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1.
Int J Mol Sci ; 21(10)2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32455543

RESUMO

The interference screw fixation method is used to secure a graft in the tibial tunnel during anterior cruciate ligament reconstruction surgery. However, several complications have been reported, such as biodegradable screw breakage, inflammatory or foreign body reaction, tunnel enlargement, and delayed graft healing. Using additive manufacturing (AM) technology, we developed a titanium alloy (Ti6Al4V) interference screw with chemically calcium phosphate surface modification technology to improve bone integration in the tibial tunnel. After chemical and heat treatment, the titanium screw formed a dense apatite layer on the metal surface in simulated body fluid. Twenty-seven New Zealand white rabbits were randomly divided into control and additive manufactured (AMD) screw groups. The long digital extensor tendon was detached and translated into a tibial plateau tunnel (diameter: 2.0 mm) and transfixed with an interference screw while the paw was in dorsiflexion. Biomechanical analyses, histological analyses, and an imaging study were performed at 1, 3, and 6 months. The biomechanical test showed that the ultimate pull-out load failure was significantly higher in the AMD screw group in all tested periods. Micro-computed tomography analyses revealed early woven bone formation in the AMD screw group at 1 and 3 months. In conclusion, AMD screws with bioactive surface modification improved bone ingrowth and enhanced biomechanical performance in a rabbit model.


Assuntos
Parafusos Ósseos/normas , Osseointegração , Impressão Tridimensional , Tendões/cirurgia , Tíbia/cirurgia , Ligas/química , Animais , Parafusos Ósseos/efeitos adversos , Interface Osso-Implante/cirurgia , Fosfatos de Cálcio/química , Porosidade , Coelhos
2.
Int J Pharm ; 582: 119303, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32268183

RESUMO

Osteogenic differentiation is great significance for improving the bone regeneration. Present study evaluates the osteogenic ability of lanthanum (La3+) and silicate (SiO44-) substituted hydroxyapatite (MHAP) - polymeric composite coated surface treated titanium (Ti) implant. The bio-ceramic MHAP was synthesized by hydrothermal process with assistance of calcium alginate template. For enhance the hydrophilicity, the polymer poly (vinyl pyrrolidone) (PVP) was included in the composite by ultra-sonication method. The negative zeta potential value -9.97 mV of Ca-alg/ La, Si-HAP was observed after the incorporation of PVP in the matrix. Incorporation of minerals and PVP polymer was confirmed and analyzed by Energy Dispersive X-ray analysis (EDX), Fourier Transform Infra-Red spectroscopy (FT-IR) and Electron Microscopy techniques. A compact coating of the composite with the thickness of 448 nm on Ti surface was achieved by Electrophoretic deposition (EPD) method. The in-vitro MTT assay method and alkaline phosphate ALP activity (94% and 0.94 a.u respectively for the optimized composite) were utilized to determine the cell viability and differentiation on human Bone Marrow-Derived Stem Cells (hBMSCs). The osteogenic ability of bio-composite coated Ti in hBMSCs and in-vivo rat model has strongly suggests the fabricated Ti plate with bio-composite coatings can act as promising biomaterial for orthopedics.


Assuntos
Alginatos/farmacologia , Prótese Ancorada no Osso , Interface Osso-Implante/cirurgia , Materiais Revestidos Biocompatíveis , Hidroxiapatitas/farmacologia , Osseointegração/efeitos dos fármacos , Tíbia/cirurgia , Titânio/química , Alginatos/química , Fosfatase Alcalina/metabolismo , Animais , Interface Osso-Implante/fisiopatologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Composição de Medicamentos , Humanos , Hidrogéis , Hidroxiapatitas/química , Lantânio/química , Lantânio/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Desenho de Prótese , Ratos Wistar , Recuperação de Função Fisiológica , Silicatos/química , Silicatos/farmacologia , Propriedades de Superfície , Tíbia/fisiopatologia
3.
Biochem Biophys Res Commun ; 517(3): 407-412, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31376931

RESUMO

Periprosthetic asepteic loosening, caused by wear debris, is one of the most severe complications, generally resulting in implant failure. Extensive osteoclast formation and activation are considered as the cause for periprosthetic osteolysis. However, few approaches have been approved to be used for preventing early-stage periprosthetic osteolysis. In this study, we investigated the preventive effects of CEP on titanium particles-induced osteolysis in a murine calvaria model. This inhibitory effect was confirmed to be realized by attenuating osteoclastogenesis in vivo. In addition, CEP markedly reduced wear particles-induced elevation of receptor activator of nuclear factor kappa B ligand (RANKL)/Osteoprotegerin (OPG) ratio in vivo. In conclusion, these data concluded that CEP demonstrated a preventive effect of CEP on titanium particles induced osteolysis, suggesting that CEP might be a novel therapeutic for periprosthesis loosening.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Benzilisoquinolinas/farmacologia , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteólise/prevenção & controle , Osteoprotegerina/genética , Ligante RANK/genética , Titânio/efeitos adversos , Animais , Prótese Ancorada no Osso , Interface Osso-Implante/cirurgia , Catepsina D/genética , Catepsina D/metabolismo , Modelos Animais de Doenças , Regulação da Expressão Gênica , Masculino , Camundongos , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/metabolismo , Osteoclastos/patologia , Osteogênese/genética , Osteólise/induzido quimicamente , Osteólise/genética , Osteólise/patologia , Osteoprotegerina/antagonistas & inibidores , Osteoprotegerina/metabolismo , Falha de Prótese/efeitos dos fármacos , Ligante RANK/antagonistas & inibidores , Ligante RANK/metabolismo , Crânio/efeitos dos fármacos , Crânio/cirurgia , Fosfatase Ácida Resistente a Tartarato/genética , Fosfatase Ácida Resistente a Tartarato/metabolismo
4.
Compend Contin Educ Dent ; 39(suppl 3): 6-10; quiz 11, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30188143

RESUMO

Today, a variety of surgical and prosthetic protocols, implant designs, and prosthetic devices are used for implant dentistry, employing many different dental technologies. With a plethora of options available, choosing an implant system has become highly challenging for practitioners. Having an understanding of the role of different implant design properties may help clinicians make informed decisions. This article provides an overview of factors affecting osseointegration and preservation of bone and discusses the importance of surgical and prosthetic treatments that respect the biologic width and avoid interventions, such as cementation, that may disturb the surrounding soft and hard tissues.


Assuntos
Implantação Dentária/métodos , Implantes Dentários , Tecnologia Odontológica/métodos , Interface Osso-Implante/cirurgia , Implantação Dentária/instrumentação , Planejamento de Prótese Dentária , Gengiva/cirurgia , Humanos , Cirurgia Bucal/métodos
6.
J Am Acad Orthop Surg ; 26(14): 501-505, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29901481

RESUMO

Allograft reconstruction of large segmental intercalary bone defects after tumor resection is a well-accepted surgical technique. Although results generally have been satisfactory, nonunion at the allograft-host bone junction site remains a notable concern. Various reports have described attempts to enhance junctional healing with a variety of complex osteotomies, often complicating an already complex procedure. The use of an innovative reverse reaming technique can decrease the level of intraoperative difficulty mating the allograft-host junction and theoretically may improve junctional healing by enhancing stability and increasing the contact surface area.


Assuntos
Aloenxertos/cirurgia , Neoplasias Ósseas/cirurgia , Transplante Ósseo/métodos , Interface Osso-Implante/cirurgia , Fraturas Ósseas/cirurgia , Adolescente , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteossarcoma/cirurgia , Ossos Pélvicos/cirurgia , Sarcoma de Ewing/cirurgia
7.
Int J Surg ; 54(Pt A): 18-23, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29679723

RESUMO

PURPOSE: This study was designed to compare the surgical outcomes of a hook plate with double-tunnel coracoclavicular (CC) ligament reconstruction by conjoined tendon transfer versus single hook plate surgery for the repair of acute type of Rockwood type III and V acromioclavicular (AC) joint dislocations. METHODS: The study cohort included 62 patients with acute (within 6 weeks after trauma) Rockwood type III and V AC joint dislocations who underwent surgery from February 2012 to September 2015. The patients were randomly allocated to the ligament reconstruction group (LR group, n = 31) or the single hook plate group (HP group, n = 31). In both groups, reduction of the AC joint by hook plate and repair of the ruptured AC ligament with absorbable Vicryl sutures were performed homoplastically. The lateral half of the short tendon of the biceps brachii muscle and the lateral half of the flexor tendon were used to reconstruct the trapezoid and conoid ligaments, respectively. Differences in surgical duration, intraoperative blood loss, incision length, and total cost were compared between the two groups. Furthermore, the preoperative and postoperative visual analogue score (VAS), postoperative American Shoulder and Elbow Surgeons (ASES) score, Constant-Murley score (CMS), Karlsson score, complication rates, and patient satisfaction at the last follow-up were compared to evaluate the curative effects of the surgical treatments. Magnetic resonance imaging (MRI) after hook plate removal was used to evaluate the reconstructed ligaments and tendon-bone interface. RESULTS: In total, 25 patients in the LR group and 26 in the HP group completed the follow-up. There were no statistically significant differences in age, sex, Rockwood type, placing time, total cost, and follow-up duration between the LR and HP groups (p > 0.05). However, as compared with the HP group, the surgical duration and incision length were longer in the LR group (92.08 ±â€¯19.25 vs. 56.54 ±â€¯21.29 min and 13.64 ±â€¯0.90 vs. 6.65 ±â€¯1.01 cm, respectively, p < 0.05). In addition, there was no significant difference in preoperative VAS scores, but the postoperative VAS score was lower in LR group than in the HP group (2.52 ±â€¯1.19 vs. 4.12 ±â€¯1.45, respectively, p < 0.05). Moreover, patients in LR group had a remarkable higher CMS and ASES score (89.56 ±â€¯2.80 vs. 79.31 ±â€¯4.97 and 92.60 ±â€¯2.79 vs. 82.35 ±â€¯3.44, respectively, p < 0.05). The overall excellent or good result rate, as evaluated by the Karlsson score, was 92.00% (23/25) and 50.00% (13/26), respectively (p < 0.05). MRI findings revealed good condition of the reconstructed ligaments and tendon-bone interface. The incidence of complications was lower and the satisfaction rate was higher in the LR group than in the HP group (1/25 vs. 16/26 and 23/25 vs. 14/26, respectively, p < 0.05). CONCLUSIONS: The overall surgical effect of the use of a hook plate combined with double-tunnel CC ligament reconstruction is superior to single hook plate surgery for the repair of acute Rockwood type III and V AC joint dislocations.


Assuntos
Articulação Acromioclavicular/cirurgia , Placas Ósseas , Luxações Articulares/cirurgia , Ligamentos Articulares/cirurgia , Procedimentos Cirúrgicos Reconstrutivos/métodos , Articulação Acromioclavicular/lesões , Adulto , Interface Osso-Implante/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Prospectivos , Tendões/cirurgia , Resultado do Tratamento
8.
J Am Acad Orthop Surg ; 26(8): e167-e172, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29528870

RESUMO

Periprosthetic fractures around total knee arthroplasty have become an increasingly common and challenging orthopaedic problem. Appropriate management of these fractures depends on careful scrutiny of radiographs and a thorough clinical history to exclude the diagnosis of a periprosthetic infection. In a periprosthetic tibial fracture with a stable, well-aligned tibial component and well-aligned mechanical tibial axis, the fracture can be successfully managed with closed reduction and cast immobilization; meticulous follow-up is essential to ensure that the alignment is maintained. Major fracture displacement, tibial component instability, and tibial component malalignment are all indications for surgical intervention. The ideal surgical intervention depends on the fracture characteristics and the stability and alignment of the tibial component.


Assuntos
Artroplastia do Joelho/efeitos adversos , Interface Osso-Implante/lesões , Fraturas Periprotéticas/cirurgia , Reoperação/métodos , Fraturas da Tíbia/cirurgia , Adulto , Idoso , Interface Osso-Implante/cirurgia , Moldes Cirúrgicos , Redução Fechada/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas Periprotéticas/etiologia , Falha de Prótese , Tíbia/cirurgia , Fraturas da Tíbia/etiologia
9.
Clin Oral Implants Res ; 28(11): 1459-1465, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28370489

RESUMO

OBJECTIVES: To evaluate the volumetric changes and peri-implant health at implant sites with and without previous soft tissue grafting over a 5-year observation period. MATERIAL AND METHODS: In 18 partially edentulous patients, dental implants were placed in the esthetic zone (15-25) with simultaneous guided bone regeneration, followed by submerged healing. During the healing phase, eight patients (test) received a subepithelial connective tissue graft, whereas 10 patients (control) did not receive any soft tissue augmentation. Subsequently, abutment connection was performed and final reconstructions were inserted. Impressions were taken 1 week after crown insertion and at 5 years. Obtained casts were scanned and superimposed for volumetric and linear measurements. The mean distance (MD) in the mid-buccal area between the two surfaces and the differences in buccal marginal mucosal level (bMMLchange ) and in ridge width (RWchange ) were evaluated. Peri-implant health was assessed using probing pocket depth (PPD) values, plaque index (PlI) and bleeding on probing (BOP). RESULTS: At a median follow-up time of 60.5 months a median MD of -0.38 mm (Min: -0.94; Max: -0.03) (test) and of -0.51 mm (Min: -0.76; Max: 0.05) (control) was calculated. The level of the margo mucosae (bMMLchange ) demonstrated a median loss of -0.42 mm (Min: -1.1; Max: -0.01) (test) and of -0.33 mm (Min: -1.02; Max: 0.00) (control). The median RWchange ranged between -0.44 mm and -0.73 mm (test) and between -0.49 mm and -0.54 mm (control). Mean PPD values slightly increased, whereas PlI and BOP remained stable over time in both groups. None of the comparisons between the groups revealed statistically significant differences (P > 0.35). A small sample size must be considered, however. CONCLUSIONS: Limited by a retrospective case-control study design, implant sites with and without soft tissue grafting on the buccal side revealed only minimal volumetric and linear changes and stability of peri-implant parameters over 5 years.


Assuntos
Interface Osso-Implante/patologia , Gengiva/transplante , Periodonto/patologia , Adulto , Idoso , Interface Osso-Implante/cirurgia , Estudos de Casos e Controles , Implantação Dentária Endo-Óssea/efeitos adversos , Estética Dentária , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Periodonto/cirurgia , Estudos Retrospectivos
10.
Clin Orthop Relat Res ; 475(9): 2283-2294, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28425054

RESUMO

BACKGROUND: In patients with painful ankle arthrodesis, the surgical treatment is challenging, and may include takedown of ankle arthrodesis and conversion to a total ankle replacement (TAR). This procedure is technically demanding given the altered anatomy after arthrodesis. Few studies have evaluated TAR in the setting of prior arthrodesis. QUESTIONS/PURPOSES: (1) What intraoperative and perioperative complications were observed in patients who underwent conversion of an ankle arthrodesis to a TAR? (2) Was durable fixation achieved at short term, and what was the alignment of the components? (3) What subsequent surgical procedures were performed, including revisions? (4) What improvements were observed in pain, tibiotalar range of motion (ROM), and quality of life? METHODS: Between January 2007 and December 2014, 18 patients with a painful ankle arthrodesis underwent conversion to TAR at our tertiary referral center. During this period, the indications for conversion of ankle arthrodesis to TAR were tibiotalar nonunion or malunion after attempted arthrodesis in patients who declined revision ankle arthrodesis. The goal of revision surgery was to help patients regain hindfoot mobility and to decrease pain. During the study period, all patients who met indications were treated with a conversion procedure. Of the 18 patients included, 14 were men and four were women. The mean age of the patients was 51 ± 7 years. The mean followup was 54 ± 27 months, with no loss to follow up observed. The initial ankle arthrodesis was performed 6 ± 3.5 years before conversion to TAR. In all patients, the conversion to TAR was performed using a nonconstrained cementless three-component prosthesis. Intraoperative and postoperative complications, revision procedures, and prosthesis component loosening were evaluated. Weightbearing radiographs were used to determine the angular alignment of the tibial and talar components using α/ß/γ angles and to analyze the bone-implant interface. Osseointegration was defined as visible trabecular structures at the bone-implant interface without radiolucent lines. The criteria for radiographic loosening was defined as subsidence or migration of prosthesis components and/or a cystic lesion with a diameter at least 2 mm. Clinical assessment included pain evaluation, measurement of ankle ROM, and quality of life. RESULTS: Two of the 18 patients sustained an intraoperative medial malleolar fracture. In three patients, delayed wound healing was observed. At latest followup, four patients had incomplete osseointegration (posterior quarter of the bone-prosthesis interface on the tibial side). None of the 18 patients had prosthesis loosening. In all patients, both components were neutrally aligned. Two patients had painful arthrofibrosis with reduced ROM, which we treated with an open arthrolysis and exchange of mobile-bearing inlay; one other patient is considering a revision for substantial tibial component medial tilt with collapse of the medial arch. At the latest followup, the mean dorsiflexion and plantar flexion were 8.5° ± 3° and 15° ± 5°, respectively. The mean visual analog scale (VAS) score decreased from 9 ± 0.8 to 1.7 ± 1.6 (p < 0.001). The Short Form Health Survey questionnaire (SF-36) physical and mental outcome scores improved from 34 ± 5 to 74 ± 11 (p < 0.001) and from 49 ± 4 to 75.5 ± 7 (p < 0.001). CONCLUSIONS: Conversion of an ankle arthrodesis to a TAR is a technically challenging procedure. In this small series, it was associated with frequent complications including arthrofibrosis, and functional outcomes including postoperative ROM were lower than reported for primary TAR. However, pain and function did improve. Further studies are necessary to address long-term clinical and radiographic outcomes in this patient cohort. LEVEL OF EVIDENCE: Level IV, therapeutic study.


Assuntos
Artrodese/métodos , Artroplastia de Substituição do Tornozelo/métodos , Prótese Articular , Desenho de Prótese , Reoperação/métodos , Adulto , Idoso , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Artralgia/etiologia , Artrodese/efeitos adversos , Artroplastia de Substituição do Tornozelo/efeitos adversos , Interface Osso-Implante/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Complicações Pós-Operatórias/etiologia , Falha de Prótese , Radiografia , Amplitude de Movimento Articular , Reoperação/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento , Suporte de Carga
11.
Clin Orthop Relat Res ; 475(6): 1702-1711, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28194713

RESUMO

BACKGROUND: Endoprostheses using principles of compressive osseointegration have shown good survivorship in several studies involving the lower extremity; however, no series to our knowledge have documented the use of this technology in the management of massive bone loss in the upper limb. QUESTIONS/PURPOSES: (1) What proportion of upper extremity implants using compressive osseointegration fixation principles achieved durable short-term fixation, and what were the modes of failure? (2) What surgical complications resulted from reconstruction using this technique? METHODS: A multiinstitutional retrospective review identified nine patients (five women; four men) who underwent 13 endoprosthetic replacements between 2003 and 2014 using compressive osseointegration (Compliant® Pre-stress Device [CPS]; Biomet Inc, Warsaw, IN, USA) in the upper extremity, including two proximal humeri, two humeral diaphyses, seven distal humeri, and two proximal ulna. During the early part of that period, the indication for use of a compressive prosthesis in our centers was revision of a previous tumor reconstruction (allograft-prosthetic composite or stemmed endoprosthetic reconstruction) (three patients; five implants), or revision arthroplasty with massive bone loss (three patients, four implants); more recently, indications became somewhat more permissive and included posttraumatic bone loss (one patient, one implant), primary bone sarcoma, and resections with very short remaining end segments after diaphyseal resections (two patients, three implants). Minimum followup was 24 months; one patient (one implant) was lost to followup before that time with the implant intact at 14 months and no patients have died. The mean age of the patients was 45 years (range, 21-62 years). Mean followup was 68 months (range, 24-141 months). Implant revision for any cause and for failure of the CPS mechanism was recorded. Modes of failure were categorized as soft tissue, aseptic loosening, structural, infection, and tumor progression; CPS modes of failure were defined as lack of fixation, with or without bone or implant fracture. RESULTS: Of the 12 implants accounted for beyond 2 years, six had undergone revision of any kind. Only two revisions in two patients were attributable to lack of CPS fixation at the bone-implant interface; one of the patients also had periprosthetic and implant fracture develop through the traction bar. Other modes of failure were aseptic loosening of the standard ulnar component (two patients, two implants), bushing wear (one patient; one implant) and infection resulting in two-stage exchange and free soft tissue transfer with retention of the CPS spindle (one patient, one implant). Complications for all nine patients included one transient radial nerve palsy, one ulnar nerve sensory neurapraxia, one superficial infection, and two glenohumeral subluxations, one underwent revision surgery with implantation of a constrained liner. CONCLUSIONS: A compressive osseointegration endoprosthesis is an option for very difficult revisions or sarcoma resection in the upper extremity in which the remaining segment of host bone is too short for a conventional prosthesis. However, surgeons must inform patients that these are salvage operations, and revision surgery is common. Long-term followup of more patients is necessary to further document the survivorship of these implants in the upper extremity. LEVEL OF EVIDENCE: Level IV, therapeutic study.


Assuntos
Artroplastia/efeitos adversos , Neoplasias Ósseas/cirurgia , Osseointegração , Osteossarcoma/cirurgia , Implantação de Prótese/métodos , Reoperação/métodos , Adulto , Artroplastia/métodos , Interface Osso-Implante/cirurgia , Feminino , Humanos , Úmero/cirurgia , Masculino , Pessoa de Meia-Idade , Pressão , Desenho de Prótese , Estudos Retrospectivos , Extremidade Superior/cirurgia , Adulto Jovem
12.
Biomed Res Int ; 2016: 3926941, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27403424

RESUMO

The objective of this investigation is to analyze the influence of trabecular microstructure modeling on the biomechanical distribution of the implant-bone interface. Two three-dimensional finite element mandible models, one with trabecular microstructure (a refined model) and one with macrostructure (a simplified model), were built. The values of equivalent stress at the implant-bone interface in the refined model increased compared with those of the simplified model and strain on the contrary. The distributions of stress and strain were more uniform in the refined model of trabecular microstructure, in which stress and strain were mainly concentrated in trabecular bone. It was concluded that simulation of trabecular bone microstructure had a significant effect on the distribution of stress and strain at the implant-bone interface. These results suggest that trabecular structures could disperse stress and strain and serve as load buffers.


Assuntos
Interface Osso-Implante/fisiologia , Osso Esponjoso/fisiologia , Implantes Dentários para Um Único Dente , Análise do Estresse Dentário/métodos , Mandíbula/fisiologia , Tomografia Computadorizada por Raios X/métodos , Absorciometria de Fóton/métodos , Animais , Interface Osso-Implante/diagnóstico por imagem , Interface Osso-Implante/cirurgia , Osso Esponjoso/diagnóstico por imagem , Osso Esponjoso/cirurgia , Força Compressiva/fisiologia , Simulação por Computador , Cães , Módulo de Elasticidade/fisiologia , Análise de Elementos Finitos , Masculino , Mandíbula/cirurgia , Modelos Biológicos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Estresse Mecânico , Resistência à Tração/fisiologia
13.
Clin Orthop Relat Res ; 474(5): 1224-33, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26831478

RESUMO

BACKGROUND: Bony fixation of cementless orthopaedic implants is not always achieved, particularly in challenging scenarios such as revision surgery, trauma, and tumor reconstruction. An adjunct therapy for improving porous implant fixation could improve the reliability and durability of these reconstructive procedures. QUESTIONS/PURPOSES: In this study, we asked whether there is a positive and dose-dependent effect of the local release of the bisphosphonate alendronate from (1) alendronate/hydroxyapatite (HA) porous-coated titanium implants compared with bare metal porous controls; and (2) alendronate/HA on porous-coated titanium implants compared with HA-coated porous controls with respect to extent of bone ingrowth, bone apposition, and periimplant bone formation in a canine model? METHODS: Three-dimensional printed porous-coated cylindrical implants coated with three different doses (0.02, 0.06, and 0.18 mg/cm(2)) of alendronate were inserted bilaterally in the intramedullary canal of the proximal femora of 15 adult mongrel dogs (age range, 3-9 years; mean, 5 years) weighing between 36 kg and 60 kg (mean, 43 kg). In each dog, an implant coated with HA and one of three different doses of alendronate was inserted on one side while the contralateral femur had a bare metal porous control implant and an identical control implant with a coating of HA. The dose effect of locally released alendronate on the extent of bone ingrowth, bone apposition, and periimplant bone was assessed by backscattered electron microscopy of three pairs of cross-sections taken from each implant at 12 weeks after surgery. A linear mixed model was used to perform the statistical analyses to account for the correlation in the data resulting from the multiple measures performed on each dog. RESULTS: Compared with paired bare metal controls, periimplant bone increased by 92% (p = 0.007), and 114% (p < 0.001) in the femora with the alendronate implants with a dose of 0.06 mg/cm(2), or 0.18 mg/cm(2), respectively. At a dose of 0.02 mg/cm(2), there was no difference (46% change; p = 0.184, with the numbers available). The comparison of the alendronate-dosed implants with their HA-coated controls showed that the intermediate dose of 0.06 mg/cm(2) alendronate had the greatest effect on net bone formation. Bone apposition was enhanced with the 0.06-mg/cm(2) alendronate femoral implants (82%; p = 0.008), although there was no change in bone ingrowth (37% change; p = 0.902, with the numbers available). When compared with the HA-coated control implants, the greatest effect of the alendronate-dosed implants was the increased amount of periimplant bone at the intermediate dose of 0.06-mg/cm(2) (108%, p = 0.009). There was no effect of the low (0.02-mg/cm(2)) and high (0.18-mg/cm(2)) alendronate-dosed implants (4%, and 6%, respectively; p = 0.321, p = 0.502). Overall, all three alendronate-dosed implants revealed little to no effect on bone ingrowth compared with the HA-coated control implants. CONCLUSIONS: The local release of alendronate from a three-dimensional printed porous-coated implant from the three doses studied showed an overall improvement in bone apposition and periimplant bone at the intermediate dose compared with bare metal or with HA-coated controls, although the effect was more pronounced compared with bare metal. Long-term studies to show the effects of localized alendronate delivery and mechanical fixation would be the next step for future studies. CLINICAL RELEVANCE: Local release of alendronate from a three-dimensional printed porous-coated implant may improve the reliability of cementless fixation of currently available porous-coated bare metal implants.


Assuntos
Alendronato/administração & dosagem , Conservadores da Densidade Óssea/administração & dosagem , Materiais Revestidos Biocompatíveis , Fêmur/efeitos dos fármacos , Fêmur/cirurgia , Hidroxiapatitas/química , Osseointegração/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Implantação de Prótese/instrumentação , Titânio/química , Animais , Interface Osso-Implante/diagnóstico por imagem , Interface Osso-Implante/cirurgia , Cães , Relação Dose-Resposta a Droga , Feminino , Fêmur/diagnóstico por imagem , Masculino , Modelos Animais , Porosidade , Desenho de Prótese , Radiografia , Propriedades de Superfície
14.
Biomed Res Int ; 2016: 4385279, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28116296

RESUMO

The purpose of this study was to compare and evaluate, through histomorphometric and radiological analysis, the effects of UV photofunctionalization on an implant placed over a critical defect area with and without a bone graft. Four female beagle dogs were first divided into control and bone graft groups. Each group was then subdivided into UV-treated and UV-untreated groups. The mandibular premolars in each dog were extracted. 12 weeks after extraction, implants were placed according to the condition of each group. Four and 12 weeks after implantation on left and right mandible, the dogs were sacrificed. The specimens were prepared for histomorphometric and micro-computed tomographic analysis. In both 4-week and 12-week groups, UV-treated implant surfaces showed better osseointegration than SA implant surfaces. Also, with implant surfaces placed over the critical defect with bone graft, UV photofunctionalization increased bone-to-implant contact (BIC) and new bone formation at the initial stage (4 weeks). Based on the results of this study, it can be suggested that UV photofunctionalization on the surface of implants placed over large critical defects with bone graft aids initial osseointegration and osteogenesis.


Assuntos
Transplante Ósseo/métodos , Interface Osso-Implante/efeitos da radiação , Implantes Dentários , Mandíbula/patologia , Mandíbula/cirurgia , Terapia Ultravioleta/métodos , Animais , Interface Osso-Implante/patologia , Interface Osso-Implante/cirurgia , Terapia Combinada/métodos , Cães , Feminino , Mandíbula/efeitos da radiação , Projetos Piloto , Resultado do Tratamento
15.
Acta Bioeng Biomech ; 18(4): 21-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28133377

RESUMO

PURPOSE: The study was aimed at biomechanical evaluation of a novel Limb Prosthesis Osseointegrated Fixation System (LPOFS) designed to combine the advantages of interference-fit and threaded solutions. METHODS: Three cases, the LPOFS (designed), the OPRA (threaded) and the ITAP (interference-fit) implants were studied. Von-Mises stresses in bone patterns and maximal values generated while axial loading on an implant placed in bone and the force reaction values in contact elements while extracting an implant were analysed. Primary and fully osteointegrated connections were considered. RESULTS: The results obtained for primary connection indicate more effective anchoring of the OPRA, however the LPOFS provides more appropriate stress distribution (lower stress-shielding, no overloading) in bone. In the case of fully osteointegrated connection the LPOFSs kept the most favourable stress distribution in cortical bone which is the most important long-term feature of the implant usage and bone remodelling. Moreover, in fully bound connection its anchoring elements resist extracting attempts more than the ITAP and the OPRA. CONCLUSIONS: The results obtained allow us to conclude that in the case of features under study the LPOFS is a more functional solution to direct skeletal attachment of limb prosthesis than the referential implants during short and long-term use.


Assuntos
Cotos de Amputação/fisiopatologia , Membros Artificiais , Interface Osso-Implante/fisiopatologia , Modelos Biológicos , Ajuste de Prótese/instrumentação , Implantação de Prótese/instrumentação , Cotos de Amputação/cirurgia , Parafusos Ósseos , Interface Osso-Implante/cirurgia , Simulação por Computador , Desenho Assistido por Computador , Análise de Falha de Equipamento , Análise de Elementos Finitos , Humanos , Ajuste de Prótese/métodos , Implantação de Prótese/métodos , Resultado do Tratamento
16.
Clin Implant Dent Relat Res ; 17 Suppl 2: e613-20, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25876078

RESUMO

BACKGROUND: Quantitative intraoperative evaluation of bone quality at implant placement site and postinsertion implant primary stability assessment are two key parameters to perform implant-supported rehabilitation properly. A novel micromotor has been recently introduced allowing to measure bone density at implant placement site and to record implant insertion-related parameters, such as the instantaneous, average and peak insertion torque values, and the insertion torque/depth integral. PURPOSE: The aim of this study was to investigate in vivo if any correlation existed between initial bone-to-implant contact (BIC) and bone density and integral values recorded with the instrument. MATERIALS AND METHODS: Twenty-five patients seeking for implant-supported rehabilitation of edentulous areas were consecutively treated. Before implant placement, bone density at the insertion site was measured. For each patient, an undersized 3.3 × 8-mm implant was placed, recording the insertion torque/depth integral values. After 15 minutes, the undersized implant was retrieved with a 0.5 mm-thick layer of bone surrounding it. Standard implants were consequently placed. Retrieved implants were analyzed for initial BIC quantification after fixation, dehydration, acrylic resin embedment, sections cutting and grinding, and toluidine-blue and acid fuchsine staining. Correlation between initial BIC values, bone density at the insertion site, and the torque/depth integral values was investigated by linear regression analysis. RESULTS: A significant linear correlation was found to exist between initial BIC and (a) bone density at the insertion site (R = 0.96, explained variance R(2) = 0.92) and (b) torque/depth integral at placement (R = 0.81, explained variance R(2) = 0.66). CONCLUSIONS: The system provided quantitative, reliable data correlating significantly with immediate postinsertion initial BIC, and could therefore represent a valuable tool both for clinical research and for the oral implantologist in his/her daily clinical practice.


Assuntos
Processo Alveolar/cirurgia , Interface Osso-Implante/cirurgia , Implantes Dentários , Análise do Estresse Dentário/métodos , Adulto , Idoso , Processo Alveolar/patologia , Densidade Óssea , Implantação Dentária Endo-Óssea , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Torque
17.
J Med Imaging Radiat Oncol ; 59(5): 605-7, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25677047

RESUMO

Gout is known to occur in a variety of organs but most commonly presents as an inflammatory arthropathy. A few reported cases have documented its occurrence in prosthetic neo-joints or juxta-articular to this. We present the first reported case at a bone prosthesis interface remote from any joint and mimicking sarcoma recurrence because of its unusual location.


Assuntos
Neoplasias Ósseas/cirurgia , Interface Osso-Implante/diagnóstico por imagem , Gota/diagnóstico por imagem , Gota/etiologia , Prótese do Joelho/efeitos adversos , Osteossarcoma/cirurgia , Neoplasias Ósseas/complicações , Neoplasias Ósseas/diagnóstico por imagem , Interface Osso-Implante/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Osteossarcoma/complicações , Osteossarcoma/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
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