A novel bioactive vitroceramic presents similar biological responses as autogenous bone grafts

Bicalcium Phosphate as an Asset in Regenerative Therapy

After a loss of a tooth, alveolar bone resorption is immutable, leaving the area devoid of sufficient bone quality and mass for a successful and satisfactory implant or any other dental treatment. To treat this problem of irreversible bone loss, bone grafting is the primary solution and a well-accepted technique. The use of bone grafting procedures has increased in recent years. This review is about the various bone grafting techniques and best-situated material available currently along with their trump cards and limitations. In the thorough discussion regarding bone grafting materials and their substitutes, one alloplastic material has shown unbeaten and the most satisfactory properties than any other material, "bicalcium phosphate" (BCP). BCP is a mixture of hydroxyapatite (HA) and beta-tricalcium phosphate (B-TCP) usually obtained through sintering calcium-deficient apatite (CDA) at or above 700°C or by other methods such as hydrolysis or precipitation. The review also shows comparative studies done to understand the effect, most adequate balance, and impact of ratios of HA/B-TCP on the properties, structure, and success rate of this material. The objective of the review is to enlighten the principal characteristic of the most likely used bone graft material presently, i.e., BCP. The most impeccable characteristic of BCP is its capability to osteointegrate, which results in a superior interface. This interface depicts a dynamic process that includes physicochemical reactions, crystal-protein interactions, cell and tissue colonization, and bone remodeling. BCP has certain essential properties that could be put forth as its advantage over any other substitute. These properties include bioactivity, osteointegration, osteoinduction, osteogenesis, and biodegradation, which are mostly governed by modifying the HA/B-TCP ratio. Other applications of BCP are feasible, such as in drug administration and scaffolds for tissue engineering.

Bone Grafts in Dental Medicine: An Overview of Autografts, Allografts and Synthetic Materials

This review provides an overview of various materials used in dentistry and oral and maxillofacial surgeries to replace or repair bone defects. The choice of material depends on factors such as tissue viability, size, shape, and defect volume. While small bone defects can regenerate naturally, extensive defects or loss or pathological fractures require surgical intervention and the use of substitute bones. Autologous bone, taken from the patient's own body, is the gold standard for bone grafting but has drawbacks such as uncertain prognosis, surgery at the donor site, and limited availability. Other alternatives for medium and small-sized defects include allografts (from human donors), xenografts (from animals), and synthetic materials with osteoconductive properties. Allografts are carefully selected and processed human bone materials, while xenografts are derived from animals and possess similar chemical composition to human bone. Synthetic materials such as ceramics and bioactive glasses are used for small defects but may lack osteoinductivity and moldability. Calcium-phosphate-based ceramics, particularly hydroxyapatite, are extensively studied and commonly used due to their compositional similarity to natural bone. Additional components, such as growth factors, autogenous bone, and therapeutic elements, can be incorporated into synthetic or xenogeneic scaffolds to enhance their osteogenic properties. This review aims to provide a comprehensive analysis of grafting materials in dentistry, discussing their properties, advantages, and disadvantages. It also highlights the challenges of analyzing in vivo and clinical studies to select the most suitable option for specific situations.

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.

Tetracalcium phosphate and biphasic tetracalcium phosphate/tricalcium phosphate powders' effects evaluation on human osteoblasts

BACKGROUND

Calcium ions levels in bone niches have been demonstrated to severely influence new bone formation. Osteoinductive scaffolds containing calcium have been largely studied to control the release of calcium in bone regeneration and tissue engineering purpose. The aim of the present study was, firstly, to synthesize two different resorbable calcium phosphate-based powders, thought to be reservoirs of calcium ions, and secondary, to investigate their effects on human osteoblasts, in order to develop a suitable titanium coating material.

METHODS

Tetracalcium phosphate (A450) and biphasic tetracalcium phosphatae/tricalcium phosphate (A850) powders were prepared with an innovative method. The presence of calcium phosphate structures was chemically confirmed with XRD. Furthermore, powders macroscopic aspect was observed with a stereomicroscope. For in-vitro experiments, human osteoblastic cells were cultured in the presence of A450 and A850, and assayed for viability and metabolic activity through Crystal Violet and MTT, respectively.

RESULTS

Our synthesis led to the formation of calcium phosphates in both samples, even though A850 presented a higher level of crystallinity and a more powdery aspects than A450. Both the samples enhanced the viability of cultured cells, inhibiting cell metabolic activity in the case of A850, which furthermore showed to be internalized by cells.

CONCLUSIONS

We developed two different kind of calcium phosphate-based powders and we tested their effect on human osteoblasts, underlying the possibility of use calcium phosphate-based coatings to enhance cell response on implantable materials.

Inflammatory response and macrophage polarization using different physicochemical biomaterials for oral and maxillofacial reconstruction

Knowledge about the action of immune system in the recognition of biomaterials has been extremely helpful when it comes about understanding host response and biomaterials' fate in human body. This study aimed to investigate inflammatory response and macrophage polarization during bone healing process of rat's calvaria critical defects using different bone materials in order to evaluate their influence on bone repair and on the quality of the newly formed bone tissue. Eighty male albinus Wistar rats underwent surgical procedure for the confectioning of a 5-mm diameter bone defect in their right parietal bone, and divided in four groups (n = 20 each), according the biomaterial: AG - Control, particulate intramembranous autogenous bone graft, HA/TCP - particulate biphasic calcium phosphate with HA/TCP (60/40), DBB - particulate deproteinized bovine bone, VC - particulate bioactive vitroceramic. After 3, 7, 21, and 45 days, the specimens were removed and prepared for microcomputed tomography (microCT), light and polarized microscopy, immunohistochemical analysis, and histomorphometry. No significant differences were detected considering percentage of leukocytes among the groups and periods, as well as in relation to immunolabeling for inflammatory (M1) and reparative (M2) macrophages. However, immunolabeling for bone marker indicated a delayed osteoblast differentiation in VC group, resulting in a decrease in mineralized bone matrix parameters in this group, revealed by microCT. In addition, AG and HA/TCP presented a satisfactory bone collagenous content. Despite the distinct origins and physicochemical properties of the tested biomaterials, they presented similar immune-inflammatory responses in the present experimental model, influencing bone-related proteins and bone quality, which must be considered according to their use.

Influence of the incorporation of marine spongin into a Biosilicate®: an in vitro study

The combination of different biomaterials can be a promising intervention for the composites manufacture, mainly by adding functional and structural characteristics of each material and guarantee the advantages of the use of these composites. In this context, the aim of this study was to develop and evaluated the influence of the incorporation of marine spongin (SPG) into Biosilicate® (BS) in different proportions be used during bone repair. For this purpose, it was to develop and investigate different BS/SPG formulations for physico-chemical and morphological characteristics by pH, loss mass, Fourier transform infrared spectrometer (FTIR) and scanning electron microscope (SEM) analysis. Additionally, the influence of these composites on cell viability, proliferation, and alkaline phosphatase (ALP) activity were investigated. The results revealed that the pH values of all BS groups (with or without SPG) increased over time. A significant mass loss was observed in all composites, mainly with higher SPG percentages. Additionaly, SEM micrographies demonstrated fibers of SPG into BS and material degradation over time. Moreover, FTIR spectral analysis revealed characteristic peaks of PMMA, BS, and SPG in BS/SPG composites. BS/SPG groups demonstrated a positive effect for fibroblast proliferation after 3 and 7 days of culture. Additionally, BS and BS/SPG formulations (at 10% and 20% of SPG) presented similar values of osteoblasts viability and proliferation after 7 days of culture. Furthermore, ALP activity demonstrated no significant difference between BS and BS/SPG scaffolds, at any composition. Based on the present in vitro results, it can be concluded that the incorporation of SPG into BS was possible and produced an improvement in the physical-chemical characteristics and in the biological performance of the graft especially the formulation with 80/20 and 90/10. Future research should focus on in vivo evaluations of this novel composite.

Incorporation of collagen and PLGA in bioactive glass: in vivo biological evaluation

Bioactive glasses (BG) are known for their unique ability to bond to bone tissue. However, in critical situations, even the osteogenic properties of BG may be not sufficient to produce bone consolidation. The use of composite materials may constitute an optimized therapeutical intervention for bone stimulation. The aim of this study was to characterize BG/collagen/poly (d,l-lactic-co-glycolic) acid (BG/COL/PLGA) composites, in vitro biocompatibility and in vivo biological properties. MC3T3-E1 cells were evaluated by cell proliferation, ALP activity, cell adhesion and morphology. Qualitative histology and immunohistochemistry were performed in a calvarial bone defect model in rats. The in vitro study demonstrated, after 3 and 6 days of culture, a significant increase of proliferation was observed for BG/PLGA compared to BG/COL and BG/COL/PLGA. BG/COL/PLGA presented a higher value for ALP activity after 3 days of culture compared to BG/PLGA. For in vivo analysis, 6 weeks post-surgery, BG/PLGA showed a more mature neoformed bone tissue. As a conclusion, the in vitro and in vivo studies pointed out that BG/PLGA samples improved biological properties in calvarial bone defects, highlighting the potential of BG/PLGA composites to be used as a bone graft for bone regeneration applications.

A cleft lip and palate gene, Irf6, is involved in osteoblast differentiation of craniofacial bone

BACKGROUND

Interferon regulatory factor 6 (IRF6) plays a critical role in embryonic tissue development, including differentiation of epithelial cells. Besides orofacial clefting due to haploinsufficiency of IRF6, recent human genetic studies indicated that mutations in IRF6 are linked to small mandible and digit abnormalities. The function of IRF6 has been well studied in oral epithelium; however, its role in craniofacial skeletal formation remains unknown. In this study, we investigated the role of Irf6 in craniofacial bone development using comparative analyses between wild-type (WT) and Irf6-null littermate mice.

RESULTS

Immunostaining revealed the expression of IRF6 in hypertrophic chondrocytes, osteocytes, and bone matrix of craniofacial tissues. Histological analysis of Irf6-null mice showed a remarkable reduction in the number of lacunae, embedded osteocytes in matrices, and a reduction in mineralization during bone formation. These abnormalities may explain the decreased craniofacial bone density detected by micro-CT, loss of incisors, and mandibular bone abnormality of Irf6-null mice. To validate the autonomous role of IRF6 in bone, extracted primary osteoblasts from calvarial bone of WT and Irf6-null pups showed no effect on osteoblastic viability and proliferation. However, a reduction in mineralization was detected in Irf6-null cells.

CONCLUSIONS

Altogether, these findings suggest an autonomous role of Irf6 in regulating bone differentiation and mineralization. Developmental Dynamics 248:221-232, 2019. © 2019 Wiley Periodicals, Inc.

Distinct healing pattern of maxillary sinus augmentation using the vitroceramic Biosilicate®: Study in rabbits

OBJECTIVES

To follow healing process of augmented maxillary sinus in rabbits analyzing the histological pattern of bone tissue formation, along with the osteogenic activity and vascularization using a bioactive vitroceramic in comparison to deproteinized bovine bone associated or not with autogenous bone graft.

DESIGN

Forty five male adult New Zealand rabbits, 5 months of age, mean weight of 4 Kg, underwent bilateral sinus augmentation surgeries to be divided in five groups: G - (Control) particulate autogenous bone graft (AG), BO - deproteinized bovine bone, BO+G - deproteinized bovine bone + AG, BSi -vitroceramic, and BSi + G - vitroceramic +AG. After 15, 45 and 90 days, all animals were euthanized for specimen's removal to be analyzed under light microscopy, histomorphometry, and immunohistochemistry for Runx2 and VEGF labeling.

RESULTS

G, BO and BO+G groups healed uneventfully, allowing the formation of mature remodeling bone at day 90, regarding the association of AG with the biomaterial. On the other hand, BSi and BSi + G groups showed an important cellular reaction and granulation/fibrous tissue formation from the first to the last period of observation. Runx-2 and VEGF immunolabeling were coherent with this result. However, histomorphometry did not reveal significant differences considering new bone formation.

CONCLUSIONS

Reconstructed maxillary sinuses using Biosilicate® permitted satisfactory new bone formation in comparison to the deproteinized bovine bone and AG. However, the presence of granulation/fibrous tissue and inflammatory cells associated to the degrading biomaterial indicate that further studies should be careful performed considering the immunological aspect of this new biomaterial.

Scaffolds of bioactive glass-ceramic (Biosilicate®) and bone healing: A biological evaluation in an experimental model of tibial bone defect in rats

This study aimed to investigate the in vivo tissue response of the Biosilicate® scaffolds in a model of tibial bone defect. Sixty male Wistar rats were distributed into bone defect control group (CG) and Biosilicate® scaffold group (BG).  Animals were euthanized 15, 30 and 45 days post-surgery. Stereomicroscopy, scanning electron microscopy, histopathological, immunohistochemistry and biomechanical analysis were used. Scaffolds had a total porosity of 44%, macroporosity of 15% with pore diameter of 230 μm. Higher amount of newly formed bone was observed on days 30 and 45 in BG. Immunohistochemistry analysis showed that the COX-2 expression was significantly higher on days 15 and 30 in BG compared with the CG. RUNX-2 immunoexpression was significantly higher in BG on days 15 and 45. No statistically significant difference was observed in RANKL immunoexpression in all experimental groups. BMP-9 immunoexpression was significantly upregulated in the BG on day 45. Biomechanical analysis showed a decrease in the biomechanical properties of the bone callus on days 30 and 45. The implantation of the Biosilicate® scaffolds was effective in stimulating newly bone formation and produced an increased immunoexpression of markers related to the bone repair.

Bioactive glass-ceramic bone repair associated or not with autogenous bone: a study of organic bone matrix organization in a rabbit critical-sized calvarial model

OBJECTIVE

The aim of the study was to analyze bone matrix (BMX) organization after bone grafting and repair using a new bioactive glass-ceramic (Biosilicate^®) associated or not with particulate autogenous bone graft.

MATERIAL AND METHODS

Thirty rabbits underwent surgical bilateral parietal defects and divided into groups according to the materials used: (C) control-blood clot, (BG) particulate autogenous bone, (BS) bioactive glass-ceramic, and BG + BS. After 7, 14, and 30 days post-surgery, a fragment of each specimen was fixed in - 80 °C liquid nitrogen for zymographic evaluation, while the remaining was fixed in 10% formalin for histological birefringence analysis.

RESULTS

The results of this study demonstrated that matrix organization in experimental groups was significantly improved compared to C considering collagenous organization. Zymographic analysis revealed pro-MMP-2, pro-MMP-9, and active (a)-MMP-2 in all groups, showing gradual decrease of total gelatinolytic activity during the periods. At day 7, BG presented more prominent gelatinolytic activity for pro-MMP-2 and 9 and a-MMP-2, when compared to the other groups. In addition, at day 7, a 53% activation ratio (active form/[active form + latent form]) was evident in C group, 33% in BS group, and 31% in BG group.

CONCLUSION

In general, BS allowed the production of a BMX similar to BG, with organized collagen deposition and MMP-2 and MMP-9 disponibility, permitting satisfactory bone remodeling at the late period.

CLINICAL RELEVANCE

The evaluation of new bone substitute, with favorable biological properties, opens the possibility for its use as a viable and efficient alternative to autologous bone graft.

Experimental maxillary sinus augmentation using a highly bioactive glass ceramic

Physicochemical characteristics of a biomaterial directly influence its biological behavior and fate. However, anatomical and physiological particularities of the recipient site also seem to contribute with this process. The present study aimed to evaluate bone healing of maxillary sinus augmentation using a novel bioactive glass ceramic in comparison with a bovine hydroxyapatite. Bilateral sinus augmentation was performed in adult male rabbits, divided into 4 groups according to the biomaterial used: BO-particulate bovine HA Bio-Oss(®) (BO), BO+G-particulate bovine HA + particulate autogenous bone graft (G), BS-particulate glass ceramic (180-212 μm) Biosilicate(®) (BS), and BS+G-particulate glass ceramic + G. After 45 and 90 days, animals were euthanized and the specimens prepared to be analyzed under light and polarized microscopy, immunohistochemistry, scanning electron microscopy (SEM), and micro-computed tomography (μCT). Results revealed different degradation pattern between both biomaterials, despite the association with bone graft. BS caused a more intense chronic inflammation with foreign body reaction, which led to a difficulty in bone formation. Besides this evidence, SEM and μCT confirmed direct contact between newly formed bone and biomaterial, along with osteopontin and osteocalcin immunolabeling. Bone matrix mineralization was late in BS group but became similar to BO at day 90. These results clearly indicate that further studies about Biosilicate(®) are necessary to identify the factors that resulted in an unfavorable healing response when used in maxillary sinus augmentation.

Evaluation of Crystallized Biosilicate in the Reconstruction of Calvarial Defects

INTRODUCTION

The objective of this study was to assess the bone repair process of crystallized Biosilicate in surgically created defects on rats' calvaria. This biomaterial was recently developed for odontological use.

MATERIALS AND METHODS

We used fifteen rats (rattus norvegicus albinus, Wistar), and two 5 mm surgical defects were performed on each of them; the defects were made with trephine drill on the calvarium region prior to the biomaterial placement. Groups were divided as follows: Group 1-defect filled with clot; Group 2-defect filled with crystallized Biosilicate. After 7, 14 and 28 days the animals were killed, the parts were retrieved and slides were prepared for histological studies.

RESULTS

Bone formation was satisfactory in all groups, with direct contact between biomaterial surface and bone and absence of infection signs. The 28 days periods showed better results, and statistically significant difference between Clot Group (90.2 %) and Biosilicate (58 %; p = 0.002) was seen, regarding presence of bone tissue on the surgical defects.

CONCLUSION

Our study revealed that defects filled with clot present better results on bone formation compared to crystallized Biosilicate, which is considered a biocompatible material with favorable osteoconductive properties.

Effect of a new bioactive fibrous glassy scaffold on bone repair

Researchers have investigated several therapeutic approaches to treat non-union fractures. Among these, bioactive glasses and glass ceramics have been widely used as grafts. This class of biomaterial has the ability to integrate with living bone. Nevertheless, bioglass and bioactive materials have been used mainly as powder and blocks, compromising the filling of irregular bone defects. Considering this matter, our research group has developed a new bioactive glass composition that can originate malleable fibers, which can offer a more suitable material to be used as bone graft substitutes. Thus, the aim of this study was to assess the morphological structure (via scanning electron microscope) of these fibers upon incubation in phosphate buffered saline (PBS) after 1, 7 and 14 days and, also, evaluate the in vivo tissue response to the new biomaterial using implantation in rat tibial defects. The histopathological, immunohistochemistry and biomechanical analyzes after 15, 30 and 60 days of implantation were performed to investigate the effects of the material on bone repair. The PBS incubation indicated that the fibers of the glassy scaffold degraded over time. The histological analysis revealed a progressive degradation of the material with increasing implantation time and also its substitution by granulation tissue and woven bone. Histomorphometry showed a higher amount of newly formed bone area in the control group (CG) compared to the biomaterial group (BG) 15 days post-surgery. After 30 and 60 days, CG and BG showed a similar amount of newly formed bone. The novel biomaterial enhanced the expression of RUNX-2 and RANK-L, and also improved the mechanical properties of the tibial callus at day 15 after surgery. These results indicated a promising use of the new biomaterial for bone engineering. However, further long-term studies should be carried out to provide additional information concerning the material degradation in the later stages and the bone regeneration induced by the fibrous material.

Porous bioactive scaffolds: characterization and biological performance in a model of tibial bone defect in rats

The aim of this study was to evaluate the effects of highly porous Biosilicate(®) scaffolds on bone healing in a tibial bone defect model in rats by means of histological evaluation (histopathological and immunohistochemistry analysis) of the bone callus and the systemic inflammatory response (immunoenzymatic assay). Eighty Wistar rats (12 weeks-old, weighing±300 g) were randomly divided into 2 groups (n=10 per experimental group, per time point): control group and Biosilicate® group (BG). Each group was euthanized 3, 7, 14 and 21 days post-surgery. Histological findings revealed a similar inflammatory response in both experimental groups, 3 and 7 days post-surgery. During the experimental periods (3-21 days post-surgery), it was observed that the biomaterial degradation, mainly in the periphery region, provided the development of the newly formed bone into the scaffolds. Immunohistochemistry analysis demonstrated that the Biosilicate® scaffolds stimulated cyclooxygenase-2, vascular endothelial growth factor and runt-related transcription factor 2 expression. Furthermore, in the immunoenzymatic assay, BG presented no difference in the level of tumor necrosis factor alpha in all experimental periods. Still, BG showed a higher level of interleukin 4 after 14 days post-implantation and a lower level of interleukin 10 in 21 days post-surgery. Our results demonstrated that Biosilicate® scaffolds can contribute for bone formation through a suitable architecture and by stimulating the synthesis of markers related to the bone repair.

Evaluation of the bone healing process in an experimental tibial bone defect model in ovariectomized rats

The aim of this study was to evaluate the influence of postmenopausal bone loss (induced by ovariectomy) in the process of bone healing in a tibial bone defect model in rats by means of histological evaluation of bone defects and the analysis of the expression of genes and proteins involved in bone consolidation. Twenty female Wistar rats (12 weeks old, weighing ±250 g) were randomly divided into two groups: control group (CG) and ovariectomized group (OG). Rats of OG were submitted to ovariectomy and after 8 weeks post-surgery, all animals were submitted to the tibial bone defect model. The main histological finding analysis revealed that ovariectomized animals showed a higher amount of granulation tissue and immature newly formed bone compared to CG. Furthermore, quantitative histological analysis showed that OG presented a significant decrease in the amount of newly formed bone (p = 0.0351). RT-PCR analysis showed no difference in Runx2, ALP, RANK, RANKL and Osterix gene expression 14-day post-surgery. Interestingly, immunohistochemical evaluation showed that Runx2 was down expressed (p = 0.0001) and RANKL was up expressed (p = 0.0022) in the OG. In conclusion, these data highlight that bone loss induced by ovariectomy causes an impairment in the capacity of bone to heal mainly probably because of alterations in the imbalance of osteoblasts and osteoclasts activities.

Sintered anorganic bone graft increases autocrine expression of VEGF, MMP-2 and MMP-9 during repair of critical-size bone defects

This study aimed to evaluate morphometrically the bone formation and immunohistochemically the expression of vascular endothelial growth factor (VEGF) and metalloproteinase (MMP)-2 and -9 during the healing of critical-size defects treated with sintered anorganic bone (sAB). The 8-mm diameter full-thickness trephine defects created in the parietal bones of rats were filled with sAB (test group) or blood clot (CSD-control group). At 7, 14, 21, 30, 90 and 180 days postoperatively (n = 6/period) the volume of newly formed bone and total number of immunolabeled cells (Ntm) for each protein were determined. Bone formation was smaller and faster in the CSD-control group, stabilizing at 21 days (6.74 mm(3)). The peaks of VEGF, MMP-2 and MMP-9 occurred at 7 and 14 days in fibroblasts and osteoblasts, with mean reduction of 0.80 time at 21 days, keeping constant until 180 days. In the test group, sAB provided continuous bone formation between particles throughout all periods. The peak of MMP-2 was observed at 7-14 days in connective tissue cells and for VEGF and MMP-9 at 30 days in osteoblasts and osteocytes. Ntm for VEGF, MMP-2 and MMP-9 were in average, respectively, 3.70, 2.03 and 5.98 times higher than in the control group. At 180 days, newly formed bone (22.9 mm(3)) was 3.74 times greater in relation to control. The physical and chemical properties of sAB allow increased autocrine expression of VEGF, MMP-2 and MMP-9, favoring bone formation/remodeling with very good healing of cranial defects when compared to natural repair in the CSD-control.