Marine spongin incorporation into Biosilicate® for tissue engineering applications: An in vivo study.

Biomaterials and bone grafts, with the ability of stimulating tissue growth and bone consolidation, have been emerging as very promising strategies to treat bone fractures. Despite its well-known positive effects of biosilicate (BS) on osteogenesis, its use as bone grafts in critical situations such as bone defects of high dimensions or in non-consolidated fractures may not be sufficient to stimulate tissue repair. Consequently, several approaches have been explored to improve the bioactivity of BS. A promising strategy to reach this aim is the inclusion of an organic part, such as collagen, in order to mimic bone structure. Thus, the present study investigated the biological effects of marine spongin (SPG)-enriched BS composites on the process of healing, using a critical experimental model of cranial bone defect in rats. Histopathological and immunohistochemistry analyzes were performed after two and six weeks of implantation to investigate the effects of the material on bone repair (supplemental material-graphical abstract). Histological analysis demonstrated that for both BS and BS/SPG, similar findings were observed, with signs of material degradation, the presence of granulation tissue along the defect area and newly formed bone into the area of the defect. Additionally, histomorphometry showed that the control group presented higher values for Ob.S/BS (%) and for N.Ob/T.Ar (mm2) (six weeks post-surgery) compared to BS/SPG and higher values of N.Ob/T.Ar (mm2) compared to BS (two weeks post-surgery). Moreover, BS showed higher values for OV/TV (%) compared to BS/SPG (six weeks post-surgery). Also, VEGF immunohistochemistry was increased for BS (two weeks post-surgery) and for BS/SPG (six weeks) compared to CG. TGFb immunostaining was higher for BS compared to CG. The results of this study demonstrated that the BS and BS/SPG scaffolds were biocompatible and able to support bone formation in a critical bone defect in rats. Moreover, an increased VEGF immunostaining was observed in BS/SPG.

Bone regeneration in Ds-Red pig calvarial defect using allogenic transplantation of EGFP-pMSCs - A comparison of host cells and seeding cells in the scaffold.

BACKGROUND: Cells, scaffolds, and factors are the triad of regenerative engineering; however, it is difficult to distinguish whether cells in the regenerative construct are from the seeded cells or host cells via the host blood supply. We performed a novel in vivo study to transplant enhanced green fluorescent pig mesenchymal stem cells (EGFP-pMSCs) into calvarial defect of DsRed pigs. The cell distribution and proportion were distinguished by the different fluorescent colors through the whole regenerative period. METHOD/RESULTS: Eight adult domestic Ds-Red pigs were treated with five modalities: empty defects without scaffold (group 1); defects filled only with scaffold (group 2); defects filled with osteoinduction medium-loaded scaffold (group 3); defects filled with 5 x 103 cells/scaffold (group 4); and defects filled with 5 x 104 cells/scaffold (group 5). The in vitro cell distribution, morphology, osteogenic differentiation, and fluorescence images of groups 4 and 5 were analyzed. Two animals were sacrificed at 1, 2, 3, and 4 weeks after transplantation. The in vivo fluorescence imaging and quantification data showed that EGFP-pMSCs were represented in the scaffolds in groups 4 and 5 throughout the whole regenerative period. A higher seeded cell density resulted in more sustained seeded cells in bone regeneration compared to a lower seeded cell density. Host cells were recruited by seeded cells if enough space was available in the scaffold. Host cells in groups 1 to 3 did not change from the 1st week to 4th week, which indicates that the scaffold without seeded cells cannot recruit host cells even when enough space is available for cell ingrowth. The histological and immunohistochemical data showed that more cells were involved in osteogenesis in scaffolds with seeded cells. CONCLUSION: Our in vivo results showed that more seeded cells recruit more host cells and that both cell types participate in osteogenesis. These results suggest that scaffolds without seeded cells may not be effective in bone transplantation.

Investigation of the effects of semaphorin 3A on new bone formation in a rat calvarial defect model.

PURPOSE: This study investigates the effects of semaphorin 3A on new bone formation in an experimental rat model. MATERIALS AND METHODS: Cortical bone defects, 5 mm, were created in the calvaria of 40 Wistar rats, which were then separated into three groups: empty defect (control) group, collagen group, collagen + semaphorin 3A group. The bone blocks were harvested after 4 and 8 weeks. New bone formation was assessed by micro-computed tomography (micro-CT), histology, histomorphometry, transmission electron microscope (TEM) and immunohistochemistry. RESULTS: Increased bone formation was observed in collagen + semaphorin 3A groups both histologically and with micro-CT. In the histomorphometic analysis, the control group had significantly less bone formation compared to both the collagen and collagen + semaphorin 3A group at 4 weeks (p = 0.0001) and 8 weeks (p = 0.0001). The collagen group had significantly less bone formation compared to collagen + semaphorin 3A group both at 4 weeks (p = 0.002) and 8 weeks (p = 0.005). Immunohistochemical analysis revealed that semaphorin 3A inhibited receptor activator of nuclear factor-kB ligand (RANKL) expression and increased the expressions of osteoblastic bone markers at 4 weeks. In TEM analysis, the collagen + semaphorin 3A group had an increased proliferation and bone formation rate at 4 weeks, whereas bone quantity and maturation were enhanced at 8 weeks. CONCLUSION: Locally applied semaphorin 3A increases callus formation at 4 weeks and bone formation at 8 weeks. Semaphorin 3A prevents bone resorption by inhibiting osteoclasts and increases bone formation by inducing osteoblasts.

Direct vascular channels connect skull bone marrow and the brain surface enabling myeloid cell migration.

Innate immune cells recruited to inflammatory sites have short life spans and originate from the marrow, which is distributed throughout the long and flat bones. While bone marrow production and release of leukocyte increases after stroke, it is currently unknown whether its activity rises homogeneously throughout the entire hematopoietic system. To address this question, we employed spectrally resolved in vivo cell labeling in the murine skull and tibia. We show that in murine models of stroke and aseptic meningitis, skull bone marrow-derived neutrophils are more likely to migrate to the adjacent brain tissue than cells that reside in the tibia. Confocal microscopy of the skull-dura interface revealed myeloid cell migration through microscopic vascular channels crossing the inner skull cortex. These observations point to a direct local interaction between the brain and the skull bone marrow through the meninges.

Structural and ultrastructural analyses of bone regeneration in rabbit cranial osteotomy: Piezosurgery versus traditional osteotomes.

Clinical advantages of piezosurgery have been already proved. However, few investigations have focused on the dynamics of bone healing. The aim of this study was to evaluate, in adult rabbits, bone regeneration after cranial linear osteotomies with two piezoelectrical devices (Piezosurgery® Medical - PM and Piezosurgery® Plus - PP), comparing them with conventional rotary osteotomes (RO). PP was characterized by an output power three times higher than PM. Fifteen days after surgery, histomorphometric analyses showed that the osteotomy gap produced with PM and PP was about half the size of that produced by RO, and in a more advanced stage of recovery. Values of regenerated bone area with respect to the total osteotomy area were about double in PM and PP samples compared with RO ones, while the number of TRAP-positive (tartrate-resistant acid phosphatase positive) osteoclasts per linear surface showed a significant increase, suggesting greater bone remodelling. Under scanning electron microscopy, regenerated bone displayed higher cell density and less mineralized matrix compared with pre-existent bone for all devices used. Nanoindentation tests showed no changes in elastic modulus. In conclusion, PM/PP osteotomies can be considered equivalent to each other, and result in more rapid healing compared with those using RO.

Chitosan-Graphene Oxide 3D scaffolds as Promising Tools for Bone Regeneration in Critical-Size Mouse Calvarial Defects.

Limited self-regenerating capacity of human skeleton makes the reconstruction of critical size bone defect a significant challenge for clinical practice. Aimed for regenerating bone tissues, this study was designed to investigate osteogenic differentiation, along with bone repair capacity of 3D chitosan (CHT) scaffolds enriched with graphene oxide (GO) in critical-sized mouse calvarial defect. Histopathological/histomorphometry and scanning electron microscopy(SEM) analysis of the implants revealed larger amount of new bone in the CHT/GO-filled defects compared with CHT alone (p < 0.001). When combined with GO, CHT scaffolds synergistically promoted the increase of alkaline phosphatase activity both in vitro and in vivo experiments. This enhanced osteogenesis was corroborated with increased expression of bone morphogenetic protein (BMP) and Runx-2 up to week 4 post-implantation, which showed that GO facilitates the differentiation of osteoprogenitor cells. Meanwhile, osteogenesis was promoted by GO at the late stage as well, as indicated by the up-regulation of osteopontin and osteocalcin at week 8 and overexpressed at week 18, for both markers. Our data suggest that CHT/GO biomaterial could represent a promising tool for the reconstruction of large bone defects, without using exogenous living cells or growth factors.

Postnatal Calvarial Skeletal Stem Cells Expressing PRX1 Reside Exclusively in the Calvarial Sutures and Are Required for Bone Regeneration.

Post-natal skeletal stem cells expressing PRX1 (pnPRX1+) have been identified in the calvaria and in the axial skeleton. Here we characterize the location and functional capacity of the calvarial pnPRX1+ cells. We found that pnPRX1+ reside exclusively in the calvarial suture niche and decrease in number with age. They are distinct from preosteoblasts and osteoblasts of the sutures, respond to WNT signaling in vitro and in vivo by differentiating into osteoblasts, and, upon heterotopic transplantation, are able to regenerate bone. Diphtheria toxin A (DTA)-mediated lineage ablation of pnPRX1+ cells and suturectomy perturb regeneration of calvarial bone defects and confirm that pnPRX1+ cells of the sutures are required for bone regeneration. Orthotopic transplantation of sutures with traceable pnPRX1+ cells into wild-type animals shows that pnPRX1+ cells of the suture contribute to calvarial bone defect regeneration. DTA-mediated lineage ablation of pnPRX1+ does not, however, interfere with calvarial development.

Enhanced osteoconductivity of polyethersulphone nanofibres loaded with bioactive glass nanoparticles in in vitro and in vivo models.

OBJECTIVES: There is growing need for new scaffold constructions for synthetic bone graft substitutes to repair large bone lesions. A very promising and important class of new implants for tissue engineering is based on three-dimensional scaffolds and bioceramics. MATERIALS AND METHODS: In this study, after investigation of mechanical properties of polyethersulphone (PES) nanofibres, fabricated by electrospinning methodology and coated with bioactive glass (BG), cells of the MG-63 line were cultured on surfaces of these scaffolds. Their capacity to support MG-63 proliferation was also investigated in vitro by MTT assay. Osteoconductivity on these scaffolds was investigated by the common osteogenic markers alkaline phosphatase (ALP) activity, calcium mineral deposition and bone-related gene activation. Next, a bone reconstruction of rat critical-size defects model was evaluated using radiographic imaging analysis (digital mammography), computed tomography and histological examination. RESULTS: In vitro results indicated that biocompatibility and osteogenic markers of MG-63 cells were significantly enhanced after coating PES with BG. Based on in vivo results, new bone formation in the defect site was enhanced in implanted rats in comparison with a control group. The highest reconstruction was observed in animals implanted with BG-coated nanofibres. CONCLUSIONS: Osteoconductivity of PES nanofibres was markedly enhanced after coating them with BG, and introduction of this construct as new bone-graft substitute for bone loss and defects is indicated.

Effects of Immobilized BMP-2 and Nanofiber Morphology on In Vitro Osteogenic Differentiation of hMSCs and In Vivo Collagen Assembly of Regenerated Bone.

Engineering bone tissue is particularly challenging because of the distinctive structural features of bone within a complex biochemical environment. In the present study, we fabricated poly(L-lactic acid) (PLLA) electrospun nanofibers with random and aligned morphology immobilized with bone morphogenic protein-2 (BMP-2) and investigated how these signals modulate (1) in vitro osteogenic differentiation of human mesenchymal stem cells (hMSCs) and (2) in vivo bone growth rate, mechanical properties, and collagen assembly of newly formed bone. The orientation of adherent cells followed the underlying nanofiber morphology; however, nanofiber alignment did not show any difference in alkaline phosphate activity or in calcium mineralization of hMSCs after 14 days of in vitro culture in osteogenic differentiation media. In vivo bone regeneration was significantly higher in the nanofiber implanted groups (approximately 65-79%) as compared to the defect-only group (11.8 ± 0.2%), while no significant difference in bone regeneration was observed between random and aligned groups. However, nanoindentation studies of regenerated bone revealed Young's modulus and contact hardness with anisotropic feature for aligned group as compared to random group. More importantly, structural analysis of collagen at de novo bone showed the ability of nanofiber morphology to guide collagen deposition. SEM and TEM images revealed regular, highly ordered collagen assemblies on aligned nanofibers as compared to random fibers, which showed irregular, randomly organized collagen deposition. Taken together, we conclude that nanofibers in the presence of osteoinductive signals are a potent tool for bone regeneration, and nanofiber alignment can be used for engineering bone tissues with structurally assembled collagen fibers with defined direction.

Intravital multiphoton microscopy for dissecting cellular dynamics in arthritic inflammation and bone destruction.

Osteoclasts are giant bone-resorbing polykaryons that differentiate from mononuclear macrophage/monocyte-lineage hematopoietic precursors. They play critical roles not only in normal bone homeostasis (remodeling) but also in the pathogenesis of bone-destructive disorders such as osteoporosis and rheumatoid arthritis. However, how the activity of mature osteoclasts is regulated in vivo remains unclear. To answer this question, we recently developed an advanced imaging system to visualize living bone tissues with intravital multiphoton microscopy. Using this system, we succeeded in visualization of mature osteoclasts in living bones. We herein describe the detailed methodology for visualizing bone resorption of mature osteoclasts in living bone marrow and joints using intravital multiphoton microscopy. This approach would be beneficial for studying the cellular dynamics in arthritic inflammation and bone destruction in vivo and would thus be useful for evaluating novel anti-bone-resorptive drugs.

Comparison of three hydroxyapatite/ß-tricalcium phosphate/collagen ceramic scaffolds: an in vivo study.

Calcium-phosphate ceramics, which have a composition similar to bone mineral, represent a potentially interesting synthetic bone graft substitute. In the present study, three porous hydroxyapatite (HA)/ß-tricalcium phosphate (ß-TCP)/collagen ceramic scaffolds were developed, characterized, and tested for their bone repairing capacity and osteoinductive potential in a New Zealand Rabbit model. The ratio of the ceramic components HA/-TCP/collagen varied from 40/30/30 to 50/20/30 and 60/20/20 (in wt %), respectively. None of the ceramic scaffolds succeeded in completely bridging the 6 mm calvarian defect with new bone after 60 days implantation. 60/20/20 ceramic scaffolds showed significantly more bone formation in the pores and in the periphery of the graft than the other two materials. Histomorphometric analysis revealed that the 40/30/30 scaffold produced best bone-to-implant contact (67.23 ± 0.34% with higher quality, closer contact) in comparison with 50/20/30 (54.87 ± 0.32%), and 60/20/20 (48.53 ± 0.31%). Both physicochemical and structural properties of the ceramic composites affected their in vivo behavior, either dependently or independently, emphasizing the importance of assessing bone repair parameters individually. The scaffolds may offer clinical applications in reconstructive surgery for treating bone pathologies.

Guidance of in vitro migration of human mesenchymal stem cells and in vivo guided bone regeneration using aligned electrospun fibers.

Tissue regeneration is a complex process in which numerous chemical and physical signals are coordinated in a specific spatiotemporal pattern. In this study, we tested our hypothesis that cell migration and bone tissue formation can be guided and facilitated by microscale morphological cues presented from a scaffold. We prepared poly(l-lactic acid) (PLLA) electrospun fibers with random and aligned structures and investigated their effect on in vitro migration of human mesenchymal stem cells (hMSCs) and in vivo bone growth using a critical-sized defect model. Using a polydopamine coating on the fibers, we compared the synergistic effects of chemical signals. The adhesion morphology of hMSCs was consistent with the direction of fiber alignment, whereas the proliferation of hMSCs was not affected. The orientation of fibers profoundly affected cell migration, in which hMSCs cultured on aligned fibers migrated 10.46-fold faster along the parallel direction than along the perpendicular direction on polydopamine-coated PLLA nanofibers. We implanted each fiber type into a mouse calvarial defect model for 2 months. The micro-computed tomography (CT) imaging demonstrated that regenerated bone area was the highest when mice were implanted with aligned fibers with polydopamine coating, indicating a positive synergistic effect on bone regeneration. More importantly, scanning electron microscopy microphotographs revealed that the direction of regenerated bone tissue appeared to be consistent with the direction of the implanted fibers, and transmission electron microscopy images showed that the orientation of collagen fibrils appeared to be overlapped along the direction of nanofibers. Taken together, our results demonstrate that the aligned nanofibers can provide spatial guidance for in vitro cell migration as well as in vivo bone regeneration, which may be incorporated as major instructive cues for the stimulation of tissue regeneration.

Comparison of microstructures between block grafts from the mandibular ramus and calvarium for horizontal bone augmentation of the maxilla: a case series study.

The primary purpose of this clinical study was to compare architectural metric parameters using microcomputed tomography (micro-CT) between sites grafted with blocks harvested from the mandibular ramus and calvarium for horizontal bone augmentation in the maxilla. The second aim was to compare the primary stability of implants placed in both types of block grafts. Ten consecutive healthy partially edentulous patients requiring extensive horizontal bone reconstruction in the maxilla were included. A total of 14 block grafts (7 each from the mandibular ramus and calvarium) were studied. After 4 to 6 months of healing, 41 implants were placed: 24 implants (58.5%) in calvarial (group 1) and 17 (41.5%) in ramus grafts (group 2). A resonance frequency analysis (RFA) was performed to test implant stability. Furthermore, two biopsy specimens were randomly selected for histomorphometric analysis. Micro-CT analyses showed no significant difference in the morphometric parametric values analyzed between groups. Furthermore, RFA also showed no difference between groups. However, slightly higher RFA values were noted for implants placed in ramus grafts. Bone quality, as assessed by micro-CT and histomorphometric analyses, was similar in both ramus and calvarial block grafts. In addition, there was no difference in primary implant stability between groups.

Skull invaders: when surgical pathology and neuropathology worlds collide.

Skull and dura serve as effective barriers to penetration by most tumors, often preventing masses originating intracranially from extending into the contiguous bone and soft tissues, or those arising in head and neck regions from extending into the dura and brain tissue. We review our 15-year experience with extracranial tumors that had sufficiently invaded adjacent skull, dura, or brain from the "outside-in" to require a neurosurgeon to participate in the surgical resection and discuss our 40 cases in context with the literature. Sinonasal-origin tumors (n = 17) and cutaneous tumors (n = 10) were the most frequent skull-invaders. Most of the cutaneous tumor types were squamous cellcarcinomas (n = 9); diverse sinonasal-origin types included 4 squamous cell carcinomas, 4 adenoid cystic carcinomas, 2 sinonasal undifferentiated carcinomas, 2 sinonasal adenocarcinomas, and single examples each of sinonasal-origin hemangiopericytoma, solitary fibrous tumor, melanoma, mucocele, and teratocarcinoma. There were 9olfactory neuroblastomas, and middle ear-origin basal cell carcinoma,recurrent glomus jugulare, and orbital malignant hidradenoma were also seen. Unique tumors included a cutaneous cylindroma invasive of skull convexity occurring in familial cylindromatosis and a ganglioneuroma of the middle ear with massive bilateral skull base extension. Convexity dural spread, a seldom-reported pattern of dissemination, was seen in 1 olfactory neuroblastoma and 1 adenoid cystic carcinoma. The ability to show skull/dural invasion did not correlate with specific histopathologic features; even benign tumor types can show skull/dural penetration.

Incorporation of stromal cell-derived factor-1α in PCL/gelatin electrospun membranes for guided bone regeneration.

The goal of this work was to evaluate the effect of membrane functionalization with a chemotactic factor on cell recruitment and bone formation in order to develop a bioactive membrane for guided bone regeneration (GBR) applications. To this end, GBR membranes were prepared by electrospinning using poly(ε-caprolactone) (PCL) blended with type B-gelatin, and functionalized with stromal cell derived factor-1α (SDF-1α) via physical adsorption. Firstly, the obtained membranes were evaluated in vitro for SDF-1α release and chemotactic effect on bone marrow stromal cells (BMSCs). Subsequently, in vivo BMSCs recruitment and bone regeneration in response to SDF-1α loaded PCL/gelatin electrospun membranes were assessed in rat cranial defects. The results showed that PCL/gelatin electrospun membranes provided a diffusion-controlled SDF-1α release profile. Furthermore, the membranes loaded with different amounts of SDF-1α (50-400 ng) significantly induced stimulated chemotactic migration of BMSCs in vitro without dose-dependent effects. Eight weeks after implantation in rat cranial defects, SDF-1α loaded membranes yielded a 6-fold increase in the amount of bone formation compared to the bare membranes, albeit that contribution of in vivo BMSCs recruitment to the bone regeneration could not be ascertained. In conclusion, the results of current study indicate the potential for using SDF-1α loaded PCL/gelatin electrospun membrane as a bioactive membrane, which is beneficial for optimizing clinical application of GBR strategies.

Association of mesenchymal stem cells with platelet rich plasma on the repair of critical calvarial defects in mice.

PURPOSE: To evaluate the effects of mesenchymal stem cells (MSC) from eight mice C57BL/6 gfp(+) bone marrows expanded in cultures associated with platelets rich plasma (PRP) deriving from another eight mice, in the repair of critical defects in calvarial bone produced in twenty-four adult isogenic mice C57BL/6. METHODS: The animals were submitted to a cranial defect of 6.0mm in diameter and divided into two equal experimental groups. Control group did not receive treatment and the treated group received a MSC pellet containing 1.0 x 10(7) cells/mL associated with 50.0 µL of plasma gel containing 1.0 x 10(9) autologous platelets within the defect. RESULTS: In the treated group was observed process of angiogenesis and bone repair better than control group. CONCLUSION: Mesenchymal stem cells derived from bone marrow of C57BL/6 gfp(+) mice associated with PRP gel applied in bone critical defects produced in calvarial contributes positively to the process of bone repair.

Comparative study of cranial capacity of the non-tribal with Korku Tribal population of Madhya Pradesh, India / Estudio comparativo de la capacidad craneal de población no-tribal con la Tribal Korku de Madhya Pradesh, India

Knowledge of cranial capacity is useful in differentiation of racial and sexual differences, which indirectly reflects the brain volume in different populations. Most of these studies have been done on the dry skulls using linear dimensions. Only few studies have been done on living subjects. The aim of this study was to compare cranial capacity of particular age group of Korku tribe & Non-tribal population of Madhya Pradesh a state of India. This study was carried on 800 healthy volunteer of 20 - 25 year-old age group (in which each 400 males and females) in Korku tribe and Non-tribal population of Madhya Pradesh state of India, by using linear dimensions of head (Lee Pearson's formula). The mean cranial capacity and SD in Non-tribal males and Non-tribal females were 1380.5 +/- 94.6 cc and 1188.7 +/- 91.1 cc, respectively. The mean cranial capacity and SD in Korku males and Korku females were 1212.2 +/- 62.0 cc and 1047.4 +/- 72.4, cc respectively. This study has shown a significant (p<0.05) difference between the same gender populations of Korku tribe and Non-tribal population, with the absolute values being higher in Non-tribal group than in Korku tribe group.

Conocer la capacidad craneal es útil para discriminar diferencias raciales y sexuales, la cual indirectamente refleja el volumen del cerebro en diferentes poblaciones. La mayoría de estos estudios se han realizado en cráneos secos con dimensiones lineales pero escasas investigaciones se han realizado en sujetos vivos. El objetivo de este trabajo fue comparar la capacidad craneal de un grupo etáreo de la tribu Korku y población no tribal de Madhya Pradesh, un estado de la India. Este estudio fue realizado en 800 voluntarios sanos, entre 20 - 25 años de edad (400 hombres y 400 mujeres) de la tribu Korku y población no tribal de Madhya Pradesh de la India, mediante el uso de las dimensiones lineales de la cabeza (fórmula de Lee Pearson ). La capacidad craneal media y DE en la población no tribal para hombres y mujeres fueron 1380,5 +/- 94,6 cc y 1188,7 +/- 91,1 cc, respectivamente. La capacidad craneal media y DE en los hobres y mujeres Korku fueron 1212,2 +/- 62,0 cc y 1047,4 +/- 72,4 cc, respectivamente. Este estudio ha mostrado una diferencia significativa (p <0,05) entre las poblaciones no tribal y la tribu Korku del mismo sexo, con los valores absolutos mayores en el grupo no tribal en comparación con el grupo de la tribu Korku.

Age effect in the morphological traits performance for sex determination in human skulls and mandibles / Efecto de la edad en el rendimiento de los rasgos morfológicos para la determinación del sexo en cráneos y mandíbulas humanas

In this study we tested the hypothesis that diagnostic performance of the morphological indicators for sexual dimorphism are reduced as they are applied in skull and mandibles of older subjects. We used 275 adult human skulls, 250 of these with mandible, all subjects with sex and age registry. Sixteen classic morphological indicators of sexual dimorphism were evaluated, this information was compared with the registry and results noted in terms of precision. The best general performance of morphological indicators of sexual dimorphism were recorded in the 31 - 40 and 61 - 70 years, age range groups. Lowest precision ws recorded in the group corresponding to subjects between 21 ­ 30 years. Our results do not support the proposed hypothesis and suggest a progressive and cumulative effect of factors that determine dimorphism expression.

En este estudio testeamos la hipótesis que el rendimiento diagnóstico de los indicadores morfológicos de dimorfismo sexual disminuía al aplicarlos en cráneos y mandíbulas de individuos de mayor edad. Utilizamos 275 cráneos humanos adultos, 250 de los cuales tenían mandíbula, todos con registro de sexo y edad. Se evaluaron 16 indicadores morfológicos clásicos de dimorfismo sexual, estos datos se contrastaron con el registro y los resultados se expresaron en términos de exactitud. El mejor rendimiento general de los indicadores morfológicos de dimorfismo sexual se encontraron en los rangos etarios de 31-40 y de 61-70 años, la menor exactitud se encontró en el grupo correspondiente a individuos de entre 21-30 años. Nuestros resultados no sustentan la hipótesis propuesta y sugieren un efecto progresivo y acumulativo de los factores que determinan la expresión de dimorfismo.

Association of mesenchymal stem cells with platelet rich plasma on the repair of critical calvarial defects in mice / Associação de células-tronco mesenquimais com plasma rico em plaquetas na reparação de defeitos críticos em calvária de camundongos

PURPOSE: To evaluate the effects of mesenchymal stem cells (MSC) from eight mice C57BL/6 gfp+ bone marrows expanded in cultures associated with platelets rich plasma (PRP) deriving from another eight mice, in the repair of critical defects in calvarial bone produced in twenty-four adult isogenic mice C57BL/6. METHODS: The animals were submitted to a cranial defect of 6.0mm in diameter and divided into two equal experimental groups. Control group did not receive treatment and the treated group received a MSC pellet containing 1.0 x 10(7) cells/mL associated with 50.0µL of plasma gel containing 1.0 x 10(9) autologous platelets within the defect. RESULTS: In the treated group was observed process of angiogenesis and bone repair better than control group. CONCLUSION: Mesenchymal stem cells derived from bone marrow of C57BL/6 gfp+ mice associated with PRP gel applied in bone critical defects produced in calvarial contributes positively to the process of bone repair.

OBJETIVO: Avaliar os efeitos da associação das células-tronco mesenquimais (MSC) oriundas da medula óssea de oito camundongos jovens C57BL/6 gfp+ e expandidas em culturas, com Plasma Rico em Plaquetas (PRP) provenientes de outros oito camundongos, na reparação de defeitos críticos confeccionados em calvária de 24 camundongos adultos C57BL/6. MÉTODOS: Os animais foram submetidos a um defeito craniano de 6,0mm de diâmetro e separados em dois grupos experimentais iguais. O grupo controle não recebeu tratamento e no grupo tratado foi administrado, no interior do defeito, pellet de MSC contendo 1,0 x 10(7) células/mL associado com 50,0µL de plasma em gel autólogo contendo 1,0 x 10(9) plaquetas. RESULTADOS: No grupo tratado verificou-se processo de angiogênese e reparação óssea superior ao grupo controle. CONCLUSÃO: A associação das células-tronco mesenquimais (MSC) derivadas da medula óssea de camundongos C57BL/6 gfp+ com gel de PRP aplicadas em defeitos ósseos críticos confeccionadas em calvária de camundongos C57BL/6 jovens, contribuiu positivamente para o processo de reparação óssea.

Metopismo: bases morfológicas, implicancias clínicas y reporte de caso / Metopism: morphologic basis clinical implications and case report

Durante la vida fetal y la infancia, los huesos planos de la bóveda craneal están separados por membranas densas de tejido conectivo que constituyen articulaciones fibrosas conocidas como suturas; las cuales tienen como objetivo durante los primeros estadios de la vida favorecer el desarrollo encefálico. Eventualmente estas suturas con el paso de los años se cierran formando una sinostosis entre los huesos del cráneo. Una de estas es la sutura frontal, que une los 2 huesos frontales en la época embrionaria y en el recién nacido. Esta sutura puede persistir en el tiempo generando el cuadro conocido como metopismo. Alteración que muestra distintas presentaciones e incidencias según sea el grupo étnico estudiado. El propósito de este artículo es mostrar las características que presenta esta condición, frecuencias, descripciones, variedades, etc., analizando distintas bases de datos, junto a la descripción de un caso. Se plantea la importancia que posee a nivel clínico a la hora de invadir quirúrgicamente esa zona, o la confusión que se puede presentar a nivel radiográfico lo cual eventualmente puede generar alguna complicación, por lo cual es de real relevancia el conocimiento de las bases morfológicas de esta condición con el fin de realizar un correcto diagnóstico y procedimiento quirúrgico si este lo amerita.

During fetal life and infancy, flat bones of the cranial vault are separated by dense connective tissue membranes, fibrous joints called sutures, which are aimed early on in life to promote brain development. Eventually these sutures close over the years to form a synostosis between the bones of the skull. One of these is the frontal suture, which joins the two frontal bones in the embryonic period and the newborn. This suture may persist over time, generating the condition known as metopism. Alteration showing different presentations and incidents depending on the ethnic group studied. The purpose of this paper is to show the features found in this condition, frequency, description, varieties, etc. This analysis was performed on different databases and the description of a case. It raises the importance that clinicians approaching the area at the time of surgery consider possible confusion at the radiographic level which can lead to subsequent complications. Therefore, real knowledge of the morphological bases of this condition is important for correct diagnosis and surgical procedure if warranted.