Implant fixation by bone ingrowth

The term osseointegration referred originally to an intimate contact of bone tissue with the surface of a titanium implant; the term bone ingrowth refers to bone formation within an irregular (beads, wire mesh, casting voids, cut grooves) surface of an implant. The section dealing with the historical background describes the development of macroporous, microporous, and textured surfaces with an emphasis on the evolution of porous and textured metal surfaces. The principal requirements for osseointegration and bone ingrowth are systematically reviewed as follows: i) the physiology of osseointegration and bone ingrowth, including biomaterial biocompatibility with respect to cellular and matrix response at the interface; ii) the implant surface geometry characteristics; iii) implant micromotion and fixation modes; and iv) the implant-bone interface distances. Based on current methods of bone ingrowth assessment, this article comparatively reviews and discusses the results of experimental studies with the objective of determining local and systemic factors that enhance bone ingrowth fixation.     

Magnetic Resonance–Visible Meshes for Laparoscopic Ventral Hernia Repair

Methods:Ten patients were surgically treated with intraperitoneally positioned superparamagnetic flat meshes. A magnetic resonance investigation with a qualified protocol was performed on postoperative day 1 and at 3 months postoperatively to assess mesh appearance and demarcation. The total magnetic resonance–visible mesh surface area of each implant was calculated and compared with the original physical mesh size to evaluate potential reduction of the functional mesh surfaces.Results:We were able to show a precise mesh demarcation, as well as accurate assessment of the surrounding tissue, in all 10 cases. We documented a significant decrease in the magnetic resonance–visualized total mesh surface area after release of the pneumoperitoneum compared with the original mesh size (mean, 190 cm² vs 225 cm²; mean reduction of mesh area, 35 cm²; P < .001). At 3 months postoperatively, a further reduction of the surface area due to significant mesh shrinkage could be observed (mean, 182 cm² vs 190 cm²; mean reduction of mesh area, 8 cm²; P < .001).Conclusion:The new method of combining magnetic resonance imaging and meshes that provide enhanced signal capacity through direct integration of iron particles into the polyvinylidene fluoride base material allows for detailed mesh depiction and quantification of structural changes. In addition to a significant early postoperative decrease in effective mesh surface area, a further considerable reduction in size occurred within 3 months after implantation.     

An in vivo evaluation of bone response to three implant surfaces using a rabbit intramedullary rod model

Our study was designed to evaluate osseointegration among implants with three surface treatments: plasma-sprayed titanium (P), plasma-sprayed titanium with hydroxyapatite (PHA), and chemical-textured titanium with hydroxyapatite (CHA). Average surface roughness (Ra) was 27 microns for the P group, 17 microns for the PHA group, and 26 microns for the CHA group. Bilateral distal intramedullary implants were placed in the femora of thirty rabbits. Histomorphometry of scanning electron microscopy images was used to analyze the amount of bone around the implants at 6 and 12 weeks after implantation. Greater amounts of osseointegration were observed in the hydroxyapatite-coated groups than in the noncoated group. For all implant surfaces, osseointegration was greater at the diaphyseal level compared to the metaphyseal level. No significant differences were seen in osseointegration between the 6 and 12 week time points. Although the average surface roughness of the P and the CHA groups was similar, osseointegration of the CHA implants was significantly greater. The results of this in vivo lapine study suggest that the presence of an hydroxyapatite coating enhances osseointegration despite similarities in average surface roughness.     

The bone-implant interface: a dynamic surface.

This study quantifies and compares bone formation on and around roughened titanium implants with roughened cobalt chromium, polished solid implants, and titanium fibermetal implants. Cylindrical rods were implanted into the medullary canal of the distal femur of rabbits. The bone-implant interface was studied 3, 6, and 12 weeks after surgery using histomorphometric methods. Roughened surface implants demonstrated significantly more bone directly apposed to the surfaces when compared to the polished or fiber/metal implants at 6 and 12 weeks after surgery. New bone formation and remodeling of bone occurred directly on roughened surfaces as late as 12 weeks after implantation, but not on the unroughened implants. These results suggest that roughening of the surfaces of both titanium and cobalt chromium implants can enhance osseointegration and may be useful clinically for the fixation of prosthetic components.     

The osseous response to corundum blasted implant surfaces in a canine hip model.

The purpose of this study was to examine the radiographic and histologic response to corundum blasted implant surfaces of varying roughness in a canine total hip arthroplasty model. Three types of tapered femoral implants were made from titanium alloy and were identical in every respect except surface finish. The entire surface of the femoral implant had a 2.9-, 4.2-, or 6.7-micron average surface roughness (Ra) from blasting with 60-, 24-, or 16-grit corundum particles, respectively. Twenty-two stems in 11 dogs were evaluated at 6 months. Twenty-one of the stems showed osseointegration, whereas in one stem a fibrous interface developed. Abundant new periimplant bone formation occurred, particularly within the intramedullary canal where trabeculae spanned implant to endosteal cortex gaps as large as 5 mm. Bone apposition with the 60-, 24-, and 16-grit stems averaged 31.7%, 32%, and 27.9%, respectively; the differences were not statistically significant. However, the pattern of new bone formation was different in that the average length of each region of bone apposition for the 60- and 24-grit surfaces was 50% greater than that for the coarser 16-grit surface. The observations of this study indicate that because of their highly osteoconductive nature, corundum blasted surfaces represent an important and valuable technology for the design of noncemented implants.     

The effect of Er:YAG laser irradiation on the scanning electron microscopic structure and surface roughness of various implant surfaces: an in vitro study

The purpose of this study was to evaluate the surface roughness (R_a) and microscopic change to irradiated dental implant surfaces in vitro and ultimately to determine the proper pulse energy power and application time for the clinical use of Er:YAG lasers. Anodic oxidized surface implants and sand-blasted, large-grit, and acid-etched (SLA) surface implants were used. Each experimental group of implant surfaces included ten implants. Nine implants were used for the laser irradiation test groups and one for the control group. Each test group was equally divided into three subgroups by irradiated pulse energy power. Using an Er:YAG laser, each subgroup of anodic oxidized surface implants was split into 60-, 100-, and 140-mJ/pulse groups, with each subgroup of SLA surface implants irradiated with a 100-, 140-, or 180-mJ/pulse. Three implants in every test subgroup were respectively irradiated for 1, 1.5, and 2 min. The R_a values for each specimen were recorded and every specimen was observed by SEM. Irradiation by Er:YAG laser led to a decrease in implant surface roughness that was not statistically significant. In anodic oxidized surfaces, the oxidized layer peeled off of the surface, and cracks appeared on implant surfaces in the 100- and 140-mJ/pulse subgroups. However, with SLA surfaces, no significant change in surface texture could be found on any implant surface in the 100- and 140-mJ/pulse subgroups. The melting and fusion phenomena of implant surfaces were observed with all application times with 180 mJ/pulse irradiation. The SLA implant surfaces are stable with laser intensities of less than 140 mJ/pulse and an irradiation time of less than 2 min. The anodic oxidized surfaces were not stable with laser intensities of 100 mJ/pulse when an Er:YAG laser was used to detoxify implant surfaces.     

仿生电活性涂层钛植入材料促进骨结合的实验研究

目的评价仿生电活性钛酸钡(BaTiO3,BTO)/聚偏氟乙烯-三氟乙烯P(VDF-TrFE)涂层钛植入材料促进骨结合性能的效果。方法首先将直径为2 mm、长度为5 mm的医用纯钛圆柱进行表面喷砂-酸蚀处理,然后将BaTiO3/P(VDF-TrFE)溶液均匀涂覆在钛柱表面。待烘干后对涂层表面进行电晕极化处理。采用扫描电镜、能谱分析、原子力显微镜、水接触角测量仪分别对材料表面形貌、元素组成、表面粗糙度和亲疏水性进行表征检测,PLLA涂层钛柱作为对照材料。选取实验兔4只,在双侧胫骨位置各制备3个间隔为1 cm的圆形缺损,在左侧胫骨植入PLLA涂层钛柱,右侧胫骨植入仿生电活性涂层钛柱,术后4周和12周分别取材进行硬组织的骨形态检测分析。采用SPSS15.0软件对数据进行统计分析。结果理化性能表征检测显示,BaTiO3/P(VDF-TrFE)涂层和PLLA涂层均匀附着在钛柱表面,涂层厚度约50μm,且表面结构致密。电活性涂层可见钛酸钡纳米颗粒均匀分布在P(VDF-TrFE)基体内。两种涂层表面的粗糙度和水接触角无明显差异。电活性涂层具有稳定的压电性能,且压电常数接近生理量级。动物实验显示,术后4周,仿生电活性涂层材料表面和新骨结合紧密,涂层材料稳定无降解;而PLLA涂层材料表面由于材料有部分降解导致新骨结合较差,电活性涂层的骨结合率明显高于PLLA涂层。术后12周,两组的新骨成熟程度均增加,骨陷窝明显,仿生电活性涂层仍然保持稳定状态;而PLLA涂层进一步发生降解,和新骨结合程度弱于电活性涂层组。结论仿生电活性BaTiO3/P(VDF-TrFE)涂层钛可能作为一种具有促进骨整合功能的种植体涂层材料。     

Peri-implant bone reactions at delayed and immediately loaded implants: an experimental study.

OBJECTIVE: The aim of this study was to compare the peri-implant bone reactions of implants subjected to immediate loading with those subjected to delayed loading. STUDY DESIGN: In 6 mongrel dogs, bilateral edentulated flat alveolar ridges were created in the mandible. After 3 months of healing, 1 implant was placed in each side. On one side of the mandible, the implant was loaded immediately with a force of 20 N that was applied at a 120 degrees angle from the tooth's longitudinal axis at the labial surface of the crown for 1800 cycles per day for 10 weeks. On the opposite side, after a delay of 3 months to allow osseointegration to take place, the implant was loaded with the same force used for the immediately loaded implant. Ten weeks after loading, microscopic computerized tomography at the implantation site was performed. Osseointegration was calculated as the percentage of implant surface in contact with bone. Bone height was measured in the peri-implant bone. RESULTS: The mean osseointegration was greater (65.5%) for the delayed-loading implants than for the immediately loaded implants (60.9%; P < .05). The mean peri-implant bone height was greater (10.6 mm) for the delayed-loading implants than for the immediately loaded implants (9.6 mm; P < .05). CONCLUSION: The results indicate that when implants are immediately loaded, the immediate loading may decrease both osseointegration of dental implants and bone height.     

Early loading of hydrophilic titanium implants inserted in low-mineralized (D3 and D4) bone: one year results of a prospective clinical trial

Introduction

Pure titanium is the material of choice for contemporary dental implants. However, superficial reaction of the moderately rough titanium surface with atmospheric components decreases its hydrophilicity. INICELL® represents a chemical alteration and hydrophilization of a moderately rough i. e. sand-blasted and acid-etched titanium surface. The hydrophilicity leads to a more homogenous adsorption of proteins on the implant surface in-vitro, supporting the activation of a higher number of platelets and the generation of a homogenous, complete fibrin matrix in the early phases of osseointegration. This in turn helps to reduce the healing time and enhances the predictability of osseointegration in compromised bony situations.The objective of this case series trial was therefore to investigate if early loading (after 8 weeks) of hydrophilic INICELL implants is feasible in patients with reduced bone quality.

Methods

In 10 patients, 35 hydrophilic implants were placed in sites revealing bone quality class 3 and 4, and uncovered after 4 weeks. Eight weeks later implants were released for loading if the tactile resistance was ≥35 Ncm. Lower resistances resulted in 12 weeks initial healing period. Insertion torque, ISQ, tactile resistance and vertical bone level were evaluated at implant installation, after 4 weeks (uncovering), 8 or 12 weeks (loading), and 12 weeks and one year after loading.

Results

Mean implant insertion torque was 21 Ncm. 31 (88.6%) showed a tactile resistance of >35 Ncm after eight weeks and were released for prosthetic loading. Eight weeks after insertion, one implant (2.9%) had to be removed following a soft tissue complication. One implant had to be removed after 4 weeks due to a technical complication (fractured Osstell-abutment), it was therefore excluded from the analysis.33 of 34 implants (97%) were loaded to occlusion and were in situ/functional one year after implantation. ISQs increased from 43 at baseline to 63 at eight weeks, and 72 at three months after loading. Then, ISQ remained constant until one year after loading.

Conclusions

Within the limitations of this prospective case series, hydrophilic implants may allow for shortening of the initial healing period even in bone with compromised density.

     

Flapless implant surgery: an experimental study.

OBJECTIVE: The purpose of this study was to examine the effect of flapless implant surgery on crestal bone loss and osseointegration in a canine mandible model. STUDY DESIGN: In 6 mongrel dogs, bilateral, edentulated, flat alveolar ridges were created in the mandible. After 3 months of healing, 2 implants in each side were placed by either flap or flapless procedures. After a healing period of 8 weeks, microcomputerized tomography at the implantation site was performed. Osseointegration was calculated as percentage of implant surface in contact with bone. Additionally, bone height was measured in the peri-implant bone. RESULTS: The mean osseointegration was greater at flapless sites (70.4%) than at sites with flaps (59.5%) (P < .05). The mean peri-implant bone height was greater at flapless sites (10.1 mm) than at sites with flaps (9.0 mm) (P < .05). CONCLUSION: Flapless surgery can achieve results superior to surgery with reflected flaps. The specific improvements of this technique include enhanced osseointegration of dental implants and increased bone height.     

The effect of hierarchical micro/nanosurface titanium implant on osseointegration in ovariectomized sheep

Summary  

Hydrofluoric etching and anodized hierarchical micro/nanotextured surface titanium implant was placed in mandibles of ovariectomized sheep for 12 weeks, and it showed improved osseointegration by resonance frequency analysis (RFA), microcomputed tomography (micro-CT) evaluation, histomorphometry, and biomechanical test.     

Differences in stiffness of the interface between a cementless porous implant and cancellous bone in vivo in dogs due to varying amounts of implant motion

To determine the mechanical properties of the interface between the tissue ingrowth into porous coatings and the implant, porous-coated cylindrical implants were inserted into the distal femur in 20 mature dogs and oscillated in vivo 8 hours per day for 6 weeks at fixed amounts of micromotion (0, 20, 40, and 150 μm). Applied torques and resulting displacements were recorded. The torsional resistance per unit angular displacement (TR/AD), reflecting the stiffness of the bone—porous coating interface, was 0.88 ± 0.25 N-M/deg immediately after implantation in the 20-μm displacement group. It increased with time after surgery, reaching a maximum of 1.25 ± 0.60 N-M/deg at 6 weeks. The TR/AD was lower initially (0.77 ± 0.43 N-M/deg) in the 40-μm group and gradually decreased with time after surgery, reaching a maximum of 0.54 ± 0.13 N-M/deg at 6 weeks. The TR/AD was even lower (0.24 ± 0.10 N-M/deg) in the 150-μm group initially and remained the same (0.16 ± 0.09 N-M/deg) with time after surgery. Histologic evaluation showed bone ingrowth in continuity with the surrounding bone in the 20-μm group consistent with the high stiffness values at sacrifice. In contrast, a mixture of fibrocallus and bone were found at the bone-porous coating interface in the 40-μm group, consistent with the intermediate stiffness values. In contrast, despite the fact that bone was found in the depth of the porous coating in the dogs in the 150-μm group, the low stiffness values were a reflection of fibrous tissue formation at the interface in that group, because of the large motion disrupting bony ingrowth at the bone—porous coating interface. By monitoring the torsional resistance per unit of angular displacement dynamically in vivo, it was possible to evaluate the mechanical properties of the bone—porous coating interface as tissue ingrowth proceeded. Twenty microns of oscillating displacement was compatible with stable bone ingrowth with high interface stiffness, whereas 40 and 150 μm of motion was not.     

Tissue-implant interface at an absorbable fracture fixation plug made of polylactide in cancellous bone of distal rabbit femur

The tissue-implant interface at a self-reinforced poly-l-lactide (SR-PLLA) expansion plug implanted in distal rabbit femoral cancellous bone was studied histologically, histomorphometrically, and microradiographically in 35 rabbits during consolidation of a transverse transcondylar osteotomy fixed with the SR-PLLA expansion plug. The absorbable plug for internal fixation of fractures and osteotomies measured 4.5 mm in diameter and 30 mm in length and had an expandable distal locking blade system. The femoral specimens were harvested in groups of 5–10 rabbits after a follow-up time of 3, 6, 12, and 24 weeks. The intact controlateral femur served as a control. Vigorous osteogenic response to the implant was already observed at 3 weeks postoperatively, and the osteoid surface fraction at 24 weeks was still significantly higher than in the unoperated contralateral femur. Incomplete union of the osteotomy seemed to result in increased fibrous tissue formation at the tissue-implant boundary. No signs of degradation of the SR-PLLA was observed within the entire follow-up period. The number of inflammatory cells at the tissue-implant interface was low. Consequently, the short-term biocompatibility of the implant was deemed acceptable. Clinical application of the expansion plug is being planned.     

In vivo monitoring of implant osseointegration in a rabbit model using acoustic sound analysis

Implant osseointegration can currently only be assessed reliably post mortem. A novel method that relies on the principle of acoustic sound analysis was developed to enable examination of the longitudinal progress of osseointegration. The method is based on a magnetic sphere inside a hollow cylinder of the implant. By excitation using an external magnetic field, collision of the sphere inside the implant produces a sound signal. Custom‐made titanium implants equipped thusly were inserted in each lateral femoral epicondyle of 20 New Zealand White Rabbits. Two groups were investigated: Uncoated, machined surface versus antiadhesive surface; and calcium phosphate‐coated surface versus antiadhesive surface. The sound analysis was performed postoperatively and weekly. After 4 weeks, the animals were euthanized, and the axial pull‐out strengths of the implants were determined. A significant increase in the central frequency was observed for the loose implants (mean pull‐out strength 21.1 ± 16.9 N), up to 6.4 kHz over 4 weeks. In comparison, the central frequency of the osseointegrated implants (105.2 ± 25.3 N) dropped to its initial value. The presented method shows potential for monitoring the osseointegration of different implant surfaces and could considerably reduce the number of animals needed for experiments. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:606–612, 2014.     

3D-printed titanium cages without bone graft outperform PEEK cages with autograft in an animal model

BACKGROUND CONTEXTModernization of 3D printing has allowed for the production of porous titanium interbody cages (3D-pTi) which purportedly optimize implant characteristics and increase osseointegration; however, this remains largely unstudied in vivo.PURPOSETo compare osseointegration of three-dimensional (3D) titanium cages without bone graft and Polyether-ether-ketone (PEEK) interbody cages with autologous iliac crest bone graft (AICBG).STUDY DESIGNAnimal study utilizing an ovine in vivo model of lumbar fusion.METHODSInterbody cages of PEEK or 3D-pTi supplied by Spineart SA (Geneva, Switzerland) were implanted in seven living sheep at L2-L3 and L4-L5, leaving the intervening disc space untreated. Both implant materials were used in each sheep and randomized to the aforementioned disc spaces. Computed tomography (CT) was obtained at 4 weeks and 8 weeks. MicroCT and histological sections were obtained to evaluate osseointegration.RESULTSMicroCT demonstrated osseous in-growth of native cancellous bone in the trabecular architecture of the 3D-pTi interbody cages and no interaction between the PEEK cages with the surrounding native bone. Qualitative histology revealed robust osseointegration in 3D-pTi implants and negligible osseointegration with localized fibrosis in PEEK implants. Evidence of intramembranous and endochondral ossification was apparent with the 3D-pTi cages. Quantitative histometric bone implant contact demonstrated significantly more contact in the 3D-pTi implants versus PEEK (p<.001); region of interest calculations also demonstrated significantly greater osseous and cartilaginous interdigitation at the implant-native bone interface with the 3D-pTi cages (p=.008 and p=.015, respectively).CONCLUSIONS3D-pTi interbody cages without bone graft outperform PEEK interbody cages with AICBG in terms of osseointegration at 4 and 8 weeks postoperatively in an ovine lumbar fusion model.CLINICAL SIGNIFICANCE3D-pTi interbody cages demonstrated early and robust osseointegration without any bone graft or additive osteoinductive agents. This may yield early stability in anterior lumbar arthrodesis and potentially bolster the rate of successful fusion. This could be of particular advantage in patients with spinal neoplasms needing post-ablative arthrodesis, where local autograft use would be ill advised.     

Strength of Tissue Attachment to Composite and ePTFE Grafts After Ventral Hernia Repair

Objectives:

We sought to measure the strength of tissue attachment to mesh after laparoscopic ventral hernia repair in a porcine model.

Methods:

Twelve swine had two 10-cm × 16-cm sheets of ePTFE and polypropylene/ePTFE composite mesh fixated to the abdominal wall laparoscopically. Animals were euthanized at 2, 4, 6, and 12 weeks. The strength of tissue ingrowth was measured using a lap-shear method. Data are reported as mean force in pounds.

Results:

Average surface area of adhesions to percentage of surface area was not statistically significant between the composite and ePTFE materials. For the composite material, there was a 98.7% posterior probability that the force required at 2 weeks was less than that required at 12 weeks. There was no difference in graft-abdominal wall interface strength between week 2 and week 12 for ePTFE material. Both prosthetics achieved the majority of their strength from tissue ingrowth by 2 weeks, but the composite prosthesis continued to gain strength while the strength of the ePTFE plateaued. Composite mesh demonstrated a statistically significant increase in strength between the lap-shear force, whereas no statistically significant difference occurred in the ePTFE graft. For the composite material, there was complete cellular infiltration through the entire thickness of polypropylene (approximately 500 μm) to the ePTFE layer at 2 weeks. At 2 weeks for ePTFE, the cells did not penetrate into the graft on the visceral side. On the abdominal wall side, the grooves filled with tissue, but no cellular penetration into the ePTFE occurred. No histological difference existed in cellularity.

Conclusion:

This study demonstrates that the strength of tissue ingrowth is significantly higher (P<0.05) for the composite grafts relative to the ePTFE grafts at each time point. Approximately 74% of tissue ingrowth and strength occurs by 2 weeks postoperatively for the composite pros-thesis. The ePTFE graft tissue strength peaked and plateaued by 2 weeks. This may have clinical implications for human ventral hernia repair by partly addressing the issue of graft fixation to the abdominal wall during laparoscopic ventral hernia repair.     

Relative contributions of chemistry and topography to the osseointegration of hydroxyapatite coatings

The purpose of the current study was to ascertain the relative contributions of surface chemistry and topography to the osseointegration of hydroxyapatite-coated implants. A canine femoral intramedullary implant model was used to compare the osseous response to commercially pure titanium implants that were either polished, grit-blasted, plasma-sprayed with hydroxyapatite, or plasma-sprayed with hydroxyapatite and masked with a very thin layer of titanium using physical vapor deposition (titanium mask). The titanium mask isolated the chemistry of the underlying hydroxyapatite layer without functionally changing its surface topography and morphologic features. At 12 weeks, the bone-implant specimens were prepared for undecalcified thin section histologic evaluation and serial transverse sections were quantified with backscattered scanning electron microscopy for the percentage of bone apposition to the implant surface. Bone apposition averaged 3% for the polished implants and 23% for the grit-blasted implants. Bone apposition to the hydroxyapatite-coated implants averaged 74% whereas bone apposition to the titanium mask implants averaged 59%. Although there was significantly greater osseointegration with the hydroxyapatite-coated implants, 80% of the maximum bone forming response to the implant surfaces developed with the titanium mask implants. This simple, controlled experiment revealed that topography is the dominant factor governing bone apposition to hydroxyapatite-coated implants.     

Osseointegration in arthroplasty: can simvastatin promote bone response to implants?

Cementless fixation depends on bone ingrowth for long-term success. Simvastatin as a lipid lowering agent has been demonstrated to have osteoanabolic effects. This study was designed to measure the possible effect of simvastatin on implant osseointegration. Bilateral femoral implantation of titanium cylinders was performed in 20 rabbits. Blood lipid levels were measured pre- and postoperatively. Scanning electron microscopy (SEM) was used to measure the percentage of the surface of each implant in contact with bone and mechanical pull-out testing was performed. The blood lipid levels were significantly reduced in the simvastatin group. Histomorphometric examination revealed increased bone ingrowth and mechanical examination showed increased interface strength in the simvastatin group. Mechanical and histological data showed superior stability and osseous adaptation at the bone/implant interface for the simvastatin group. We conclude that simvastatin has potential as a means of enhancing bone ingrowth, which is a key factor in the longevity of cementless implants.     

掌指骨髓腔内骨整合式纯钛种植体的设计及界面生物力学研究

目的:自行开发设计掌指骨髓腔内骨整合式纯钛螺旋状种植体组件,通过动物实验对种植体-骨组织结合界面进行生物力学研究,为临床中种植体式手指赝复体修复指缺损提供依据。方法:根据成人正常掌骨和近节指骨及其髓腔的解剖学测量及特点,借鉴Branemark螺旋形牙种植体,研制开发临床用于掌指骨髓腔内植入的骨整合式纯钛螺旋状种植体。将此种种植体植入家兔胫骨髓腔内,术后分别于2、4、8、12、16周处死动物取材,进行大体观察和抗拉力测试。结果:制备出适合于成人掌指骨髓腔内植入的骨整合式纯钛螺旋型种植体组件及配件,种植体与骨可以形成良好的骨性结合,术后12周种植体-骨界面结合强度达到最大,与术后16周无明显差异。结论:该掌指骨髓腔内骨整合式纯钛螺旋状种植体组件自行开发设计,符合我国成人正常掌骨和近节指骨及其髓腔的解剖学特点,髓腔内植入后12周可与骨组织发生骨整合,达到最大结合强度。