RESUMO
Fluoride is a double-edged sword. It was widely used for early caries prevention while excessive intake caused a toxicology effect, affected enamel development, and resulted in dental fluorosis. The study aimed to evaluate the protective effect and mechanism of Epigallocatechin-3-gallate (EGCG) on the apoptosis induced by fluoride in ameloblast-like cells. We observed that NaF triggered apoptotic alterations in cell morphology, excessive NaF arrested cell cycle at the G1, and induced apoptosis by up-regulating Bax and down-regulating Bcl-2. NaF activated the insulin-like growth factor receptor (IGFR), and phosphatidylinositol-3-hydroxylase (p-PI3K), while dose-dependently down-regulating the expression of Forkhead box O1 (FoxO1). EGCG supplements reversed the changes in LS8 morphology, the cell cycle, and apoptosis induced by fluoride. These results indicated that EGCG possesses a protective effect against fluoride toxicity. Furthermore, EGCG suppressed the activation of p-PI3K and the down-regulation of FoxO1 caused by fluoride. Collectively, our findings suggested that EGCG attenuated fluoride-induced apoptosis by inhibiting the PI3K/FoxO1 signaling pathway. EGCG may serve as a new alternative method for dental fluorosis prevention, control, and treatment.
Assuntos
Ameloblastos , Apoptose , Catequina , Fluoretos , Fosfatidilinositol 3-Quinases , Transdução de Sinais , Catequina/análogos & derivados , Catequina/farmacologia , Apoptose/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Animais , Fluoretos/toxicidade , Fluoretos/farmacologia , Ameloblastos/efeitos dos fármacos , Ameloblastos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Forkhead Box O1/metabolismo , Linhagem Celular , Camundongos , Fluoreto de Sódio/toxicidade , Fluorose DentáriaRESUMO
Conventional resin-based sealants release minimal fluoride ions (F) and lack antibacterial activity. The objectives of this study were to: (1) develop a novel bioactive sealant containing calcium fluoride nanoparticles (nCaF2) and antibacterial dimethylaminohexadecyl methacrylate (DMAHDM), and (2) investigate mechanical performance, F recharge and re-release, microleakage, sealing ability and cytotoxicity. Helioseal F served as commercial control. The initial F release from sealant containing 20% nCaF2 was 25-fold that of Helioseal F. After ion exhaustion and recharge, the F re-release from bioactive sealant did not decrease with increasing number of recharge and re-release cycles. Elastic modulus of new bioactive sealant was 44% higher than Helioseal F. The new sealant had excellent sealing, minimal microleakage, and good cytocompatibility. Hence, the nanostructured sealant had substantial and sustained F release and antibacterial activity, good sealing ability and biocompatibility. The novel bioactive nCaF2 sealant is promising to provide long-term F ions for caries prevention.
Assuntos
Antibacterianos , Fluoreto de Cálcio , Infiltração Dentária , Teste de Materiais , Metacrilatos , Nanopartículas , Selantes de Fossas e Fissuras , Selantes de Fossas e Fissuras/química , Antibacterianos/farmacologia , Antibacterianos/química , Fluoreto de Cálcio/química , Metacrilatos/química , Nanopartículas/química , Fluoretos/química , Fluoretos/farmacologia , Módulo de Elasticidade , Animais , Camundongos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Propriedades de Superfície , Resinas CompostasRESUMO
Dimethyloxalylglycine (DMOG) has been found to stimulate osteogenesis and angiogenesis of stem cells, promoting neo-angiogenesis in bone tissue regeneration. In this review, we conducted a comprehensive search of the literature to investigate the effects of DMOG on osteogenesis and bone regeneration. We screened the studies based on specific inclusion criteria and extracted relevant information from both in vitro and in vivo experiments. The risk of bias in animal studies was evaluated using the SYRCLE tool. Out of the 174 studies retrieved, 34 studies met the inclusion criteria (34 studies were analyzed in vitro and 20 studies were analyzed in vivo). The findings of the included studies revealed that DMOG stimulated stem cells' differentiation toward osteogenic, angiogenic, and chondrogenic lineages, leading to vascularized bone and cartilage regeneration. Addtionally, DMOG demonstrated therapeutic effects on bone loss caused by bone-related diseases. However, the culture environment in vitro is notably distinct from that in vivo, and the animal models used in vivo experiments differ significantly from humans. In summary, DMOG has the ability to enhance the osteogenic and angiogenic differentiation potential of stem cells, thereby improving bone regeneration in cases of bone defects. This highlights DMOG as a potential focus for research in the field of bone tissue regeneration engineering.
Assuntos
Aminoácidos Dicarboxílicos , Regeneração Óssea , Diferenciação Celular , Osteogênese , Células-Tronco , Regeneração Óssea/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Humanos , Diferenciação Celular/efeitos dos fármacos , Animais , Aminoácidos Dicarboxílicos/farmacologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/citologia , Células-Tronco/metabolismo , Engenharia Tecidual/métodos , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/citologia , Glicina/análogos & derivadosRESUMO
OBJECTIVE: Pit and fissure sealants with antibacterial and remineralization properties have broad application prospects in caries prevention. The objectives of this study were to: (1) develop a novel pit and fissure sealant containing CaF2 nanoparticles (nCaF2) and dimethylaminohexadecyl methacrylate (DMAHDM); and (2) investigate the effects of nCaF2 and DMAHDM on biofilm response and fluoride (F) ion release for the first time. METHODS: Helioseal F was used as a control. Bioactive sealants were formulated with DMAHDM and nCaF2. Flow properties, enamel shear bond strength, hardness and F ion releases were measured. Streptococcus mutans (S. mutans) biofilms were grown on sealants. Biofilm metabolic activity, lactic acid production, colony-forming units (CFU), and pH of biofilm culture medium were measured. RESULTS: Adding 5% DMAHDM and 20% nCaF2 did not reduce the paste flow and enamel bond strength, compared to control (p < 0.05). Hardness of sealants with 20% nCaF2 and DMAHDM was higher than control (p < 0.05). The F ion release from 20% nCaF2 was much higher than that of commercial control (p < 0.05). The sealant with DMAHDM reduced the S. mutans biofilm CFU by 4 logs. The pH in biofilm medium of the new bioactive sealant was much higher (pH 6.8) than that of commercial sealant (pH 4.66) (p < 0.05). SIGNIFICANCE: The new bioactive pit and fissure sealant with nCaF2 and DMAHDM achieved high fluoride release and strong antibacterial performance. This novel fluoride-releasing and antibacterial sealant is promising to inhibit caries and promote the remineralizaton of enamel and dentin.
Assuntos
Metacrilatos , Selantes de Fossas e Fissuras , Antibacterianos/farmacologia , Biofilmes , Fosfatos de Cálcio , Fluoretos/farmacologia , Metacrilatos/farmacologiaRESUMO
This study was to compare the influence of glass fiber post placement and crown restoration on endodontically treated maxillary first premolars with severe NCCLs using three-dimensional finite element analysis and fracture resistance testing. G1, intact teeth. G2, teeth with artificial defect. G3, composite resin (CR). G4, CR and fiber post in buccal canal (FPB). G5, CR and fiber post in palatal canal (FPP). G6, CR and fiber posts in buccal and palatal canals (FPBP). G7, CR and crown (C). G8, CR, FPB, C. G9, CR, FPP, C. G10, CR, FPBP, C. Teeth in G2, G3, and G5 showed a similar stress concentration at the tip of the defect. The fracture resistance of G2 did not differ significantly from G3 and G5 (p>0.05) but differed significantly from that in other groups (p<0.05). The fractures in G4 were more favorable, and the difference of those in G1 from those in G7, G8, G9, and G10 was statistically significant (p<0.05). Restoration of root-filled maxillary premolars with severe NCCLs using fiber post in the buccal canal may be more efficacious than other restoration methods.
Assuntos
Falha de Restauração Dentária , Restauração Dentária Permanente/métodos , Fraturas dos Dentes/prevenção & controle , Dente não Vital/terapia , Dente Pré-Molar , Resinas Compostas/química , Análise do Estresse Dentário , Análise de Elementos Finitos , Vidro , Humanos , Técnicas In Vitro , Teste de Materiais , Técnica para Retentor Intrarradicular , SoftwareRESUMO
Decreased expression and increased phosphorylation of Forkhead box o1 (Foxo1) in ameloblasts were observed both in vivo and in vitro when treated by fluoride. The present study aims to investigate the possible relationship between Foxo1 and enamel matrix proteinases, matrix metalloproteinase 20 (MMP20), and kallikrein 4 (KLK4), in NaF-treated ameloblasts. Ameloblast-like cells (LS8 cells) were exposed to NaF at selected concentration (0/2 mM) for 24 h. Gene overexpression and silencing experiments were used to up- and down-regulate Foxo1 expression. The expression levels of Foxo1, MMP20, and KLK4 were detected by quantitative real-time PCR and western blot. Dual luciferase reporter assay was performed to evaluate the regulation of Foxo1 on the transcriptional activity of KLK4 promoter. The results showed that KLK4 expression was decreased in LS8 cells treated by NaF, while MMP20 expression was not changed. Foxo1 activation led to significantly up-regulation of KLK4 in LS8 cells under NaF condition. Knockout of Foxo1 markedly decreased klk4 expression in mRNA level, and intensified inhibition occurred in LS8 cells when combined with NaF treatment. However, the variation trend of MMP20 was not clear. Dual luciferase reporter assay showed that Foxo1 activation enhanced the transcriptional activity of KLK4 promoter. These findings suggest that the decrease of Foxo1 expression induced by high fluoride was a cause for low KLK4 expression.
Assuntos
Ameloblastos/efeitos dos fármacos , Proteína Forkhead Box O1/genética , Expressão Gênica/efeitos dos fármacos , Calicreínas/genética , Fluoreto de Sódio/farmacologia , Ameloblastos/citologia , Ameloblastos/metabolismo , Animais , Linhagem Celular , Proteína Forkhead Box O1/metabolismo , Calicreínas/metabolismo , Metaloproteinase 20 da Matriz/genética , Metaloproteinase 20 da Matriz/metabolismo , CamundongosRESUMO
The aim of the study was to compare the fracture resistance of the palatal cusps of defective and endodontically treated premolars after restoration with various restorative techniques. Fifty premolars were assigned to five groups. The first group comprised intact teeth as control (G1), while the other experimental groups (G2, G3, G4 and G5) comprised endodontically-treated teeth, whose palatal cusps were cut and reduced the buccal cusps by 2 mm. G2, composite resin onlay with buccal cusp coverage (CR). G3, CR and fiber post. G4, CR and polyethylene fiber. G5, CR, fiber post and polyethylene fiber. Fracture resistance was tested. The data were recorded in Newton and submitted to ANOVA and Tukey post hoc tests. Statistically significant difference was found between the mean fracture resistances of the groups. Polyethylene fiber reinforced composite restorations strengthened the fracture resistance of palatal cusps defective and endodontically treated premolars.