Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 136
1.
Int J Biol Macromol ; 242(Pt 2): 124875, 2023 Jul 01.
Article En | MEDLINE | ID: mdl-37196726

Biological macromolecules have been significantly used in the medicine due to their certain therapeutic values. Macromolecules have been employed in medical filed in order to enhance, support, and substitute damaged tissues or any other biological function. In the past decade, the biomaterial field has developed considerably because of vast innovations in regenerative medicine, tissue engineering, etc. Different types of biological macromolecules such as natural protein and polysaccharide etc. and synthetic molecules such as metal based, polymer based, and ceramic based etc. have been discussed. These materials can be modified by coatings, fibres, machine parts, films, foams, and fabrics for utilization in biomedical products and other environmental applications. At present, the biological macromolecules can used in different areas like medicine, biology, physics, chemistry, tissue engineering, and materials science. These materials have been used to promote the healing of human tissues, medical implants, bio-sensors and drug delivery, etc. These materials also considered as environmentally sustainable as they are prepared in association with renewable natural resources and living organisms in contrast to non-renewable resources (petrochemicals). In addition, enhanced compatibility, durability and circular economy of biological materials make them highly attractive and innovative for current research.The present review paper summarizes a brief about biological macromolecules, their classification, methods of synthesis, and their role in biomedicine, dyes and herbal products.


Biocompatible Materials , Environmental Health , Biocompatible Materials/chemical synthesis , Biocompatible Materials/classification , Proteins/chemistry , Polysaccharides/chemistry , Humans
2.
J Mater Sci Mater Med ; 32(1): 15, 2021 Jan 21.
Article En | MEDLINE | ID: mdl-33475855

Skeletal muscle is capable of regeneration following minor damage, more significant volumetric muscle loss (VML) however results in permanent functional impairment. Current multimodal treatment methodologies yield variable functional recovery, with reconstructive surgical approaches restricted by limited donor tissue and significant donor morbidity. Tissue-engineered skeletal muscle constructs promise the potential to revolutionise the treatment of VML through the regeneration of functional skeletal muscle. Herein, we review the current status of tissue engineering approaches to VML; firstly the design of biocompatible tissue scaffolds, including recent developments with electroconductive materials. Secondly, we review the progenitor cell populations used to seed scaffolds and their relative merits. Thirdly we review in vitro methods of scaffold functional maturation including the use of three-dimensional bioprinting and bioreactors. Finally, we discuss the technical, regulatory and ethical barriers to clinical translation of this technology. Despite significant advances in areas, such as electroactive scaffolds and three-dimensional bioprinting, along with several promising in vivo studies, there remain multiple technical hurdles before translation into clinically impactful therapies can be achieved. Novel strategies for graft vascularisation, and in vitro functional maturation will be of particular importance in order to develop tissue-engineered constructs capable of significant clinical impact.


Muscular Atrophy/therapy , Regenerative Medicine/methods , Tissue Engineering/methods , Animals , Biocompatible Materials/chemistry , Biocompatible Materials/classification , Biocompatible Materials/therapeutic use , Humans , Muscle, Skeletal/pathology , Muscle, Skeletal/physiology , Muscular Atrophy/physiopathology , Regeneration/physiology , Tissue Scaffolds/chemistry , Tissue Scaffolds/classification
3.
In. Estapé Viana, Gonzalo; Ramos Serena, Sergio Nicolás. Tratamiento laparoscópico de los defectos de la pared abdominal: relato oficial. [Montevideo], Grupo Elis, 2021. p.29-37, ilus.
Monography Es | LILACS, UY-BNMED, BNUY | ID: biblio-1435728
4.
Int J Artif Organs ; 43(2): 69-86, 2020 Feb.
Article En | MEDLINE | ID: mdl-31544576

Bone tissue has the capability to regenerate itself; however, defects of a critical size prevent the bone from regenerating and require additional support. To aid regeneration, bone scaffolds created out of autologous or allograft bone can be used, yet these produce problems such as fast degradation rates, reduced bioactivity, donor site morbidity or the risk of pathogen transmission. The development of bone tissue engineering has been used to create functional alternatives to regenerate bone. This can be achieved by producing bone tissue scaffolds that induce osteoconduction and integration, provide mechanical stability, and either integrate into the bone structure or degrade and are excreted by the body. A range of different biomaterials have been used to this end, each with their own advantages and disadvantages. This review will introduce the requirements of bone tissue engineering, beginning with the regeneration process of bone before exploring the requirements of bone tissue scaffolds. Aspects covered include the manufacturing process as well as the different materials used and the incorporation of bioactive molecules, growth factors and cells.


Biocompatible Materials , Bone Regeneration/physiology , Osseointegration/physiology , Tissue Engineering , Tissue Scaffolds , Biocompatible Materials/classification , Biocompatible Materials/pharmacology , Humans , Tissue Engineering/methods , Tissue Engineering/trends
5.
Mayo Clin Proc ; 94(10): 2099-2116, 2019 10.
Article En | MEDLINE | ID: mdl-31515102

Chronic wound management is an enormous economic strain and quality-of-life issue for patients. Current treatments are ineffective or expensive and invasive. Materials (native and artificial) can act as the basis to enhance wound repair but often fall short of complete healing. The therapeutic index of materials have often been enhanced by combining them with drug or biologic elution technologies. Combination of materials with living drugs (cells) presents a new paradigm for enhancing therapy. Cell material interaction and therapeutic output will depend on variables ascribed to the living drug as well as variables ascribed to the underlying matrix. In this article, we review medical matrices currently approved by the US Food and Drug Administration (FDA) that would likely be the first generation of materials to be used in this manner. Currently there are hundreds of different materials on the market. Identification of the right combinations would benefit from a classification scheme to group materials with similar composition or derivation. We provide a classification scheme and FDA documentation references that should provide researchers and clinicians a starting point for testing these materials in the laboratory and rapidly transitioning cell therapies to the bedside.


Biocompatible Materials/classification , Plastic Surgery Procedures , Tissue Engineering , Tissue Scaffolds/classification , Wound Healing , Humans , United States , United States Food and Drug Administration
6.
Vet Clin North Am Exot Anim Pract ; 22(3): 521-538, 2019 Sep.
Article En | MEDLINE | ID: mdl-31395329

Medical devices are defined as implantable if they are intended to remain in the body after the procedure. In veterinary medicine, use of such devices is marginal but may find some indications. Use in exotic pet medicine is even more challenging due to size restriction and the limited data available. This review focuses on the esophageal and tracheal stent in the case of stricture, ureteral stent and subcutaneous ureteral bypass in the case of ureteral obstruction, permanent urinary diversion in the case of bladder atony, and pacemaker in the case of severe arrythmias. Comparative aspects are developed.


Airway Obstruction/veterinary , Animals, Exotic , Biocompatible Materials/classification , Esophageal Stenosis/veterinary , Pacemaker, Artificial/veterinary , Ureteral Obstruction/veterinary , Airway Obstruction/therapy , Animals , Cats , Cystotomy/instrumentation , Cystotomy/veterinary , Dogs , Esophageal Stenosis/therapy , Female , Ferrets , Humans , Male , Rabbits , Stents , Ureteral Obstruction/therapy , Urinary Diversion
7.
Ther Innov Regul Sci ; 53(1): 120-127, 2019 01.
Article En | MEDLINE | ID: mdl-29756484

Regarding the widespread and ever-increasing applications of biomaterials in different medical fields, their accurate assessment is of great importance. Hence the safety and efficacy of biomaterials is confirmed only through the evaluation process, the way it is done has direct effects on public health. Although every biomaterial undergoes rigorous premarket evaluation, the regulatory agencies receive a considerable number of complications and adverse event reports annually. The main factors that challenge the process of biomaterials evaluation are dissimilar regulations, asynchrony of biomaterials evaluation and biomaterials development, inherent biases of postmarketing data, and cost and timing issues. Several pieces of evidence indicate that current medical device regulations need to be improved so that they can be used more effectively in the evaluation of biomaterials. This article provides suggested conceptual refinements and practical reforms to increase the efficiency and effectiveness of the existing regulations. The main focus of the article is on strategies for evaluating biomaterials in US, and then in EU.


Biocompatible Materials , Equipment Safety , Biocompatible Materials/classification , Databases, Factual , European Union , Medical Device Legislation , Product Surveillance, Postmarketing , United States
8.
Ann Biomed Eng ; 46(9): 1229-1240, 2018 Sep.
Article En | MEDLINE | ID: mdl-29869105

In recent years, biodegradable metallic materials have played an important role in biomedical applications. However, as typical for the metal materials, their structure, general properties, preparation technology and biocompatibility are hard to change. Furthermore, biodegradable metals are susceptible to excessive degradation and subsequent disruption of their mechanical integrity; this phenomenon limits the utility of these biomaterials. Therefore, the use of degradable metals, as the base material to prepare metal matrix composite materials, it is an excellent alternative to solve the problems above described. Biodegradable metals can thus be successfully combined with other materials to form biodegradable metallic matrix composites for biomedical applications and functions. The present article describes the processing methods currently available to design biodegradable metal matrix composites for biomedical applications and provides an overview of the current existing biodegradable metal systems. At the end, the manuscript presents and discusses the challenges and future research directions for development of biodegradable metallic matrix composites for biomedical purposes.


Absorbable Implants , Biocompatible Materials , Metals/chemistry , Biocompatible Materials/classification , Biomedical Technology/methods
9.
Angiol Sosud Khir ; 24(1): 29-38, 2018.
Article Ru | MEDLINE | ID: mdl-29688192

Currently, there is great clinical demand for synthetic tissue-engineered cardiovascular prostheses with good long-term patency. Polyurethanes belong to the class of polymers with excellent bio- and hemocompatibility. They are known to possess good mechanical properties, but are prone to processes of degradation in conditions of functioning in living organisms. Attempts at solving this problem have resulted in the development of various new subclasses of polyurethanes such as thermoplastic polyether polyurethanes, polyurethanes with a silicone segment, polycarbonate polyurethanes and nanocomposite polyurethanes. This was accompanied and followed by offering a series of new technologies of production of implantable medical devices such as vascular grafts, heart valves and others. In the presented review, we discuss biological and mechanical properties of modern subclasses of polyurethanes, as well as modern methods of manufacturing implantable medical devices made of polyurethanes, especially small-diameter vascular prostheses.


Blood Vessel Prosthesis/trends , Cardiovascular Surgical Procedures/instrumentation , Heart Valve Prosthesis/trends , Polyurethanes , Biocompatible Materials/classification , Biocompatible Materials/pharmacology , Cardiovascular Surgical Procedures/trends , Humans , Polyurethanes/classification , Polyurethanes/pharmacology
10.
Rev. Asoc. Odontol. Argent ; 105(4): 148-151, dic. 2017. tab, graf
Article Es | LILACS | ID: biblio-973112

Objetivo: determinar la solubilidad del sellador MTA Endosealer Densell en una solución tisular buffer sintética. Materiales y métodos: se utilizó la modificación del Dr. Torabinejad de la especificación #30 de la ADA. Se prepararon 24 anillos de 1,5 mm de espesor por 20 mm de diámetro, utilizando el sellador endodóntico MTA Endosealer Densell. Se colocaron 12 muestras en frascos individuales con 50 ml de una solución tisular buffer. Los 12 discos restantes fueron colocados en frascos individuales con 50 ml de agua destilada. Resultados: el medio de inmersión actuó de forma estadísticamente significativa. Estos resultados opuestos manifiestan ciertos interrogantes y limitaciones a los presentes estudios y a las normativas utilizadas, por lo que es necesario buscar nuevas especificaciones que permitan evaluar en exigencia la calidad y la utilidad clínica de este tipo de materiales a base de agua.


Root Canal Filling Materials/chemistry , Solubility , Chemical Phenomena , Biocompatible Materials/classification , Materials Testing , Data Interpretation, Statistical , Analysis of Variance
11.
Rev. ADM ; 73(3): 116-120, mayo-jun.2016. tab
Article Es | LILACS | ID: lil-795802

En la actualidad existen muchos materiales dentales para la restauraciónestética, sin embargo, su tiempo de vida clínico no se conoce ampliamente. Objetivo: Identificar las publicaciones recientes de los materiales de restauración libre de metal que incluyan estudios clínicos. Metodología: La búsqueda sistemática de la literatura se realizó en bases de datos de PubMed y SciELO; se consideraron publicacionesdel 2010-2015 y que fueran investigaciones clínicas exclusivamente.Las palabras clave utilizadas fueron: Veneer crowns, dental restorationsfree metal, metal free crowns, aesthetic crowns y restauraciones libres de metal, coronas de silicato de litio, tipos de cerámicas. Resultados: Se revisaron 40 artículos y 20 cumplieron con los criterios de selección para la revisión bibliográfica. Todas las restauraciones protésicas libres de metal muestran un desempeño clínico muy similar a los tres años. Las restauraciones de zirconia y disilicato de litio por CAD mostraronel mejor éxito clínico. Conclusión: El éxito clínico de las restauracioneslibres de metal de esta revisión de la literatura muestra que van de un92.7 al 100 por ciento a tres o más años de seguimiento...


Humans , Ceramics/classification , Dental Veneers/statistics & numerical data , Esthetics, Dental , Dental Restoration, Permanent/statistics & numerical data , Zirconium/classification , Lithium Compounds/classification , Computer-Aided Design/methods , Inlays , Biocompatible Materials/classification , Dental Materials/classification , Aluminum Oxide/classification , Data Interpretation, Statistical , Surface Properties
12.
Rev. Fac. Odontol. (B.Aires) ; 31(70): 15-22, ene.-jun. 2016. ilus, tab
Article Es | LILACS | ID: biblio-835573

La ingeniería tisular (IT) ha sido considerada un campo interdisciplinario, aplicando los principios de ciencias de ingeniería y biología para el desarrollo de sustitutos biológicos que restauran, mantienen o mejoran la función tisular. Se basa en el entendimiento de losprincipios del crecimiento tisular, y su aplicación, para producir reemplazo de tejidos para uso clínico. Se consideran determinantes para el éxito de la IT las Stem Cells (células madre), morfógenos y las “scaffolds” (constructos). Poner en práctica dicha disciplina requiere elempleo de estrategias terapéuticas biológicas que apuntan a reemplazar, reparar, mantener y/o mejorar la función tisular. El objetivo de este trabajo, ha sido realizar una actualización sobre nuevos conocimientos emergentes de las últimas publicaciones científicas realizadas en el ámbito de esta nueva disciplina. Para ello se realizó una exhaustiva búsqueda de información en la base de datos de Pubmed. Actualmente, la IT concentra sus esfuerzos en lograr la regeneración de tejidos dentarios y para dentarios, así como en lograr la obtención de una pieza dental completa. Su avance clínico ha sido notable. Se han reportado artículos publicados que ya evidencian su aplicación en periodoncia, cirugía, implantología, rehabilitación oral y endodoncia. Si bien, estrategias de la IT ya se utilizan clínicamente en odontología, su rápido desarrollo se convierte entonces en un gran desafío e incógnita tanto para quienes ejercen la profesión en la actualidad, como para aquellos que se encuentran en plena formación académica. Tomar conocimiento de logros y avances resulta entonces fundamental, ya que podría convertirse en un futuro próximo, en una herramienta de uso habitual.


Tissue engineering (TE) is considered an interdisciplinary field, and applies principles of engineering and biology to develop biologicalsubstitutes that restore, maintain, or improve tissue function. It is based on the application of the principles of tissue growth to producetissue replacement for clinical use. Stem cells, morphogens, and scaffolds are determinant to the success of TE. Implementation of TErequires the use of biological therapeutic strategies aiming to replace, repair, maintain, and/or improve tissue function. The objective ofthe present work was to perform an update of new knowledge presented in recent scientific publications in this field. For this purpose, weconducted an extensive search for information on Pubmed. At present, TE focuses on achieving regeneration of dental and para-dentaltissues, as well as on obtaining a whole tooth. There have been outstanding clinical advances in this field. There are reports showingsuccessful application of TE in periodontics, surgery, implantology, oral rehabilitation and endodontics. Although TE strategies arealready used in dentistry, their rapid development poses a great challenge both to current practitioners and to those who are in the midst oftheir academic training. Gaining an awareness of the achievements and advances in TE is therefore essential, since it could become widelyapplied in the near future.


Humans , Tissue Scaffolds/trends , Tissue Engineering/methods , Dentistry/trends , Stem Cells , Dental Implants , Dental Research , Endodontics , Biocompatible Materials/classification , Biocompatible Materials/therapeutic use , Morphogenesis/physiology , Periodontics , Surgery, Oral , Tissue Culture Techniques/methods
13.
ImplantNewsPerio ; 1(1): 97-103, jan.-fev. 2016.
Article Pt | LILACS, BBO | ID: biblio-847000

Objetivo: analisar sistematicamente, na literatura científica, o uso de substitutos ósseos sintéticos na regeneração óssea para Implantodontia. Material e métodos: uma busca foi realizadas nas bases de dados PubMed, Cochrane, LILACS e SciELO, nos últimos quinze anos, combinando as palavras-chave "regeneração óssea", "materiais biocompatíveis", "implantes dentários", e "materiais aloplásticos". Resultados: Dos 199 artigos inicialmente recuperados, apenas 27 foram selecionados, incluindo revisões sistemáticas/ metanálises (n=2), revisões da literatura (n=1), estudos clínicos (n=9) e pré-clínicos (n=12), relato de caso (n=1) e tese (n=1). Nos modelos animais, o vidro bioativo é capaz de provocar formação óssea à distância, inibir a migração apical do epitélio juncional, e gerar maior deposição de cemento na superfície radicular. Partículas esféricas geram melhor dissolução e integração com o novo osso circundante, e bons resultados são vistos nas técnicas de ROG e RTG. Em um estudo clínico randomizado, o vidro bioativo misturado ao osso autógeno para regeneração de defeitos intraósseos reduziu significativamente a profundidade de sondagem, com ganho de nível clínico de inserção, e resolução dos defeitos já aos seis meses. Nos modelos animais, a tríade hidroxiapatita (HA), beta-fosfato tricálcio (ß-TCP), e fosfato de cálcio bifásico (HA+ ß-TCP) tem se mostrado biocompatível, biorreabsorvível e osteocondutora. Um estudo clínico controlado com HA+ ß-TCP/ membrana revelou melhor preservação óssea vertical e horizontal comparado ao coágulo/membrana, nas TCFCs de seis meses. Regenerações ósseas verticais significativas com estes materiais sintéticos são potencializadas pelo uso dos fatores de crescimento. Conclusão: substitutos ósseos sintéticos demonstram uso promissor para regeneração. Entretanto, a evidência clínica deve ser substancialmente aumentada.


Objective: to systematically analyze in the scientifi c literature the use of synthetic bone substitutes for bone regeneration in implant dentistry. Material and methods: a search was conducted at the PubMed, Cochrane, LILACS and SciELO databases considering the last fi fteen years, and combining the keywords "bone regeneration", "biocompatible materials", "dental implants", and "alloplastic materials". Results: of the 199 articles initially retrieved, only 27 were selected, including systematic reviews/meta-analysis (n=2), literature reviews (n=1), clinical (n=9) and pre-clinical (n=12) studies, case report (n=1) and thesis (n=1). In animal models, the bioactive glass can cause bone formation at distance, inhibit apical migration of the junctional epithelium, and generate greater deposition of cementum over the root surface. Spherical particles generate better dissolution and integration with the new surrounding bone, and good results are seen in the ROG and RTG techniques. In a randomized study, the bioactive glass mixed with autogenous bone to regenerate intra-osseous defects signifi cantly reduced probing depths, with clinical attachment level gains, and defect resolution as early as 6 months. In animal models, the triad hydroxyapatite (HA), beta-tricalcium phosphate (ß-TCP), and biphasic calcium phosphate (HA + ß-TCP) has been shown to be biocompatible, bioresorbable, and osteoconductive. A controlled clinical study with (HA + ß-TCP/membrane) showed better vertical and horizontal bone preservation compared to clot / membrane at the 6 month CBCT images. Also, signifi cant vertical bone regeneration with these synthetic materials is enhanced by the use of growth factors. Conclusion: the synthetic bone substitutes are good candidates for regeneration. However, the level of clinical evidence must be substantially increased.


Humans , Biocompatible Materials/classification , Bone Regeneration , Bone Substitutes/therapeutic use , Dental Implants , Growth Differentiation Factors
14.
Biomater Sci ; 4(1): 25-39, 2016 Jan.
Article En | MEDLINE | ID: mdl-26317131

For the past century, various biomaterials have been used in the treatment of bone defects and fractures. Their role as potential substitutes for human bone grafts increases as donors become scarce. Metals, ceramics and polymers are all materials that confer different advantages to bone scaffold development. For instance, biocompatibility is a highly desirable property for which naturally-derived polymers are renowned. While generally applied separately, the use of biomaterials, in particular natural polymers, is likely to change, as biomaterial research moves towards mixing different types of materials in order to maximize their individual strengths. This review focuses on osteoconductive biocomposite scaffolds which are constructed around natural polymers and their performance at the in vitro/in vivo stages and in clinical trials.


Biocompatible Materials/chemistry , Biocompatible Materials/therapeutic use , Bone Regeneration/physiology , Bone Substitutes/therapeutic use , Ceramics/chemistry , Polymers/chemistry , Biocompatible Materials/classification , Biopolymers , Bone Substitutes/chemistry , Humans
15.
Rev. Ateneo Argent. Odontol ; 55(2): 11-16, 2016. ilus, tab
Article Es | LILACS | ID: biblio-869393

La regeneración ósea guiada es una técnica capaz depromover la neoformación ósea. A través de la aplicaciónde la misma se pueden corregir los defectosóseos como dehiscencias, fenestraciones y defectoscircunferenciales similares a los causados por unaextracción dentaria. Esta técnica permite además, elaumento horizontal y vertical del reborde alveolar.La finalidad de este trabajo es la de realizar una revisiónbibliográfica para evaluar los beneficios de laregeneración ósea guiada en defectos de tipo II.


Guided bone regeneration is a techniquecapable of promoting the new bone formation.The bone defects such as dehiscences andfenestrations circumferential defects similar to thosecaused by a tooth extraction could becorrect through the application of the same.This technique also allows increased horizontaland vertical alveolar ridge. The purpose of thiswork is the carry out of a literature review toevaluate the benefits of bone regenerationguided defects in type II.


Humans , Female , Tooth Socket/physiopathology , Alveolar Ridge Augmentation/instrumentation , Alveolar Ridge Augmentation/methods , Bone Regeneration , Alveolar Bone Loss/therapy , Tooth Extraction/adverse effects , Membranes, Artificial , Biocompatible Materials/classification , Biocompatible Materials/therapeutic use , Surgical Flaps , Bone Transplantation/instrumentation , Bone Transplantation/methods
16.
Rev. Ateneo Argent. Odontol ; 55(2): 19-22, 2016.
Article Es | LILACS | ID: biblio-869394

El propóleos es un producto natural elaborado por las abejas a partir de la secreción que recogen de ciertas especies vegetales y que, luego de modificarlas con sus secreciones salivares, lo transportan al interior de la colmena. Así, el propóleos es responsable directo de garantizar la asepsia de la colmena. Múltiples investigaciones científicas atribuyeronal propóleos propiedades antioxidantes, antibacterianas, antivirales, fungicidas, cicatrizantes, antiinflamatorias, anestésicas, inmunomoduladoras antitumorales. Asimismo, en bastas investigaciones se comprobó que el propóleos actúa inhibiendo la actividad de los Streptococo mutans, principal microorganismo productor de caries dental. Esto motivó la realización de la presente revisión bibliográfica sobre las propiedades y utilización del propóleos en odontología.


Propolis is a natural product made by bees fromcollecting secretion of certain plant speciesand, after modifying their salivary secretions,transported into the hive. So propolis is directlyresponsible for ensuring the cleanliness of the hive.Multiple scientific research attributed to propolisantioxidant, antibacterial, antiviral, fungicide, healing,anti-inflammatory, anesthetic,immunomodulatory and antitumor properties.Also in rough investigations it was foundthat propolis acts by inhibiting the activityof Streptococcus mutans, the main producingmicroorganism tooth decay. This led to therealization of this literature review on theproperties and use of propolis in dentistry.


Humans , Flavonoids/classification , Flavonoids/therapeutic use , Biocompatible Materials/classification , Biocompatible Materials/therapeutic use , Propolis/pharmacology , Propolis/therapeutic use , Dental Caries/therapy , Streptococcal Infections/therapy , Chemical Phenomena
17.
Rev. Asoc. Odontol. Argent ; 103(4): 160-167, dic.2015. ilus, tab
Article Es | LILACS | ID: lil-781815

Evaluar la respuesta del tejido celular subcutáneo de la rata a implantes de conos de Resilon (CRE) y conos de gutapercha (CGP). Materiales y métodos: se implantaron en el tejido celular subcutáneo de ratas, conos de CRE y CGP de medidas similares y conicidad .04. La respuesta de los tejidos circundantes se analizó a los 14 y a los 84 días. La reacción a los materiales implantados fue clasificada en cuatro categorías, en función del grado creciente de inflamación y los resultados fueron sometidos a un análisis estadístico. Resultados: a los 14 días, se observó en contacto con CRE y con CGP una cápsula de tejido fibroso joven de poco espesor, vasos de neoformación y áreas ocupadas por escasas células inflamatorias, especialmente linfocitos y plasmocitos. Sólo tres casos de CRE y dos de CGP presentaron un grado de inflamación mayor en los tejidos circundantes. LUego de 84 días, la reacción fue similar para ambos materiales en todos los especímenes. Los conos estaban rodeados por un tejido conectivo fibroso maduro y denso, de mayor espesor, y escasos linfocitos y plasmocitos remanentes en los tejidos circundantes, con la singularidad de que en áreas aisladas y adyacentes a los CGP se observó presencia de partículas aparentemente liberadas por los conos, fagocitadas por macrófagos. Las diferencias entre CRE y CGP, tanto en un mismo período como entre ambos períodos de observación, no fueron significativas (p>0.05). Conclusión: luego de 84 días, los conos de CRE y CGP no se comportaron como materiales totalmente inertes en el tejido celualr subcutáneo de la rata. La persistencia de algunas células inflamatorias en los tejidos circundantes a los CRE y los CGP y la actividad macrofágica estimulada por la presencia de partículas liberadas por los CGP, sugieren evitar en lo posible la sobreobturación con los conos y mantenerlos dentro de los límites del conducto radicular...


Animals , Rats , Gutta-Percha/chemistry , Biocompatible Materials/classification , Root Canal Filling Materials/chemistry , Subcutaneous Tissue/anatomy & histology , Foreign-Body Reaction , Histological Techniques , Materials Testing , Data Interpretation, Statistical
18.
Rev. ADM ; 72(5): 272-274, sept.-oct. 2015.
Article Es | LILACS | ID: lil-775337

Durante muchos años se han utilizado los postes colados, considerados como un estándar en la odontología protésica, pero presentan limitantes técnicas y mecánicas, ya que exhiben altos módulos de elasticidad y, por lo mismo, imposibilitan la capacidad de disipar las fuerzas con efectividad, lo que significa concentrar tensiones dentro del conducto radicular. Literatura basada en evidencia científica describe a los postes de fibra de vidrio con módulos de elasticidad semejantes o próximos a la dentina, presentando propiedades anisotrópicas, en comparación con los postes tradicionales, que presentan propiedades isotrópicas. Se propone un concepto restaurador que involucra el poste, el cemento y la dentina, constituyendo un complejo homogéneo denominado ®monobloque¼ que permite un mejor comportamiento mecánico benéfico para el remanente dentario


For many years now, cast posts have been regarded as standard in prosthetics despite the technical and mechanical limitations caused by their high moduli of elasticity, which prevent the forces involved from being effectively dissipated and, therefore, concentrate stress within the root canal. Scientifi c evidence-based literature describes fi berglass posts with moduli of elasticity similar to or approaching that of dentin as having anisotropic properties, as opposed to the isotropic properties of traditional posts. We propose a restorative approach that involves the post, the cement, and the dentin, forming a homogeneous complex known as a ®monobloc¼ that enables enhanced mechanical behavior that benefits the remaining tooth structure.


Humans , Biomechanical Phenomena , Dentin/physiology , Dental Restoration, Permanent/trends , Post and Core Technique/trends , Glass/chemistry , Dental Cementum , Tooth, Nonvital/physiopathology , Elastic Modulus , Biocompatible Materials/classification , Tensile Strength
19.
Scanning ; 37(6): 429-37, 2015.
Article En | MEDLINE | ID: mdl-26148576

Topographical features of biomaterials' surfaces are determinant when addressing their application site. Unfortunately up to date there has not been an agreement regarding which surface parameters are more representative in discriminating between materials. Discs (n = 16) of different currently used materials for implant prostheses fabrication, such as cast cobalt-chrome, direct laser metal soldered (DLMS) cobalt-chrome, titanium grade V, zirconia (Y-TZP), E-glass fiber-reinforced composite and polyetheretherketone (PEEK) were manufactured. Nanoscale topographical surface roughness parameters generated by atomic force microscopy (AFM), microscale surface roughness parameters obtained by white light interferometry (WLI) and water angle values obtained by the sessile-water-drop method were analyzed in order to assess which parameter provides the best optimum surface characterization method. Correlations between nanoroughness, microroughness, and hydrophobicity data were performed to achieve the best parameters giving the highest discriminatory power. A subset of six parameters for surface characterization were proposed. AFM and WLI techniques gave complementary information. Wettability did not correlate with any of the nanoroughness parameters while it however showed a weak correlation with microroughness parameters.


Biocompatible Materials/analysis , Biocompatible Materials/classification , Materials Testing/methods , Surface Properties , Hydrophobic and Hydrophilic Interactions , Interferometry , Microscopy, Atomic Force
20.
São Paulo; s.n; 2015. 94 p. ilus, tab. (BR).
Thesis Pt | LILACS, BBO | ID: biblio-871110

A deficiência óssea requer procedimentos restauradores como uso de enxertos e substitutos ósseos para a reabilitação estética e funcional. Com o desenvolvimento dos biomateriais, a biocerâmica à base de fosfato de cálcio tornou-se alternativa promissora para a recomposição de estruturas ósseas, entretanto não apresenta potencial de osteoindução. O material hidróxido de cálcio (Ca(OH)2) demonstra propriedades antibacterianas e capacidade de induzir a formação de tecido ósseo. O objetivo deste trabalho foi avaliar o processo de reparo ósseo proporcionado pelo BTCP e Ca(OH)2 , isolados e associados. Realizou-se experimento em tíbias posteriores de dezoito coelhos. Dois animais receberam marcadores ósseos para fluorescência (alizarina, calceína e tetraciclina), e para cada tíbia foi utilizado um tipo de material de preenchimento (BTCP, Ca(OH)2, BTCP com Ca(OH)2 e sangue como controle); sendo eutanasiados após 56 dias para a análise de fluorescência e histomorfometria. Os 16 coelhos restantes foram aleatoriamente selecionados para receber os quatro materiais de preenchimento. Estes foram eutanasiados nos tempos de 14, 28, 42 e 56 dias para a análise morfológica microscópica com coloração em hematoxilina e eosina. Observou-se formação óssea em todos os grupos, e os que utilizaram BTCP apresentaram atraso para o início da reparação. O sítio preenchido com sangue ocorreu apenas o reparo da estrutura lesada, consistindo na reconstituição da cortical óssea e tecido medular em 28 dias. Aos 56 dias, o grupo de BTCP com Ca(OH)2 apresentou maior formação de trabéculas no interior da tíbia. Na avaliação histomofométrica, o marcador calceína apresentou maiores valores de deposição óssea em relação à alizarina e tetraciclina. Conclui-se que os biomateriais BTCP e Ca(OH)2 estão diretamente envolvidos na formação de tecido ósseo no interior do defeito; a combinação do Ca(OH)2 com BTCP mostrou aumento do potencial de formação óssea; e houve maior deposição óssea no período entre quinta e sexta semana de reparação indicado pelo marcador calceína.


Insufficient bone volume requires restorative procedures such as use of grafts and bone substitutes for cosmetic and functional rehabilitation. The development of biomaterials made available bioceramic based on calcium phosphate that is showing to be promising alternatives for the restoration of bony structures, however it do not has osteoinductive potential. Calcium hydroxide (Ca(OH)2) shows antibacterial properties and induce bone tissue formation as well. The objective of this research was to evaluate the bone healing process promoted by BTCP and Ca(OH)2 isolated or conjugated. The experiment was conducted in posterior rabbit tibiae of 18 animais. Two animais received bone markers (alizarin, calcein, tetracycline) and each of their tibias received a type offiller material (BTCP, Ca(OH)2, BTCP plus Ca(OH)2 and blood as control group), being euthanized after 56 days for the histomorphometry and fluorescence analysis. The remaining 16 rabbits were randomly selected to receive one of the 4 filling materiais. These rabbits were euthanized on 14,28,42 and 56 days for the micromorphological analysis in hematoxylin and eosin slides. The bone formation was observed in ali groups, and who used BTCP had delay to the start of repair. The site filled with blood occurred only repair of the damaged structure, consisting of the reconstitution of the bone cortical and medullary tissue in 28 days. After 56 days, the BTCP group with Ca(OH)2 showed higher trabecular formation inside the tibia. In histomorfometric evaluation, the marker calcein had higher bone deposition values in relation to alizarin and tetracycline. It was concluded that the biomaterials BTCP and Ca(OH)2 are directly involved in the formation of bone tissue; the conjugation of Ca(OH)2 with BTCP increased bone formation potential; and there was greater bone deposition in the period between the fifth and sixth week of repairs indicated by calcein marker.


Animals , Rabbits , Ceramics , Calcium Hydroxide/administration & dosage , Calcium Hydroxide/adverse effects , Biocompatible Materials/classification , Biocompatible Materials/therapeutic use
...