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1.
J Endod ; 2021 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-33887309

RESUMEN

INTRODUCTION: Guided tissue regeneration has been considered a promising biological strategy to replace conventional endodontic therapies of teeth with incomplete root formation. Therefore, in the present study, a collagen/gelatin hydrogel either containing dosages of fibronenctin (FN), or not, were developed and assessed concerning their bioactive and chemotactic potential on human apical papilla cells (hAPCs). METHODS: Hydrogels were prepared by varying the ratio of collagen and gelatin (Col/Gel; v/v), and used to establish the following groups: Collagen (positive control); Col/Gel 4:6; Col/Gel 6:4; Col/Gel 8:2. The viability, adhesion and spreading of cells seeded on the hydrogels were evaluated. Different concentrations of FN (0, 5 or 10 µg/mL) were incorporated into the best formulation of the collagen/gelatin hydrogel selected. Then, the hAPCs seeded on the biomaterials were assessed concerning the cell migration, viability, adhesion and spreading, and gene expression of ITGA5, ITGAV, COL1A1 and COL3A1. RESULTS: Col/Gel 8:2 group exhibited better cell viability, adhesion and spreading in comparison with Control. Higher values of hAPCs migration, viability, adhesion, spreading and gene expression of pulp regeneration markers were found, the higher the concentration was of FN incorporated into the collagen/gelatin hydrogel. CONCLUSION: Collagen/gelatin hydrogel with 10 µg/mL of FN had potent bioactive and chemotactic effects on cultured hAPCs.

2.
Dent Mater ; 2021 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-33579532

RESUMEN

OBJECTIVES: To investigate the trans-enamel and trans-dentinal biological effects of treating enamel white spot-like lesions (EWSLs) with resin infiltration components (RICs) on odontoblast-like cells (MDPC-23) and human dental pulp cells (HDPCs). METHODS: EWSLs were induced in 60 enamel/dentin discs (4.0 ± 0.2 mm thick) using S. mutans. The discs were adapted into artificial pulp chambers and MDPC-23 were seeded on the dentin surface. The components of a resin infiltration system (Icon) were applied individually or in combination on the enamel surface as following (n = 10/treatment): Etch, Infiltrant, Etch+Infiltrant, or Etch+Dry+Infiltrant. The application of water or hydrogen peroxide served as negative and positive controls, respectively. After 72 h, MDPC-23 viability was evaluated. The extracts were exposed for 72 h to pre-cultured MDPC-23 and HDPCs in 96-well plates to evaluate cell viability, alkaline phosphatase activity (ALP), mineralized nodule formation (MN), and the expression of inflammatory cytokines (ICs) and mineralization-related genes (MRs). Data were analyzed by ANOVA complemented with Tukey or Games-Howell post-hocs (α = 5%). RESULTS: Cell viability, ALP activity, and MN formation were significantly reduced in response to the RICs, presenting intermediate values compared to positive and negative controls. Likewise, ICs were upregulated, whereas MRs were downregulated. Among the RICs, the Etch component caused the most notorious detrimental effects. SIGNIFICANCE: Resin infiltration of EWSLs negatively affected the metabolism of pulp cells in vitro. Therefore, even though resin infiltration is a micro-invasive therapy for non-cavitated caries in enamel, it should be closely followed up seen that components may diffuse and unbalance pulp homeostasis.

3.
J Biomed Mater Res B Appl Biomater ; : e34785, 2020 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-33381909

RESUMEN

Fibronectin (FN)-loaded nanofiber scaffolds were developed and assessed concerning their bioactive potential on human apical papilla cells (hAPCs). First, random (NR) and aligned (NA) nanofiber scaffolds of polycaprolactone (PCL) were obtained by electrospinning technique and their biological properties were evaluated. The best formulations of NR and NA were loaded with 0, 5, or 10 µg/ml of FN and their bioactivity was assessed. Finally, FN-loaded NR and NA tubular scaffolds were prepared and their chemotactic potential was analyzed using an in vitro model to mimic the pulp regeneration of teeth with incomplete root formation. All scaffolds tested were cytocompatible. However, NR and NA based on 10% PCL promoted the highest hAPCs proliferation, adhesion and spreading. Polygonal and elongated cells were observed on NR and NA, respectively. The higher the concentration of FN added to the scaffolds, greater cell migration, viability, proliferation, adhesion and spreading, as well as collagen synthesis and gene expression (ITGA5, ITGAV, COL1A1, COL3A1). In addition, tubular scaffolds with NA loaded with FN (10 µg/ml) showed the highest chemotactic potential on hAPCs. It was concluded that FN-loaded NA scaffolds may be an interesting biomaterial to promote hAPCs-mediated pulp regeneration of endodontically compromised teeth with incomplete root formation.

4.
Braz Dent J ; 31(4): 385-391, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32901714

RESUMEN

The present study evaluated the odontogenic potential of human dental pulp cells (HDPCs) exposed to chitosan scaffolds containing calcium aluminate (CHAlCa) associated or not with low doses of simvastatin (SV). Chitosan scaffolds received a suspension of calcium aluminate (AlCa) and were then immersed into solutions containing SV. The following groups were established: chitosan-calcium-aluminate scaffolds (CHAlCa - Control), chitosan calcium-aluminate with 0.5 µM SV (CHAlCa-SV0.5), and chitosan calcium-aluminate with 1.0 µM SV (CHAlCa-SV1.0). The morphology and composition of the scaffolds were evaluated by SEM and EDS, respectively. After 14 days of HDPCs culture on scaffolds, cell viability, adhesion and spread, mineralized matrix deposition as well as gene expression of odontogenic markers were assessed. Calcium aluminate particles were incorporated into the chitosan matrix, which exhibited regular pores homogeneously distributed throughout its structure. The selected SV dosages were biocompatible with HDPCs. Chitosan-calcium-aluminate scaffolds with 1 µM SV induced the odontoblastic phenotype in the HDPCs, which showed enhanced mineralized matrix deposition and up-regulated ALP, Col1A1, and DMP-1 expression. Therefore, one can conclude that the incorporation of calcium aluminate and simvastatin in chitosan scaffolds had a synergistic effect on HDPCs, favoring odontogenic cell differentiation and mineralized matrix deposition.


Asunto(s)
Quitosano , Compuestos de Aluminio , Calcio , Compuestos de Calcio , Humanos , Porosidad , Simvastatina
5.
Braz. dent. j ; 31(4): 385-391, July-Aug. 2020. graf
Artículo en Inglés | LILACS-Express | LILACS, BBO - Odontología | ID: biblio-1132314

RESUMEN

Abstract The present study evaluated the odontogenic potential of human dental pulp cells (HDPCs) exposed to chitosan scaffolds containing calcium aluminate (CHAlCa) associated or not with low doses of simvastatin (SV). Chitosan scaffolds received a suspension of calcium aluminate (AlCa) and were then immersed into solutions containing SV. The following groups were established: chitosan-calcium-aluminate scaffolds (CHAlCa - Control), chitosan calcium-aluminate with 0.5 µM SV (CHAlCa-SV0.5), and chitosan calcium-aluminate with 1.0 µM SV (CHAlCa-SV1.0). The morphology and composition of the scaffolds were evaluated by SEM and EDS, respectively. After 14 days of HDPCs culture on scaffolds, cell viability, adhesion and spread, mineralized matrix deposition as well as gene expression of odontogenic markers were assessed. Calcium aluminate particles were incorporated into the chitosan matrix, which exhibited regular pores homogeneously distributed throughout its structure. The selected SV dosages were biocompatible with HDPCs. Chitosan-calcium-aluminate scaffolds with 1 µM SV induced the odontoblastic phenotype in the HDPCs, which showed enhanced mineralized matrix deposition and up-regulated ALP, Col1A1, and DMP-1 expression. Therefore, one can conclude that the incorporation of calcium aluminate and simvastatin in chitosan scaffolds had a synergistic effect on HDPCs, favoring odontogenic cell differentiation and mineralized matrix deposition.


Resumo O presente estudo avaliou o potencial odontogênico de células da polpa dental humana (HDPCs) em contato com scaffolds de quitosana contendo aluminato de cálcio (CHAlCa) associado ou não à baixas dosagens de sinvastatina (SV). Scaffolds de quitosana receberam uma suspensão de aluminato de cálcio e foram imersos em soluções contendo a droga. Foram estabelecidos três grupos experimentais: scaffolds de quitosana e aluminato de cálcio (CHAlCa - controle), scaffolds de quitosana-aluminato de cálcio com 0.5 µM SV (CHAlCa-SV0.5), e quitosana-aluminato de cálcio com 1.0 µM SV (CHAlCa-SV1.0). A morfologia e composição foram avaliados por MEV e EDS, respectivamente. Após 14 dias do cultivo das HDPCs sobre os scaffolds, foram avaliados a viabilidade celular, adesão e espalhamento, deposição de matriz mineralizada e expressão gênica de marcadores odontogênicos. Observou-se que as partículas de aluminato de cálcio foram incorporadas à matriz de quitosana, a qual exibiu poros regulares distribuídos por toda sua estrutura. As dosagens selecionadas de sinvastatina foram biocompatíveis com as HDPCs. A concentração de 1 µM de SV induziu intensa expressão de fenótipo odontoblástico pelas HDPCs, demonstrando aumento da deposição de matriz mineralizada e maior expressão de ALP, Col1A1 e DMP-1. Portanto, podemos concluir que a incorporação de aluminato de cálcio e sinvastatina em scaffolds de quitosana apresentou um efeito sinérgico nas HDPCs, favorecendo a diferenciação celular e deposição de matriz mineralizada.

6.
Braz Dent J ; 31(3): 304-309, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32667511

RESUMEN

Among other factors, types of bisphosphonates and treatment regimens seem to be strongly associated with the success or failure of installation of osseointegrated implants. This study investigated the influence of two bisphosphonates, sodium alendronate (SA) and zoledronic acid (ZA), on the metabolism of osteoblasts. Human osteoblasts (Saos-2) were seeded onto machined or acid-treated titanium discs previously placed on 24-well plates in complete culture medium. After 24 h, cells were exposed to bisphosphonates at 0.5, 1 or 5 µM for 24 h, 48 h or 7 days. The effects of SA and ZA on osteoblasts were assessed based on the adhesion of these cells to the titanium surfaces by direct fluorescence, cell viability, total protein and collagen synthesis. Alkaline phosphatase activity and mineral nodule deposition by these cells were also evaluated. Data were evaluated by ANOVA and Tukey tests (α=0.05). Decreased adhesion of cells to the titanium discs was observed when exposed to both bisphosphonates; however, this lack of cell adhesion was more evident for ZA-treated cells. In addition, the exposure of osteoblasts to ZA decreased the viability, ALP activity and mineral nodule deposition, which may be related to poor osseointegration after implant installation.


Asunto(s)
Difosfonatos , Titanio , Fosfatasa Alcalina , Adhesión Celular , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Humanos , Osteoblastos , Propiedades de Superficie , Ácido Zoledrónico
7.
Nanomaterials (Basel) ; 10(7)2020 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-32707741

RESUMEN

Resin-modified glass ionomer cement (RMGIC) has important properties. However, like other restorative materials, it has limitations such as decreased biocompatibility. The incorporation of nanoparticles (NP) in the RMGIC resulted in improvements in some of its properties. The aim of this study was to evaluate the physical-biological properties of RMGIC with the addition of nanohydroxyapatite (HANP). MATERIAL AND METHODS: Vitremer RMGIC was used, incorporating HANP by amalgamator, vortex and manual techniques, totaling ten experimental groups. The distribution and dispersion of the HANP were evaluated qualitatively by field emission scanning electron microscope (SEM-FEG). The evaluation of image porosity (SEM-FEG) with the help of imageJ. Cell viability 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl tetrazoline bromide (MTT) and cell morphology analyses were performed on MDPC-23 odontoblastoid cells at 24 and 72 h. RESULTS: It was possible to observe good dispersion and distribution of HANP in the samples in all experimental groups. The incorporation of 5% HANP into the vortex stirred RMGIC resulted in fewer pores. The increase in the concentration of HANP was directly proportional to the decrease in cytotoxicity. CONCLUSIONS: It is concluded that the use of a vortex with the incorporation of 5% HANP is the most appropriate mixing technique when considering the smallest number of pores inside the material. A higher concentration of HANP resulted in better cell viability, suggesting that this association is promising for future studies of new restorative materials.

8.
Braz. dent. j ; 31(3): 304-309, May-June 2020. graf
Artículo en Inglés | LILACS-Express | LILACS, BBO - Odontología | ID: biblio-1132294

RESUMEN

Abstract Among other factors, types of bisphosphonates and treatment regimens seem to be strongly associated with the success or failure of installation of osseointegrated implants. This study investigated the influence of two bisphosphonates, sodium alendronate (SA) and zoledronic acid (ZA), on the metabolism of osteoblasts. Human osteoblasts (Saos-2) were seeded onto machined or acid-treated titanium discs previously placed on 24-well plates in complete culture medium. After 24 h, cells were exposed to bisphosphonates at 0.5, 1 or 5 µM for 24 h, 48 h or 7 days. The effects of SA and ZA on osteoblasts were assessed based on the adhesion of these cells to the titanium surfaces by direct fluorescence, cell viability, total protein and collagen synthesis. Alkaline phosphatase activity and mineral nodule deposition by these cells were also evaluated. Data were evaluated by ANOVA and Tukey tests (α=0.05). Decreased adhesion of cells to the titanium discs was observed when exposed to both bisphosphonates; however, this lack of cell adhesion was more evident for ZA-treated cells. In addition, the exposure of osteoblasts to ZA decreased the viability, ALP activity and mineral nodule deposition, which may be related to poor osseointegration after implant installation.


Resumo Entre outros fatores, os tipos de bisfosfonatos bem como os regimes de tratamento parecem estar diretamente associados com o sucesso ou falhas na instalação de implantes osseointegrados. Este estudo avaliou a influência de dois bisfosfonatos, o alendronato de sódio (AS) e o ácido zoledrônico (AZ), no metabolismo de osteoblastos. Osteoblastos humanos (Saos-2) foram cultivados sobre discos de titânio polidos ou submetidos a tratamento ácido superficial, previamente alocados em placas de 24 compartimentos, utilizando meio de cultura completo. Após 24 horas, as células foram expostas aos bisfosfonatos, nas concentrações de 0,5, 1 ou 5 µM, por 24 h, 48 h, ou 7 dias. Os efeitos do AZ e AZ sobre os osteoblastos foram determinados considerando a adesão destas células às superfícies de titânio, por meio de fluorescência direta, a viabilidade celular, produção de proteína total e síntese de colágeno. A atividade de fosfatase alcalina e a deposição de nódulos mineralizados também foram avaliadas. Os dados foram analisados por meio do teste ANOVA complementado por Tukey (α = 0.05). Menor adesão dos osteoblastos foi observada quando estas células foram expostas a ambos os bisfosfonatos, porém, esta falha na adesão foi mais evidente para as células tratadas com AZ. Além disso, a exposição dos osteoblastos ao AZ também resultou em diminuição da viabilidade, atividade de ALP e deposição de nódulos mineralizados, o que pode estar relacionado a uma pobre osseointegração após a instalação do implante.

9.
J Prosthet Dent ; 124(1): 122.e1-122.e9, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32220399

RESUMEN

STATEMENT OF PROBLEM: If the components in the acrylic resins used to fabricate interim crows are cytotoxic, they can interfere with the integrity of the adjacent periodontal tissue and the dentin-pulp complex. PURPOSE: The purpose of this in vitro study was to assess the cytotoxicity of resin-based materials used to prepare interim crowns. MATERIAL AND METHODS: The following materials were used in this study: CAR, conventional acrylic resin powder and liquid; BR, bis-acrylic resin; and PAR, pressed acrylic resin of the CAD-CAM type. Glass disks were used as the control (Co). Oral epithelial cells (NOK) were seeded on glass disks and standardized disks prepared with the resins under study. After incubation for 24 hours, the cells were analyzed for viability (Alamar Blue and Live or Dead), adhesion, and morphology (SEM and fluorescence), as well as epidermal growth factor synthesis (EGF-ELISA). The surface roughness (Ra) of test specimens was evaluated under a confocal microscope. The data were submitted to ANOVA and the Tukey HSD statistical tests (α=.05). RESULTS: The highest Ra value was observed in BR in comparison with CAR, PAR, and Co (P<.05). The highest viability, adhesion, and EGF synthesis values were determined for the cells in contact with PAR (P<.001). CONCLUSIONS: The computer-aided design and computer-aided manufacturing (CAD-CAM)-type resin favored adhesion, metabolism, and epithelial cell proliferation, and it was therefore considered cytocompatible.


Asunto(s)
Resinas Acrílicas , Coronas , Resinas Compuestas , Diseño Asistido por Computadora , Materiales Dentales , Ensayo de Materiales , Propiedades de Superficie
10.
J Biomed Mater Res B Appl Biomater ; 108(6): 2546-2559, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32061059

RESUMEN

The aim of this study was to develop a highly porous calcium-containing chitosan scaffold suitable for dentin regeneration. A calcium hydroxide (Ca[OH]2 ) suspension was used to modulate the degree of porosity and chemical composition of chitosan scaffolds. The chitosan solution concentration and freezing protocol were adjusted to optimize the porous architecture using the phase-separation technique. Scanning electron microscopy/energy-dispersive spectroscopy demonstrated the fabrication of a highly porous calcium-linked chitosan scaffold (CH-Ca), with a well-organized and interconnected porous network. Scaffolds were cross-linked on glutaraldehyde (GA) vapor. Following a 28-day incubation in water, cross-linked CH scaffold had no changes on humid mass, and CH-Ca featured a controlled degradability profile since the significant humid mass loss was observed only after 21 (26.0%) and 28 days (42.2%). Fourier-transform infrared spectroscopy indicated the establishment of Schiff base on cross-linked scaffolds, along with calcium complexation for CH-Ca. Cross-linked CH-Ca scaffold featured a sustained Ca2+ release up to 21 days in a humid environment. This porous and stable architecture allowed for human dental pulp cells (HDPCs) to spread throughout the scaffold, with cells exhibiting a widely stretched cytoplasm; whereas, the cells seeded onto CH scaffold were organized in clusters. HDPCs seeded onto CH-Ca featured significantly higher ALP activity, and gene expressions for ALP, Col1, DMP-1, and DSPP in comparison to CH, leading to a significant 3.5 times increase in calcium-rich matrix deposition. In sum, our findings suggest that CH-Ca scaffolds are attractive candidates for creating a highly porous and bioactive substrate for dentin tissue engineering.

11.
Lasers Med Sci ; 35(5): 1205-1212, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32030556

RESUMEN

The aim of this study was to assess the effects of IL-6 and IL-8 cytokines on human gingival fibroblasts (HGF) cultured in a 3-D model and the possible photobiomodulation (PBM) of such effects by low-level laser therapy. In complete culture medium (DMEM), HGF from a healthy patient were seeded in a type I collagen matrix inserted into 24-well plates. After 5 days of incubation, the cytokines were added or not to serum-free DMEM, which was applied to the cell-enriched matrices. Then, PBM was performed: three consecutive irradiations using LaserTable diode device (780 nm, 0.025 W) at 0.5 J/cm2 were delivered or not to the cells. Twenty-four hours after the last irradiation, cell viability and morphology, gene expression, and synthesis of inflammatory cytokines and growth factors were assessed. The histological evaluation demonstrated that, for all groups, matrices presented homogeneous distribution of cells with elongated morphology. However, numerous cytokine-exposed cells were rounded. IL-6 and IL-8 decreased cell viability, synthesis of VEGF, and gene expression of collagen type I. PBM enhanced cell density in the matrices and stimulated VEGF expression, even after IL-6 challenge. Reduced TNF-α synthesis occurred in those cells subjected to PBM. In conclusion, PBM can penetrate collagen matrix and stimulate HGF, highlighting the relevance of this research model for further phototherapy studies and in vitro biomodulation of the healing process.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Citocinas/metabolismo , Fibroblastos/patología , Fibroblastos/efectos de la radiación , Encía/patología , Inflamación/patología , Terapia por Luz de Baja Intensidad , Modelos Biológicos , Supervivencia Celular/efectos de la radiación , Colágeno Tipo I/metabolismo , Regulación de la Expresión Génica/efectos de la radiación , Humanos , Interleucina-1beta/biosíntesis , Factor de Necrosis Tumoral alfa/biosíntesis , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Cicatrización de Heridas/efectos de la radiación
12.
Int J Paediatr Dent ; 30(5): 650-659, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32077547

RESUMEN

BACKGROUND: Primary and permanent teeth composition may influence dissolution and degradation rates. AIM: To compare the dissolution and degradation of primary and permanent teeth. DESIGN: Enamel and dentin powders were obtained from primary molars and premolars and incubated within different pH buffers. Calcium and inorganic phosphate release was quantified in the buffers by atomic absorption and light spectrophotometry. A colorimetric assay was used to assess the MMP activity of primary dentin (PrD) and permanent dentin (PeD). Collagen degradation was assessed by dry mass loss, change in elastic modulus (E), and ICTP and CTX release. Data were submitted to ANOVA and Tukey's tests (α = 0.05). RESULTS: Similar dissolution was found between PrD and PeD after 256 hours. At pH 4.5, enamel released more minerals than dentin whereas at pH 5.5 the inverse result was observed. MMP activity was similar for both substrates. PrD showed higher dry mass loss after 1 week. In general, greater reduction in E was recorded for PrD. Higher quantities of ICTP and CTX were released from PrD after 1 week. CONCLUSIONS: Primary and permanent teeth presented similar demineralization rates. Collagen degradation, however, was faster and more substantial for PrD.


Asunto(s)
Dentina , Metaloproteinasas de la Matriz , Dentición Permanente , Diente Molar , Solubilidad
13.
Clin Oral Investig ; 24(5): 1739-1748, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31372829

RESUMEN

OBJECTIVES: This study assessed the human pulp response after adhesive restoration of cavities by indirect pulp capping with a conventional or a resin-modified glass ionomer cement. MATERIALS AND METHODS: Deep cavities prepared in 26 human premolars were lined with Riva Light Cure (Riva LC), Riva Self Cure (Riva SC), or Dycal, and then restored with composite resin. Four teeth were used as intact control. After time intervals of 7 or 30 days, the teeth were extracted, processed for histological evaluation of the pulp, and the remaining dentin thickness (RDT) between the cavity floor and the pulp was measured. RESULTS: At 7 days, a slight pulp inflammation associated with discrete tissue disorganization was observed in most of t the teeth lined with Riva LC and Riva SC. Moderate pulp inflammation occurred in one tooth lined with Riva LC. Bacteria were identified in one specimen of the same group that exhibited no pulp damage. At 30 days, slight pulp inflammation and discrete tissue disorganization persisted in two specimens treated with Riva LC, in which a thin layer of tertiary dentin was deposited. Mean RDTs ranged from 383.0 to 447.8 µm. CONCLUSIONS: Riva LC produced more damage to the pulp than Riva SC. However, the initial pulp damage decreased over time and after 30 days both GICs were labeled as biocompatible. CLINICAL RELEVANCE: In this study conducted with human teeth, the conventional and the resin-modified glass ionomer cements investigated were shown not to cause post-operative sensitivity or persistent pulp damage when applied as liners in very deep cavities, thereby indicating their biocompatibility.


Asunto(s)
Caries Dental/terapia , Pulpa Dental/efectos de los fármacos , Restauración Dental Permanente , Dentina Secundaria , Cementos de Ionómero Vitreo , Hidróxido de Calcio , Resinas Compuestas , Dentina , Humanos , Inflamación , Minerales , Cementos de Resina
14.
Clin Oral Investig ; 24(2): 663-674, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31119382

RESUMEN

OBJECTIVES: This study aimed to develop a porous chitosan-calcium-aluminate scaffold (CH-AlCa) in combination with a bioactive dosage of 1α,25-dihydroxyvitamin D3 (1α,25VD), to be used as a bioactive substrate capable to increase the odontogenic potential of human dental pulp cells (HDPCs). MATERIALS AND METHODS: The porous CH-AlCa was developed by the incorporation of an AlCa suspension into a CH solution under vigorous agitation, followed by phase separation at low temperature. Scaffold architecture, porosity, and calcium release were evaluated. Thereafter, the synergistic potential of CH-AlCa and 1 nM 1α,25VD, selected by a dose-response assay, for HDPCs seeded onto the materials was assessed. RESULTS: The CH-AlCa featured an organized and interconnected pore network, with increased porosity in comparison with that of plain chitosan scaffolds (CH). Increased odontoblastic phenotype expression on the human dental pulp cell (HDPC)/CH and HDPC/CH-AlCa constructs in the presence of 1 nM 1α,25VD was detected, since alkaline phosphatase activity, mineralized matrix deposition, dentin sialophosphoprotein/dentin matrix acidic phosphoprotein 1 mRNA expression, and cell migration were overstimulated. This drug featured a synergistic effect with CH-AlCa, since the highest values of cell migration and odontoblastic markers expression were observed in this experimental condition. CONCLUSIONS: The experimental CH-AlCa scaffold increases the chemotaxis and regenerative potential of HDPCs, and the addition of low-dosage 1α,25VD to this scaffold enhances the potential of these cells to express an odontoblastic phenotype. CLINICAL RELEVANCE: Chitosan scaffolds enriched with calcium-aluminate in association with low dosages of 1α,25-dihydroxyvitamin D3 provide a highly bioactive microenvironment for dental pulp cells prone to dentin regeneration, thus providing potential as a cell-free tissue engineering system for direct pulp capping.


Asunto(s)
Pulpa Dental , Calcio , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Quitosano , Humanos , Odontoblastos , Andamios del Tejido
15.
J Appl Oral Sci ; 27: e20180453, 2019 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-31411261

RESUMEN

OBJECTIVE: This study was designed for the chemical activation of a 35% hydrogen peroxide (H2O2) bleaching gel to increase its whitening effectiveness and reduce its toxicity. METHODOLOGY: First, the bleaching gel - associated or not with ferrous sulfate (FS), manganese chloride (MC), peroxidase (PR), or catalase (CT) - was applied (3x 15 min) to enamel/dentin discs adapted to artificial pulp chambers. Then, odontoblast-like MDPC-23 cells were exposed for 1 h to the extracts (culture medium + components released from the product), for the assessment of viability (MTT assay) and oxidative stress (H2DCFDA). Residual H2O2 and bleaching effectiveness (DE) were also evaluated. Data were analyzed with one-way ANOVA complemented with Tukey's test (n=8. p<0.05). RESULTS: All chemically activated groups minimized MDPC-23 oxidative stress generation; however, significantly higher cell viability was detected for MC, PR, and CT than for plain 35% H2O2 gel. Nevertheless, FS, MC, PR, and CT reduced the amount of residual H2O2 and increased bleaching effectiveness. CONCLUSION: Chemical activation of 35% H2O2 gel with MC, PR, and CT minimized residual H2O2 and pulp cell toxicity; but PR duplicated the whitening potential of the bleaching gel after a single 45-minute session.


Asunto(s)
Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/toxicidad , Blanqueadores Dentales/química , Blanqueadores Dentales/toxicidad , Blanqueamiento de Dientes/métodos , Análisis de Varianza , Catalasa/química , Supervivencia Celular , Células Cultivadas , Cloruros/química , Color , Pulpa Dental/química , Pulpa Dental/diagnóstico por imagen , Dentina/química , Dentina/efectos de los fármacos , Compuestos Ferrosos/química , Compuestos de Manganeso/química , Odontoblastos/efectos de los fármacos , Peroxidasa/química , Valores de Referencia , Reproducibilidad de los Resultados , Estadísticas no Paramétricas , Factores de Tiempo
16.
Arch Oral Biol ; 102: 48-54, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30965181

RESUMEN

OBJECTIVES: Different strategies, such as modifications on the implant abutments surface have been proposed to accelerate and improve the formation of the biological seal (BS). The aim of this study was to characterize a titanium (Ti) surface impregnated with epidermal growth factor (EGF) and to assess its influence on the metabolism and adhesion of oral mucosal cells. DESIGN: Ti discs were coated with EGF (100 nM) conjugated with a fluorophore and analyzed by fluorescence microscopy. The surface roughness analysis (Ra) of the EGF-coated Ti was performed by confocal microscopy. The EGF released in the wet environment was determined at 0, 24, 48 and 72 h by fluorimetric quantification. For assessment of the biological effects of EGF-coated Ti, gingival fibroblasts were seeded (5 × 104 cells) onto the substrate coated or not with this growth factor. After 24 h, cell adhesion and viability were evaluated by ANOVA and Tukey tests, α = .05. RESULTS: Immediate release of EGF as well as its incorporation by fibroblasts within 1 h after cells were seeded was observed. EGF-coated Ti discs presented significantly enhance surface roughness. Increased cell viability was observed on the EGF-coated discs. CONCLUSION: EGF applied to Ti discs stimulated the adhesion and metabolism of gingival fibroblasts and could be considered as an interesting alternative for improving the BS.


Asunto(s)
Encía , Adhesión Celular , Células Cultivadas , Factor de Crecimiento Epidérmico , Fibroblastos , Humanos , Propiedades de Superficie , Titanio
17.
J Mech Behav Biomed Mater ; 91: 220-228, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30597375

RESUMEN

OBJECTIVE: The purpose of this study was to evaluate the effect of Er:YAG laser for selective removal of carious lesion, followed by biomodification with chitosan on the microtensile bond strength (µTBS), adhesive interface, dry mass loss and hydroxyproline release (HYP). METHODS: Artificial lesions were created in 104 bovine dentin blocks. Blocks were divided according to caries removal method: bur or Er:YAG laser. Seventy-six blocks were acid etched and subdivided according to dentin biomodification: no chitosan and 2.5% chitosan. Composite resin restorations were performed. Blocks were sectioned into beams and stored in water. After 24 h, 6 and 12 months, beams were submitted to µTBS test (n = 10) and analysis of adhesive interface by SEM (n = 3). The other 28 blocks were sectioned into beams and initial dry mass (DM) was determined (n = 7). Beams were stored and after 7 days, DM was redetermined. HYP release (n = 7) was evaluated by ELISA. Data were analyzed by ANOVA and Bonferroni's tests (α = 0.05). RESULTS: After 24 h, the highest µTBS was found for bur (p < 0.001). After 6 months, methods were similar (p = 0.432). After 12 months, laser-irradiated dentin showed the highest µTBS values (p = 0.025). Chitosan promoted higher µTBS values after 6 (p = 0.011) and 12 months (p < 0.001) preserving adhesive interface. Dry mass loss and HYP release were not influenced (p > 0.05) by caries removal method or by dentin biomodification. CONCLUSION: The bond strength to demineralized dentin reduced over 50% in all groups after water storage. From 6 months of water storage, Er:YAG laser irradiation and biomodification with chitosan maintained the stability of the resin-dentin bonds, but did not influence dry mass loss and HYP release.


Asunto(s)
Quitosano/química , Dentina/química , Láseres de Estado Sólido , Minerales/química , Cementos de Resina/química , Animales , Bovinos , Resistencia a la Tracción
18.
Clin Oral Investig ; 23(9): 3457-3469, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30552591

RESUMEN

OBJECTIVES: To assess the biological, antimicrobial, and mechanical effects of the treatment of deep dentin with simvastatin (SV) before application of a glass-ionomer cement (GIC). MATERIALS AND METHODS: Dentin discs were adapted to artificial pulp chambers and SV (2.5 or 1.0 mg/mL) was applied to the occlusal surface, either previously conditioned or not with EDTA (±EDTA). The extracts (culture medium + SV that diffused through dentin) was obtained and then applied to cultured odontoblast-like MDPC-23 cells. Cell viability, alkaline phosphatase (ALP) activity, and mineralization nodule (MN) deposition were evaluated. Untreated discs were used as control. The antibacterial activity of SV (2.5 or 1.0 mg/mL) against Streptococcus mutans and Lactobacillus acidophilus, as well as the bond strength of GIC to dentin in the presence of SV 2.5 mg/mL (±EDTA) were also assessed. The data were analyzed by ANOVA/Tukey tests (α = 5%). RESULTS: EDTA + SV 2.5 mg/mL significantly enhanced the ALP activity and MN deposition in comparison with the control, without changing in the cell viability (p < 0.05). The association EDTA + SV 2.5 mg/mL + GIC determined the highest ALP and MN values (p < 0.05). SV presented intense antimicrobial activity, and the EDTA dentin conditioning followed by SV application increased bond strength values compared with SV treatment alone (p < 0.05). CONCLUSION: SV presents antimicrobial activity and diffuses across conditioned dentin to biostimulate odontoblast-like pulp cells. CLINICAL SIGNIFICANCE: The use of SV as adjuvant agent for indirect pulp capping may biostimulate pulp cells thus preserving vitality and function of the pulp-dentin complex.


Asunto(s)
Recubrimiento de la Cavidad Dental , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Simvastatina , Dentina/efectos de los fármacos , Dentina/microbiología , Cementos de Ionómero Vitreo , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Odontoblastos , Simvastatina/uso terapéutico
19.
J. appl. oral sci ; 27: e20180453, 2019. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1012522

RESUMEN

Abstract Objective This study was designed for the chemical activation of a 35% hydrogen peroxide (H2O2) bleaching gel to increase its whitening effectiveness and reduce its toxicity. Methodology First, the bleaching gel - associated or not with ferrous sulfate (FS), manganese chloride (MC), peroxidase (PR), or catalase (CT) - was applied (3x 15 min) to enamel/dentin discs adapted to artificial pulp chambers. Then, odontoblast-like MDPC-23 cells were exposed for 1 h to the extracts (culture medium + components released from the product), for the assessment of viability (MTT assay) and oxidative stress (H2DCFDA). Residual H2O2 and bleaching effectiveness (DE) were also evaluated. Data were analyzed with one-way ANOVA complemented with Tukey's test (n=8. p<0.05). Results All chemically activated groups minimized MDPC-23 oxidative stress generation; however, significantly higher cell viability was detected for MC, PR, and CT than for plain 35% H2O2 gel. Nevertheless, FS, MC, PR, and CT reduced the amount of residual H2O2 and increased bleaching effectiveness. Conclusion Chemical activation of 35% H2O2 gel with MC, PR, and CT minimized residual H2O2 and pulp cell toxicity; but PR duplicated the whitening potential of the bleaching gel after a single 45-minute session.

20.
J Mater Sci Mater Med ; 29(6): 88, 2018 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-29904797

RESUMEN

The restoration of dentine-pulp complex remains a challenge for dentists; nonetheless, it has been poorly addressed. An ideal system should modulate the host response, as well as enable the recruitment, proliferation and differentiation of relevant progenitor cells. Herein was proposed a photocrosslinkable hydrogel system based on hyaluronic acid (HA) and platelet lysate (PL). PL is a cocktail of growth factors (GFs) and cytokines involved in wound healing orchestration, obtained by the cryogenic processing of platelet concentrates, and was expected to provide the HA hydrogels specific biochemical cues to enhance pulp cells' recruitment, proliferation and differentiation. Stable HA hydrogels incorporating PL (HAPL) were prepared after photocrosslinking of methacrylated HA (Met-HA) previously dissolved in PL, triggered by the Ultra Violet activated photoinitiator Irgacure 2959. Both the HAPL and plain HA hydrogels were shown to be able to recruit cells from a cell monolayer of human dental pulp stem cells (hDPSCs) isolated from permanent teeth. The hDPCs were also seeded directly over the hydrogels (5 × 104 cells/hydrogel) and cultured in osteogenic conditions. Cell metabolism and DNA quantification were higher, in all time-points, for PL supplemented hydrogels (p < 0,05). Alkaline phosphatase (ALPL) activity and calcium quantification peaks were observed for the HAPL group at 21 days (p < 0,05). The gene expression for ALPL and COLIA1 was up-regulated at 21 days to HAPL, compared with HA group (p < 0,05). Within the same time point, the gene expression for RUNX2 did not differ between the groups. Overall, data demonstrated that the HA hydrogels incorporating PL increased the cellular metabolism and stimulate the mineralized matrix deposition by hDPSCs, providing clear evidence of the potential of the proposed system for the repair of damaged pulp/dentin tissue and endodontics regeneration.


Asunto(s)
Plaquetas/citología , Ácido Hialurónico/química , Hidrogeles/química , Células Madre/citología , Fosfatasa Alcalina/metabolismo , Calcio/química , Diferenciación Celular , Proliferación Celular , Quimiotaxis , Reactivos de Enlaces Cruzados/química , Pulpa Dental/citología , Citometría de Flujo , Perfilación de la Expresión Génica , Humanos , Osteogénesis , Fotoquímica , Regeneración , Ingeniería de Tejidos , Diente/citología
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