ABSTRACT
The aim of this paper was to synthesize and characterize polymeric scaffolds of Chitosan/Xanthan/Hydroxyapatite-Graphene Oxide nanocomposite associated with mesenchymal stem cells for regenerative dentistry application. The chitosan-xanthan gum (CX) complex was associated with Hydroxyapatite-Graphene Oxide (HA-GO) nanocomposite with different Graphene Oxides (GO) concentration (0.5 wt%; 1.0 wt%; 1.5 wt%). The scaffolds characterizations were performed by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and contact angle. The mechanical properties were assessed by compressive strength. The in vitro bioactivity and the in vitro cytotoxicity test (MTT test) were analyzed as well. The data was submitted to the Normality and Homogeneity tests. In vitro Indirect Cytotoxicity assay data was statistically analyzed by ANOVA two-way, followed by Tukey's test (α = 0.05). Compressive strength and contact angle data were statistically analyzed by one-way ANOVA, followed by Tukey's test (α = 0.05). XRD showed the presence of Hydroxyapatite (HA) peaks in the structures CXHA, CXHAGO 0.5%,1.0% and 1.5%. FT-IR showed amino and carboxylic bands characteristic of CX. Raman spectroscopy analysis evidenced a high quality of the GO. In the TGA it was observed the mass loss associated with the CX degradation by depolymerization. SEM analysis showed pores in the scaffolds, in addition to HA incorporated and adhered to the polymer. Contact angle test showed that scaffolds have a hydrophilic characteristic, with the CX group the highest contact angle and CXHA the lowest (p < 0.05). 1.0 wt% GO significantly increased the compressive strength compared to other compositions. In the bioactivity test, the apatite crystals precipitation on the scaffold surface was observed. MTT test showed high cell viability in CXHAGO 1.0% and CXHAGO 1.5% scaffold. CXHAGO scaffolds are promising for regenerative dentistry application because they have morphological characteristics, mechanical and biological properties favorable for the regeneration process.
Subject(s)
Chitosan , Graphite , Mesenchymal Stem Cells , Chitosan/chemistry , Durapatite/chemistry , Biocompatible Materials/chemistry , Tissue Scaffolds/chemistry , Graphite/chemistry , Porosity , Spectroscopy, Fourier Transform Infrared , Regeneration , Dentin , Tissue Engineering/methodsABSTRACT
OBJECTIVE: To develop a chitosan-xanthan (CX) membrane associated with Hydroxyapatite (HA) and different concentrations of graphene oxide (GO). METHODOLOGY: The CX complex was associated with the hydroxyapatite-graphene oxide (HAGO) nanocomposite in different concentrations. The experimental groups were:1) CX; 2) Chitosan-Xanthan/Hydroxyapatite (CXHA); 3) Chitosan-Xanthan/Hydroxyapatite-Graphene Oxide 0.5% (CXHAGO 0.5%); 4) CXHAGO 1.0%; 5) CXHAGO 1.5%. The membranes characterizations were performed by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy, Scanning Electron Microscopy (SEM), Contact angle, Tensile Strength, in vitro Bioactivity and the in vitro Cell viability (MTT test). The data was submitted to the Normality and Homogeneity tests. In vitro Indirect Cytotoxicity assay data was statistically analyzed by two-way ANOVA and Tukey's test (α = 0.05). Tensile Strength and Contact Angle data were statistically analyzed by one-way ANOVA followed by Tukey's test (α = 0.05). RESULTS: XRD, FTIR and Raman spectroscopy confirmed the characteristic bands of the CX polymeric complex, the phosphate bands related to HA, and the presence of GO. SEM images demonstrated the non-porous and homogeneous surface of membranes. The contact angle test showed the hydrophilic characteristic of all membranes (p > 0.05). CX showed tensile strength significantly higher than other membranes. The apatite deposition was observed in all membranes after performing the bioactivity test. The cell viability of CXHAGO 1.0% and CXHAGO 1.5% was significantly higher than CX. CONCLUSION: The addition of HAGO reduced the mechanical strength of membranes, but improved its cell viability. It demonstrated the potential of CXHAGO membranes to be used in guided bone regeneration therapies.
Subject(s)
Chitosan , Nanocomposites , Chitosan/chemistry , Durapatite/chemistry , Bone Regeneration , Nanocomposites/chemistry , Spectroscopy, Fourier Transform InfraredABSTRACT
O objetivo deste trabalho é apresentar um caso clínico, demonstrando a associação entre diferentes tipos de restaurações e sistemas cerâmicos, na reabilitação do sorriso de uma paciente do gênero feminino com queixas em relação à cor e ao posicionamento dos elementos anteriores superiores. Ao exame clínico constatou-se exposição do metal da coroa metalocerâmica no elemento 21 e escurecimento, mau posicionamento dos elementos 13, 12, 22 e 23, além de diferença de cor entre os dentes. Foi proposto como plano de tratamento a substituição das coroas metalocerâmicas por novas coroas nos elementos 11 e 21, e a confecção de facetas indiretas em cerâmica reforçada por dissilicato de lítio (IPS e-max Press, Ivoclar Vivadent) nos dentes 13, 12, 22 e 23. A associação entre coroas metalocerâmicas e facetas convencionais, mostrou-se uma forma de tratamento efetiva na reabilitação do sorriso, garantindo ao final do tratamento correta seleção de cor, boa adaptação marginal das restaurações, alinhamento adequado e também, bons resultados estéticos e boa função mastigatória, contribuindo para a satisfação da paciente.
The aim of this study is to present a clinical case demonstrating the association between different types of restorations and ceramic systems in the smile rehabilitation of a female patient with complaints about the color and and placement of the maxillary anterior elements. On clinical examination it was found metal exposure of the metal-ceramic crown on element 21, darkening and poor positioning of elements 13,12, 22 and 23, as well as, color difference between the teeth. Was proposed as treatment plan the replacement of metal-ceramic crowns by new crowns in the elements 11 e 21, and the making of indirect veneers in ceramic reinforced by lithium dissilicate (IPS e-max Press, Ivoclar Vivadent) on teeth 13, 12, 22 and 23. The association between metal-ceramic crowns and conventional veneers, proved to be a form of effective treatment in the smile rehabilitation, ensuring in the end of the treatment correct color selection, good marginal adaptation of restorations, proper alignment and also good esthetic results and good chewing function , contributing to patient satisfaction.
ABSTRACT
Dental structure deterioration, like enamel erosion, is caused through dissolution by endogenous or exogenous acid substances in the oral cavities. The demineralization caused exclusively by endogenous acid as the chronic regurgitations and gastric dysfunctions that cause erosive tooth lesions are known as perimolysis. This clinical case report describes the oral rehabilitation of a patient with perymolisis using direct composite resin restorations. This patient had erosive lesions on lingual, incisor, and occlusal surfaces of almost all teeth, a situation which, among other disturbances, caused alteration in vertical dimension of occlusion, muscular pain, and esthetic damage. Multifactorial aspects were applied to diagnosis, planning, and functional and esthetic rehabilitation of anteriorand posterior teeth.
A deterioração estrutural dental, como a erosão do esmalte, é causadapor dissoluções de substâncias ácidas endógenas ou exógenas nas cavidades orais. A desmineralização causada exclusivamente por ácido endógeno como as regurgitações crônicas e disfunções gástricas que causam lesões dentárias erosivas são conhecidos como perimólise. Este relato de caso clínico descreve a reabilitação oral de um paciente com perimólise usando restaurações de resina composta direta. Este paciente apresentava lesões erosivas na língua, incisivos e superfícies oclusais de quase todos os dentes, uma situação que, entre outros distúrbios, causa alteração na dimensão vertical de oclusão, dor muscular e dano estético. Aspectos multifatoriais foram aplicados ao diagnóstico, planejamento e reabilitação funcional e estética dos dentes anteriores e posteriores.
