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Introdução: O antígeno prostático específico (PSA) é crucial para monitorar o câncer de próstata, uma das principais causas de mortalidade masculina no Brasil e EUA. A confiabilidade dos resultados de PSA fornece um diagnóstico eficiente para direcionar a terapia, avaliação de resposta ao tratamento e epidemiologia. Entretanto, há discrepâncias conhecidas nos resultados de diferentes laboratórios. A rastreabilidade metrológica surge como fator-chave para comparabilidade e precisão desses resultados, sendo um tema de pouco conhecimento na comunidade laboratorial. Objetivo: Identificar a rastreabilidade metrológica dos kits de PSA Total registrados no Brasil. Método: Foi realizada uma pesquisa na página de registros de produtos da Anvisa, onde foram analisadas a procedência e as instruções de uso dos kits disponibilizados pelos fabricantes de diagnóstico in vitro (IVD). Resultados: Os dados da Anvisa mostraram que 75,0% dos produtores de IVD utilizam o produto OMS 96/670, e 25,0% não mencionam rastreabilidade metrológica. Predominam produtos estrangeiros (87,5%), com apenas dois kits nacionais registrados, que não informam sobre rastreabilidade. Conclusões: O mercado brasileiro de kits diagnóstico para PSA Total (excetuando-se testes rápidos e PSA livre) é predominantemente de produtos estrangeiros que utilizam o material de referência OMS 96/670. A ausência de informações sobre rastreabilidade em um número significativa de produtos IVD evidencia a necessidade de ações regulatórias e educacionais para promover a conscientização e a conformidade com os princípios de rastreabilidade metrológica, melhorando, assim, a qualidade e a confiabilidade dos testes laboratoriais para a proteção da saúde pública.

The strategies used to associate peptide arginylglycylaspartic acid (RGD) with calcium phosphate grafts to enhance cell–biomaterial interactions have been controversial in the literature. Several works have demonstrated that RGD-functionalized hydroxyapatite (HA) surfaces improve cell adhesion, whereas others claim that RGD-loaded HA has an inhibitory effect when serum is present in the biological medium. To investigate such contradictory results, we associated RGD with the HA surface using physical adsorption and chemical bonding methods and evaluated the cell adhesion and spreading in pre-osteoblasts culture with and without fetal bovine serum (FBS). The effect of functionalization methods on the physicochemical characteristics of both surfaces was analyzed using multiscale techniques. Adsorption assays of serum allowed us to estimate the impact of the association method on the HA surface’s reactivity. Physically adsorbed RGD did not increase the number of adhered cells due to the weak interactions between the peptide and the surface. Although chemical binding stabilizes RGD on the HA, the functionalization procedure covered the surface with molecules such as (3-aminopropyl)triethoxysilane (APTEs) and carbodiimide, changing the surface’s chemical activity. Serum protein adsorption decreased by 90%, revealing a significant reduction in the surface interactions with molecules of the biological medium. The present study’s findings showed that the RGD’s physical association with HA did not improve cell adhesion and that this phenomenon is highly dependent on the presence of serum proteins.

O debate quanto às melhores práticas da regulação das nanotecnologias precisa ser aprofundado, pois ainda representa um desafio para a sociedade brasileira, autoridades políticas e regulatórias. Nos últimos anos, muito se fala na regulação das nanotecnologias, porém, como tecnologia disruptiva, pela complexidade, limitações na validação de metodologias de análise e escassas referências sobre nanopartículas e nanomateriais, ainda persistem expressivas assimetrias e dificuldades de compreensão sobre as melhores práticas regulatórias. Atualmente, pelas ainda limitadas evidências técnicas e científicas validadas, utilizam-se os modelos de regulação denominados de comando e controle e o princípio da precaução como meio de evitar o perigo concreto/abstrato, mas cuja ocorrência seja verossímil. Como alternativa ao atual modelo regulatório, no presente texto, discorre-se sobre o modelo regulatório, tratado como a melhor prática regulatória global e que se vale da ciência regulatória e da regulação baseada em evidências. Globalmente cresce a aceitação do uso de evidências técnicas e científicas validadas para auxiliar autoridades políticas e regulatórias na elaboração de diretrizes e normas regulatórias que consigam proteger os interesses públicos e maximizar os benefícios econômicos e sociais das novas tecnologias. Para além disso, evidências permitem antecipar possíveis riscos e permitem abordagens proativas para a regulação das nanotecnologias. E ao considerar essa perspectiva, é importante enfatizar que a implementação de um modelo de regulação baseada em evidências requer maturidade política, científica, técnica e regulatória, para que os benefícios sejam aproveitados de maneira a prover prosperidade, segurança e sustentabilidade pelo uso de tecnologias disruptivas.

Introdução: Há décadas, a necessidade, o número e o potencial preditivo do uso de animais para fins de pesquisa, produção e controle da qualidade de diversos produtos vêm sendo questionados. Objetivo: Mapear os testes in vivo utilizados nos laboratórios públicos oficiais (LPO), verificando a aplicação ou não de métodos alternativos. Método: Os LPO foram identificados e convidados a responder um questionário de triagem para mapear os métodos alternativos utilizados por eles seguido de uma entrevista para avaliar o interesse em desenvolver um novo método alternativo, a aplicação do princípio dos 3Rs e a percepção dos fabricantes em relação à tendência da substituição por métodos alternativos. Resultados: Os LPO brasileiros reportaram dificuldades para a implementação de alternativas in vitro, entre elas a necessidade de adequação de infraestrutura, insuficiência de pessoal e falta de capacitação dos quadros técnicos. Alguns respondentes alegam a necessidade de sistematização dos trâmites burocráticos e regulatórios aplicáveis ao conceito dos 3Rs no campo de imunobiológicos. Todos os respondentes apresentaram interesse na implementação de alternativas in vitro, apontando vantagens como: redução de tempo e custo das análises, maior precisão de resultados, minimização de dificuldades inerentes aos testes in vivo e à manipulação de animais. Conclusões: Promover um cenário – sob o ponto de vista político, técnico e regulatório – mais propício para validação e implementação de métodos alternativos no Brasil contribuirá para a redução de custo e o tempo na liberação de lotes de produtos imunobiológicos. Há espaço para a redução do uso de animais em alguns testes in vivo utilizados na LPO, porém, há necessidade de investimento em infraestrutura e pessoal qualificado em testes alternativos.

Bone critical-size defects and non-union fractures have no intrinsic capacity for self-healing. In this context, the emergence of bone engineering has allowed the development of functional alternatives. The aim of this study was to evaluate the capacity of ASC spheroids in bone regeneration using a synergic strategy with 3D-printed scaffolds made from poly (lactic acid) (PLA) and nanostructured hydroxyapatite doped with carbonate ions (CHA) in a rat model of cranial critical-size defect. In summary, a set of results suggests that ASC spheroidal constructs promoted bone regeneration. In vitro results showed that ASC spheroids were able to spread and interact with the 3D-printed scaffold, synthesizing crucial growth factors and cytokines for bone regeneration, such as VEGF. Histological results after 3 and 6 months of implantation showed the formation of new bone tissue in the PLA/CHA scaffolds that were seeded with ASC spheroids. In conclusion, the presence of ASC spheroids in the PLA/CHA 3D-printed scaffolds seems to successfully promote bone formation, which can be crucial for a significant clinical improvement in critical bone defect regeneration.

Bone tissue engineering seeks biomaterials that enable cell migration, angiogenesis, matrix deposition, and tissue regeneration. Blood concentrates like platelet-rich fibrin (L-PRF) offer a cost-effective source of cells and growth factors to enhance healing. The present study aimed to evaluate heated serum albumin with liquid PRF (Alb-PRF) and L-PRF clinically and biochemically after placement in dental sockets following mandibular third molar extraction. In a controlled, split-mouth study involving 10 volunteers, 20 extracted molars were treated with either Alb-PRF or L-PRF. Post-extraction, pain, trismus, infection presence, and swelling were measured. The concentrations of different analytes in the surgical sites were also examined. The data were statistically analyzed, with significance defined at p < 0.05 (t-test). No significant difference was noted between the groups for pain and trismus, but Alb-PRF showed a significant reduction in swelling on day seven. The Alb-PRF group showed lower levels of pro-inflammatory cytokines (GM-CSF, IL-1b, IL-6, IFNy, IL-8, IL-15, RANTES, and MIP-1a) after seven days, with only higher expressions of MIP-1b, IL-1b, and MCP-1 found in the L-PRF group. Differences were observed in the release of analytes between L-PRF and Alb-PRF, with Alb-PRF significantly reducing edema after seven days. Alb-PRF reduced edema, while L-PRF increased inflammatory cytokines. When compared to L-PRF, Alb-PRF reduced edema and the release of inflammatory cytokines, suggesting promising effects in socket healing while underscoring the role of growth factors and cytokines in potential applications of blood concentrates.

Abstract Background Temporomandibular disorders (TMD) are a group of painful and debilitating disorders, involving the masticatory muscles and/or the temporomandibular joint (TMJ). Chronic TMD pain can be associated with genetic changes in the key muscle development genes. Objective To evaluate the association between polymorphisms in the PAX7 (paired box 7) gene and masticatory myalgia in patients with temporomandibular disorders (TMD). Materials and methods This is a case-control study. Patients with TMD were divided into two groups: (a) presence of muscular TMD (n = 122) and (b) absence of muscular TMD (n = 49). Genomic DNA was obtained from saliva samples from all participants to allow for genotyping single nucleotide polymorphisms in PAX7 (rs766325 and rs6659735). Over-representation of alleles was tested using chi-square or Fisher’s exact tests. Values of p

Although several studies assess the biological effects of micro and titanium dioxide nanoparticles (TiO2 NPs), the literature shows controversial results regarding their effect on bone cell behavior. Studies on the effects of nanoparticles on mammalian cells on two-dimensional (2D) cell cultures display several disadvantages, such as changes in cell morphology, function, and metabolism and fewer cell–cell contacts. This highlights the need to explore the effects of TiO2 NPs in more complex 3D environments, to better mimic the bone microenvironment. This study aims to compare the differentiation and mineralized matrix production of human osteoblasts SAOS-2 in a monolayer or 3D models after exposure to different concentrations of TiO2 NPs. Nanoparticles were characterized, and their internalization and effects on the SAOS-2 monolayer and 3D spheroid cells were evaluated with morphological analysis. The mineralization of human osteoblasts upon exposure to TiO2 NPs was evaluated by alizarin red staining, demonstrating a dose-dependent increase in mineralized matrix in human primary osteoblasts and SAOS-2 both in the monolayer and 3D models. Furthermore, our results reveal that, after high exposure to TiO2 NPs, the dose-dependent increase in the bone mineralized matrix in the 3D cells model is higher than in the 2D culture, showing a promising model to test the effect on bone osteointegration.

Background and objectives: Calcium phosphates have been widely used as bone substitutes, but their properties are limited to osteoconduction. The association of calcium phosphates with osteoinductive bioactive molecules has been used as a strategy in regenerative medicine. Melatonin has been studied due to its cell protection and antioxidant functions, reducing osteoclastic activity and stimulating newly formed bone. This study aimed to evaluate the effect of topical application of melatonin associated with nanostructured carbonated hydroxyapatite microspheres in the alveolar bone repair of Wistar rats through histological and histomorphometric analysis. Materials and Methods: Thirty female Wistar rats (300 g) were used, divided randomly into three experimental groups (n = 10), G1: nanostructured carbonated hydroxyapatite microspheres associated with melatonin gel (CHA-M); G2: nanostructured carbonated hydroxyapatite (CHA); G3: blood clot (without alveolar filling). The animals were euthanized after 7 and 42 days of the postoperative period and processed for histological and histomorphometric evaluation. Kruskal–Wallis and Dunn’s post-test were applied to investigate statistical differences between the groups at the same time point for new bone and connective tissue variables. Mann–Whitney was used to assess statistical differences between different time points and in the biomaterial variable. Results: Results showed a greater volume of residual biomaterial in the CHA-M than the CHA group (p = 0.007), and there were no significant differences in terms of newly formed bone and connective tissue between CHA and CHA-M after 42 days. Conclusions: This study concluded that both biomaterials improved alveolar bone repair from 7 to 42 days after surgery, and the association of CHA with melatonin gel reduced the biomaterial’s biodegradation at the implanted site but did not improve the alveolar bone repair.

Abstract Background The blood brain barrier (BBB) is the bottleneck of brain-targeted drug development. Due to their physico-chemical properties, nanoparticles (NP) can cross the BBB and accumulate in different areas of the central nervous system (CNS), thus are potential tools to carry drugs and treat brain disorders. In vitro systems and animal models have demonstrated that some NP types promote neurotoxic effects such as neuroinflammation and neurodegeneration in the CNS. Thus, risk assessment of the NP is required, but current 2D cell cultures fail to mimic complex in vivo cellular interactions, while animal models do not necessarily reflect human effects due to physiological and species differences. Results We evaluated the suitability of in vitro models that mimic the human CNS physiology, studying the effects of metallic gold NP (AuNP) functionalized with sodium citrate (Au-SC), or polyethylene glycol (Au-PEG), and polymeric polylactic acid NP (PLA-NP). Two different 3D neural models were used (i) human dopaminergic neurons differentiated from the LUHMES cell line (3D LUHMES) and (ii) human iPSC-derived brain spheroids (BrainSpheres). We evaluated NP uptake, mitochondrial membrane potential, viability, morphology, secretion of cytokines, chemokines and growth factors, and expression of genes related to ROS regulation after 24 and 72 h exposures. NP were efficiently taken up by spheroids, especially when PEGylated and in presence of glia. AuNP, especially PEGylated AuNP, effected mitochondria and anti-oxidative defense. PLA-NP were slightly cytotoxic to 3D LUHMES with no effects to BrainSpheres. Conclusions 3D brain models, both monocellular and multicellular are useful in studying NP neurotoxicity and can help identify how specific cell types of CNS are affected by NP.

Abstract Cone-beam computed tomography (CBCT) is an essential imaging method that increases the accuracy of diagnoses, planning and follow-up of endodontic complex cases. Image postprocessing and subsequent visualization relies on software for three-dimensional navigation, and application of indexation tools to provide clinically useful information according to a set of volumetric data. Image postprocessing has a crucial impact on diagnostic quality and various techniques have been employed on computed tomography (CT) and magnetic resonance imaging (MRI) data sets. These include: multiplanar reformations (MPR), maximum intensity projection (MIP) and volume rendering (VR). A recent advance in 3D data visualization is the new cinematic rendering reconstruction method, a technique that generates photorealistic 3D images from conventional CT and MRI data. This review discusses the importance of CBCT cinematic rendering for clinical decision-making, teaching, and research in Endodontics, and a presents series of cases that illustrate the diagnostic value of 3D cinematic rendering in clinical care.

Titanium dioxide nanoparticles (TiO2 NPs) are regularly used in sunscreens because of their photoprotective capacity. The advantage of using TiO2 on the nanometer scale is due to its transparency and better UV blocking efficiency. Due to the greater surface area/volume ratio, NPs become more (bio)-reactive giving rise to concerns about their potential toxicity. To evaluate the irritation and corrosion of cosmetics, 3D skin models have been used as an alternative method to animal experimentation. However, it is not known if this model is appropriate to study skin irritation, corrosion and phototoxicity of nanomaterials such as TiO2 NPs. This systematic review (SR) proposed the following question: Can the toxicity of TiO2 nanoparticles be evaluated in a 3D skin model? This SR was conducted according to the Preliminary Report on Systematic Review and Meta-Analysis (PRISMA). The protocol was registered in CAMARADES and the ToxRTool evaluation was performed in order to increase the quality and transparency of this search. In this SR, 7 articles were selected, and it was concluded that the 3D skin model has shown to be promising to evaluate the toxicity of TiO2 NPs. However, most studies have used biological assays that have already been described as interfering with these NPs, demonstrating that misinterpretations can be obtained. This review will focus in the possible efforts that should be done in order to avoid interference of NPs with biological assays applied in 3D in vitro culture.

Craniofacial development comprises a complex process in humans in which failures or disturbances frequently lead to congenital anomalies. Cleft lip with/without palate (CL/P) is a common congenital anomaly that occurs due to variations in craniofacial development genes, and may occur as part of a syndrome, or more commonly in isolated forms (non-syndromic). The etiology of CL/P is multifactorial with genes, environmental factors, and their potential interactions contributing to the condition. Rehabilitation of CL/P patients requires a multidisciplinary team to perform the multiple surgical, dental, and psychological interventions required throughout the patient’s life. Despite progress, lip/palatal reconstruction is still a major treatment challenge. Genetic mutations and polymorphisms in several genes, including extracellular matrix (ECM) genes, soluble factors, and enzymes responsible for ECM remodeling (e.g., metalloproteinases), have been suggested to play a role in the etiology of CL/P; hence, these may be considered likely targets for the development of new preventive and/or therapeutic strategies. In this context, investigations are being conducted on new therapeutic approaches based on tissue bioengineering, associating stem cells with biomaterials, signaling molecules, and innovative technologies. In this review, we discuss the role of genes involved in ECM composition and remodeling during secondary palate formation and pathogenesis and genetic etiology of CL/P. We also discuss potential therapeutic approaches using bioactive molecules and principles of tissue bioengineering for state-of-the-art CL/P repair and palatal reconstruction.

ABSTRACT OBJECTIVE: To define the anthropometric profile of the knee in a Brazilian population with gonarthrosis using intraoperative measurements; and to evaluate the compatibility of three implants available for total knee arthroplasty. METHODS: Morphometric data were collected prospectively from 117 subjects with gonarthrosis. Six dimensions in the distal femur and two in the proximal tibia were documented in 118 knees while performing total arthroplasty. These data were compared with the dimensions of three implants available for total knee arthroplasty. RESULTS: The statistical analysis showed that more than a quarter of the patients presented an unsatisfactory relationship between the knee and prosthesis. CONCLUSION: The implants evaluated need to be adjusted to better fit Brazilian patients.

O objetivo do presente trabalho foi comparar e analisar os requisitos necessários para registro e as ações de tecnovigilância para implantes dentários nos EUA, na União Europeia e no Brasil. Após análise da literatura e das principais normas em vigor, observou-se a preocupação com o controle de riscos e a prevenção de falhas no uso dos implantes dentários. Nos EUA, o sistema de registro e tecnovigilância é centralizado e se verificam problemas de subnotificação e falhas na análise dos relatórios de notificação, bem como um intervalo de tempo longo entre a identificação dos problemas e a ação devido à extensão do processo administrativo. Na União Europeia, os poucos estudos identificados sugerem que o sistema regulatório oferece riscos aos pacientes devido à ausência de transparência entre os Órgãos Notificadores e à dificuldade em se articular a tecnovigilância entre os países. No Brasil, a tecnovigilância é centralizada, porém ainda é incipiente. O envelhecimento da população promove forte demanda por reabilitação oral dos pacientes, sobretudo os carentes, prevista no programa Brasil Sorridente. A demanda pelo serviço oferece uma oportunidade de expansão do mercado, mas detecta-se risco de entrada de produtos de baixa qualidade. Neste contexto, o aprimoramento das atividades de tecnovigilância de implantes dentários é necessário. -------------------------------------------------------------------------------------------- This study compared and analyzed, after reviewing the literature and the main legal regulations, the requirements for registration and the post-marketing surveillance activities of dental implants in the USA, the European Union and in Brazil. The legal regulations studied showed a concern for risk control and for prevention of failures in the use of dental implants. In the US, the system is centralized, which produces underreporting problems and flaws in the analysis of reporting, as well as a long time between problems identification and the action (due to the extension of the administrative process). In the European Union the few identified studies suggested that the regulatory system provides risks to patients related to the lack of transparency among notifying organs and to the difficulty in articulating the post-marketing surveillance among countries. In Brazil, the post-marketing surveillance is centralized, and is still in its infancy, having the “sentinel” hospitals and “Notivisa” as its main initiatives. Population ageing promotes strong demand for patients’ oral rehabilitation, especially the needy included in the “Smiling Brazil” program. The service demand may offer a market expansion opportunity, but it also poses a risk of low-quality products entry. In this context, the improvement of post-market surveillance activities of dental implants becomes a priority.

Objective The goal of this review was to determine whether calcium silicate (wollastonite) as a bone graft material is a viable alternative to autogenous bone or whether the evidence base for its use is weak. Methods In this systematic review, electronic databases (MEDLINE/PubMed and BVS) were searched for relevant articles in indexed journals. Articles published in a 10-year period were identified (n = 48). After initial selection, 17 articles were assessed for eligibility; subsequently, seven articles were excluded and 10 articles were included. Results Among the studies included, 20% emphasized the importance of randomization, which adds reliability to the study, minimizing the risk of bias. High variability was observed in the material used, such as additives, amounts, dosage, and chemical alterations, rendering direct comparison among these studies impossible. The experimental periods varied considerably; one of the studies did not include statistical analysis, weakening the evaluation. Nonetheless, the true potential of wollastonite as a graft material conducive to new bone formation was reported in all studies. Conclusion The results support the use of wollastonite as a bone graft material. The initial research question was answered despite the significant variability observed among these preclinical studies, which hindered the precision of this analysis.

Abstract Objectives To evaluate the association between hypoxia during embryo development and oral clefts in an animal model, and to evaluate the association between polymorphisms in the HIF-1A gene with oral clefts in human families. Material and Methods The study with the animal model used zebrafish embryos at 8 hours post-fertilization submitted to 30% and 50% hypoxia for 24 hours. At 5 days post-fertilization, the larvae were fixed. The cartilage structures were stained to evaluate craniofacial phenotypes. The family-based association study included 148 Brazilian nuclear families with oral clefts. The association between the genetic polymorphisms rs2301113 and rs2057482 in HIF-1A with oral clefts was tested. We used real time PCR genotyping approach. ANOVA with Tukey's post-test was used to compare means. The transmission/disequilibrium test was used to analyze the distortion of the inheritance of alleles from parents to their affected offspring. Results For the hypoxic animal model, the anterior portion of the ethmoid plate presented a gap in the anterior edge, forming a cleft. The hypoxia level was associated with the severity of the phenotype (p0.05). Conclusion Hypoxia is involved in the oral cleft etiology, however, polymorphisms in HIF-1A are not associated with oral clefts in humans.

A expectativa de vida média dos seres humanos vem aumentando progressivamente. Contudo, é fato inegável que, além de viver mais, se quer viver com qualidade de vida. Neste cenário, as perspectivas do uso de células como ferramentas tornaram-se um foco importante e profícuo da pesquisa mundial.

ABSTRACT Objective: This study aimed to evaluate bone repair in rat dental sockets after implanting nanostructured carbonated hydroxyapatite/sodium alginate (CHA) and nanostructured carbonated hydroxyapatite/sodium alginate containing 5% strontium microspheres (SrCHA) as bone substitute materials. Methods: Twenty male Wistar rats were randomly divided into two experimental groups: CHA and SrCHA (n=5/period/group). After one and 6 weeks of extraction of the right maxillary central incisor and biomaterial implantation, 5 μm bone blocks were obtained for histomorphometric evaluation. The parameters evaluated were remaining biomaterial, loose connective tissue and newly formed bone in a standard area. Statistical analysis was performed by Mann-Withney and and Wilcoxon tests at 95% level of significance. Results: The histomorphometric results showed that the microspheres showed similar fragmentation and bio-absorbation (p>0.05). We observed the formation of new bones in both groups during the same experimental periods; however, the new bone formation differed significantly between the weeks 1 and 6 (p=0.0039) in both groups. Conclusion: The CHA and SrCHA biomaterials were biocompatible, osteoconductive and bioabsorbable, indicating their great potential for clinical use as bone substitutes.

ABSTRACT Objective The aim of this study was to investigate the in vitro and in vivo biological responses to nanostructured carbonated hydroxyapatite/calcium alginate (CHA) microspheres used for alveolar bone repair, compared to sintered hydroxyapatite (HA). Material and Methods The maxillary central incisors of 45 Wistar rats were extracted, and the dental sockets were filled with HA, CHA, and blood clot (control group) (n=5/period/group). After 7, 21 and 42 days, the samples of bone with the biomaterials were obtained for histological and histomorphometric analysis, and the plasma levels of RANKL and OPG were determined via immunoassay. Statistical analysis was performed by Two-Way ANOVA with post-hoc Tukey test at 95% level of significance. Results The CHA and HA microspheres were cytocompatible with both human and murine cells on an in vitro assay. Histological analysis showed the time-dependent increase of newly formed bone in control group characterized by an intense osteoblast activity. In HA and CHA groups, the presence of a slight granulation reaction around the spheres was observed after seven days, which was reduced by the 42nd day. A considerable amount of newly formed bone was observed surrounding the CHA spheres and the biomaterials particles at 42-day time point compared with HA. Histomorphometric analysis showed a significant increase of newly formed bone in CHA group compared with HA after 21 and 42 days from surgery, moreover, CHA showed almost 2-fold greater biosorption than HA at 42 days (two-way ANOVA, p

AbstractNonsyndromic oral clefts are considered a problem of public health in Brazil, presenting a multifactorial etiology that involves genetic and environmental components, such as maternal alcohol consumption. Several candidate genes have been investigated to identify some association with nonsyndromic clefts risk. The epidermal growth factor (EGF) gene is implicated in the normal craniofacial development and its functional +61 A>G polymorphism has been related to cancer susceptibility. It has been suggested that cancer and oral clefts may share the same molecular pathways.Objective Our goal was to evaluate the association between the EGF+61 A>G polymorphism and nonsyndromic oral clefts susceptibility.Material and Methods The case-control study included 218 cleft cases and 253 controls from Brazil. The control group was comprised of individuals without congenital malformations, dental anomalies and family history of clefts. The cleft phenotypes and subphenotypes were determined based on clinical examination. Genomic DNA was extracted from oral mucosa cells obtained by mouthwash. The EGF+61 A>G polymorphism genotype was determined by polymerase chain reaction-restriction fragment length polymorphism.Results We noticed the association between maternal alcohol consumption during pregnancy and cleft occurrence. The A allele and AA genotype were over-represented in cleft cases compared with control group when we considered the bilateral cleft lip with or without cleft palate (CL±P) cases, cleft cases with tooth agenesis and cleft cases presenting family history of cleft, but the differences were not statistically significant. Contradictorily, the G allele was higher in cleft palate only (CP) cases than in control group, showing a borderline p value. Comparing the different cleft phenotypes, we observed statistical differences between CP and CL±P cases. Our data suggest the EGF+61 A>G polymorphism was not related with nonsyndromic oral clefts susceptibility in a Brazilian population, but supported the different genetic background between CL±P and CP. Moreover, we confirmed the potential effect of maternal alcohol intake on cleft risk in our population.

Objective The objective of this study was to investigate the impact of two different commercially available dental implants on osseointegration. The surfaces were sandblasting and acid etching (Group 1) and sandblasting and acid etching, then maintained in an isotonic solution of 0.9% sodium chloride (Group 2). Material and Methods X-ray photoelectron spectroscopy (XPS) was employed for surface chemistry analysis. Surface morphology and topography was investigated by scanning electron microscopy (SEM) and confocal microscopy (CM), respectively. Contact angle analysis (CAA) was employed for wetting evaluation. Bone-implant-contact (BIC) and bone area fraction occupied (BAFO) analysis were performed on thin sections (30 μm) 14 and 28 days after the installation of 10 implants from each group (n=20) in rabbits' tibias. Statistical analysis was performed by ANOVA at the 95% level of significance considering implantation time and implant surface as independent variables. Results Group 2 showed 3-fold less carbon on the surface and a markedly enhanced hydrophilicity compared to Group 1 but a similar surface roughness (p>0.05). BIC and BAFO levels in Group 2 at 14 days were similar to those in Group 1 at 28 days. After 28 days of installation, BIC and BAFO measurements of Group 2 were approximately 1.5-fold greater than in Group 1 (p

Boas Práticas de Laboratório, sistema da qualidade que abrange o processo organizacional e as condições nas quais estudos não clínicos são realizados, visa garantir a uniformidade, consistência, confiabilidade, reprodutibilidade, qualidade e integridade dos testes. O Instituto Brasileiro de Meio Ambiente e dos Recursos Naturais Renováveis introduziu formalmente a Boas Práticas de Laboratório em 1994. Em 1995, o INMETRO iniciou o Programa BPL para reconhecimento e monitoramento baseados em procedimentos, normas, regulamentos administrativos e legais, que estabelecem orientações, políticas e diretrizes para a Coordenação Geral de Acreditação atuar, com total responsabilidade e autoridade, como Autoridade Brasileira de Monitoramento aos princípios das BPL. Estudos BPL são reconhecidos pelos países membros e não membros com adesão plena, aos atos da Organização para a Cooperação e Desenvolvimento Econômico em função do acordo de mútua aceitação de dados e promove redução do número de animais utilizados devido a não repetição dos testes e adoção de métodos alternativos validados. No Brasil, há 31 instalações BPL ativas e cinco realizam testes toxicológicos in vivo. A Resolução Normativa no 17/2014 do Conselho Nacional de Controle da Experimentação Animal estabelece que os testes utilizando animais que tenham métodos alternativos validados reconhecidos pelo Conselho sejam substituídos em até cinco anos, sendo essencial a ampliação da base laboratorial BPL. ---------------------------------------------------------------------------------------- Good Laboratory Practice (GLP), a quality system covering the organizational process and the conditions under which non-clinical studies are conducted, aims to ensure uniformity, consistency, reliability, reproducibility, quality, and integrity of the safety tests. The Brazilian Institute of Environment and Renewable Natural Resources formally introduced GLP in 1994. INMETRO initiated the GLP Program in 1995 for recognition and tracking on the basis of procedures, regulations, administrative and legal rules that establish guidelines, policies and directions to act with full responsibility and authority as the Brazilian monitoring authority to the principles of GLP. GLP studies are recognized by members and non-member countries with full membership to act according to the Organisation for Economic Co-operation and Development (OECD) Mutual Acceptance of Data (MAD) agreement and promote reduction in the number of animals used because of non-repetition of tests and adoption of validated alternative methods. In Brazil, there are 31 active GLP facilities, of which 5 perform in vivo tests. Normative Resolution 17/2014 of the National Council for the Control of Animal Experimentation establishes that animal tests that have validated alternative methods recognized by the Council will be replaced within 5 years with the expansion of BPL-based laboratories.

A biotecnologia aplicada à saúde necessita de células humanas para controle de qua-lidade de produtos e para análise toxicológica das moléculas que entram em contato com o corpo humano. Métodos alternativos validados promovem redução e substituição do uso de animais nos ensaios toxicológicos, mas a legislação brasileira referente ao uso de material biológico humano não prevê disponibilização de células com qualidade controlada e certificada.A análise crítica da legislação brasileira sobre vias de acesso legal a materiais bio-lógicos humanos para obtenção, caracterização e disponibilização de células humanas, abrangendo o período da Constituição Federal de 1988 até o mês de maio de 2014, evidencia que a sociedade Brasileira carece de regulamentação para coleta e uso de material biológico humano incluindo o fornecimento de células para fins terapêuticos ou para utilização na aplicação dos métodos alternativos.Propomos como modelo para disponibilização de materiais biológicos humanos como células, tecidos, órgãos ou partes do corpo humano para fins de pesquisa, ensaios toxi-cológicos e uso terapêutico o mesmo modelo de oferta do excedente de sangue e seus derivados. ------------------------------------------------------------------------------ Biotechnology applied to health requires human cells for quality controls of products and for toxicological assessment of molecules that enter in contact with human body. Validated alternative methods allowed reduction and/or replacement of animal use in toxicology, but the Brazilian legislation on the use of biological materials of human ori-gin does not provide human cells with controlled and certified quality.The critical analysis conducted in the Brazilian’ legislation on legal ways of access to human biological materials for obtaining, characterization and availability of hu-man cells, from the period of the Federal Constitution in 1988 until May 2014, showed that Brazilian society lacks rules for collection and use of human biological materials, including supply of cells, either for therapeutic use or for in vitro assays including the alternative methods for toxicology.We propose a model for providing human biological materials such as cells, tissues, organs or body parts for research, toxicological or therapeutic use similar to the model of the surplus production of blood and its derivatives.

O objetivo foi realizar um estudo epidemiológico dos pacientes com feridas crônicas, com descrição clínica e dos produtos utilizados no tratamento. Estudo quantitativo com entrevista e exame clínico de 186 pacientes atendidos no Ambulatório de Reparo de Feridas do hospital universitário em 2010. Os resultados estão de acordo com estudos internacionais, o maior percentual de pacientes está na faixa etária entre 57-69 anos (28%), é do sexo feminino (54%) e apresenta comorbidades como hipertensão arterial e diabetes (73%). A maior parte tem apenas uma ferida (65%) de etiologia venosa (51%). As bordas das lesões são maceradas (46%), o leito granulado (40%), com exsudato seroso (59%) e sem odor fétido (89%). Os produtos mais utilizados foram o hidrogel (32%) e os ácidos graxos essenciais (26%). Os dados apontam a importância de considerar as características clínicas do paciente e da ferida para se obter resultados positivos no tratamento. ABSTRACT: This research set out to conduct an epidemiologic study of patients with chronic wounds. It aimed at providing both a clinical description and a description of the products used in the treatment. A quantitative study with interview and clinical examination of 186 patients assisted at the Wound Repair Ambulatory of the university hospital in 2010. Results are in compliance with international studies. Highest rates are found in patients aged 57 to 69 years (28%), females (54%), and with comorbidity such as high blood pressure and diabetes (73%). Most of them have just one wound (65%) of venous etiology (51%). The edges of the lesions are macerated (46%), the bed is granulated (40%), with serous exudate (59%) with no fetid odor (89%). Products with highest use were hydrogel (32%) and essential fatty acids (26%). Data shows the relevance of valuing both the patients’ clinical characteristics and those of the wound to obtain positive results in the treatment. RESUMEN: El objetivo del presente estudio fue hacer un perfil epidemiológico de los pacientes con heridas crónicas, haciendo una descripción clínica y enumerando los productos utilizados durante el tratamiento. Se trata de un estúdio cuantitativo con la entrevista y el examen clínico con 186 pacientes bajo tratamiento en el Ambulatorio para Curación de Heridas del hospital universitario en 2010. Los resultados están de acuerdo con estudios internacionales, la mayor parte de los pacientes tienen edades comprendidas entre 57-60 años (28%), son mujeres (54%) y presentan comorbilidad como hipertensión arterial y diabetes (73%). La gran mayoría tiene sólo una herida (65%) de origen venoso (51%). Lesiones con bordes maceradas (46%), con fondo granulado (40%), con exudado seroso (59%) y sin olor fétido (89%). Los productos más utilizados fueron el hidrogel (32%) y los ácidos grasos esenciales (26%). Los datos recolectados enfatizan la importancia de considerar a cada paciente y su herida correspondiente para lograr que el tratamiento tenga resultados positivos.

The relationship between metrology, nanotechnology and nanoscience and sanitary regulation is discussed from the point of view of its importance and the interrelationship between the themes for the development of products and services involving nanotech-nology. The discussion involves the main techniques for measuring dimensional, chemical and biological properties of materials, and presents some of the challenges for the future. Issues such as processes of standardization and regulation in Europe, U.S. and Brazil are also addressed, providing an overview of how these processes are related to sanitary regulation.

ObjectiveThe aim of this study was to produce dense granules of tricalcium phosphate (β-TCP) and magnesium (Mg) substituted β-TCP, also known as β-TCMP (Mg/Ca=0.15 mol), in order to evaluate the impact of Mg incorporation on the physicochemical parameters and in vitro biocompatibility of this novel material.Material and MethodsThe materials were characterized using X-ray diffraction (XRD), infrared spectroscopy (FTIR), electron microscopy and inductively coupled plasma (ICP). Biocompatibility was assayed according to ISO 10993-12:2007 and 7405:2008, by two different tests of cell survival and integrity (XTT and CVDE).ResultsThe XRD profile presented the main peaks of β-TCP (JCPDS 090169) and β-TCMP (JCPDS 130404). The characteristic absorption bands of TCP were also identified by FTIR. The ICP results of β-TCMP granules extract showed a precipitation of calcium and release of Mg into the culture medium. Regarding the cytotoxicity assays, β-TCMP dense granules did not significantly affect the mitochondrial activity and relative cell density in relation to β-TCP dense granules, despite the release of Mg from granules into the cell culture medium.Conclusionβ-TCMP granules were successfully produced and were able to release Mg into media without cytotoxicity, indicating the suitability of this promising material for further biological studies on its adequacy for bone therapy.

The present report aimed to study an uncommon case of a pair of twins that presented a discordant dental phenotype. Family investigation, clinical, radiographic examination and molecular analysis were performed in both girls. Molecular analysis confirmed the monozygosity by deoxyribonucleic acid chip technology. One twin presented tooth agenesis in left upper lateral incisor and peg-shaped on the contra lateral side while the other twin had no dental alterations. The dental casts study employed digital caliper to compare morphological dimensions and showed alteration only in peg-shaped tooth. In conclusion, this study provide support that one or more mutated gene could cause discordances in dental phenotype in these monozygotic twins.

OBJECTIVE: The aim of this study was to evaluate the effect of oral tamoxifen treatment on the number of myofibroblasts present during the healing process after experimental bile duct injury. METHODS: The sample consisted of 16 pigs that were divided into two groups (the control and study groups). Incisions and suturing of the bile ducts were performed in the two groups. Tamoxifen (20 mg/day) was administered only to the study group. The animals were sacrificed after 30 days. Quantification of myofibroblasts in the biliary ducts was made through immunohistochemistry analysis using anti-alpha smooth muscle actin of the smooth muscle antibody. Immunohistochemical quantification was performed using a digital image system. RESULTS: In the animals treated with tamoxifen (20 mg/day), there was a significant reduction in immunostaining for alpha smooth muscle actin compared with the control group (0.1155 vs. 0.2021, p = 0.046). CONCLUSION: Tamoxifen reduced the expression of alpha smooth muscle actin in the healing tissue after bile duct injury, suggesting a decrease in myofibroblasts in the scarred area of the pig biliary tract. These data suggest that tamoxifen could be used in the prevention of biliary tract stenosis after bile duct surgeries.

O objetivo do presente trabalho foi comparar e analisar os requisitos necessários para registro e as ações de tecnovigilância para implantes dentários nos EUA, na União Europeia e no Brasil. Após análise da literatura e das principais normas em vigor, observou-se a preocupação com o controle de riscos e a prevenção de falhas no uso dos implantes dentários. Nos EUA, o sistema de registro e tecnovigilância é centralizado e se verificam problemas de subnotificação e falhas na análise dos relatórios de notificação, bem como um intervalo de tempo longo entre a identificação dos problemas e a ação devido à extensão do processo administrativo. Na União Europeia, os poucos estudos identificados sugerem que o sistema regulatório oferece riscos aos pacientes devido à ausência de transparência entre os Órgãos Notificadores e à dificuldade em se articular a tecnovigilância entre os países. No Brasil, a tecnovigilância é centralizada, porém ainda é incipiente. O envelhecimento da população promove forte demanda por reabilitação oral dos pacientes, sobretudo os carentes, prevista no programa Brasil Sorridente. A demanda pelo serviço oferece uma oportunidade de expansão do mercado, mas detecta-se risco de entrada de produtos de baixa qualidade. Neste contexto, o aprimoramento das atividades de tecnovigilância de implantes dentários é necessário.

Abstract The aim of this study is to evaluate the biocompatibility and osteoconductivity in surgical defects of sheep tibias filled with 1% strontium-containing nanostructured hydroxyapatite microspheres (SrHA), stoichiometric hydroxyapatite without strontium microspheres (HA), or blood clots. Santa Ines sheep were subjected to three perforations on the medial side of the left tibia. The biomaterials were characterized by X-ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) before implantation and by X-Ray Microfluorescence (µFRX) and Scanning Electron Microscopy (SEM) after sheep tibias implantation. Surgical defects were filled with blood clots (control), SrHA (Group 1) or HA (Group 2). After 30 days, 5-µm bone blocks were obtained for histological evaluation, and the blocks obtained from 1 animal were embedded in methylmethacrylate for undecalcified sections. Mononuclear inflammatory infiltrate remained mild in all experimental groups. Giant cells were observed surrounding biomaterials particles of both groups and areas of bone formation were detected in close contact with biomaterials. All groups showed newly formed bone from the periphery to the center of the defects, which the control, HA and SrHA presented 36.4% (± 21.8), 31.2% (± 14.7) and 26.2% (± 12.9) of newly formed bone density, respectively, not presenting statistical differences. In addition, the connective tissue density did not show any significant between groups. The SrHA showing a higher volume density of biomaterial (51.2 ± 14.1) present in the defect compared to HA (32.6 ± 8.5) after 30 days (p = 0.03). Microspheres containing 1% SrHA or HA can be considered biocompatible, have osteoconductive properties and may be useful biomaterials for clinical applications.

PURPOSE: To verify the effects of tibolone administration on trabecular and cortical bone of ovariectomized female rats by computed radiography system (CRS). METHODS: The experiment was performed on two groups of rats previously ovariectomized, one received tibolone (OVX+T) while the other did not (OVX), those groups were compared to a control group (C) not ovariectomized. Tibolone administration (1mg/day) began thirty days after the ovariectomy and the treatment remained for five months. At last, the animals were euthanized and femurs and tibias collected. Computed radiographies of the bones were obtained and the digital images were used to determine the bone optical density and cortical thickness on every group. All results were statistically evaluated with significance set at POBJETIVO: Verificar o efeito da administração de tibolona no tecido ósseo cortical e trabecular de ratas castradas através de radiografia computadorizada. MÉTODOS: O experimento foi realizado em dois grupos de ratas previamente ooforectomizadas, onde um grupo recebeu tibolona (OVX+T) e o outro não (OVX). Esses grupos foram comparados a um grupo controle (C) não ooforectomizado. A administração de tibolona (1mg/dia) começou trinta dias após a ooforectomia e o tratamento teve duração de cinco meses. No final, os animais foram mortos e fêmures e tibias coletados. As radiografias computadorizadas dos ossos foram obtidas e as imagens digitais usadas para determinar a densidade óssea e a espessura cortical em todos os grupos. Todos os resultados foram avaliados estatisticamente com significância estabelecida a 5%. RESULTADOS: A administração de tibolona mostrou ser benéfica apenas para análise densitométrica da cabeça do fêmur, apresentando maiores valores de densidade comparada ao grupo OVX. Nenhuma diferença significativa foi encontrada para espessura óssea cortical. CONCLUSÃO: A ooforectomia ocasionou perda óssea nas regiões analisadas e a tibolona administrada, em dose elevada e durante um longo período, mostrou não ser totalmente benéfica, porém preservou a massa óssea na cabeça femoral.

OBJETIVO: Analisar a segurança e a eficácia da infusão percutânea no foco da pseudoartrose do aspirado de medula óssea total e da infusão de células mononucleares purificadas e concentradas. MÉTODOS: Foram tratados seis pacientes portadores de pseudoartrose de tíbia ou de fêmur. Quatro receberam infusão do aspirado de medula óssea autóloga total obtida da crista ilíaca e dois receberam o aspirado de medula óssea autóloga processada com Sepax®. Não foi alterado o método de fixação primária ou exposto o foco da pseudoartrose. Realizou-se exame físico e avaliação radiográfica 2, 4 e 6 meses após o procedimento. Após a consolidação, foi avaliado o grau de satisfação do paciente. RESULTADOS: Não verificamos qualquer complicação decorrente dos procedimentos. No primeiro grupo (aspirado total) a consolidação foi obtida entre três e vinte e quatro semanas e, no segundo grupo (Sepax®), entre 12 e 16 semanas. O grau de satisfação dos pacientes teve a média aumentada de 2,75 para 9 no grupo I e de 1 para 8,5 no grupo II (p=0,0156). CONCLUSÃO: Concluímos que o tratamento das pseudoartroses com os métodos avaliados mostraram-se eficazes e seguros independente do método de estabilização utilizado. Nível de Evidência II, Estudo Prospectivo Comparativo.OBJECTIVE: To assess the safety and efficiency of cell therapy for pseudarthrosis. Implant of the bone marrow aspirate was compared to mononuclear cells purified extemporaneously using the Sepax® equipment. METHODS: Six patients with nonunion of the tibia or femur were treated. Four received a percutaneous infusion of autologous bone marrow aspirated from the iliac crest, and two received autologous bone marrow mononuclear cells separated from the aspirate with the Sepax®. The primary fixation method was unchanged, and the nonunion focus was not exposed. Physical examination and radiographies were performed 2, 4 and 6 months after the treatment by the same physician. After consolidation of the fracture the satisfaction of the patients was estimated using the adapted QALY scale. RESULTS: No complications occurred as a result of the referred procedures. Bone consolidation was obtained in all cases within 3 to 24 weeks. The degree of patient satisfaction before and after bone consolidation was assessed, with the average value increasing from two to nine (p=0.0156). CONCLUSION: We conclude that the proposed method is effective and safe for the treatment of nonunion of long bones regardless of the stabilization method used. Level of Evidence II, Prospective Comparative Study.

ABSTRACT Objective: The aim of this study was to evaluate the osteogenic potential of human umbilical cord blood-derived osteoprogenitor cells and to prove its applicability as a promising candidate for cell-based therapeutics for bone repair. Methods: Primary cultures of human umbilical blood cord adherent cells were expanded in vitro until passage 2 and seeded for osteodifferentiation study. Morphological (light microscopy), cytochemical (Von Kossa's method), and functional analyses (calcium level, alkaline phosphatase activity, and total protein content in cell culture) were carried out 7, 14, 21, and 28 days after the osteoinduction protocol. Results: The proliferative step showed colony-forming units in 7 days. After osteoinduction, cuboidal cellular morphology similar to osteoblasts at 14 days and mineralization nodules and biochemical changes (increased alkaline phosphatase level and calcium deposits) at 21 days confirmed the osteodifferentiation process. Conclusion: Cell culture of human umbilical blood cord is a reliable technique, constituting itself as an alternative source of osteoprogenitor cells for experimental needs. More animal tests and clinical trials must be carried out to validate its use and to establish quality control of future autologous or allogeneic cell-based therapy aimed at bone repair.

The aim of this work was to produce hydroxyapatite (HA) granules containing 0, 0.5, 1 and 5 mol. (%) of strontium (Sr), evaluate the physico-chemical properties and also the cytotoxicity by three different parameters of cell viability (ISO 10993-5, 10993-12). The physico-chemical characterization was carried out by using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and X-ray fluorescence (XRF). The XRD profile presented the main peaks of HA (JCPDS 860740) and the absorption bands of HA were identified by FTIR. The XRF results showed that the strontium concentration was close to the theoretical value. Regarding the cytotoxicity assays, the incorporation of strontium up to 5 mol. (%) to the HA did not affected dehydrogenase activity (XTT, 2,3-bis[2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide), membrane integrity (neutral red uptake) or DNA contend (incorporation of crystal violet), in relation to HA alone. In conclusion, hydroxyapatite containing from 0.5 to 5 mol. (%) of Sr was successfully produced and presented no cytotoxicity.

OBJECTIVE: The physicochemical properties of hydroxyapatite (HA) granules were observed to affect the biological behavior of graft materials. The aim of this work was to analyze the tissue response of two HA granules with different crystallinity and Ca/P ratio in vivo. MATERIAL AND METHODS: The HA granules were produced in the Biomaterials Laboratory (COPPE/UFRJ). The testing materials were HA granules presenting a Ca/P molar ratio of 1.60 and 28% crystallinity (HA-1), and a Ca/P molar ratio of 1.67 and 70% crystallinity (HA-2). Both HAs were implanted into a critical-size calvaria rat defects. RESULTS: To note, in the control group, the bone defects were filled with blood clot only. Descriptive and histomorphometric analyses after 1, 3, and 6 months postoperatively showed mild inflammatory infiltrate, mainly comprising macrophage-like and multinucleated giant cells, and an increase in the volume density of the fibrous tissues (p

The presence of supernumerary teeth (ST) is a dental developmental anomaly of patterning and morphogenesis. Its variability of morphology, location and developmental timing can shed light on its etiology. In this work we report ST patterns. Orthopantomograms of 1,166 pediatric subjects were examined and the morphology, location and timing of the formation of ST were determined. The frequency of supernumerary teeth in the studied population was 2.3% (n = 27). Twenty-five subjects presented one ST. Maxilla midline was the most commonly affected region (nine cases). We noted high incidence of conical morphology in the midline region. Only teeth with tuberculate morphology presented delayed formation. ST in the midline region occurred more often in males whereas ST in the incisor region were more common in females. In conclusion, ST patterns vary depending on gender.

The incorporation of zinc onto biomaterials may improve their biological properties, since it is an essential trace element, involved on important steps of bone remodeling. The aim of this work was to evaluate the in vivo biocompatibility of previously characterized hydroxyapatite granules incorporated with 5% zinc (ZnHA), through a subcutaneous grafting test. Granules produced from powders of ZnHA or stoichiometric HA were subcutaneously grafted onto Balb/c mice, and histomorphometrical analysis was performed at 7, 14, 21, 28 or 60 days after grafting. HA and ZnHA induced a similar foreign body reaction, with formation of granulome and the presence of a fibrous capsule. Granulocytes were virtually absent, and agranulocytes decreased with time. ZnHA treated samples presented faster reduction on multinucleated giant cells and increase on observed angiogenesis, as compared to HA. It could be concluded that ZnHA granules are biocompatible. Further study should better address its potential use for bone therapy.

INTRODUÇÃO E OBJETIVO: O efeito da tibolona utilizada em alta dose e por tempo prolongado foi analisado mediante estudo histomorfométrico de tíbias e fêmures de ratas castradas. MÉTODOS: O experimento utilizou 20 ratas Wistar, com peso médio de 250 g. Os animais foram distribuídos aleatoriamente em três grupos: ooforectomizado recebendo tibolona (OVX + T) (n = 9), ooforectomizado (OVX) (n = 6) e grupo controle não ooforectomizado (C) (n = 5). Deu-se início ao protocolo experimental 30 dias após a ooforectomia, perdurando por 20 semanas, com administração de tibolona (1 mg/dia) a OVX + T e carboximetilcelulose a OVX. O grupo C não foi submetido a qualquer tratamento. Tíbias e fêmures direitos foram fixados em formol a 10% tamponado, descalcificados e processados para inclusão em parafina. Os cortes histológicos foram corados mediante hematoxilina-eosina para análise histomorfométrica. Mediram-se a espessura cortical e a cavidade medular em cortes transversais de tíbia e fêmur e percentual de porosidade e densidade trabecular em cortes longitudinais de fêmur. RESULTADO E DISCUSSÃO: Não houve diferença estatística entre OVX e OVX + T nas diversas análises. Os resultados demonstram que a tibolona não melhorou de forma significativa a qualidade óssea, porém preservou a massa óssea cortical, nas diáfises femoral e tibial, e o osso trabecular, nos côndilos femorais. O uso prolongado de tibolona em concomitância com alta dose pode ter influenciado tais efeitos, já que estudos recentes têm preconizado a utilização de doses mais baixas na prevenção da osteoporose. CONCLUSÃO: A ooforectomia ocasionou perda óssea nas regiões analisadas; a tibolona, apesar de não ter aumentado a massa óssea, manteve-a em níveis satisfatórios.INTRODUCTION AND OBJECTIVE: The effect of tibolone administered in high dose over a prolonged period was analyzed through histomorphometry of tibia and femur samples from castrated rats. METHODS: The experiment was performed in 20 Wistar rats with average weight of 250 g. The animals were randomly divided into three groups: oophorectomized receiving tibolone (OVX + T) (n = 9), oophorectomized (OVX) (n = 6) and non-oophorectomized as control group (C) (n = 5). The experimental protocol was initiated 30 days after oophorectomy and lasted 20 weeks. Tibolone (1 mg/day) was administered to OVX + T rats and carboxymethyl cellulose to OVX. C rats did not go through any treatment. Right side tibias and femurs were fixed in 10% buffered formalin, decalcified and embedded in paraffin. Histological sections were stained by hematoxylin-eosin for histomorphometric analysis. The cortical thickness and medullary cavity were measured in transverse tibia and femur sections. The percentage of porosity and the trabecular density were determined in longitudinal femur sections. RESULTS AND DISCUSSION: There was no significant statistical difference between OVX and OVX + T in several analyses. The results showed that tibolone did not improve bone quality significantly, although it preserved cortical bone mass in femoral and tibial diaphyses and the trabecular bone in femoral condyles. The administration of tibolone in high dose for a prolonged period may have influenced these effects inasmuch as recent studies have recommended the use of lower doses in osteoporosis prevention. CONCLUSION: Oophorectomy caused bone loss in the analyzed regions. Despite the fact tibolone did not augment bone mass, this was kept at satisfactory levels.

The white New Zealand rabbit (Oryctolagus cuniculus) is frequently used as a model for in vivo studies. However, information on precautions when using this animal as an experimental model is limited. This review of the literature covers the gamut from the selection of the animal model all the way to its death, and describes procedures for transporting, raising, breeding, housing, administering anesthesia and handling so as to rationalize the utilization of this species while exploiting its unique characteristics. Based upon the literature and our own experience with white New Zealand rabbits, we conclude that the rabbit is an adequate model for experimental surgery.O coelho branco da Nova Zelândia (Oryctolagus cuniculus) é freqüentemente utilizado como modelo em estudos in vivo. Contudo, as informações referentes aos cuidados no emprego deste animal como modelo experimental são limitadas. Esta revisão da literatura pretende rever a literatura desde a seleção do modelo animal até a sua morte, enfatizando, os procedimentos para transporte, criação, reprodução, comportamento, acomodação, anestesia e manejo dos animais, de forma a racionalizar a utilização desses animais reconhecendo as características próprias dessa espécie. Conclui-se que o coelho constitui um modelo adequado e viável para cirurgia experimental.

The objective of the present study was to evaluate the quality and intensity of the tissue response to two synthetic hydroxyapatites implanted in critical defects in the skulls of rats. Sixty animals were divided into three experimental groups: I (control), II (HA-1 = HA with 28% crystallinity) and III (HA-2 = HA with 70% crystallinity). They were sacrificed 1, 3, 6, and 9 months after implantation (n = 5 individuals per group/period). Histomorphometric analysis included i) counting of polymorphonuclear leucocytes, mast cells, macrophages and foreign body multinucleated giant cells stained with anti-lysozyme; ii) microvascular density stained with anti-Factor VIII and iii) degree of cell proliferation stained with anti-PCNA. There were no significant differences between the experimental groups in either the quality or quantity of cells in the inflammatory infiltrate, or the degree of angiogenesis and cell proliferation. We conclude that HA-1 and HA-2 are biocompatible and that the physico-chemical differences of these biomaterials did not affect cellular response.

OBJETIVO: Os xenoenxertos são uma alternativa aos enxertos autogênicos e devem ser osteocondutores e biocompatíveis. Um estudo recente demonstrou que as características físicas e químicas das hidroxiapatitas encontradas no comércio não são condizentes com as descrições dos fabricantes. Este estudo avalia a biocompatibilidade e a osteocondução de um xenoenxerto derivado de osso medular bovino. MÉTODOS: Quinze coelhos adultos, pesando entre 2.500g e 3.000g cada um, foram anestesiados e submetidos a procedimentos cirúrgicos para criar três perfurações na tíbia, com 2 mm de diâmetro. Esses orifícios foram preenchidos com coágulo sanguineo, Osseus® e Bio-Oss®. Os animais foram sacrificados depois de 7, 14 e 28 dias. RESULTADOS: A análise histopatológica da interface de osso e biomaterial mostrou ligeira resposta inflamatória depois de 7 dias, que esteve ausente nos períodos subsequentes. Ambos os materiais foram parcialmente substituídos por tecido ósseo diretamente em contato com a superfície dos materiais, sem ocorrência de fibrose. CONCLUSÃO: Concluímos que ambos os materiais são biocompatíveis e absorvíveis, o que permite progressiva aposição óssea na superfície durante todo o período de avaliação.OBJECTIVE: Xenografts are an alternative to autogenous grafts and must be osteoconductive and biocompatible. A recent study has demonstrated that the physical and chemical characteristics of commercially available hydroxyapatites do not fit the manufacturers' descriptions. This study evaluates the biocompatibility and osteoconduction of a xenograft derived from bovine medullary bone. METHODS: Fifteen adult rabbits weighing between 2,500 g and 3,000 g each were anesthetized and subjected to surgical procedures to create three perforations in the tibia, with a diameter of 2 mm. These were filled with blood clot, Osseus® and Bio-Oss®. The animals were euthanized after 7, 14 and 28 days. RESULTS: Histopathological analysis of the interface between the bone and the biomaterial showed a slight inflammatory response after 7 days, which was absent in the subsequent periods. Both materials were partially replaced by bone tissue directly in contact with the surface of the materials, without the occurrence of fibrosis. CONCLUSION: We concluded that both materials are biocompatible and absorbable, allowing for progressive bone apposition on the surface throughout the evaluation period.

Mercury, as any other heavy metal, may cause environmental damages due to its accumulation and biotransformation. Dental offices, whether private or institutional, use dental amalgam as a restorative material on a daily basis. Dental amalgam is composed of mercury (50%), silver (30%) and other metals. Approximately 30% of the amalgam prepared in dental offices (0.6 g per capsule) are wasted and inadequately discarded without any treatment. Methods for mercury recovery have been proposed previously, using high temperatures through exposure to direct flame (650°C), long processing time, and hazardous reagents as potassium cyanide. The purpose of this study was to develop a method to replace the direct flame by an electrical mantle in the process of mercury recovery. Results showed an average mercury recovery of 90% from 2 kg of amalgam after 30 minutes of processing time, thus optimizing the procedure. The proposed modifications allowed a significant reduction in processing time and a mercury recovery with high purity. The modified process also provided minimization of operator exposure to physical, chemical and ergonomic hazards, representing a technological advance compared to the risks inherent to the original method. It also provided environmental health and economy of energy resources by replacing a finite energy source (fossil and organic) by a more environmentally appropriate electric source, resulting in significant improvement of the procedure for mercury recovery from dental amalgam.

Calcium phosphate salts, or more specifically hydroxyapatite, are products of great interest in the fields of medical and dental science due to their biocompatibility and osteoconduction property. Deproteinized xenografts are primarily constituted of natural apatites, sintered or not. Variations in the industrial process may affect physicochemical properties and, therefore, the biological outcome. The purpose of this work was to characterize the physical and chemical properties of deproteinized xenogenic biomaterials, Bio-Oss (Geistlich Biomaterials, Wolhuser, Switzerland) and Gen-Ox (Baumer S.A., Brazil), widely used as bone grafts. Scanning electron microscopy, infrared region spectroscopy, X-ray diffraction, thermogravimetry and degradation analysis were conducted. The results show that both materials presented porous granules, composed of crystalline hydroxyapatite without apparent presence of other phases. Bio-Oss presented greater dissolution in Tris-HCl than Gen-Ox in the degradation test, possibly due to the low crystallinity and the presence of organic residues. In conclusion, both commercial materials are hydroxyapatite compounds, Bio-Oss being less crystalline than Gen-Ox and, therefore, more prone to degradation.

PURPOSE: To investigate the effect of bovine bone morphogenetic proteins (bBMPs) bound to hydroxyapatite plus collagen in the healing of unstable radius fractures. METHODS: A transverse fracture was induced at the mid of the diaphysis in both radii on 15 Norfolk rabbits with average age of 5.5 months and 3.5kg. A mixture of bBMPs bound to thin powdered hydroxyapatite (bBMP-HA) and bovine collagen as agglutinant was applied to the right radius fracture site. The left radius fracture was considered control and no treatment was used. After 30, 60 and 90 days (5 rabbits/period) the rabbits were euthanized and the radii were collected for histological analysis. RESULTS: The descriptive histological analysis revealed that repair was similar for both forelimbs. The histomorphometric analysis showed that the mean area of newly formed bone was 867442.16 mm², 938743.00 mm² and 779621.06 mm² for the control forelimbs, and 841118.47 mm², 788038.76mm² and 618587.24 mm² for the treated forelimbs at 30, 60 and 90 days, respectively. Thus the newly formed bone area was 12.17% larger in the forelimbs treated with bBMP-HA/collagen than in the control forelimbs (pOBJETIVO: Investigar a influência de Proteínas Morfogenéticas Ósseas de origem bovina (bBMPs) ligadas a hidroxiapatita mais colágeno na consolidação de fraturas instáveis do rádio. MÉTODOS: Em 15 coelhos com aproximadamente 5,5 meses de idade e peso médio de 3,5kg foi realizada uma fratura transversa na porção média da diáfise do rádio de ambos os membros. Na fratura do rádio direito foi aplicada mistura de bBMPs ligadas à hidroxiapatita (bBMP-HA) e colágeno bovino como aglutinante e na do rádio esquerdo, considerada controle, nenhum tratamento foi usado. Os coelhos (cinco por período) foram submetidos à eutanásia aos 30, 60 e 90 dias após a cirurgia para realização do processamento histológico e análise microscópica. RESULTADOS: A análise histológica descritiva revelou que a consolidação foi similar para os membros tratado e controle. Pela análise histomorfométrica, a área de novo osso foi em média 867442,16 mm², 938743.00 mm² e 779621,06 mm² para os membros controles e 841118,47 mm², 788038,76mm² e 618587,24 mm² para os membros tratados, aos 30, 60 e 90 dias, respectivamente. Desta forma, aos 60 dias de pós-operatório a área de novo osso foi 12.17% maior no membro tratado com bBMP-HA/colágeno em relação ao membro controle (p

As far as the periimplant anatomy is considered, the question raised is whether or not healthy periimplant tissues present bleeding on probing (BOP). Aim: To assess if the criterion BOP is strictly related to periimplant disease (PID). Methods: 134 patients were included in this study. All periimplant regions were clinically and radiographically evaluated. Patients were assigned to 3 groups based on radiographic and clinical aspects in the periimplant region: Group A (healthysites) - no signs of mucosal inflammation or bone loss; Group B (mucositis) - red and swollen mucosa, but no radiographic bone loss; Group C (periimplantitis) - radiographically confirmed pathological bone loss. After this classification, all periimplant sulci were probed at 4 sites (mesial, distal, buccal, lingual/palatal). Patients’ mean age was 51.7±12.4 years, 77 women and 57 men, with a total of 486 osseointegrated endosseous implants. Results: Groups A and C showed significant difference in age and implant region distribution (p=0.009 and p=0.008, respectively). After initial clinical and radiographic diagnosis of periimplant status, 33 (20.1%) regions showed BOP in group A. All regions in Group B presented BOP. In Group C, 41 (19.9%) regions showed no BOP. All groups differed significantly considering BOP as diagnosis parameter (p

PURPOSE: To evaluate the osteo-regenerative capacity of two proprietary bone grafting materials, using a segmental defect model in both radial diaphyses of rabbits. METHODS: The right defect was filled with pooled bone morphogenetic proteins (pBMPs) bound to absorbable ultrathin powdered hydroxyapatite (HA) mixed with inorganic and demineralized bone matrix and bone-derived collagen, derived from bovine bone (Group A). The left defect was filled with bovine demineralized bone matrix and pBMPs bound to absorbable ultrathin powdered HA (Group B). In both groups, an absorbable membrane of demineralized bovine cortical was used to retain the biomaterials in the bone defects, and to guide the tissue regeneration. The rabbits were euthanized 30, 90 and 150 days after surgery. Radiographic, tomographic and histologic evaluations were carried out on all specimens. RESULTS: At 30 days, the demineralized cortical bone cover was totally resorbed in both groups. HA was totally resorbed from Group A defects, whereas HA persisted in Group B defects. A prominent foreign body reaction was evident with both products, more pronounced in sections from Group B. At 90 days, the defects in Group B exhibited more new bone than Group A. However, at 150 days after surgery, neither treatment had stimulated complete repair of the defect. CONCLUSION: The partial bone healing of the segmental defect occurred with low or none performance of the biomaterials tested.OBJETIVO: Avaliar a capacidade osteo-regenerativa de dois biomateriais utilizando um modelo de defeito segmentar efetuado nas diáfises do rádio de coelhos. MÉTODOS: O defeito direito foi preenchido com pool de proteínas morfogenéticas ósseas (pBMPs) e hidroxiapatita em pó ultrafina absorvível (HA) combinada com matriz óssea inorgânica desmineralizada e colágeno, derivados do osso bovino (Grupo A). O defeito esquerdo foi preenchido com matriz óssea desmineralizada bovina com pBMPs e hidroxiapatita em pó ultrafina absorvível (Grupo B). Em ambos os defeitos utilizou-se membrana reabsorvível de cortical bovina desmineralizada para reter os biomateriais no defeito ósseo e guiar a regeneração tecidual. Os coelhos foram submetidos à eutanásia aos 30, 90 e 150 dias após a cirurgia. Foram efetuados exames radiográficos, tomográficos e histológicos em todos os espécimes. RESULTADOS: Aos 30 dias de pós-cirúrgico, o osso cortical desmineralizado foi totalmente reabsorvido em ambos os grupos. A HA tinha reabsorvido nos defeitos do Grupo A, mas persistiu nos do Grupo B. Uma reação de corpo estranho foi evidente com ambos os produtos, porém mais pronunciada no Grupo B. Aos 90 dias os defeitos do grupo B tinham mais formação óssea que os do Grupo A. Entretanto, aos 150 dias após a cirurgia, nenhum tratamento havia promovido o completo reparo do defeito. CONCLUSÃO: Os biomateriais testados contribuíram pouco ou quase nada para a reconstituição do defeito segmentar.

Hydroxyapatite (HA) is capable of accepting substitute ions within its lattice, including zinc ions. Zinc is a trace element that activates the osteogenesis of osteoblastic cells and therefore plays an important role in the activity of alkaline phosphatase enzyme. The purpose of this work was to produce and characterize 5% mol Zn bioceramic in granular form (Zn-granules) for clinical applications and compare it with granules made from HA by using the same production route. Granules with addition of porogen agents were produced from powders of HA and zinc-containing HA by uniaxial pressing and heat treatment. The granules were subsequently ground and sieved. The results indicated that zinc contributed to the reduction of sample crystallinity and formed a biphasic structure after calcination at 1200 °C. Additionally, zinc release from granular material may have clinical applications as bone graft.

The tissue response to porous bovine anorganic bone implanted in rat connective tissue was evaluated by subjective light microscopy analysis. Forty rats were divided into two groups: control (empty collagen capsules) and test (collagen capsule filled with 0.1g biomaterial) and killed 10, 20, 30 and 60 days after implantation. At 10 days, intense chronic inflammatory infiltrate consisting mainly of macrophages and inflammatory multinucleated giant cells (IMGC) was observed. Neutrophils, plasma cells and lymphocytes were present in discrete amounts and slowly disappeared along the repair process. Porosity of the material was filled by reaction connective tissue exhibiting IMGC. The fibrosis was more intense after 60 days and clearly higher than the control group. Thus, the material did not cause any severe adverse reactions and did not stimulate the immune system. Based on the results it could be concluded that deproteinized bovine cancelous bone was well tolerated by rat connective tissue.A resposta tecidual ao osso inorgânico bovino medular implantado em subcutâneo de rato foi avaliada por análise subjetiva através de microscopia de luz. Quarenta ratos foram divididos em 2 grupos: controle (cápsulas vazias de colágeno) e teste (cápsulas de colágeno contendo 0,1g do biomaterial) e mortos 10, 20, 30 e 60 dias após a implantação. Histologicamente, aos 10 dias, observou-se infiltrado inflamatório crônico composto por macrófagos e Células Gigantes Multinucleadas Inflamatórias (IMGC). Neutrófilos, plasmócitos e linfócitos estavam presentes de maneira discreta, desaparecendo durante o processo de reparo tecidual. A porosidade do material foi preenchida pelo tecido conjuntivo reacional mostrando as IMGC. A fibrose foi mais intensa aos 60 dias e evidentemente superior ao grupo controle. Entretanto, o material não causou reações adversas severas, não estimulando a resposta imunológica. Baseado nos resultados encontrados, concluímos que o osso inorgânico bovino medular foi bem tolerado pelo tecido conjuntivo de rato.