneration through treatment strategies that target more than one repair process or cell types. The goal of this study was to determine the combined effects of recombinant human bone morephogenetic protein 2 (rhBMP-2) and NEL-like molecule-1 (NELL-1) on bone formation in DO. Unilateral tibiae in 48 rabbits were lengthened for 7 days at a rate of 2 mm/day after 3-day lag. At the end of distraction, the animals were randomly divided into four groups (n = 12) and received phosphate-buffered saline, 50 μg rhNell-1 or 50 μg rhBMP-2, or both 25 μg rhBMP-2 and 25 μg rhNell-1 at the lengthened segment, respectively. After 4-week consolidation bony healing was assessed using histology, radiography, dual energy X-ray absorptiometry, micro-CT, and three-point bend testing. Treatment with rhNell-1 and/or rhBMP-2 resulted in better bone formation and higher BMD and BMC than the saline group, whilst excellent bone formation and the highest BMD and BMC was observed in the combined treatment group. Both rhNell-1 and rhBMP-2 groups presented more mature characteristics in the micro-architecture than the saline group, whereas the combined treatment group presented the highest BV/TV, Tb.Th and Tb.N as well as the lowest Tb.Sp. The peak load of the lengthened tibia increased by 71% in the combined treatment group, 54% in the rhBMP-2 group, and 25% in the rhNell-1 group compared to the control group, respectively. This work suggests that BMP-2 and Nell-1 enhance each other's ability and dual delivery of two agents can significantly improve bony healing in tibial DO.     

International recognition of the Ilizarov bone reconstruction techniques: Current practice and research(dedicated to 100~(th) birthday of G. A. Ilizarov)

The Ilizarov method is one of the current methods used in bone reconstruction. It originated in the middle of the past century and comprises a number of bone reconstruction techniques executed with a ring external fixator developed by Ilizarov GA. Its main merits are viable new bone formation through distraction osteogenesis, high union rates and functional use of the limb throughout the course of treatment. The study of the phenomenon of distraction osteogenesis induced by tension stress with the Ilizarov apparatus was the impetus for advancement in bone reconstruction surgery. Since then, the original method has been used along with a number of its modifications developed due to emergence of new fixation devices and techniques of their application such as hexapod external fixators and motorized intramedullary lengthening nails. They gave rise to a relatively new orthopedic subspecialty termed "limb lengthening and reconstruction surgery". Based on a comprehensive literature search, we summarized the recent clinical practice and research in bone reconstruction by the Ilizarov method with a special focus on its modification and recognition by the world orthopedic community. The international influence of the Ilizarov method was reviewed in regard to the origin country of the authors and journal's rating. The Ilizarov method and other techniques based on distraction osteogenesis have been used in many countries and on all populated continents. It proves its international significance and confirms the greatest contribution of Ilizarov GA to bone reconstruction surgery.     

Effects of rapid distraction rate on new bone formation during mandibular distraction osteogenesis in goats

Objective

Distraction osteogenesis typically requires a long treatment period, which can lead to bone and soft-tissue infection and considerable patient discomfort. Use of a rapid distraction rate in craniofacial distraction osteogenesis to shorten the distraction period is possible owing to the unique characteristics of craniofacial bones, including an abundant blood supply and rapid bone healing compared with long bones. The effects of using a rapid distraction rate in the treatment of craniofacial deformities are currently unclear, however. The objective of this study was to investigate the effects of a rapid distraction rate on new bone formation during mandibular distraction osteogenesis in goats.

Methods

Sixteen goats were randomly divided into four groups consisting of four goats each. In Groups A, B, and C, the right mandible of each goat was distracted at a rate of 0.8 mm/d, 1.6 mm/d, and 2.0 mm/d, respectively; Group D was the control group and did not undergo distraction. Six weeks after the conclusion of distraction, bone densitometry and three-point bending testing were performed in all groups.

Results

The mean bone density value of goats in Group A was significantly higher than those of all the other groups (p < 0.05), and the mean bone density value of goats in Group C was significantly lower than those of all the other groups (p < 0.05). The mean curve slope, peak stress, bending modulus, and energy to failure values of Groups A, B, and C were all significantly lower than those of the control group (p < 0.05). As the distraction rate increased, the curve slope and peak stress values gradually declined (p < 0.05).

Conclusions

Use of a rapid distraction rate in mandibular distraction osteogenesis may have detrimental effects on the quality of new bone, despite the abundant blood supply of craniofacial bones.     

Bone transport using the Ilizarov method: a review of complications in 100 consecutive cases

We present the results of treatment of 100 patients (72 men, 28 women) by the Ilizarov method of bone transport using circular (55) and monolateral external fixators (45). A total of 26 femurs (18 monolateral, 8 circular) and 74 tibias (49 circular, 25 monolateral) was examined. There were no significant differences between the circular fixator and the monolateral fixator with regard to treatment time, complications in the treated bone segments or compliance with the presence of the fixator. The main complications (pseudoarthrosis at bone contact points after transport, insufficient ossification of lengthened bone, knee stiffness) were resolved with further treatment for all patients with the exception of one case which continued with repeated infections. The circular fixator allows for deformity corrections during bone transport but the monolateral fixator is tolerated better by patients, especially in those with femoral defects.     

A comparison of two types of free bone grafts as transport discs in segmental distraction for reconstruction of calvarial bone defects: an experimental study

Introduction Several investigations over the past few years have shown that the importance of preserving the blood supply of the transport disc during segmental distraction has been overestimated. It was clearly demonstrated that distraction osteogenesis by local bone transportation could be achieved even with free bone grafts. So far, there have been no systematic investigations into how different types of free bone grafts vary in their function and suitability as transport discs in segmental craniofacial distraction. The aim of this study was to develop criteria to aid the clinician in selecting the most suitable free bone graft for distraction purposes.Materials and methods Under general anesthesia, calvarial defects measuring 6×5 cm were created in 12 adult black head sheep in order to reconstruct them by segmental distraction using two different types of bone grafts as transport discs. Group 1 (n=6) received autotopical membranous bone of the calvarium as the transport segment, while group 2 (n=6) received heterotopical enchondral material from the iliac crest. Distraction was started postoperatively after 5 days at 0.6 mm/day and continued for 7 weeks. After a further 6 weeks of consolidation, the animals were killed and specimens examined macroscopically, radiographically and histologically.Results The significantly better quality of bone regenerates of group 1 was clearly influenced by the significantly better stability of the transport discs connection to the distraction device, the calvaria grafts showing better volume stability and better mechanical resistance during transport than the iliac bone. The influence of both types of bone grafts on the macro- and microstructure of the newly formed bone was clearly evident. The mineralization density of group 2 regenerates was significantly lower than that of group 1 specimens.Conclusion High mechanical stability of the bone graft is a very important point to consider when selecting a free graft for use as transport disc in local bone transport, especially if transport is necessary over long distances.     

Effect of chemotherapeutic agents on distraction osteogenesis. An experimental investigation in rabbits

Limb-salvage operations such as vascularised or non-vascularised osseous grafts and allograft and callus distraction methods have replaced amputations because of the increase in the life expectancy of patients with malignant tumours. In this study we aimed to evaluate the effects of chemotherapeutic agents on distraction osteogenesis. For this purpose, 23 rabbits randomly divided into two groups were included in the study. The experimental group and the control group consisted of 12 rabbits and 11 rabbits, respectively. The experimental group were administered chemotherapeutic agents with the protocol identified in the osteogenic sarcoma regimen. All the subjects were corticotomised in the metaphyseal-diaphyseal region, and both groups underwent distraction with a circular ring fixator. X-ray films, bone scintigraphy and histopathological examination were performed three times during the study. No difference between the two groups was observed in radiological, scintigraphical and histopathological studies carried out before the distraction period and following the end of the distraction period. In this study, it was shown that the use of antineoplastic drugs has no significant negative effect on distraction osteogenesis applied for reconstruction in rabbits. We think that it can be an alternative treatment method in humans as well. Received: 20 February 2000     

Ilizarov bone transport after massive tibial trauma: Case report

IntroductionThis is a case report of extreme lengthening of the tibia of about 14.5 cm using bone transport technique following road traffic accident trauma to the lower limbs. The management of the subsequent massive skeletal defects was challenging to orthopedic surgeons. Based on reported cases, the highest tibial lengthening was 22 cm using bifocal transport, while the highest unifocal tibial lengthening reached 14.5 cm.Case presentationA 20-year-old male driver was brought to the emergency department after a road traffic accident. The patient had a right Gustilo IIIA segmental open tibia fracture with bone loss and other severe injuries. The tibial defect was 14.5 cm and the patient was then admitted for Ilizarov application six months after the accident. Although this case was particularly complicated, full limb length was restored.DiscussionThe management of this case was directed to correct the deformities and achieve equal length of both limbs to restore the normal function. Several new techniques have been developed recently to fill large bone defects. Limb lengthening using bone transport technique by application of Ilizarov ring fixator has been suggested as the leading option in filling massive bone gaps.ConclusionThe use of bone transport technique using Ilizarov external rings has proved to be a minimally invasive and reliable method in managing massive bone defects. Accurate application of the Ilizarov frame and proper transport of the middle segment are important factors alleviating the risk for deviation of the transported segment. However, due to the need for regular follow-ups and monitoring, it demands high compliance from the patient to achieve optimal results.     

Application of distraction osteogenesis in managing bone cysts

Background

Despite the great amount of research concerning bone cysts, there is still no commonly accepted method of treatment. The aim of this study was to evaluate the effectiveness managing bone cyst with hybrid external fixator by distraction osteogenesis.

Materials and methods

Between 1982 and 2009, 25 patients with unicameral (20 patients) and aneurismal (five patients) bone cysts were treated using this method. Eighteen patients had a history of pathological fracture at the same location. Cysts were located in the humerus, femur, tibia, and radius. Median follow-up was 48 (range 31–91) months. Results were evaluated on plain radiographs according to the classification system of Capanna et al. Functional assessment was done using the modified system recommended by Enneking et al.

Results

In our study group of 25 bone cysts, 15 were classified as completely healed and nine as healed with residual radiolucency. Recurrence was observed in one patient. Absence of response to treatment was not observed. All patients had excellent functional outcomes, except one with recurrence who was rated poor.

Conclusions

As bone cysts are found in long bones in 90–95 % of patients, and taking into account our achieved positive results in almost all patients, we recommend this method of distraction osteogenesis as a treatment option. It is an effective, economical method of treatment, which eliminates deformity and restores bone length, especially in patients with pathologic fractures.     

Preliminary experience with motorized distraction for tibial lengthening

Limb lengthening by callus distraction is commonly performed with the use of external fixation. Lengthening is routinely performed by the patient through small increments throughout the course of a day. Ilizarov has shown that both the rate and frequency of distraction are important factors in the quality of osteogenesis. We report the effect of motorized high frequency distraction for tibial lengthening in comparison with manual low-frequency distraction at the same rate. Manual distraction (0.25 mm four times a day) in a group containing 43 tibiae was compared with motorized distraction (1/1,440 mm 1,400 times a day) in a group containing 27 tibiae. There was no significant difference in time to union or in the incidence of complications.     

胫骨骨运输术中对接端新鲜化技术的临床观察

目的:研究胫骨骨运输术中对接端应用骨面新鲜化处理技术的效果。方法:对2014年1月至2019年12月胫骨骨运输术中对接端骨面新鲜化处理手术的20例患者进行分析。其中男15例,女5例;年龄19~62(42.3±11.5)岁;感染性7例,非感染性13例。对接端达到接触后即刻通过使骨面新鲜化处理的手术技术,清除卡入断端的皮肤和软组织,切除硬化封闭的骨端,改善对位,增加接触面积,术中即刻对对接端进行加压,并就近取骨植骨。术后继续逐渐加压。结果:缺损长度5~15(9.2±2.9) cm,从截骨到对接端接触需要26~243(109.1±51.1) d。所有患者对接端达到骨性愈合。达到影像学愈合标准需要3~7(3.7±1.1)个月,20例中15例需要腓骨截骨,其中14例腓骨的截骨端达到骨性愈合。胫骨牵开端的骨痂达到影像学坚实化的时间需要5~28(15.0±6.5)个月,骨愈合指数(bone healing index,BHI)为每厘米需0.8~2.8(1.6±0.5)个月。20例中1例胫骨切口出现感染。拆除外固定架后随访时间为12~73(37.6±20.3)个月,所有患者对接端未发生骨折。结论:胫骨骨运输术中,当对接端接触后尽早进行骨面新鲜化处理能缩短对接端的愈合时间,避免对接端再骨折,术中收集的松质骨和钻孔产生的骨屑能消除缺损和间隙,避免在其他部位取自体骨植骨。     

骨基质明胶影响狗下颌骨牵张成骨的实验研究

目的探讨在牵张区截骨部位加入骨基质明胶（Bone matrix gelatin，BMG），以诱导骨的再生，促进牵张区骨痂愈合，并缩短间歇期及固定期，提高成骨质量，减少并发症。方法选用6只雄性成年杂种狗，随机选取一侧作为实验组（牵张区截骨部位加入BMG），另一侧作为对照组。分别在下颌骨体部安放牵张器，共牵张7d，通过不同时间点的X线观察、组织学观察和灰度分析来评价骨牵张的程度。结果计算机辅助灰度间接计量统计学分析结果：第1周时，对照组和实验组的骨密度间接计量值，两者比较差异无统计学意义。第3周、5周、8周时，对照组和实验组的骨密度间接计量值，两者比较，差异有统计意义。结论在牵张区截骨部位加入BMG，能够诱导骨的再生，可促进牵张区骨痂愈合，缩短牵张成骨整个过程．提高成骨质量，减少并发症。