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In this study, poly (lactic-co-glycolic acid) (PLGA) microparticles loaded with cannabidiol (CBD) were synthesized (PLGA@CBD microparticles) and embedded up to 10 wt% in a chondroitin sulfate/polyvinyl alcohol hydrogel matrix. In vitro chemical, physical, and biological assays were carried out to validate the potential use of the modified hydrogels as biomaterials. The microparticles had spherical morphology and a narrow range of size distribution. CBD encapsulation efficiency was around 52%, loading was approximately 50%. Microparticle addition to the hydrogels caused minor changes in their morphology, FTIR and thermal analyses confirmed these changes. Swelling degree and total porosity were reduced in the presence of microparticles, but similar hydrophilic and degradation in phosphate buffer solution behaviors were observed by all hydrogels. Rupture force and maximum strain at rupture were higher in the modified hydrogels, whereas modulus of elasticity was similar across all materials. Viability of primary human dental pulp cells up to 21 days was generally not influenced by the addition of PLGA@CBD microparticles. The control hydrogel showed no antimicrobial activity against Staphylococcus aureus, whereas hydrogels with 5% and 10% PLGA@CBD microparticles showed inhibition zones. In conclusion, the PLGA@CBD microparticles were fabricated and successfully embedded in a hydrogel matrix. Despite the hydrophobic nature of CBD, the physicochemical and morphological properties were generally similar for the hydrogels with and without the CBD-loaded microparticles. The data reported in this study suggested that this original biomaterial loaded with CBD oil has characteristics that could enable it to be used as a scaffold for tissue/cellular regeneration.
Assuntos
Canabidiol , Humanos , Porosidade , Materiais Biocompatíveis , Bioensaio , HidrogéisRESUMO
Cannabidiol (CBD) has been gaining increased attention in contemporary society but seems to have been little explored in dentistry. This scoping review mapped the scientific and technological scenarios related to the use of CBD in dentistry. Peer-reviewed publications were searched in five international databases, patents were searched in five technological platforms. In total, 11 articles and 13 patents involving CBD in dentistry-related applications were included. The countries contributing to most articles were Brazil (27.3%) and USA (18.2%). The studies involved experiments on animals (63.6%) and/or using bacteria or cells (36.4%), and no clinical study was found. Three different applications of CBD were observed: periodontal therapy (45.4%), aid for bone regeneration (27.3%), and general use in oral therapies (27.3%). Patent inventors were based in China (53.8%) or USA (46.2%). The patent claims were mainly compositions for oral care, tooth whitening, injury repair, antifungal, anti-inflammatory, and analgesic effects. A total of 76.9% of the patents were filed in association with a company. In general, research suggests that CBD has promising biological properties for applications in dentistry, whereas patents indicate that the current interest of industry relies on compositions for oral care. There appears to be extensive room available for research and technological applications of CBD in dentistry.
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STATEMENT OF PROBLEM: Although the clinical use of self-adhesive flowable composite resins is convenient, the decision to use flowable or conventional composite resin remains controversial. PURPOSE: The purpose of this systematic review and meta-analysis was to assess the in vitro bond strength of self-adhesive flowable composite resins to enamel or dentin compared with conventional composite resins using etch-and-rinse or self-etch adhesive systems. MATERIAL AND METHODS: Two independent reviewers performed searches in the PubMed (MEDLINE), Cochrane Wiley, Web of Science, Scopus, and Google Scholar databases for studies reporting on the bond strength of self-adhesive flowable and conventional composite resins to enamel and dentin published from January 2010 up to September 2020. A meta-analysis software program was used for the meta-analysis. Comparisons were conducted using standardized mean differences considering the random-effects model (α=.05). RESULTS: Twenty-two studies were considered for the meta-analysis. Immediate and long-term bond strength to enamel was improved when a conventional composite resin was used in combination with an adhesive system (P<.001). Bond strength to dentin was improved by using an adhesive system in combination with a conventional composite resin (P<.001). CONCLUSIONS: The bond strength of self-adhesive flowable composite resins is lower than that of conventional composite resins, indicating limited ability to bond to enamel and dentin.
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Colagem Dentária , Cimentos de Resina , Cimentos de Resina/química , Dentina/química , Cimentos Dentários , Teste de Materiais , Propriedades de Superfície , Resinas Compostas/uso terapêutico , Resinas Compostas/química , Adesivos Dentinários/químicaRESUMO
Novel poly(vinyl alcohol)/chondroitin sulfate (PVA/CS) composite hydrogels containing hydroxyapatite (HA) or Sr-doped HA (HASr) particles were synthesized by a freeze/thaw method and characterized aiming towards biomedical applications. HA and HASr were synthesized by a wet-precipitation method and added to the composite hydrogels in fractions up to 15 wt%. Physical-chemical characterizations of particles and hydrogels included scanning electron microscopy, energy-dispersive spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetry, porosity, compressive strength/elastic modulus, swelling degree, and cell viability. Particles were irregular in shape and appeared to have narrow size variation. The thermal behavior of composite hydrogels was altered compared to the control (bare) hydrogel. All hydrogels exhibited high porosity. HA/HASr particles reduced total porosity without reducing pore size. The mechanical strength was improved as the fraction of HA or HASr was increased. HASr particles led to a faster water uptake but did not interfere with the total hydrogel swelling capacity. In cell viability essay, increased cell growth (above 120%) was observed in all groups including the control hydrogel, suggesting a bioactive effect. In conclusion, PVA/CS hydrogels containing HA or HASr particles were successfully synthesized and showed promising morphological, mechanical, and swelling properties, which are particularly required for scaffolding.
Assuntos
Materiais Biocompatíveis/química , Sulfatos de Condroitina/química , Durapatita/química , Álcool de Polivinil/química , Estrôncio/química , Materiais Biocompatíveis/síntese química , Sulfatos de Condroitina/síntese química , Força Compressiva , Durapatita/síntese química , Módulo de Elasticidade , Álcool de Polivinil/síntese química , Porosidade , TermogravimetriaRESUMO
Introducción: En la especie humana, las diferencias obedecen a variaciones biológicas ligadas a los caracteres sexuales, conducta socio-cultural y epigenética en cada grupo poblacional. Estas variaciones biológicas entre sexos se analizan desde el punto de vista morfológico. Algunos estudios refieren que la morfometría, relacionando el tamaño y forma del esqueleto humano, conduce a resultados más fidedignos y reproducibles. Objetivo: comparar los caracteres morfológicos y morfométricos de los detalles anatómicos propios de la rama mandibular para determinar el sexo en mandíbulas humanas, en dos poblaciones venezolanas. Materiales e métodos: la muestra fue 16 mandíbulas encontradas como hallazgo fortuito en el 2004 (Población A) y 08 mandíbulas humanas procedentes de la Colección de paleodemográfica, constituida por restos óseos de la población del yacimiento del Valle de Quíbor (Edo. Lara) (Población B). Posteriormente, fueron analizadas morfológico y métricamente, empleando los puntos de referencia anatómicos o PAR/Lamarck, y valoradas en el paquete estadístico SSPS (versión 19). Resultados: la rama mandibular es una muestra confiable para la discriminación sexual, después del análisis morfológico y métrico, de los 16 individuos procedentes de la población A, 07 corresponden con los criterios femeninos y 09 a masculinos. En la muestra de 08 individuos procedente de la población B, se identificaron 03 individuos femeninos y 05 masculinos. Conclusiones: el uso de métodos morfológico e morfométrico siguen siendo necesarios como primer paso para el reconocimiento de individuos en las ciencias forenses. No obstante, fue más efectivo la discriminación sexual mediante los parámetros morfométricos en relación al método morfológico.