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OBJECTIVES: To synthesize casein enzymatic hydrolysate (CEH)-laden gelatin methacryloyl (GelMA) fibrous scaffolds and evaluate the cytocompatibility and anti-inflammatory effects on dental pulp stem cells (DPSCs). MATERIALS AND METHODS: GelMA fibrous scaffolds with 10%, 20%, and 30% CEH (w/w) and without CEH (control) were obtained via electrospinning. Chemo-morphological, degradation, and mechanical analyses were conducted to evaluate the morphology and composition of the fibers, mass loss, and mechanical properties, respectively. Adhesion/spreading and viability of DPSCs seeded on the scaffolds were also assessed. The anti-inflammatory potential on DPSCs was tested after the chronic challenge of cells with lipopolysaccharides (LPS), followed by treatment with extracts obtained after immersing the scaffolds in α-MEM. The synthesis of the pro-inflammatory cytokines IL-6, IL-1α, and TNF-α was measured by ELISA. Data were analyzed by ANOVA/post-hoc tests (α = 5%). RESULTS: CEH-laden electrospun fibers had a larger diameter than pure GelMA (p ≤ 0.036). GelMA scaffolds laden with 20% and 30% CEH had a greater mass loss. Tensile strength was reduced for the 10% CEH fibers (p = 0.0052), whereas no difference was observed for the 20% and 30% fibers (p ≥ 0.6736) compared to the control. Young's modulus decreased with CEH (p < 0.0001). Elongation at break increased for the 20% and 30% CEH scaffolds (p ≤ 0.0038). Over time, DPSCs viability increased across all groups, indicating cytocompatibility, with CEH-laden scaffolds exhibiting greater cell viability after seven days (p ≤ 0.0166). Also, 10% CEH-GelMA scaffolds decreased the IL-6, IL-1α, and TNF-α synthesis (p ≤ 0.035). CONCLUSION: CEH-laden GelMA scaffolds facilitated both adhesion and proliferation of DPSCs, and 10% CEH provided anti-inflammatory potential after chronic LPS challenge. CLINICAL RELEVANCE: CEH incorporated in GelMA fibrous scaffolds demonstrated the potential to be used as a cytocompatible and anti-inflammatory biomaterial for vital pulp therapy.
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Anti-Inflamatórios , Caseínas , Sobrevivência Celular , Polpa Dentária , Gelatina , Alicerces Teciduais , Gelatina/química , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Alicerces Teciduais/química , Humanos , Anti-Inflamatórios/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Metacrilatos/química , Teste de Materiais , Ensaio de Imunoadsorção Enzimática , Resistência à Tração , Células Cultivadas , Células-Tronco/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Citocinas/metabolismo , Propriedades de SuperfícieRESUMO
OBJECTIVES: To investigate the transdentinal effects of surface reaction-type pre-reacted glass-ionomer (S-PRG) fillers on odontoblast-like cells. METHODS: An eluate of S-PRG fillers was obtained by dissolving the particles in distilled water (1:1 m/v). Dentin discs with similar permeability were mounted into artificial pulp chambers and MDPC-23 cells were seeded on their pulpal surface. The occlusal surface was treated with (n = 10): ultrapure water (negative control - NC), hydrogen peroxide (positive control - PC), S-PRG eluate exposure for 1 min (S-PRG 1 min), or S-PRG filler eluate exposure for 30 min (S-PRG 30 min). After 24 h, cell viability (alamarBlue) and morphology (SEM) were evaluated. The extract obtained from transdentinal diffusion was applied to MDPC-23 pre-cultured in plates for another 24 h to evaluate viability (alamarBlue, 1, 3, and 7 days), gene expression of Col1a1, Alpl, Dspp, and Dmp1 (RT-qPCR, 1 and 7 days), and mineralization (Alizarin Red, 7 days). Data were analyzed with ANOVA (α = 5 %). RESULTS: While S-PRG 1 min did not differ from NC, S-PRG 30 min reduced 17.9 % viability of cells from discs. S-PRG treatments resulted in low cell detaching from dentin, and the remaining cells exhibited typical morphology or minor cytoplasmic contraction. S-PRG 30 min slightly increased cell viability (6 %) 1 day after contact with the extract. S-PRG treatments upregulated the expression of the investigated genes, especially after 1 day. S-PRG 30 min stimulated mineralization activity by 39.7 %. CONCLUSIONS: S-PRG filler eluate does not cause transdentinal cytotoxicity on odontoblast-like cells, and long-term exposure can stimulate their dentinogenic-related mineralization activity. SIGNIFICANCE: The transdentinal elution of ions from S-PRG fillers is not expected to be harmful to the dental pulp and may exert bioactive effects by inducing dentin matrix deposition through the metabolism of underlying odontoblasts.
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Sobrevivência Celular , Dentina , Odontoblastos , Odontoblastos/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dentina/efeitos dos fármacos , Cimentos de Ionômeros de Vidro/farmacologia , Cimentos de Ionômeros de Vidro/química , Cimentos de Ionômeros de Vidro/toxicidade , Animais , Microscopia Eletrônica de Varredura , Teste de Materiais , Propriedades de Superfície , Camundongos , Células Cultivadas , Expressão Gênica/efeitos dos fármacos , Resinas Acrílicas , Dióxido de SilícioRESUMO
This study investigated the incorporation of sources of calcium, phosphate, or both into electrospun scaffolds and evaluated their bioactivity on human dental pulp cells (HDPCs). Additionally, scaffolds incorporated with calcium hydroxide (CH) were characterized for degradation, calcium release, and odontogenic differentiation by HDPCs. Polycaprolactone (PCL) was electrospun with or without 0.5% w/v of calcium hydroxide (PCL + CH), nano-hydroxyapatite (PCL + nHA), or ß-glycerophosphate (PCL + ßGP). SEM/EDS analysis confirmed fibrillar morphology and particle incorporation. HDPCs were cultured on the scaffolds to assess cell viability, adhesion, spreading, and mineralized matrix formation. PCL + CH was also evaluated for gene expression of odontogenic markers (RT-qPCR). Data were submitted to ANOVA and Student's t-test (α = 5%). Added CH increased fiber diameter and interfibrillar spacing, whereas ßGP decreased both. PCL + CH and PCL + nHA improved HDPC viability, adhesion, and proliferation. Mineralization was increased eightfold with PCL + CH. Scaffolds containing CH gradually degraded over six months, with calcium release within the first 140 days. CH incorporation upregulated DSPP and DMP1 expression after 7 and 14 days. In conclusion, CH- and nHA-laden PCL fiber scaffolds were cytocompatible and promoted HDPC adhesion, proliferation, and mineralized matrix deposition. PCL + CH scaffolds exhibit a slow degradation profile, providing sustained calcium release and stimulating HDPCs to upregulate odontogenesis marker genes.
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OBJECTIVE: To evaluate whether coating enamel with a polymeric primer (PPol) containing titanium tetrafluoride (TiF4) before applying a bleaching gel with 35% H2O2 (35% BG) increases esthetic efficacy, prevents changes in morphology and hardness of enamel, as well as reduces the cytotoxicity from conventional in-office bleaching. MATERIALS AND METHODS: Standardized enamel/dentin discs were stained and bleached for 45 min (one session) with 35% BG. Groups 2TiF4, 6TiF4, and 10TiF4 received the gel on the enamel previously coated with PPol containing 2 mg/mL, 6 mg/mL, or 10 mg/mL, respectively. No treatment or application of 35% BG directly on enamel were used as negative control (NC), and positive control (PC), respectively. UV-reflectance spectrophotometry (CIE L*a*b* system, ΔE00, and ΔWI, n = 8) determined the bleaching efficacy of treatments. Enamel microhardness (Knoop, n = 8), morphology, and composition (SEM/EDS, n = 4) were also evaluated. Enamel/dentin discs adapted to artificial pulp chambers (n = 8) were used for trans-amelodentinal cytotoxicity tests. Following the treatments, the extracts (culture medium + bleaching gel components diffused through the discs) were collected and applied to odontoblast-like MDPC-23 cells, which were assessed concerning their viability (alamarBlue, n = 8; Live/Dead, n = 4), oxidative stress (n = 8), and morphology (SEM). The amount of H2O2 in the extracts was also determined (leuco crystal violet/peroxidase, n = 8). The numerical data underwent one-criterion variance analysis (one-way ANOVA), followed by Tukey's test, at a 5% significance level. RESULTS: Regarding the ΔE00, no difference was observed among groups 2TiF4, 6TiF4, and PC (p > 0.05). The ΔWI was similar between groups 2TiF4 and PC (p > 0.05). The ΔWI of group 6TiF4 was superior to PC (p < 0.05), and group 10TiF4 achieved the highest ΔE00 and ΔWI values (p < 0.05). Besides limiting enamel microstructural changes compared to PC, group 10TiF4 significantly increased the hardness of this mineralized dental tissue. The highest cellular viability occurred in 10TiF4 compared to the other bleached groups (p < 0.05). Trans-amelodentinal H2O2 diffusion decreased in groups 2TiF4, 6TiF4, and 10TiF4 in comparison with PC (p < 0.05). CONCLUSION: Coating enamel with a PPol containing TiF4 before applying a 35% BG may increase enamel microhardness and esthetic efficacy and reduce the trans-amelodentinal cytotoxicity of conventional in-office tooth bleaching. The PPol containing 10 mg/mL of TiF4 promoted the best outcomes.
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Clareadores Dentários , Clareamento Dental , Peróxido de Hidrogênio/química , Clareadores Dentários/farmacologia , Dentina , Clareamento Dental/efeitos adversos , Esmalte DentárioRESUMO
In vitro models of the dental pulp microenvironment have been proposed for the assessment of biomaterials, to minimise animal use in operative dentistry. In this study, a scaffold/3-D dental pulp cell culture interface was created in a microchip, under simulated dental pulp pressure, to evaluate the cell-homing potential of a chitosan (CH) scaffold functionalised with calcium aluminate (the 'CHAlCa scaffold'). This microphysiological platform was cultured at a pressure of 15 cm H2O for up to 14 days; cell viability, migration and odontoblastic differentiation were then assessed. The CHAlCa scaffold exhibited intense chemotactic potential, causing cells to migrate from the 3-D culture to its surface, followed by infiltration into the macroporous structure of the scaffold. By contrast, the cells in the presence of the non-functionalised chitosan scaffold showed low cell migration and no cell infiltration. CHAlCa scaffold bioactivity was confirmed in dentin sialophosphoprotein-positive migrating cells, and odontoblastic markers were upregulated in 3-D culture. Finally, in situ mineralised matrix deposition by the cells was confirmed in an Alizarin Red-based assay, in which the CHAlCa and CH scaffolds were adapted to fit within dentin discs. More intense deposition of matrix was observed with the CHAlCa scaffold, as compared to the CH scaffold. In summary, we present an in vitro platform that provides a simple and reproducible model for selecting and developing innovative biomaterials through the assessment of their cell-homing potential. By using this platform, it was shown that the combination of calcium aluminate and chitosan has potential as an inductive biomaterial that can mediate dentin tissue regeneration during cell-homing therapies.
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Compostos de Alumínio , Compostos de Cálcio , Quitosana , Animais , Alicerces Teciduais/química , Polpa Dentária , Materiais Biocompatíveis/química , Diferenciação Celular , Células Cultivadas , Engenharia TecidualRESUMO
This in vitro experimental investigation aimed to evaluate the impact of the combined application of a nanofiber scaffold (NS), a polymeric catalyst primer (PCP) containing 10 mg/mL of heme peroxidase enzyme, and violet LED (LEDv) on the esthetic efficacy (EE), trans-amelodentinal cytotoxicity (TC), and procedural duration of conventional in-office bleaching therapy. To achieve this, 96 standardized enamel/dentin discs were individually placed in artificial pulp chambers. A 35% hydrogen peroxide (H2O2) bleaching gel was administered for 45, 30, or 15 min to the enamel, either previously coated with NS + PCP or left uncoated, followed by irradiation with LEDv for 15 min or no irradiation. The established groups were as follows: G1, negative control (no treatment); G2, 35% H2O2/45 min; G3, NS + PCP + LEDv; G4, NS + PCP + 35%H2O2/45 min + LEDv; G5, NS + PCP + 35%H2O2/30 min + LEDv; and G6, NS + PCP + 35%H2O2/15 min + LEDv. Extracts (culture medium + gel components diffused through the discs) were collected and applied to odontoblast-like MDPC-23 cells. EE (ΔE00 and ΔWI) and TC were assessed using ANOVA/Tukey analysis (p < 0.05). The EE analysis revealed no statistical differences between G6 and G2 (p > 0.05). Cells in G6 exhibited higher viability and lower oxidative stress compared to other bleached groups (p < 0.05). In conclusion, employing NS + PCP + LEDv to catalyze a 35%H2O2 bleaching gel applied for 15 min to the enamel resulted in successful esthetic improvements and reduced the cytotoxicity commonly linked with traditional in-office bleaching procedures.
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Peróxido de Hidrogênio , Polímeros , Peróxido de Hidrogênio/farmacologia , Biopolímeros , Catálise , Meios de CulturaRESUMO
OBJECTIVES: to evaluate the quality and stability of adhesive interfaces established by self-etching adhesives on caries-affected primary dentin (CAD) treated with glutaraldehyde (GA) or silver diamine fluoride (SDF). METHODS: 42 primary molars were exposed to a microbiological caries-inducing protocol and divided into 6 groups according to the adhesive system (Clearfil SE - CL or FL Bond II - FL) and pretreatment (water, GA or SDF) applied on CAD. One tooth from each group was analyzed for surface modification using infrared spectroscopy. Crowns were restored with resin composite (n = 36) and cut into beams and slices. The beams were subjected to microtensile testing, Raman spectroscopy and SEM after 24 h and 6 months of storage. The slices were analyzed using Micro-Raman spectroscopy to determine the diffusion zone thickness (DZ) in each period. Data were analyzed by ANOVA and Tukey or Kruskal-Wallis and Dunn tests (α = 0.05%). RESULTS: SDF reduced the immediate bond strength for both adhesives. The control groups showed a decrease in BS after 6 months in artificial saliva. GA increased immediate DZ for FL, while SDF had the opposite effect on CL. GA decreased the DZ for FL at 6 months. There was a predominance of adhesive failures with areas of cohesive dentin fractures within control groups. SIGNIFICANCE: Modifications caused by dentin surface treatments may directly affect the performance of adhesive systems and the quality and stability of adhesive restorations.
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Adesivos , Colagem Dentária , Adesivos/farmacologia , Glutaral , Suscetibilidade à Cárie Dentária , Dentina , Resistência à Tração , Resinas Compostas/química , Adesivos Dentinários/farmacologia , Adesivos Dentinários/química , Cimentos de Resina/química , Teste de MateriaisRESUMO
OBJECTIVES: To investigate the response of pulp cells to the application of silver diamine fluoride (SDF) and potassium iodide (KI) on demineralized dentin. MATERIALS AND METHODS: The occlusal surfaces of human dentin discs (0.4 mm thick) with similar permeability were subjected to an artificial caries protocol, and then the discs were adapted into artificial pulp chambers. MDPC-23 cells were seeded on the healthy pulp dentin surface, while the demineralized surface was treated with SDF, KI, SDF + KI, or hydrogen peroxide (positive control-PC) (n = 8). The negative control (NC) received ultrapure water. After 24 h, cell viability (alamarBlue) and morphology (SEM) were evaluated. The extracts were then applied to new MDPC-23 cells seeded in culture plates to assess their viability and the formation of mineralized nodules (MN; Alizarin Red) after seven days. The data were analyzed using one-way analysis of variance/Tukey or Games-Howell tests (α = 5%). RESULTS: SDF and PC significantly reduced the viability of cells seeded on discs (45.6% and 71.0%, respectively). Only cells treated with SDF or PC detached from the dentin substrate, while the remaining cells showed altered morphology. Cells in contact with extracts showed less reduction in viability, but it was still more toxic compared to NC. Only PC reduced MN deposition. SDF + KI or KI alone did not affect the cell response. CONCLUSIONS: SDF applied alone showed a mild to moderate transdentinal cytotoxic effect on pulp cells. However, the combination of SDF + KI reduced the cytotoxic effects. Both materials used alone or in combination did not affect the mineralization ability of pulp cells. CLINICAL RELEVANCE: Besides improving esthetic results, associating potassium iodide with silver diamine fluoride may reduce the transdentinal cytotoxic effects of this cariostatic agent on pulp cells.
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Cárie Dentária , Iodeto de Potássio , Humanos , Iodeto de Potássio/farmacologia , Iodeto de Potássio/uso terapêutico , Cavidade Pulpar , Suscetibilidade à Cárie Dentária , Dentina , Estética Dentária , Fluoretos Tópicos/farmacologia , Cárie Dentária/tratamento farmacológico , Compostos de Amônio Quaternário/farmacologia , Compostos de Amônio Quaternário/uso terapêuticoRESUMO
STATEMENT OF PROBLEM: Based upon ethical questions and because of the difficulty of obtaining intact human teeth, researchers have used bovine teeth to assess the physical and mechanical properties of different dental materials. However, data from transdentinal cytotoxicity tests showing that the bovine dentin barrier is similar to the human dentin barrier is lacking. PURPOSE: The purpose of this in vitro study was to evaluate whether the bovine dentin barrier produces similar results to those obtained when the human dentin barrier is used to assess the transdentinal cytotoxicity of resin luting cements. MATERIAL AND METHODS: The number and diameter of dentinal tubules present in the human dentin barrier and bovine dentin barrier were evaluated and assessed with a t test (α=.05). After inserting the standardized dentin barriers into artificial pulp chambers, murine dental papilla-derived cells (MDPC-23) were seeded on the pulpal surface of the specimens, and the luting cements were applied to their occlusal surfaces. Then, the following groups were established for both human and bovine dentin barriers: no treatment (negative control); Single Bond Universal; RelyX Luting 2; RelyX U200; and RelyX Ultimate. After 24 hours, the viability (alamarBlue) and morphology (scanning electron microscopy) of the cells were evaluated with a 2-way analysis of variance and the Tukey honest significance test (α=.05). RESULTS: Dentinal tubules with larger diameters were observed in bovine dentin (P<.05), but the number of tubules was similar (P>.05). A reduction in viability and notable changes in the morphology of MDPC-23 cells occurred in the Single Bond Universal and RelyX Luting 2 groups in comparison with the negative control (P<.05). The RelyX U200 and RelyX Ultimate groups were statistically similar to the negative control (P>.05). No difference was found in cytotoxicity when the same luting cement was applied on human or bovine dentin barriers (P>.05). CONCLUSIONS: For transdentinal cytotoxicity tests of resin luting cements, the bovine dentin barrier proved similar results to the human dentin barrier.
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Colagem Dentária , Humanos , Bovinos , Animais , Camundongos , Colagem Dentária/métodos , Dentina , Cimentos de Resina/toxicidade , Cimentos de Resina/química , Cimentos Dentários , Bis-Fenol A-Glicidil Metacrilato/química , Teste de Materiais , Análise do Estresse DentárioRESUMO
BACKGROUND: Simulating a bacterial-induced pulpitis environment in vitro may contribute to exploring mechanisms and bioactive molecules to counteract these adverse effects. OBJECTIVE: To investigate the chronic exposure of human dental pulp cells (HDPCs) to lipopolysaccharides (LPS) aiming to establish a cell culture protocol to simulate the impaired odontogenic potential under pulpitis conditions. METHODOLOGY: HDPCs were isolated from four healthy molars of different donors and seeded in culture plates in a growth medium. After 24 h, the medium was changed to an odontogenic differentiation medium (DM) supplemented or not with E. coli LPS (0 - control, 0.1, 1, or 10 µg/mL) (n=8). The medium was renewed every two days for up to seven days, then replaced with LPS-free DM for up to 21 days. The activation of NF-κB and F-actin expression were assessed (immunofluorescence) after one and seven days. On day 7, cells were evaluated for both the gene expression (RT-qPCR) of odontogenic markers (COL1A1, ALPL, DSPP, and DMP1) and cytokines (TNF, IL1B, IL8, and IL6) and the production of reactive nitrogen (Griess) and oxygen species (Carboxy-H2DCFDA). Cell viability (alamarBlue) was evaluated weekly, and mineralization was assessed (Alizarin Red) at 14 and 21 days. Data were analyzed with ANOVA and post-hoc tests (α=5%). RESULTS: After one and seven days of exposure to LPS, NF-κB was activated in a dose-dependent fashion. LPS at 1 and 10 µg/mL concentrations down-regulated the gene expression of odontogenic markers and up-regulated cytokines. LPS at 10 µg/mL increased both the production of reactive nitrogen and oxygen species. LPS decreased cell viability seven days after the end of exposure. LPS at 1 and 10 µg/mL decreased hDPCs mineralization in a dose-dependent fashion. CONCLUSION: The exposure to 10 µg/mL LPS for seven days creates an inflammatory environment that is able to impair by more than half the odontogenic potential of HDPCs in vitro, simulating a pulpitis-like condition.
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Pulpite , Humanos , Pulpite/metabolismo , NF-kappa B , Polpa Dentária , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Escherichia coli/metabolismo , Diferenciação Celular , Citocinas/metabolismo , Células CultivadasRESUMO
OBJECTIVE: Evaluate the influence of a polymeric catalyst primer (PCP) on esthetic efficacy (EE), degradation kinetics of hydrogen peroxide (H2 O2 ), and trans-amelodentinal cytotoxicity (TC) of bleaching gels. MATERIALS AND METHODS: The following groups were established: G1: No treatment (NC, negative control); G2: PCP; G3: 10% H2 O2 ; G4: PCP + 10% H2 O2 ; G5: 20% H2 O2 ; G6: PCP + 20% H2 O2 ; G7: 35% H2 O2 (positive control); G8: PCP + 35% H2 O2 . To determine EE, enamel/dentin discs (E/DDs) were stained and subjected or not to bleaching protocols for 45 min. To assess TC, the E/DDs were adapted to artificial pulp chambers. The extracts (culture medium + gel components diffused through E/DDs) were applied to odontoblast-like MDPC-23 cells. The viability (VB), oxidative stress (OxS), morphology (SEM), amount of H2 O2 diffused and the production of hydroxyl radical (OH⢠) were assessed (two-way ANOVA/Tukey/paired Student t-test; p < 0.05). RESULTS: The highest EE was found in G8 (p < 0.05), and G4, G6, and G7 did not differ statistically (p > 0.05). In G4, the limited H2 O2 diffusion reduced OxS and increased cell VB (p < 0.05). CONCLUSIONS: Coating the enamel with PCP containing 10 mg/ml of manganese oxide before applying the 10% H2 O2 bleaching gel maintains the EE of conventional in-office bleaching and minimizes the toxic effects of this esthetic therapy. CLINICAL SIGNIFICANCE: Coating the enamel with a PCP before applying the bleaching gel may potentiate the EE of the conventional in-office tooth bleaching and reduce the toxicity of this professional therapy to the dental pulp.
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Clareadores Dentários , Clareamento Dental , Humanos , Clareamento Dental/métodos , Peróxido de Hidrogênio/farmacologia , Clareadores Dentários/farmacologia , Odontoblastos , Esmalte DentárioRESUMO
Abstract Simulating a bacterial-induced pulpitis environment in vitro may contribute to exploring mechanisms and bioactive molecules to counteract these adverse effects. Objective To investigate the chronic exposure of human dental pulp cells (HDPCs) to lipopolysaccharides (LPS) aiming to establish a cell culture protocol to simulate the impaired odontogenic potential under pulpitis conditions. Methodology HDPCs were isolated from four healthy molars of different donors and seeded in culture plates in a growth medium. After 24 h, the medium was changed to an odontogenic differentiation medium (DM) supplemented or not with E. coli LPS (0 - control, 0.1, 1, or 10 µg/mL) (n=8). The medium was renewed every two days for up to seven days, then replaced with LPS-free DM for up to 21 days. The activation of NF-κB and F-actin expression were assessed (immunofluorescence) after one and seven days. On day 7, cells were evaluated for both the gene expression (RT-qPCR) of odontogenic markers (COL1A1, ALPL, DSPP, and DMP1) and cytokines (TNF, IL1B, IL8, and IL6) and the production of reactive nitrogen (Griess) and oxygen species (Carboxy-H2DCFDA). Cell viability (alamarBlue) was evaluated weekly, and mineralization was assessed (Alizarin Red) at 14 and 21 days. Data were analyzed with ANOVA and post-hoc tests (α=5%). Results After one and seven days of exposure to LPS, NF-κB was activated in a dose-dependent fashion. LPS at 1 and 10 µg/mL concentrations down-regulated the gene expression of odontogenic markers and up-regulated cytokines. LPS at 10 µg/mL increased both the production of reactive nitrogen and oxygen species. LPS decreased cell viability seven days after the end of exposure. LPS at 1 and 10 µg/mL decreased hDPCs mineralization in a dose-dependent fashion. Conclusion The exposure to 10 µg/mL LPS for seven days creates an inflammatory environment that is able to impair by more than half the odontogenic potential of HDPCs in vitro, simulating a pulpitis-like condition.
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Gels with high concentrations of hydrogen peroxide (H2O2) have been associated with cytotoxicity and consequent post-bleaching tooth sensitivity. This study assessed the bleaching efficacy (BE) and cytotoxicity (CT) of bleaching gels with low concentrations of H2O2 containing manganese oxide (MnO2) and photocatalyzed with violet LED (LEDv). The following groups were established: G1: no treatment (negative control, NC); G2: 35% H2O2 (positive control, PC); G3: LEDv; G4: 10% H2O2; G5: 6% H2O2; G6: 10% H2O2 + MnO2 + LEDv; G7: 6% H2O2 + MnO2 + LEDv. To analyze BE, standardized enamel/dentin discs (E/DDs) were subjected to the bleaching procedures for 45 min (1 session). The color change was determined before and after performing the bleaching protocols (ΔE00; ΔWI). To analyze CT, the E/DDs were adapted to artificial pulp chambers, and the extracts (culture medium + diffused gel components) were applied to cultured odontoblast-like MDPC-23 cells. Then, the cells were assessed concerning their viability (VB), oxidative stress (OxS), and Live/Dead. The amount of H2O2 diffused was also determined (ANOVA/Tukey; p < 0.05). Cell viability decreased in all bleached groups compared to G1 (NC; p < 0.05). The cells in G6 and G7 presented higher viability than in G2, G4, and G5 (p < 0.05). The BE in G7 was similar to G2 (PC; p < 0.05). The lowest OxS and H2O2 diffusion values were found in G6 and G7, compared to the other bleached groups (G2, G4, and G5; p < 0.05). The 6% H2O2 bleaching gel (G7) submitted to both methods of catalysis (MnO2 + LEDv) caused only a mild cytotoxicity and maintained the excellent esthetic outcome promoted by in-office conventional tooth bleaching.
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Clareadores Dentários , Clareamento Dental , Peróxido de Hidrogênio , Compostos de Manganês , Óxidos , Clareamento Dental/métodos , GéisRESUMO
OBJECTIVES: This study aimed to develop and characterize different formulations of porous chitosan scaffolds (SCH) associated with calcium silicate (CaSi) and evaluate their chemotactic and bioactive potential on human dental pulp cells (hDPCs). METHODS: Different concentrations of CaSi suspensions (0.5%, 1.0%, and 2.0%, w/v) were incorporated (1:5; v/v) /or not, into 2% chitosan solution, giving rise to the following groups: SCH (control); SCH+ 0.5CaSi; SCH+ 1.0CaSi; SCH+ 2.0 CaSi. The resulting solutions were submitted to thermally induced phase separation followed by freeze-drying procedures to obtain porous scaffolds. The topography, pH, and calcium release kinetics of the scaffolds were assessed. Next, the study evaluated the influence of these scaffolds on cell migration (MG), viability (VB), proliferation (PL), adhesion and spreading (A&S), and on total protein synthesis (TP), alkaline phosphatase (ALP) activity, mineralized matrix deposition (MMD), and gene expression (GE) of odontogenic differentiation markers (ALP, DSPP, and DMP-1). The data were analyzed with ANOVA complemented with the Tukey post-hoc test (α = 5%). RESULTS: Incorporation of the CaSi suspension into the chitosan scaffold formulation increased pore diameter when compared with control. Increased amounts of CaSi in the CH scaffold resulted in higher pH values and Ca release. In Groups SCH+ 1.0CaSi and SCH+ 2.0CaSi, increased VB, PF, A&S, GE of DSPP/DMP-1 and MMD values were shown. However, Group SCH+ 2.0CaSi was the only formulation capable of enhancing MG and showed the highest increase in TP, MMD, and GE of DMP-1 and DSPP values. SIGNIFICANCE: SCH+ 2.0CaSi formulation had the highest chemotactic and bioactive potential on hDPCs and may be considered a potential biomaterial for pulp-dentin complex regeneration.
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Quitosana , Fosfatase Alcalina/metabolismo , Materiais Biocompatíveis/química , Cálcio , Compostos de Cálcio , Diferenciação Celular , Proliferação de Células , Quitosana/farmacologia , Polpa Dentária , Capeamento da Polpa Dentária , Humanos , Porosidade , Silicatos , Engenharia Tecidual , Alicerces Teciduais/químicaRESUMO
OBJECTIVE: The study aims to assess the effects of a 10% H2O2 bleaching gel with different MnO2 concentrations on the bleaching efficacy (BE), degradation kinetics (DK) of H2O2, and trans-amelodentinal cytotoxicity (TC). MATERIALS AND METHODS: Standardized bovine enamel/dentin disks (n = 96) were placed in artificial pulp chambers, and the bleaching gels were applied for 45 min. Thus, the following groups were established: (G1) no treatment (negative control/NC); (G2) 35% H2O2 (positive control/PC); (G3) 10% H2O2; (G4) 10% H2O2 + 2 mg/mL MnO2; (G5) 10% H2O2 + 6 mg/mL MnO2; and (G6) 10% H2O2 + 10 mg/mL MnO2. After analyzing bleaching efficacy (ΔE00 and ΔWI), the degradation kinetics of H2O2 and trans-amelodentinal cytotoxicity were determined (n = 8, ANOVA/Tukey; p < 0.05). RESULTS: G6 presented BE (ΔE00 and ΔWI) statistically similar to G2, which represented conventional in-office bleaching (p = 0.6795; p > 0.9999). A significant reduction in the diffusion of H2O2 occurred in G3, G4, G5, and G6 compared to G2 (p < 0.0001). The highest DK of H2O2 occurred in G6 (p < 0.0001), which had the lowest TC in comparison with all other bleached groups (p ≤ 0.0186). CONCLUSION: The addition of 10 mg/mL of MnO2 in a 10% H2O2 bleaching gel potentiates the degradation of this reactive molecule, which increases the BE of the product and decreases TC. CLINICAL SIGNIFICANCE: Replacing a 35% H2O2 gel commonly used for conventional in-office dental bleaching by a 10% H2O2 gel containing 10 mg/mL of MnO2 reduces the cytotoxicity of this professional therapy, maintaining its excellent esthetic efficacy.
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Clareadores Dentários , Clareamento Dental , Bovinos , Animais , Peróxido de Hidrogênio , Clareadores Dentários/toxicidade , Compostos de Manganês , Óxidos/toxicidade , Estética Dentária , GéisRESUMO
AIM: Guided tissue regeneration has been considered a promising strategy to replace conventional endodontic therapy of teeth with incomplete root formation. Therefore, the objective of this study was to develop a tubular scaffold (TB-SC) with poly (caprolactone)-aligned nanofibres associated with a fibronectin (FN)-loaded collagen hydrogel and assess the pulp regeneration potential mediated by human apical papilla cells (hAPCs) using an in vitro model of teeth with incomplete root formation. METHODOLOGY: Aligned nanofibre strips based on 10% poly(caprolactone) (PCL) were synthesized with the electrospinning technique to produce the TB-SCs. These were submitted to different treatments, according to the following groups: TB-SC (negative control): TB-SC without treatment; TB-SC + FN (positive control): TB-SC coated with 10 µg/ml of FN; TB-SC + H: TB-SC associated with collagen hydrogel; TB-SC + HFN: TB-SC associated with FN-loaded collagen hydrogel. Then, the biomaterials were inserted into cylindrical devices to mimic the regenerative therapy of teeth with incomplete root formation. The hAPCs were seeded on the upper surface of the TB-SCs associated or not with any treatment, and cell migration/proliferation and the gene expression of markers related to pulp regeneration (ITGA5, ITGAV, COL1A1 and COL1A3) were evaluated. The data were submitted to anova/Tukey's tests (α = 5%). RESULTS: Higher values of cell migration/proliferation and gene expression of all markers tested were observed in groups TB-SC + FN, TB-SC + H, and TB-SC + HFN compared with the TB-SC group (p < .05). The hAPCs in the TB-SC + HFN group showed the highest values of cell proliferation and gene expression of COL1A1 and COL3A1 (p < .05), as well as superior cell migration results to groups TB-SC and TB-SC + H (p < .05). CONCLUSION: Aligned nanofibre scaffolds associated with the FN-loaded collagen hydrogel enhanced the migration and proliferation of hAPCs and gene expression of pulp regeneration markers. Therefore, the use of these biomaterials may be considered an interesting strategy for regenerative pulp therapy of teeth with incomplete root formation.
Assuntos
Nanofibras , Endodontia Regenerativa , Humanos , Nanofibras/uso terapêutico , Hidrogéis , Alicerces Teciduais , Polpa Dentária , Fibronectinas , Regeneração , Colágeno , Materiais Biocompatíveis , Engenharia Tecidual/métodosRESUMO
OBJECTIVE: To assess the potential influence of violet LED (V-LED) application time on the esthetic efficacy and cytotoxicity of a 35% H2O2 bleaching gel. METHODOLOGY: Stained and standardized enamel/dentin discs were subjected to one in-office tooth bleaching session (45 min), and the gel was either irradiated or not with V-LED. Thus, the following groups were established (n = 8): G1: No treatment (negative control, NC); G2: 35% H2O2 (positive control, PC); G3: 35%H2O2 + V-LED/15 min; G4: 35%H2O2 + V-LED/30 min; G5: 35%H2O2 + V-LED/45 min. First, esthetic efficacy was assessed (ΔE00 and ΔWI). Discs assembled in artificial pulp chambers were subjected to the same bleaching treatments. Then, the extracts (culture medium + diffused bleaching gel components) were collected and applied to MDPC-23 pulp cells, which were analyzed for viability (Live/Dead, MTT) and oxidative stress (OxS). The amount of H2O2 in the extracts was also determined (leuco crystal-violet/peroxidase). The data were subjected to ANOVA/Tukey at a 5% significance level. RESULTS: Although esthetic efficacy did not differ among the irradiated groups (G3, G4, and G5) (p > 0.05), their results were higher than in G2 (PC; p < 0.05). In the irradiated groups, the cell viability and OxS as well as the amount of H2O2 in the extracts were statistically similar to G2 (PC), regardless of irradiation time (p > 0.05). CONCLUSION: Although V-LED improves the esthetic outcome of in-office tooth bleaching, increasing irradiation time does not effect the color changes and cytotoxicity of this professional therapy.
Assuntos
Fotoquimioterapia , Clareadores Dentários , Clareamento Dental , Peróxido de Hidrogênio , Fotoquimioterapia/métodos , Clareamento Dental/métodos , Clareadores Dentários/farmacologia , Sobrevivência Celular , Ácido HipoclorosoRESUMO
OBJECTIVES: To evaluate the inhibitory activity of an ion-releasing filler (S-PRG) eluate on dentin collagen-bound metalloproteinases (MMPs) and dentin matrix degradation. METHODS: Dentin beams (5 × 2 × 0.5 mm) from human molars were completely demineralized to produce dentin matrix specimens. The dry mass was measured, and a colorimetric assay (Sensolyte) determined the initial total MMP activity to allocate the beams into four treatment groups (n = 10/group): 1) water for 1 min (negative control); 2) 2% chlorhexidine digluconate (CHX - inhibitor control) for 1 min; 3) S-PRG eluate for 1 min; 4) S-PRG eluate for 30 min. After the treatments, the total MMP activity was reassessed. The specimens were stored in simulated body fluid (SBF) at 37 °C for up to 21 days. The dry mass was reassessed weekly. On day 7, the dentin matrix degradation was analyzed for the presence of collagen fragments (CF; Sirius Red) and hydroxyproline (Hyp) in the SBF. Statistical analyses were performed with ANOVA/Tukey, paired t-tests, and RM-ANOVA/Sidak (α = 5%). RESULTS: S-PRG eluate exposure for 1 and 30 min reduced (p < 0.0001) MMP activity. S-PRG exposure for 30 min presented MMP activity inhibition equivalent to CHX (p = 0.061). S-PRG and CHX decreased CF (p ≤ 0.007) and Hyp (p < 0.046) release. After 21 days of storage, S-PRG-treated beams, regardless of exposure time, presented a reduced (p ≤ 0.017) mass loss, intermediate between CHX and control. CONCLUSION: Treating demineralized dentin with S-PRG eluate for 1 or 30 min reduced matrix-bound MMP activity and dentin matrix degradation for up to 21 days. CLINICAL SIGNIFICANCE: S-PRG filler may hinder the progression of dentin carious/erosive lesions and enhance the stabilization of dentin bonding interfaces.
Assuntos
Colágeno , Dentina , Colágeno/metabolismo , Colágeno/farmacologia , Dentina/metabolismo , Humanos , Hidroxiprolina/metabolismo , Metaloproteinases da Matriz/metabolismo , Dente MolarRESUMO
This paper aimed to assess the influence of adhesive restoration interface on the diffusion of hydrogen peroxide (H2O2), indirect toxicity, and pro-inflammatory mediators expression by odontoblast-like cells, after in-office tooth whitening. Dental cavities prepared in bovine enamel/dentin discs were adhesively restored and subjected or not to hydrolytic degradation (HD). A whitening gel with 35% H2O2 (WG) was applied for 45 min onto restored and non-restored specimens adapted to artificial pulp chambers giving rise to the groups: SD- intact discs (control); SD/HP- whitened intact discs; RT/HP- restored and whitened discs; and RT/HD/HP- restored and whitened discs subjected to HD. The extracts (culture medium + WG components diffused through enamel/dentin/restoration interface) were collected and applied to odontoblast-like MDPC-23 cells. The study evaluated the amount of H2O2 in the extracts, as well as the cell viability (CV), cell morphology (CM), and gene expression of inflammatory mediators (TNF-α and COX-2) by the pulp cells exposed to the extracts (ANOVA and Tukey tests; 5% significance). All whitened groups presented lower CV than SD (control; p<0.05). The highest CV reduction and gene expression of TNF-α and COX-2 was observed in the RT/HD/HP group in comparison with SD/HP and RT/HP (control; p<0.05). CM alterations occurred in all whitened groups. The intensity of these cell side effects was directly related with the amount of H2O2 in the extracts. We concluded that adhesive restoration of dental cavity increases the H2O2 diffusion after in-office whitening, enhancing the indirect toxicity of this therapy and trigger pro-inflammatory overexpression by MDPC-23 cells.
Assuntos
Clareadores Dentários , Clareamento Dental , Animais , Bovinos , Ciclo-Oxigenase 2 , Esmalte Dentário , Peróxido de Hidrogênio/toxicidade , Mediadores da Inflamação , Clareadores Dentários/toxicidade , Fator de Necrose Tumoral alfaRESUMO
OBJECTIVE: To assess the influence of coating the enamel with a nanofiber scaffold (NS) and a polymeric catalyst primer (PCP) on the esthetic efficacy, degradation kinetics of hydrogen peroxide (H2O2), and trans-amelodentinal cytotoxicity of bleaching gels subjected or not to violet-LED irradiation. METHODOLOGY: The following groups were established (n = 8): G1- No treatment (negative control); G2- NS+PCP; G3- LED; G4- NS+PCP+LED; G5- 35% H2O2 (positive control); G6- NS+PCP+35% H2O2+LED; G7- 20% H2O2; G8- NS+PCP+20% H2O2+LED; G9- 10% H2O2; G10- NS+PCP+10% H2O2+LED. For esthetic efficacy analysis, enamel/dentin discs were stained and exposed for 45 min to the bleaching protocols. To assess the cytotoxicity, the stained enamel/dentin discs were adapted to artificial pulp chambers, and the extracts (culture medium + components diffused through the discs) were collected and applied to MDPC-23 cells, which had their viability, oxidative stress, and morphology (SEM) evaluated. The amount of H2O2 diffused and hydroxyl radical (OHâ¢) production were also determined (two-way ANOVA/Tukey/paired Student t-test; p < 0.05). RESULTS: G6 had the highest esthetic efficacy compared to the other groups (p < 0.05). Besides the esthetic efficacy similar to conventional in-office bleaching (G5; p > 0.05), G10 also showed the lowest toxic effect and oxidative stress to MDPC-23 cells compared to all bleached groups (p < 0.05). CONCLUSION: Coating the enamel with a nanofiber scaffold and a polymeric catalyst primer, followed by the application of 10%, 20%, or 35% H2O2 bleaching gels irradiated with a violet LED, stimulates H2O2 degradation, increasing esthetic efficacy and reducing the trans-amelodentinal toxicity of the treatment.