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1.
Diagnostics (Basel) ; 13(9)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37174983

RESUMO

Both musculoskeletal gossypibomas and chronic expanding hematomas have been rarely reported; the reports that do exist are usually case reports. Our objective is to demonstrate problematic imaging diagnostics of an unusual presentation mimicking a malignant lesion. We report the case of a 47-year-old man who underwent bone graft harvesting from the iliac crest for spinal fusion due to scoliosis at 18 years of age, and 29 years later, he developed a growing, painful tumor at the original donor site (a bone defect in the iliac crest). It was challenging to differentiate a hematoma from a malignant tumor based solely on clinical and radiological workup, including an ultrasound-guided needle biopsy focused on viable tissue. The definitive diagnosis of a gossypiboma with a chronic expanding hematoma was based on histopathological assessment after wide surgical resection-a chronic expanding hematoma with multiple foamy macrophages and giant cells engulfing foreign material (original surgical hemostatic sponge).

2.
World Neurosurg ; 175: e693-e703, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37037366

RESUMO

BACKGROUND: Cranioplasty after craniectomy can result in high rates of postoperative complications. Although determinants of postoperative outcomes have been identified, a prediction model for predicting cranioplasty implant survival does not exist. Thus, we sought to develop a prediction model for cranioplasty implant survival after craniectomy. METHODS: We performed a retrospective cohort study of patients who underwent cranioplasty following craniectomy between 2014 and 2020. Missing data were imputed using multiple imputation. For model development, multivariable Cox proportional hazards regression analysis was performed. To test whether candidate determinants contributed to the model, we performed backward selection using the Akaike information criterion. We corrected for overfitting using bootstrapping techniques. The performance of the model was assessed using discrimination and calibration. RESULTS: A total of 182 patients were included (mean age, 43.0 ± 19.7 years). Independent determinants of cranioplasty implant survival included the indication for craniectomy (compared with trauma-vascular disease: hazard ratio [HR], 0.65 [95% confidence interval (CI), 0.36-1.17]; infection: HR, 0.76 [95% CI, 0.32-1.80]; tumor: HR, 1.40 [95% CI, 0.29-6.79]), cranial defect size (HR, 1.01 per cm2 [95% CI, 0.73-1.38]), use of an autologous bone flap (HR, 1.63 [95% CI, 0.82-3.24]), and skin closure using staples (HR, 1.42 [95% CI, 0.79-2.56]). The concordance index of the model was 0.60 (95% CI, 0.47-0.73). CONCLUSIONS: We have developed the first prediction model for cranioplasty implant survival after craniectomy. The findings from our study require external validation and deserve further exploration in future studies.


Assuntos
Craniectomia Descompressiva , Procedimentos de Cirurgia Plástica , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Retalhos Cirúrgicos/cirurgia , Estudos Retrospectivos , Craniectomia Descompressiva/métodos , Crânio/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia
3.
Bioinformation ; 19(13): 1307-1311, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38415041

RESUMO

It is of interest to compare guided bone regeneration (GBR) with titanium mesh, alveolar distraction osteo-genesis (DO), GBR with auto-genous bone and e-PTFE membranes and onlay bone grafts. This helps to restore vertically lacking alveolar ridges and their capacity to sustain the vertical bone growth acquired both prior to and following implant placement. The parameters such as (i) success and survival of dental implants (ii) peri-implant clinical parameters after prosthetic loading at 1 year, 2 year and 3 year follow up (iii) resorption of alveolar ridge regenerated before placement of dental implants and after placement of dental implants were assessed. Data shows that the distraction osteo-genesis is more predictable for long-term prognosis of vertical bone growth. However, all methods help to repair the vertically resorbed edentulous ridges.

4.
BMC Oral Health ; 22(1): 24, 2022 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-35094679

RESUMO

BACKGROUND: The objective was to assess whether intraoral bone augmentation procedures have an impact on the patient's plasma levels of circulating nucleic acids, exosomes, miRNA levels and caspase activities. The null hypothesis was tested, that no significant differences between the two groups will be found. METHODS: In this prospective randomized controlled clinical trial 35 systemically healthy non-smoking participants were randomly allocated using sealed envelopes by a blinded clinician not involved in the clinical setting. Plasma samples were collected preoperatively and 3 times postoperatively (immediately, 5 weeks and 4 months postoperatively). The test group consisted of twenty-five patients who received allogeneic bone grafting material and the control group of ten patients who received autologous bone grafts. Levels of cell-free DNA (cfDNA) and microRNAs (miR-21, miR-27a, miR-218) were quantified by real-time PCR, caspase activities and exosome concentrations were determined by ELISA. RESULTS: Statistical evaluation reveled a significantly higher exosome level before surgery (p = 0.013) and the first postsurgical sample (p = 0.017) in the control group compared to the test group. The levels of miR-27a and miR-218 significantly differed between the plasma samples before surgery and after surgery in both groups. The levels of miR-21 only significantly differed between the pre- and postsurgical plasma samples in the test group, but not in the control group. All patients completed the study, no adverse events were recorded. CONCLUSIONS: Our data show the diagnostic potential of the plasma levels of miR-27a, miR-218 and miR-21 in detecting changes in bone metabolism after alveolar bone augmentation. Our very promising results indicate that there might be a high diagnostic potential in evaluating the plasma levels of the before mentioned miRNAs in order to detect bone resorption activities before they become clinically relevant. Trial registration Ethical commission of the Ärztekammer Hamburg, Germany (PV5211) on 11/03/2016 as well as by the German Registry of Clinical Studies (DRKS 00,013,010) on 30/07/2018 ( http://apps.who.int/trialsearch/ ).


Assuntos
Exossomos , Transplante de Células-Tronco Hematopoéticas , MicroRNAs , Transplante Ósseo , Exossomos/genética , Exossomos/metabolismo , Humanos , MicroRNAs/metabolismo , Transplante Autólogo
5.
J Pharm Bioallied Sci ; 12(Suppl 1): S394-S398, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33149493

RESUMO

Reconstruction of craniofacial bony defects has always been a challenging task for the surgeons over the years. The science of reconstructing such defects is of at most importance to craniofacial and plastic surgeons due to its relevance in facial aesthetics function as well as prerequisite procedure for continuing other surgical procedures. The main goal of the reconstruction of the craniofacial defects is to reduce the morbidity by restoring the facial form and aesthetics, as well as a good function of the facial structures by achieving a reasonable occlusion and articulation. Although significant improvements have occurred during the last few decades, challenges still exist as to what type of reconstruction to be carried out with regard to techniques and the type and quality of materials of choice to be used. As decades progressed, the advancement in surgical techniques and the variety of reconstruction methods have definitely improved the quality of life. This article reviews the method of bony reconstruction of craniofacial defects using autologous human bone marrow stem cells and autologous bone grafts and its modification, which includes much recent tissue engineering techniques and regenerative medicine, thereby replacing older techniques by biological substitutes, which can restore improve and maintain orofacial function and aesthetics.

6.
Rev. medica electron ; 42(5): 2366-2377, sept.-oct. 2020.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1144740

RESUMO

RESUMEN El material de elección para el reemplazo del hueso perdido por traumatismos, procesos patológicos congénitos o adquiridos y atrofia, son los injertos óseos autógenos o autólogos (hueso del propio paciente). A partir de la introducción del concepto de osteointegración por Branemark, los implantes dentales son parte de la terapéutica diaria para rehabilitar áreas edéntulas. La atrofia alveolar es quizás una de las condiciones bucales más incapacitantes; la razón reside en que es crónica, progresiva, acumulativa e irreversible, altera las relaciones maxilomandibulares, reduce la cantidad de hueso del área dentosoportada y la profundidad del surco. El material de injerto óseo ideal no debería ser sólo un sustituto óseo, sino un material de regeneración que se reabsorba completamente de modo simultáneo a la formación de hueso nuevo. Evaluar el éxito y fracaso de una terapia permite tomar decisiones para un mejoramiento continuo de la práctica clínica. El objetivo de la investigación fue demostrar la importancia de la utilización de biomateriales e injertos óseos autólogos en pacientes con atrofia alveolar (AU).


SUMMARY The elective material for replacing the bone lost by trauma, congenital or acquired pathological processes and atrophy are the autogenic or autologous bone grafts (the patient´s own bones). From the introduction of the concept of osseointegration by Branemark on, dental implants are part of the daily therapeutic for rehabilitating edentulous areas. Alveolar atrophy is perhaps one of the most disabling oral conditions, because it is chronic, progressive, cumulative and irreversible. It alters maxilla-mandibular relations, reduces the bone quality of the dentosupported area and the depth of the sulcus. The ideal bone graft material should not be only a bone substitute, by a regenerative material that could be completely reabsorbed simultaneously with the new bone formation. To assess the success and failure of a therapy allows taking decisions for the continuous improvement of the clinical practice. The aim of the research was to prove the importance of using biomaterials or autologous bone grafts in patients with alveolar atrophy (AU).


Assuntos
Humanos , Masculino , Feminino , Doenças Periodontais/terapia , Atrofia/diagnóstico , Materiais Biocompatíveis/uso terapêutico , Prótese Dentária/métodos , Procedimentos de Cirurgia Plástica , Transplantes
7.
Br J Neurosurg ; 34(4): 388-396, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32233810

RESUMO

Objective: Meta-analysis to evaluate complications in the use of autogenous bone and bone substitutes and to compare bone substitutes, specifically HA, polyetheretherketone (PEEK) and titanium materials.Methods: Search of PubMed, Cochrane, Embase and Google scholar to identify all citations from 2010 to 2019 reporting complications regarding materials used in cranioplasty.Results: 20 of 2266 articles met the inclusion criteria, including a total of 2913 patients. The odds of overall complication were significantly higher in the autogenous bone group (n = 214/644 procedures, 33.2%) than the bone substitute groups (n = 116/436 procedures, 26.7%, CI 1.29-2.35, p < 0.05). In bone substitutes groups, there was no significant difference in overall complication rate between HA and Ti (OR, 1.2; 95% CI, 0.47-3.14, p = 0.69). PEEK has lower overall complication rates (OR, 0.51; 95% CI, 0.30-0.87, p = 0.01) and lower implant exposure rates (OR, 0.17; 95% CI, 0.06-0.53, p = 0.002) than Ti, but there was no significant difference in infection rates and postoperative hematoma rates.Conclusions: Cranioplasty is associated with high overall complication rates with the use of autologous bone grafts compared with bone substitutes. PEEK has a relatively low overall complication rates in substitutes groups, but still high infection rates and postoperative hematoma rates. Thus, autologous bone grafts should only be used selectively, and prospective long-term studies are needed to further refine a better material in cranioplasty.


Assuntos
Procedimentos de Cirurgia Plástica , Crânio/cirurgia , Transplante Ósseo , Humanos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Próteses e Implantes/efeitos adversos
8.
Rev. medica electron ; 41(6): 1424-1437, oct.-dic. 2019. tab
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1094140

RESUMO

RESUMEN Introducción: los injertos óseos constituyen una de las técnicas más utilizadas en la cirugía reconstructiva implantológicas, son muy utilizadas para el reemplazo del hueso perdido por traumatismos, procesos patológicos congénitos o adquiridos y atrofia, son los injertos óseos autógenos o autólogos. Objetivo: caracterizar los pacientes con rebordes atróficos que necesitaron ser rehabilitados en implantología oral como alternativa de tratamiento en la consulta de Cirugía Máxilo Facial del Hospital Universitario "Faustino Pérez" y la Clínica "III Congreso del PCC", municipio Matanzas de septiembre del 2014 a julio de 2016. Material y Método: estudio prospectivo longitudinal. El universo fue de 20 pacientes mayores de 18 años de ambos sexos, que presentaron el diagnóstico de edentulismo parcial y atrofia alveolar. Se determinó por el interrogatorio, el examen clínico y los medios diagnósticos los síntomas y signos que caracterizaron esta entidad. Resultados: los traumatismos alveolares fue la causa que predominó en la pérdida dentaria, en el sexo masculino y en las edades de 18 a 37 años. La zona de mayor afectación fue la región anterior del maxilar superior y predominó la perdida de hueso en altura y en anchura y un gran número de injertos conservaron la cresta alveolar. Conclusiones: el uso de biomateriales en el tratamiento de pacientes con atrofia alveolar junto al injerto óseo fue satisfactorio en pacientes que necesitaron una base de sostén sobre la cual se colocaron los implantes dentales osteointegrados (AU).


SUMMARY Introduction: autogenous and autologous bone grafts are the elective material for replacing bones lost by trauma, congenital or acquired pathologic processes and atrophy. Objective: to characterize patients with atrophic rims needing rehabilitation in oral grafting as an alternative treatment in the Maxilla-Facial Surgery consultation of the University Hospital "Faustino Perez" and the Clinic "III Congreso del PCC", municipality of Matanzas, from September 2014 to July 2016. Materials and Methods: longitudinal prospective study. The universe was 20 patients aged 18 years and older, males and females, who presented the diagnosis of partial lack of teeth and alveolar atrophy. The symptoms and signs characterizing this entity were stated by questioning, physical examination and diagnostic means. Results: alveolar traumas were the predominant cause of dental lost in male patients aged 18-37 years. The most affected zone was the anterior region of the upper maxilla; bone lost in height and width predominated, and a great number of grafts conserved the alveolar crest. Conclusions: the use of biomaterials in the treatment of patients with alveolar atrophy together with bone graft was satisfactory in patients who needed a base support on which to put dental grafts (AU).


Assuntos
Humanos , Criança , Adolescente , Processo Alveolar/patologia , Aumento do Rebordo Alveolar , Alveolectomia , Enxerto de Osso Alveolar , Reabilitação , Atrofia/diagnóstico , Atrofia/etiologia , Atrofia/epidemiologia , Cirurgia Bucal , Epidemiologia Descritiva , Estudos Transversais , Estudo Observacional
9.
J Hand Surg Am ; 44(1): 60.e1-60.e8, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29934078

RESUMO

PURPOSE: Fragmentation of the scaphoid proximal pole secondary to avascular necrosis presents a difficult reconstructive problem. This anthropometric study assesses the utility of the ipsilateral proximal hamate for complete osteochondral scaphoid proximal pole reconstruction. METHODS: Twenty-nine cadaveric specimens underwent computed tomography scanning and 3-dimensional reconstruction of the carpus and distal radius. Scaphoid height was measured and a third of its height was used to simulate resection of the proximal scaphoid pole and extent of hamate autograft required. The proximal scaphoid and hamate were divided into 6 sections, and compared using an iterative point-to-point distance algorithm. Average distance between the scaphoid and the hamate surfaces was determined. An interbone algorithm was used to assess radioscaphoid joint congruency and articular contact surface of the native scaphoid compared with the scaphoid reconstructed with hamate autograft. RESULTS: The mean height of scaphoid proximal pole excision and proximal hamate autograft height was 9.3 mm. Comparing the morphology of the native scaphoid and hamate autografts, the absolute distances were the largest in the volar radioscaphoid, dorsal radioscaphoid, and dorsal scaphocapitate segments. Without osteotomy, the hamate autograft may cause impaction in the dorsal-radial aspect of the distal radius. The hamate autograft also shifted the articular contact point of the radioscaphoid joint toward the dorsal-radial position. Nine hamate autografts were classified as poor-fitting. Poor-fitting specimens had a greater radial styloid to distal radioulnar joint distance. These specimens also had wider hamates and scaphoids in the radial-ulnar dimension and wider scaphoids in the volar-dorsal dimension. Lunate type did not correspond to anthropometric fit. CONCLUSIONS: The proximal hamate osteochondral graft was poor fitting in 31% of cases (9 of 29 specimens). Wrists with radial-ulnar hamate width less than 10 mm, radial-ulnar scaphoid width less than 10 mm, and volar-dorsal scaphoid width less than 16 mm demonstrate better anthropometric fit. CLINICAL RELEVANCE: This study provides an anthropometric assessment of the recently described proximal hamate autograft, a new bone graft option for proximal scaphoid pole reconstruction.


Assuntos
Autoenxertos , Hamato/anatomia & histologia , Hamato/transplante , Osso Escafoide/anatomia & histologia , Osso Escafoide/cirurgia , Idoso , Algoritmos , Antropometria , Cadáver , Articulações do Carpo/anatomia & histologia , Articulações do Carpo/diagnóstico por imagem , Feminino , Hamato/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Masculino , Osteotomia , Osso Escafoide/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Articulação do Punho/anatomia & histologia , Articulação do Punho/diagnóstico por imagem
10.
Clin Oral Implants Res ; 28(12): 1484-1491, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28382633

RESUMO

OBJECTIVE: To compare the sequential healing at the interface gap occurring between autologous bone grafts and recipient sites using two types of fixation techniques. MATERIAL AND METHODS: Twenty-four adult male New Zealand white rabbits were used. Two bone grafts were collected from the calvaria and secured to the lateral aspect of the angle of mandible in each animal. Cortical perforations at the recipient sites were performed. However, no modifications were applied to the graft for its adaptation to the recipient site. Two types of fixation techniques by position or lag screws were applied. This was done by preparing osteotomy holes smaller or larger than the screw diameter, respectively. The animals were sacrificed after 3, 7, 20, and 40 days. RESULTS: After 3 days, the distance between the graft and the recipient site was similar between the two different fixations. Due to the anatomical shapes of the recipient sites and grafts, the distance between the two parts was lower in the central region (<0.1 mm) compared to the external regions of the graft (0.5-0.6 mm). The first evidence of small amounts of new (woven) bone was seen after 7 days, forming from the parent bone. The percentage increased after 20 and 40 days. After 40 days, the grafts were well incorporated within the recipient sites in both groups without any statistically significant difference. CONCLUSIONS: The present study did not show superiority of one method over another. A fixation to a recipient site with perforations may be sufficient for incorporating an autologous bone graft even if its adaptation is not perfect and irrespectively of the fixation method. Distances of approximately half millimeter were bridged with newly formed bone.


Assuntos
Parafusos Ósseos , Mandíbula/cirurgia , Crânio/transplante , Cicatrização , Animais , Osteotomia , Coelhos , Titânio , Transplante Autólogo
11.
J Orthop Surg Res ; 11(1): 105, 2016 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-27669690

RESUMO

BACGROUND: Although the contribution of fibroblast growth factor (FGF)-2 and mesenchymal stromal cells (MSCs) to bone formation is well known, few studies have investigated the combination of an autologous bone graft with FGF-2 or MSCs for large bone defects. METHODS: We studied an atrophic non-union model with a large bone defect, created by resecting a 10-mm section from the center of each femoral shaft of 12-week-old Sprague-Dawley rats. The periosteum of the proximal and distal ends of the femur was cauterized circumferentially, and excised portions were used in the contralateral femur as autologous bone grafts. The rats were randomized to three groups and given no further treatment (group A), administered FGF-2 at 20 µg/20 µL (group B), or 1.0 × 106 MSCs (group C). Radiographs were taken every 2 weeks up to 12 weeks, with CT performed at 12 weeks. Harvested femurs were stained with toluidine blue and evaluated using radiographic and histology scores. RESULTS: Radiographic and histological evaluation showed that bone union had been achieved at 12 weeks in group C, while group B showed callus formation and bridging callus but non-union, and in group A, callus formation alone was evident. Both radiographic and histological scores were significantly higher at 2, 4, 6, 8, 10, and 12 weeks in groups B and C than group A and also significantly higher in group C than group B at 12 weeks. CONCLUSIONS: These data suggest that autologous bone grafts in combination with MSCs benefit difficult cases which cannot be treated with autologous bone grafts alone.

12.
Clin Implant Dent Relat Res ; 17(6): 1188-99, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26010600

RESUMO

PURPOSE: To compare five different implant treatment protocols in the anterior maxilla, including immediate, early, and delayed implant placement, as well as implant placement in conjunction with simultaneous guided bone regeneration and implant placement 3 months following horizontal autologous bone block grafting. MATERIAL AND METHODS: Aesthetic indices used included the Pink Esthetic Score (PES), Papilla Index (PI), Subjective Esthetic Score (SES), and White Esthetic Score (WES). Subjective evaluation of implant aesthetics was performed using a visual analogue scale (VAS). The VAS consisted of a 10 cm-long line representing the degree of discontent (0%) or satisfaction (100%). RESULTS: A total of 153 implants in 153 patients (80 women, 73 men) were evaluated after a mean follow-up of 4.5 ± 2.9 years. Mean peri-implant bone loss was 1.6 ± 0.9 mm and not affected by treatment protocol, time after implant placement, or crown length. Papilla presence, by contrast, differed significantly between the protocols: Papilla formation was more pronounced following delayed and immediate implant placement. No statistical significance was found among treatment modalities with regard to PES, SES, or WES. Longer crowns were associated with lower PES and PI ratings and correlated with greater midfacial recession. SES was also influenced by time after implant placement and keratinized mucosa. Patient satisfaction differed significantly among treatment protocols, favoring immediate implant placement. Agreement between objective and subjective aesthetic ratings was low. CONCLUSION: The present study suggests that comparable clinical, radiological, and aesthetic results can be achieved with all treatment protocols. Gingival recession, however, seems to occur in the long term irrespective of the technique used.


Assuntos
Transplante Ósseo/métodos , Implantação Dentária Endóssea/métodos , Implantes Dentários para Um Único Dente , Estética Dentária , Regeneração Tecidual Guiada/métodos , Adulto , Diagnóstico por Imagem , Feminino , Seguimentos , Humanos , Masculino , Satisfação do Paciente , Fatores de Tempo , Resultado do Tratamento
13.
Int J Oral Maxillofac Surg ; 44(9): 1131-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25979191

RESUMO

The aim of this study was to evaluate the morbidity following bone harvesting at two different intraoral donor sites, mandibular symphysis and ramus, and to determine the effects of piezoelectric and conventional surgical graft harvesting techniques on donor site morbidity. Intraoral block bone grafts were harvested from the symphysis (n=44) and ramus (n=31). The two donor site groups were divided into two subgroups according to the surgical graft harvesting method used (conventional or piezoelectric surgery). Intraoperative and postoperative pain was assessed using a visual analogue scale (VAS). Donor site morbidity and the harvesting techniques were compared statistically. Of 290 teeth evaluated in the symphysis group, four needed root canal treatment after surgery. The incidence of transient paresthesia in the mucosa was significantly higher in the symphysis group than in the ramus group (P=0.004). In the symphysis group, the incidence of temporary skin and mucosa paresthesia was lower in the piezoelectric surgery subgroup than in the conventional surgery subgroup (P=0.006 and P=0.001, respectively). No permanent anaesthesia of any region of the skin was reported in either donor site group. VAS scores did not differ between the ramus and symphysis harvesting groups, or between the piezoelectric and conventional surgery subgroups. When the symphysis was chosen as the donor site, minor sensory disturbances of the mucosa and teeth were recorded. The use of piezoelectric surgery during intraoral harvesting of bone blocks, especially from the symphysis, can reduce these complications.


Assuntos
Mandíbula/cirurgia , Piezocirurgia , Coleta de Tecidos e Órgãos/efeitos adversos , Sítio Doador de Transplante/patologia , Adolescente , Adulto , Idoso , Transplante Ósseo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Complicações Pós-Operatórias , Estudos Prospectivos
14.
Clin Implant Dent Relat Res ; 17(5): 938-49, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24461197

RESUMO

BACKGROUND AND PURPOSE: Autografts are used for bone reconstruction in regenerative medicine including oral and maxillofacial surgery. Bone grafts release paracrine signals that can reach mesenchymal cells at defect sites. The impact of the paracrine signals on osteogenic, adipogenic, and chondrogenic differentiation of mesenchymal cells has remained unclear. MATERIAL AND METHODS: Osteogenesis, adipogenesis, and chondrogenesis were studied with murine ST2 osteoblast progenitors, 3T3-L1 preadipocytes, and ATDC5 prechondrogenic cells, respectively. Primary periodontal fibroblasts from the gingiva, from the periodontal ligament, and from bone were also included in the analysis. Cells were exposed to bone-conditioned medium (BCM) that was prepared from porcine cortical bone chips. RESULTS: BCM inhibited osteogenic and adipogenic differentiation of ST2 and 3T3-L1 cells, respectively, as shown by histological staining and gene expression. No substantial changes in the expression of chondrogenic genes were observed in ATDC5 cells. Primary periodontal fibroblasts also showed a robust decrease in alkaline phosphatase and peroxisome proliferator-activated receptor gamma (PPARγ) expression when exposed to BCM. BCM also increased collagen type 10 expression. Pharmacologic blocking of transforming growth factor (TGF)-ß receptor type I kinase with SB431542 and the smad-3 inhibitor SIS3 at least partially reversed the effect of BCM on PPARγ and collagen type 10 expression. In support of BCM having TGF-ß activity, the respective target genes were increasingly expressed in periodontal fibroblasts. CONCLUSIONS: The present work is a pioneer study on the paracrine activity of bone grafts. The findings suggest that cortical bone chips release soluble signals that can modulate differentiation of mesenchymal cells in vitro at least partially involving TGF-ß signaling.


Assuntos
Adipogenia , Osso e Ossos/citologia , Condrogênese , Meios de Cultivo Condicionados/farmacologia , Células-Tronco Mesenquimais/citologia , Osteogênese , Animais , Transplante Ósseo , Fibroblastos/citologia , Camundongos , Osteoblastos/citologia , Ligamento Periodontal/citologia , Suínos
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