RESUMO
OBJECTIVES: White spot lesions (WSL) are prevalent in patients using orthodontic appliances. The presence of ion-releasing compounds in the tooth-appliance interface may limit enamel demineralization to control WSL incidence. Thus, this study aims to evaluate the mineral formation on SiNb-containing experimental orthodontic resins and the influence of these fillers on the physicochemical and biological properties of developed materials. MATERIALS AND METHODS: The SiNb particles were synthesized via the sol-gel route and characterized by their molecular structure and morphology. Photopolymerizable orthodontic resins were produced with a 75 wt% Bis-GMA/25 wt% TEGDMA and 10 wt%, 20 wt%, or 30 wt% addition of SiNb. A control group was formulated without SiNb. These resins were tested for their degree of conversion, softening in solvent, cytotoxicity in fibroblasts, flexural strength, shear bond strength (SBS), and mineral deposition. RESULTS: The addition of 10 wt% of SiNb did not impair the conversion of monomers, cytotoxicity, and flexural strength. All groups with SiNb addition presented similar softening in solvent. The presence of these particles did not affect the bond strength between metallic brackets and enamel, with SBS values ranging from 16.41 to 18.66 MPa. The mineral deposition was observed for all groups. CONCLUSION: The use of niobium silicate as filler particles in resins may be a strategy for the adhesion of orthodontic appliances. The 10 wt% SiNb concentration resulted in a material with suitable physicochemical and biological properties while maintaining the bond strength to tooth enamel and promoting mineral deposition.
Assuntos
Colagem Dentária , Braquetes Ortodônticos , Humanos , Nióbio/química , Silicatos , Bis-Fenol A-Glicidil Metacrilato/química , Aparelhos Ortodônticos , Solventes , Teste de Materiais , Resistência ao Cisalhamento , Cimentos de Resina/químicaRESUMO
AIM: To avoid root canal recontamination and endodontic treatment failure, endodontic sealers with antibacterial activity could be an alternative. Silver nanoparticles have antibacterial activity and this study aimed to synthesize Ag@SiO2 nanoparticles, incorporate them into an experimental endodontic resin sealer and evaluate their influence on physicochemical and biological properties. METHODOLOGY: Ag@SiO2 nanoparticles were produced using the sol-gel process, based on the Stöber method. The particles were characterized in terms of their chemical structure by Fourier transform-infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), UV-Vis spectral analysis, scanning electron microscopy, and transmission electron microscopy, where the particle morphology and diameter were analysed. A dual-cured experimental endodontic resin sealer was formulated using 70 wt% UDMA, 15 wt% GDMA, and 15 wt% BisEMA. The photoinitiators were added separately in two pastes. The Ag@SiO2 nanoparticles were incorporated into the endodontic sealer at the concentrations of 2.5 wt%, 5 wt%, and 10 wt%, and a control group without nanoparticles was also formulated. The endodontic sealers were evaluated for their flow, film thickness, degree of conversion, softening in solvent, radiopacity, cytotoxicity and antibacterial activity immediately and after 9 months in water storage. RESULTS: Silver was detected in the chemical characterization of Ag@SiO2 that presented a spheric regular shape and average 683.51 nm ± 93.58 diameter. Sealers presented adequate flow and film thickness while radiopacity values were below the ones required by ISO 6876. All groups underwent softening after immersion in a solvent. The 10 wt% groups showed a higher loss of subsurface hardness (∆KHN%). No reduction in cell viability was observed. Enterococcus faecalis viability in biofilm was reduced in 10 wt% groups after 24 h and 9 months. CONCLUSION: The addition of 10 wt% Ag@SiO2 reduced E. faecalis viability at immediate and longitudinal analysis while maintaining the physicochemical properties of developed sealers.
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Nanopartículas Metálicas , Materiais Restauradores do Canal Radicular , Materiais Restauradores do Canal Radicular/farmacologia , Materiais Restauradores do Canal Radicular/química , Prata/farmacologia , Dióxido de Silício/farmacologia , Antibacterianos/farmacologia , Solventes , Teste de Materiais , Resinas Epóxi/farmacologia , Resinas Epóxi/químicaRESUMO
OBJECTIVES: This study aimed at formulating antibacterial orthodontic resins containing alkyl trimethyl ammonium bromide (ATAB) and evaluating their physicochemical and biological properties. MATERIALS AND METHODS: The chemical composition and microstructure of ATAB was characterized through FTIR and SEM, respectively. Experimental orthodontic BisGMA/TEGDMA-based resins were formulated, and the ATAB filler was incorporated at 1wt%, 5wt%, and 10wt%, along with colloidal silica (5wt%). The degree of conversion, softening in solvent, and flexural strength of the experimental resins were analyzed. Biological properties were also assessed through cytotoxicity and antibacterial analyses. RESULTS: The incorporation of ATAB, due to the presence of â¯N+(CH3)3 alkyl groups, had no adverse effect on the degree of conversion of the resins (p > 0.05). The %ΔKHN values at 5wt% and 10wt% were comparable to those of the control group, while the flexural strength was reduced at all concentrations of ATAB. The viability of the gingival fibroblast was reduced with the addition of ATAB (p < 0.05). The viability of biofilm and planktonic bacteria was reduced when ATAB was incorporated at 5wt% and 10wt%. CONCLUSIONS: The addition of ATAB at 5wt% resulted suitable for the formulation of orthodontic resins with the ability to control the biofilm formation and planktonic activity of S.mutans, without jeopardizing some specific physicochemical properties. CLINICAL RELEVANCE: White spot lesions in orthodontic patients may be controlled by preventive treatments. Non-patient-dependent strategies, such as the use of orthodontic resins containing ATAB, may avoid accumulation of bacteria, especially in those areas surrounding orthodontic appliances.
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Resinas Compostas , Streptococcus mutans , Humanos , Resinas Compostas/farmacologia , Resinas Compostas/química , Compostos de Amônio Quaternário/farmacologia , Biofilmes , Antibacterianos/farmacologia , Antibacterianos/química , Teste de Materiais , Metacrilatos/químicaRESUMO
Several studies have investigated the effects of natural products in the treatment of diseases. Traditional Amazonian populations commonly use copaiba due to its well-known anti-inflammatory, antibacterial, and healing properties. In this study, we aimed to investigate the effects of systemic administration of copaiba oleoresin (Copaifera reticulata Ducke) on ligature-induced periodontitis in rats. To do so, 21 adult rats were divided into three groups (n = 7 each): a control group, ligature-induced periodontitis group, and ligature-induced periodontitis group treated with copaiba oleoresin (200 mg/kg/day). The ligature remained from day 0 to 14, and the copaiba oleoresin was administered via oral gavage during the last seven days. On day 14, the animals were euthanized, and mandibles were collected for histopathological evaluation and microcomputed tomography analysis. Our data showed that the administration of copaiba considerably reduced the inflammatory profile. Moreover, copaiba oleoresin limited alveolar bone loss, increased trabecular thickness and bone-to-tissue volume ratio, and decreased the number of trabeculae compared with those of the untreated experimental periodontitis group. Our findings provide pioneering evidence that supports the potential of copaiba oleoresin in reducing periodontitis-induced alveolar bone damage in rats.
Assuntos
Perda do Osso Alveolar , Fabaceae , Periodontite , Perda do Osso Alveolar/tratamento farmacológico , Perda do Osso Alveolar/etiologia , Animais , Antibacterianos , Anti-Inflamatórios , Periodontite/tratamento farmacológico , Periodontite/patologia , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Resinas Vegetais , Microtomografia por Raio-XRESUMO
BACKGROUND: Alcohol (EtOH) intake during adolescence has become an important public health issue. Although the detrimental effects of EtOH intake on the musculoskeletal system are well known, only a few studies have investigated its impact on the stomatognathic system of adolescents. This study aimed to investigate the effect of EtOH binge drinking on the alveolar bone and the long-term consequences after abstinence. METHODS: Adolescent female Wistar rats (35 days old) were exposed to 4 cycles of EtOH binge drinking (3 g/kg/d; 3 days On-4 days Off) or distilled water (control group). Alveolar bone micromorphology and vertical bone distance were evaluated at 1, 30, and 60 days after that last EtOH intake through X-ray computed microtomography. The mineral:matrix ratio was assessed through Raman spectroscopy. RESULTS: A decrease in both trabecular thickness and volume ratio, and an increase in trabecular separation were observed at the 1-day evaluation (immediate withdrawal). After 30 and 60 days, the alveolar bone parameters were found similar to control, except for the mineral:matrix ratio in the long-term abstinence. CONCLUSIONS: EtOH binge drinking during adolescence results in alveolar bone damage that may persist in adulthood, even after abstinence.
Assuntos
Perda do Osso Alveolar/induzido quimicamente , Etanol/efeitos adversos , Doenças Mandibulares/induzido quimicamente , Solventes/efeitos adversos , Consumo de Álcool por Menores , Perda do Osso Alveolar/diagnóstico por imagem , Animais , Feminino , Homeostase , Doenças Mandibulares/diagnóstico por imagem , Ratos Wistar , Microtomografia por Raio-XRESUMO
Bone mineralization is a highly specific and dynamic nanoscale process that has been studied extensively from a structural, chemical, and biological standpoint. Bone tissue, therefore, may be defined by the interplay of its intricately mineralized matrix and the cells that regulate its biological function. However, the far majority of engineered bone model systems and bone replacement materials have been unable to replicate this key characteristic of bone tissue; that is, the ability of cells to be gradually and rapidly embedded in a three-dimensional (3D) heavily calcified matrix material. Here we review the characteristics that define the bone matrix from a nanostructural perspective. We then revisit the benefits and challenges of existing model systems and engineered bone replacement materials, and discuss recent efforts to replicate the biological, cellular, mechanical, and materials characteristics of bone tissue on the nano- to microscale. We pay particular attention to a recently proposed method developed by our group, which seeks to replicate key aspects of the entrapment of bone cells within a mineralized matrix with precisions down to the level of individual nano-crystallites, inclusive of the bone vasculature, and osteogenic differentiation process. In summary, this paper discusses existing and emerging evidence pointing towards future developments bridging the gap between the fields of biomineralization, structural biology, stem cells, and tissue engineering, which we believe will hold the key to engineer truly functional bone-like tissue in the laboratory.
Assuntos
Osso e Ossos/efeitos dos fármacos , Calcificação Fisiológica/efeitos dos fármacos , Hidrogéis/farmacologia , Nanoestruturas/química , Diferenciação Celular/efeitos dos fármacos , Humanos , Osteogênese/efeitos dos fármacos , Engenharia Tecidual/métodosRESUMO
We aimed to investigate the effects of chronic stress (CS) on experimental periodontitis (EP) in rats. For this, 28 Wistar rats were divided into four groups: control, ligature-induced experimental periodontitis (EP), chronic stress (CS; by physical restraint model) and CS+EP (association of chronic stress and ligature-induced periodontitis). The experimental period lasted 30 days, including exposure to CS every day and ligature was performed on the 15th experimental day. After 30 days, the animals were submitted to the behavioral test of the elevated plus maze (EPM). Next, rats were euthanized for blood and mandible collection in order to evaluate the oxidative biochemistry (by nitric oxide (NO), reduced-glutathione activity (GSH), and thiobarbituric acid reactive substance levels (TBARS)) and alveolar bone characterization (by morphometric, micro-CT, and immunohistochemistry), respectively. The behavioral parameters evaluated in EPM indicated higher anxiogenic activity in the CS and CS+EP, groups, which is a behavioral reflex of CS. The results showed that CS was able to change the blood oxidative biochemistry in CS and CS+EP groups, decrease GSH activity in the blood, and increase the NO and TBARS concentrations. Thus, CS induces oxidative blood imbalance, which can potentialize or generate morphological, structural, and metabolic damages to the alveolar bone.
Assuntos
Perda do Osso Alveolar/patologia , Estresse Oxidativo , Estresse Psicológico/sangue , Perda do Osso Alveolar/sangue , Perda do Osso Alveolar/complicações , Animais , Glutationa/sangue , Masculino , Ratos , Ratos Wistar , Estresse Psicológico/complicações , Substâncias Reativas com Ácido Tiobarbitúrico/análiseRESUMO
OBJECTIVE: To formulate an experimental methacrylate-based photo-polymerizable resin for 3D printing with ytterbium trifluoride as filler and to evaluate the mechanical, physicochemical, and biological properties. METHODS: Resin matrix was formulated with 60 wt% UDMA, 40 wt% TEGDMA, 1 wt% TPO, and 0.01 wt% BHT. Ytterbium Trifluoride was added in concentrations of 1 (G1 %), 2 (G2 %), 3 (G3 %), 4 (G4 %), and 5 (G5 %) wt%. One group remained without filler addition as control (GC). The samples were designed in 3D builder software and printed using a UV-DLP 3D printer. The samples were ultrasonicated with isopropanol and UV cured for 60 min. The resins were tested for degree of conversion (DC), flexural strength, Knoop microhardness, softening in solvent, radiopacity, colorimetric analysis, and cytotoxicity (MTT and SRB). RESULTS: Post-polymerization increased the degree of conversion of all groups (p < 0.05). G2 % showed the highest DC after post-polymerization. G2 % showed no differences in flexural strength from the G1 % and GC (p > 0.05). All groups showed a hardness reduction after solvent immersion. No statistical difference was found in radiopacity, softening in solvent (ΔKHN%), colorimetric spectrophotometry, and cytotoxicity (MTT) (p > 0.05). G1 % showed reduced cell viability for SRB assay (p < 0.05). SIGNIFICANCE: It was possible to produce an experimental photo-polymerizable 3D printable resin with the addition of 2 % ytterbium trifluoride as filler without compromising the mechanical, physicochemical, and biological properties, comparable to the current provisional materials.
Assuntos
Dureza , Teste de Materiais , Metacrilatos , Impressão Tridimensional , Metacrilatos/química , Resistência à Flexão , Polimerização , Polietilenoglicóis/química , Resinas Compostas/química , Ácidos Polimetacrílicos/química , Poliuretanos/química , Colorimetria , Propriedades de SuperfícieRESUMO
We aimed to investigate the effectiveness of physical training as a protective strategy to mitigate alveolar bone damage and blood antioxidant defense caused by ethanol (EtOH) consumption in a binge-drinking pattern. Male Wistar rats aged approximately 90 days were divided into four groups: control, training, EtOH, and training + EtOH. The physical training protocol was conducted on a treadmill for four consecutive weeks, while the animals in the EtOH group were administered EtOH via orogastric gavage for three consecutive days each week, following the binge drink pattern. After the training period, blood and mandibles were collected for plasma oxidative biochemistry analysis, and the alveolar bone was subjected to physicochemical composition analysis, tissue evaluation, and microtomography evaluation. Our results showed that EtOH induced oxidative stress and physical exercise promoted the recovery of antioxidant action. Physical training minimized the damage to the mineral/matrix composition of the alveolar bone due to EtOH consumption and increased the density of osteocytes in the trained group treated with EtOH than in those exposed only to EtOH. Furthermore, physical training reduced damage to the alveolar bone caused by EtOH consumption. Our findings suggest that physical training can serve as an effective strategy to reduce systemic enzymatic oxidative response damage and alleviate alveolar bone damage resulting from alcohol consumption. Further investigations are warranted to elucidate the underlying mechanisms and explore, in addition to physical training, the potential effects of other activities with varying intensities on managing alcohol-induced bone damage.
Assuntos
Antioxidantes , Consumo Excessivo de Bebidas Alcoólicas , Etanol , Estresse Oxidativo , Condicionamento Físico Animal , Ratos Wistar , Animais , Masculino , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Condicionamento Físico Animal/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Consumo Excessivo de Bebidas Alcoólicas/sangue , Etanol/toxicidade , RatosRESUMO
This study aimed to investigate the impact of minocycline on the alveolar bone in experimental periodontitis in rats. Thirty Wistar rats were randomly assigned to three groups: control without periodontitis; experimental periodontitis induced by ligature; experimental periodontitis + intraperitoneal administration minocycline for seven days. Ligatures remained in place in both periodontitis groups for 14 days. At the end of the experiment, the animals were euthanized and one hemimandible underwent micro-computed tomography (micro-CT) analysis to assess vertical bone loss and alveolar bone quality. Histopathological analysis was performed on the other hemimandible. Statistical analysis was performed using ANOVA with Tukey's post-test (p<0.05). The results showed a significant reduction in vertical bone loss in the animals treated with minocycline compared with untreated animals. Minocycline also preserved the alveolar bone thickness, number, spacing, and bone volume to tissue volume ratio. Histopathological analysis indicated that minocycline reduced bone resorption, decreased inflammatory response, and maintained the bone collagen fibers. This study demonstrated the effectiveness of minocycline in reducing vertical bone loss and preserved bone quality in rats with experimental periodontitis. The results of this study indicate that minocycline has the potential to serve as an additional treatment option for periodontitis. However, further research is warranted to assess the efficacy and safety of minocycline use in patients with periodontitis.
Assuntos
Perda do Osso Alveolar , Minociclina , Periodontite , Ratos Wistar , Microtomografia por Raio-X , Animais , Minociclina/farmacologia , Minociclina/uso terapêutico , Perda do Osso Alveolar/tratamento farmacológico , Perda do Osso Alveolar/patologia , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/prevenção & controle , Periodontite/tratamento farmacológico , Periodontite/patologia , Ratos , Masculino , Modelos Animais de Doenças , Antibacterianos/farmacologia , Antibacterianos/uso terapêuticoRESUMO
Apical periodontitis (AP) is a condition characterized by inflammatory and infectious components in the tooth canal. AP affects periradicular tissues and has systemic repercussions. Physical exercise is a structured activity that requires cardiorespiratory function, and can modulate the inflammatory profile in pathological conditions. As a result, this study aimed to determine the effects of aerobic physical training (PT) on the alveolar bone with and without AP, and its systemic inflammatory repercussions. AP was induced in the mandibular first molars, and PT was performed on a treadmill for five consecutive days over four weeks, with progressive increases in speed and activity time. Blood samples were collected to determine serum cytokine levels using immunoassays, and alveolar bone samples were collected for histopathological evaluation, lesion volume and microarchitecture assessment using computed microtomography. Animals with AP had increased pro-inflammatory cytokines levels compared to those without AP; however, these levels were attenuated or restored by PT. Compared to the AP group, the AP + PT group had a smaller lesion volume and greater preservation of the bone trabeculae in the remaining alveolar bone surrounding the lesion. In overall, PT minimized the severity of AP proving to be a valid strategy for individuals undergoing endodontic treatment.
Assuntos
Citocinas , Periodontite Periapical , Humanos , Animais , Periodontite Periapical/terapia , Periodontite Periapical/patologia , Exercício Físico , Osso e Ossos/patologiaRESUMO
The aim of this study was to develop an experimental composite resin with the addition of myristyltrimethylammonium bromide (MYTAB) and α -tricalcium phosphate (α-TCP) as an antibacterial and remineralizing material. Experimental composite resins composed of 75 wt% Bisphenol A-Glycidyl Methacrylate (BisGMA) and 25 wt% Triethylene Glycol Dimethacrylate (TEGDMA) were produced. Some 1 mol% Trimethyl benzoyl-diphenylphosphine oxide (TPO) was used as a photoinitiator, and butylated hydroxytoluene (BTH) was added as a polymerization inhibitor. Silica (1.5 wt%) and barium glass (65 wt%) particles were added as inorganic fillers. For remineralizing and antibacterial effect, α-TCP (10 wt%) and MYTAB (5 wt%) were incorporated into the resin matrix (α-TCP/MYTAB group). A group without the addition of α-TCP/MYTAB was used as a control. Resins were evaluated for their degree of conversion (n = 3) by Fourier Transform Infrared Spectroscopy (FTIR). The flexural strength (n = 5) was assessed based on ISO 4049:2019 requirements. Microhardness was assessed to calculate softening in solvent (n = 3) after ethanol immersion. The mineral deposition (n = 3) was evaluated after immersion in SBF, while cytotoxicity was tested with HaCaT cells (n = 5). Antimicrobial activity (n = 3) was analyzed against S. mutans. The degree of conversion was not influenced by the antibacterial and remineralizing compounds, and all groups reached values > 60%. The α-TCP/MYTAB addition promoted increased softening of polymers after immersion in ethanol and reduced their flexural strength and the viability of cells in vitro. A reduction in S. mutans viability was observed for the α-TCP/MYTAB group in biofilm formation and planktonic bacteria, with an antibacterial effect > 3log10 for the developed materials. Higher intensity of phosphate compounds on the sample's surface was detected in the α-TCP/MYTAB group. The addition of α-TCP and MYTAB promoted remineralizing and antibacterial effects on the developed resins and may be a strategy for bioactive composites.
RESUMO
The use of 3D printing in pharmaceutics has grown over the last years, along with the number of studies on the impact of the composition of these formulations on their pharmaceutical and biopharmaceutical properties. Recently, we reported the combined effect of the infill percentage and the presence of a pore former on the drug release behaviour of 3D printed matrix solid forms prepared by fused deposition modelling. However, there are some open questions about the effect of the drug solubility and the size of these dosage forms on their controlled release properties. Therefore, we produced poly(Æ-caprolactone) filaments containing different soluble forms of dexamethasone (free acid, DEX; acetate ester, DEX-A; and phosphate salt, DEX-P), which showed suitable mechanical properties and printability. 3D printed solid forms were produced in two different sizes. The formulations composed of DEX-P released about 50% of drug after 10 h, while those containing DEX or DEX-A released about 9%. The drug release profiles from the 3D printed forms containing the same drug form but with different sizes were almost completely overlapped. Therefore, these 3D printed matrix solid forms can have their drug content customised by adjusting their size, without changing their controlled release behaviour.
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Bone defects may occur in different sizes and shapes due to trauma, infections, and cancer resection. Autografts are still considered the primary treatment choice for bone regeneration. However, they are hard to source and often create donor-site morbidity. Injectable microgels have attracted much attention in tissue engineering and regenerative medicine due to their ability to replace inert implants with a minimally invasive delivery. Here, we developed novel cell-laden bioprinted gelatin methacrylate (GelMA) injectable microgels, with controllable shapes and sizes that can be controllably mineralized on the nanoscale, while stimulating the response of cells embedded within the matrix. The injectable microgels were mineralized using a calcium and phosphate-rich medium that resulted in nanoscale crystalline hydroxyapatite deposition and increased stiffness within the crosslinked matrix of bioprinted GelMA microparticles. Next, we studied the effect of mineralization in osteocytes, a key bone homeostasis regulator. Viability stains showed that osteocytes were maintained at 98% viability after mineralization with elevated expression of sclerostin in mineralized compared to non-mineralized microgels, indicating that mineralization effectively enhances osteocyte maturation. Based on our findings, bioprinted mineralized GelMA microgels appear to be an efficient material to approximate the bone microarchitecture and composition with desirable control of sample injectability and polymerization. These bone-like bioprinted mineralized biomaterials are exciting platforms for potential minimally invasive translational methods in bone regenerative therapies.
RESUMO
Thermoplastic polymers have been used to produce filaments by hot melt extrusion (HME), which can be applied to obtain 3D printlets by fused deposition modelling (FDM). Poly(ε-caprolactone) (PCL) is a low melting point thermoplastic polymer that provides HME filaments with excellent mechanical and printability properties. However, due to the highly hydrophobic properties of PCL, they afford printlets with slow drug release behaviour. We hypothesized that blending a less hydrophobic polymer, the Eudragit E (EudE), with PCL could be an approach to increase the drug release rate from PCL 3D printlets. PCL and EudE were blended at different proportions, 50:50, 60:40, 70:30, and 80:20 (w/w), to produce HME filaments. They were produced with dexamethasone at 5 % (w/w) and were effectively extruded and printable by FDM, except that composed of 50:50 (w/w). Printlets had homogeneous distribution of their components. Their drug release behaviour was dependent on the ratio of the polymeric blends. The highest EudE ratio (60:40 w/w) afforded printlets showing the highest release rate. Therefore, adding up to 40 % (w/w) of EudE to PCL does not impair the mechanical and printability properties of its HME filaments. This innovative approach is proposed here to modulate the drug release behaviour from PCL printlets.
Assuntos
Polímeros , Tecnologia Farmacêutica , Liberação Controlada de Fármacos , Polímeros/química , Impressão Tridimensional , Comprimidos/químicaRESUMO
This study aims to assess the resin composite purchases in a public health system and understand the variables associated with its cost and with the decision-making process over a period of 10 years. Secondary data collection was performed using the Brazilian Healthcare Prices Database (BDHP) from 2010 to 2019. All conventional and bulk-fill composites were selected. Date of purchase, institution type and location, procurement modality, number of purchased items, manufacture, and unit prices were collected. A multiple linear regression model assessed the influence of price in the procurement variables, while a multinomial logistic regression compared purchase probabilities between the materials. In total, 18,138 observations were collected with 2,129,294 purchased units and a total cost of USD 43,504,260.00. Conventional composites appeared in 98.5% of the procurement process. Nanofilled conventional composites were the most purchased materials, with an increased probability of purchase over time, despite its higher prices. An increase in prices was predicted for bulk-fill materials when compared to conventional ones. The odds of purchasing this category increased by 3.14x for every price increase over the years. Sociodemographic and type of institution influences the prices and the probability of procurement in the healthcare system. Nanofilled and bulk-fill resin are increasingly included in clinical practice. These findings highlight possible modifications to the standard-of-care in restorative treatments and how the translation of knowledge may occur from the development of new materials to the clinical application considering the economic impact of these modifications.
Assuntos
Resinas Compostas , Saúde Pública , Brasil , Comércio , Atenção à Saúde , HumanosRESUMO
This study aimed to screen the public procurement for dental adhesives in a public health system and evaluate the variables associated with the type and cost of purchased materials. A time series was conducted with secondary data collated from the Brazilian Databank of Healthcare Prices (BDHP). All public procurements for adhesive systems registered from 2010 to 2019 were collated. The frequency of purchase was described, and a multiple linear regression model was used to assess the influence of unit price on predictor variables. Multinomial logistic regression was conducted to describe the influence of selected variables on the probability of purchase for different classes of adhesive systems. A total of 2,752 purchases were analyzed, and the total cost of these materials reached US$ 7,022,659.00 in the 10 analyzed years. The 3-step Etch & Rinse adhesives corresponded to 45.63% of the processes, with increased probability of being purchased over time. The process conducted by public universities in recent years, using the auction modality, presented lower unit prices. The year of purchase, the type of institutions, the institution's location, and the procurement modality influenced the procurement process. The performed analyses contribute to the understanding of the variables associated with the procurements for adhesive systems, providing valuable information for rationalizing public expenditure and for implementing evidence-based practices to guarantee cost-effective and clinically effective procedures for users of the Brazilian public healthcare system.
Assuntos
Colagem Dentária , Ciência Translacional Biomédica , Brasil , Cimentos Dentários , Adesivos Dentinários , Fatores Econômicos , Cimentos de ResinaRESUMO
This study aimed to produce poly(butylene adipate-co-terephthalate) (PBAT)/niobium containing bioactive glasses (BAGNb) composites scaffolds produced by fused deposition modeling (FDM) printing and evaluate their physicochemical and biological properties in vitro and in vivo. The composite filaments were produced by melt-extrusion with the addition of 10 wt% of BAGNb (PBAT/BAGNb). Filaments without BAGNb were produced as the control group (PBAT). The filaments were characterized and were used to produce 3D-printed scaffolds using FDM. The scaffolds' structure and surface properties were assessed. In vitro cell, proliferation, and cell mineralization analysis were performed. In vivo data was obtained in the rat femur model (n = 10), and the bone repair was assessed after 15, 30, and 60 postoperative days. The printed structures presented 69.81% porosity for the PBAT/BAGNb group and 74.54% for the PBAT group. Higher cell mineralization was observed for the PBAT/BAGNb group. The in vivo data showed that the PBAT/BAGNb presented new bone formation comparable to positive controls. The combination of PBAT and BAGNb in 3D-printed scaffolds may be an alternative to produce bioactive materials with controllable shapes and properties for bone regeneration treatments.
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Nióbio , Poliésteres , Adipatos , Alcenos , Animais , Ácidos Ftálicos , Poliésteres/química , Poliésteres/farmacologia , Impressão Tridimensional , RatosRESUMO
Dental caries is a biofilm-mediated, diet-modulated, multifactorial and dynamic disease that affects more than 90% of adults in Western countries. The current treatment for decayed tissue is based on using materials to replace the lost enamel or dentin. More than 500 million dental restorations are placed annually worldwide, and materials used for these purposes either directly or indirectly interact with dentin and pulp tissues. The development and understanding of the effects of restorative dental materials are based on different in-vitro and in-vivo tests, which have been evolving with time. In this review, we first discuss the characteristics of the tooth and the dentin-pulp interface that are unique for materials testing. Subsequently, we discuss frequently used in-vitro tests to evaluate the biocompatibility of dental materials commonly used for restorative procedures. Finally, we present our perspective on the future directions for biological research on dental materials using tissue engineering and organs on-a-chip approaches. STATEMENT OF SIGNIFICANCE: Dental caries is still the most prevalent infectious disease globally, requiring more than 500 million restorations to be placed every year. Regrettably, the failure rates of such restorations are still high. Those rates are partially based on the fact that current platforms to test dental materials are somewhat inaccurate in reproducing critical components of the complex oral microenvironment. Thus, there is a collective effort to develop new materials while evolving the platforms to test them. In this context, the present review critically discusses in-vitro models used to evaluate the biocompatibility of restorative dental materials and brings a perspective on future directions for tissue-engineered and organs-on-a-chip platforms for testing new dental materials.
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Cárie Dentária , Dentina , Adulto , Resinas Compostas , Materiais Dentários/farmacologia , Restauração Dentária Permanente , Humanos , Dispositivos Lab-On-A-Chip , Teste de MateriaisRESUMO
The importance of fluoride (F) for oral health is well established in the literature. However, evidence suggests that excessive exposure to this mineral is associated with adverse effects at different life stages and may affect many biological systems, especially mineralized tissues. The purpose of this study was to investigate the effects of F exposure during pregnancy and breastfeeding on the alveolar bone of the offspring since the alveolar bone is one of the supporting components of the dental elements. For this, the progeny rats were divided into three groups: control, 10 mg F/L, and 50 mg F/L for 42 (gestational and lactation periods). Analysis of the quantification of F levels in the alveolar bone by particle-induced gamma emission; Raman spectroscopy to investigate the physicochemical aspects and mineral components; computed microtomography to evaluate the alveolar bone microstructure and analyses were performed to evaluate osteocyte density and collagen quantification using polarized light microscopy. The results showed an increase in F levels in the alveolar bone, promoted changes in the chemical components in the bone of the 50 mg F/L animals (p < 0.001), and had repercussions on the microstructure of the alveolar bone, evidenced in the 10 mg F/L and 50 mg F/L groups (p < 0.001). Furthermore, F was able to modulate the content of organic bone matrix, mainly collagen; thus, this damage possibly reduced the amount of bone tissue and consequently increased the root exposure area of the exposed groups in comparison to a control group (p < 0.001). Our findings reveal that Fcan modulate the physicochemical and microstructural dimensions and reduction of alveolar bone height, increasing the exposed root region of the offspring during the prenatal and postnatal period. These findings suggest that F can modulate alveolar bone mechanical strength and force dissipation functionality.