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OBJECTIVE: To evaluate the plant-derived compound lignin (LIG) as a pretreatment of intraradicular dentin in combination with EDTA on push-out bond strength (PBS) and nanoleakage of the glass fiber posts (GFPs) cemented using adhesive resin cement. MATERIAL AND METHODS: Twenty-eight human incisor roots were prepared for GFP cementation and divided based on dentin pretreatment: (1) CONTROL: no pretreatment, (2) EDTA: 17% EDTA for 3 min, (3) EDTA-LIG: 17% EDTA and 2% lignin for 3 min, (4) EDTA-PAC: 17% EDTA and 2% lignin for 3 min. The GFPs were cemented using the self-adhesive resin cement Multilink Speed. The roots (n = 7) were sectioned into 1 mm-thick discs and subjected to PBS testing after 1 week or 6 months. Nanoleakage was analyzed by SEM. Statistical analysis was performed using two-factor ANOVA and Tukey's test (p < 0.05). RESULTS: Higher PBS was identified for the CONTROL group (p < 0.001). After 6 months, the EDTA-LIG maintained the bond strength with a predominance of mixed failures, while the EDTA-PAC, EDTA, and CONTROL groups showed reduction of bond strength, with a predominance of adhesive failures along with severe silver infiltration in the interface. CONCLUSION: LIG associated with EDTA as a pretreatment for intraradicular dentin shows significant potential for attaining stable bond strength and interfacial integrity of self-adhesive resin cement to intraradicular dentin.

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ETHNOPHARMACOLOGICAL RELEVANCE: Amid all the Brazilian phytodiversity, in all its shades and shapes, black and white amorphous masses glued to the barks of Burseraceae species stand out as some of the nation's most appreciated plant medicinal resources. Burseraceae resins have been used in all macroregions of Brazil, wherever they occur, for a variety of medicinal purposes. However, despite ongoing interest in them, their cultural and health relevance in the country has been underexamined. AIM OF THE STUDY: This review aimed to illuminate the therapeutic importance and potential of Brazilian Burseraceae by assembling the ethnomedicinal, chemical, and pharmacological data available on its resins used in Brazil. MATERIALS AND METHODS: A search for journal articles documenting local ethnomedicinal uses of Burseraceae resins and reporting chemical and pharmacological data associated with their botanical sources was conducted in ScienceDirect, Google Scholar, and PubMed databases. Books and theses were also appraised for such information. RESULTS: At least 21 Burseraceae taxa, belonging to Protium, Trattinnickia, and Commiphora, are recorded as sources of medicinal resins in Brazil. Protium and Trattinickia yield oleoresins typically rich in mono- and triterpenoids, especially the pentacyclic triterpenoids α- and ß-amyrin. Although Commiphora oleo-gum-resins are expected to differ significantly from Protium and Trattinickia oleoresins by the presence of gum fractions, they often exhibit distinct terpenoid compositional patterns, characterized by a high proportion of sesquiterpenoids and tetracyclic triterpenoids. Burseraceae resins are more frequently cited in the Brazilian ethnomedicinal literature for relieving headaches and healing wounds. Pharmacological evidence corroborates the potential of Burseraceae resins against these and some other conditions and diseases, however, further studies are needed to confirm their efficacy and safety when used topically and through inhalation-the two primary routes of administration explored for them in Brazil. CONCLUSIONS: The present review unearths a consistent, persistent, and cross-cultural pattern of using Burseraceae resins against pain conditions. But to really tap into the Burseraceae's therapeutic potential in Brazil, we first need to address the following gaps: (a) conduct more thorough pharmacological studies, including clinical trials; (b) give more attention to the triterpenoid fraction of Burseraceae oleoresins, not only to essential oils and α- and ß-amyrin; and (c) deepen our understanding of the impact of resin aging on chemical composition.

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Orchids offer a variety of floral rewards to pollinators. In many orchid groups, however, the transfer of pollen is based on food-deception, as in the case of Laelia (including Schomburgkia s.s.), a genus assigned to the Neotropical subtribe Laeliinae. Here, we report on the reproductive biology of a Brazilian member of this subtribe, namely, Laelia gloriosa, occurring in the forested areas of southeastern Brazil. The study includes analyses of floral morphology, histochemistry, and the chemical analysis of floral rewards and scents. Pollinators and pollination mechanism data were collected in the field by means of focal observations. Analyses of breeding systems and the percentage of potentially viable seed were also recorded. The floral morphology of Laelia gloriosa indicates that this species is melittophilous. The flowers release a citrus-like fragrance that attracts many species of bee. The flowers offer waxy material as a reward, and this is collected exclusively by Meliponini bees. Several bee species visit the flowers. However, those of L. gloriosa are pollinated exclusively by Trigona spinipes. Pollinaria are deposited on the bee's scutellum. Plants of the studied population were entirely self-compatible, but pollinator-dependent. The frequency of visits to these flowers was greater than in rewardless Laeliinae. Our study provides the first evidence of lipoidal substances as a resource in Laeliinae. The discovery that an orchid species (Laelia gloriosa) of this subtribe, hitherto considered to be entirely pollinated by nectar-seeking pollinators, offers a floral waxy material and provides new insights into the evolution of this important subtribe.

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BACKGROUND: Use of flowable resin composites for ocluso-proximal restorations in primary molars could improve cervical adaptation, and reduce the failure risk. AIM: To investigate the fracture strength of occluso-proximal restorations in primary teeth using different flowable resin composites (as an intermediate layer or entire cavity) and a conventional resin composite (incremental technique). DESIGN: Two standardized occluso-proximal cavities were prepared on mesial and distal surfaces of 50 sound primary molars. The teeth were randomly assigned into five groups (n = 10): 2 mm Filtek Bulk Fill Flow + Z350 XT; 4 mm Filtek Bulk Fill Flow; 2 mm Z350 XT Flow + Z350 XT; 4 mm Z350 XT Flow; and Z350 XT inserted by incremental technique. All restored teeth were subjected to cariogenic challenge and then submitted to fracture strength test. The failure pattern of each specimen was categorized as reparable or irreparable/need for replacement based on the World Dental Federation (FDI) criteria. Fracture strength means were submitted to one-way ANOVA and Tukey's post hoc tests. Failure pattern was analyzed descriptively. RESULTS: There was no statistically significant difference on fracture strength among groups (p = .48). A similar distribution of reparable (35%-40%) and irreparable (60%-65%) failures was observed among groups. CONCLUSION: Based on a laboratorial setting, the use of different flowable resin composites (as an intermediate layer or entire cavity) may be an option to restore occluso-proximal cavities in primary molars.

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OBJECTIVE: To evaluate the effect of different modeling agents on color changes, surface roughness, and translucency parameters over time in Bulkfill resin composites. MATERIAL AND METHODS: Sixty specimens were prepared using three Bulkfill resin composites (Tetric N-Ceram Bulkfill, Filtek One Bulkfill and Opus Bulkfill) and three modeling agents (Wetting Resin, Optibond FL and Ambar APS). All specimens were subjected to a simulated tooth-brushing (Baseline, 50.000 cycles, 100.000 cycles), and surface roughness was measured at each interval. Surface topography was evaluated. The translucency parameter and color changes were assessed after 24-h, 7-, 14- and 30-day immersion in water, wine, and coffee. Data was analyzed using ANOVA and Bonferroni test. RESULTS: All specimens increased roughness after simulated tooth-brushing (p < 0.05). Wetting Resin decreased roughness on Tetric N-Ceram Bulkfill (p < 0.05). The translucency parameter remained unaltered for all groups. All groups changed color after 30-days of immersion in wine and coffee (p < 0.05). Ambar APS and Wetting Resin on Tetric N-Ceram Bulkfill showed higher color changes when immersed in coffee (p < 0.05). CONCLUSION: The use of modeling agents does not jeopardize translucency properties but may affect surface roughness and color properties of Bulkfill resin composites depending on their composition. CLINICAL SIGNIFICANCE: The findings of this study suggest that surface roughness and color properties are affected by the differences in the composition between modeling agents and Bulkfill resins composites.

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PURPOSE: To evaluate, through in vitro studies, the bond strength of vitreous and hybrid ceramics with self-etching surface treatment compared to conventional treatment. METHODS: This systematic review followed the preferred reporting items for systematic reviews and meta-analyses (PRISMA) and was registered on the open science framework (OSF) platform for in vitro studies. A population, intervention, control, and outcome (PICO) question was formulated: "Does the surface conditioning of glass and hybrid ceramics with self-etching silane present a bond strength similar to that of conventional bonding?". A literature search was carried out in the PubMed, Embase, Web of Science, Cochrane Library, and ProQuest databases until September 2023. The Joanna Briggs Institute (JBI) critical appraisal guidelines for quasi-experimental studies were used for risk assessment of bias. The meta-analysis was based on the inverse variance (IV) method (p < 0.05). RESULTS: A total of 29 in vitro studies published between 2017 and 2022 were included in this systematic review, totaling 1889 ceramic samples. The meta-analysis indicated a significant decrease in the bond strength of HF 4%-5% with silane compared to self-etching (p < 0.05; MD: 0.34; 95% CI: 0.13-0.35; I2 = 3%, p = 0.42), while it indicated that there was no significant difference between self-etching compared to 9%-10% HF with silane (p = 0.92; MD: 0.02; 95% CI: -0.32 to 0.36; I2 = 14%, p = 0.32). CONCLUSION: Self-etching primer presents bond strength that is superior to or similar to conventional surface treatment on glass and hybrid ceramics.

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This systematic review aims to evaluate whether the application of antioxidant solutions can enhance the bond strength of resin-based materials to sodium hypochlorite (NaOCl)-treated dentin. This study follows the PICOT strategy: population (sodium hypochlorite-treated dentin), intervention (application of antioxidants), control (distilled water), outcome (bond strength), and type of studies (in vitro studies). The systematic review and meta-analysis were conducted following PRISMA guidelines. Electronic databases were searched for in vitro studies evaluating the effects of antioxidants on bond strength to sodium hypochlorite-treated dentin. Two independent reviewers screened articles, extracted data, and assessed risk of bias. Meta-analyses were performed using a random-effects model to compare standardized mean differences in bond strength between antioxidant pretreatment and control groups. Inclusion criteria consisted of in vitro studies that examined the bond strength of resin-based materials to NaOCl-treated dentin with antioxidant application, while exclusion criteria included studies with incomplete data, those not using a control group, or those that did not directly measure bond strength. From 3041 initial records, 29 studies were included in the qualitative analysis and 25 in the meta-analysis. Ascorbic acid, sodium ascorbate, grape seed extract, green tea, and rosmarinic acid significantly improved bond strength to sodium hypochlorite-treated dentin (p < 0.05). The effectiveness of grape seed extract varied with adhesive system type. Hesperidin, p-toluene sulfonic acid, and sodium thiosulfate did not significantly improve bond strength. Most studies had a high risk of bias. This suggests that the conclusions drawn from these studies should be interpreted with caution, and further research with more robust methodologies may be needed to confirm the findings. In conclusion, this systematic review implies that certain antioxidants can improve bond strength to sodium hypochlorite-treated dentin, with efficacy depending on the specific agent and adhesive system used. Further standardized studies are needed to optimize protocols and confirm these findings.

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This study evaluated the impact of different repair protocols on a composite resin substrate using distinct bonding agents submitted or not to artificial aging. Unopened sets of a single-step universal adhesive system (UA) and silane-coupling agents, a single-step pre-hydrolyzed (PH) or a two-step immediately hydrolyzed (IH), were used. Half of the sets were subjected to artificial aging being stored at 48 °C for 30 days, while the other half remained unaged. The composite resin substrates were prepared and aged in distilled water, sandblasted (Al2O3), and cleaned. Then the different repair protocols were applied according to the groups. UA was used without a previous silane layer, while PH and IH were applied followed by a single-step etch-and-rinse adhesive system. Adhesive systems were light-activated, and four composite resin cylinders were formed over the substrate. After 24 h, the specimens were subjected to microshear bond strength (µSBS) test and failure mode analysis. The µSBS data were subjected to two-way ANOVA followed by Tukey HSD; Kruskal-Wallis analysis was used for failure mode distribution (α = 0.05). After aging the products, UA showed higher bond strength, while PH had significantly lower results, and IH showed no significant differences (p = 0.157). No significant differences were found for bond strength among the repair protocols when using non-aged products (p > 0.05). The protocols using UA and IH showed no significant differences between aged and non-aged bottles, whereas PH exhibited lower bond strength when comparing aged and non-aged products. More cohesive failures were observed in the resin substrate for the IH group without aging.

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Background: Adhesion to zirconia remains a significant dental challenge. This study is aimed at assessing the bond strength of zirconia based on surface treatment with pre or postsintering sandblasting associated with different chemical treatments and resin cements. Methods: Zirconia blocks were divided into 12 experimental groups based on the surface treatment (presintering sandblasting or postsintering sandblasting/tribochemical abrasion treatment), chemical treatment (none, Single Bond Universal, or Signum Zirconia Bond), and choice of cement (Panavia F or RelyX™ U200). The bond strength was measured by shear tests using a universal testing machine. The fracture analysis was performed using stereomicroscopy. Data were analyzed using three-way ANOVA and Tukey's test (α = 5%). Results: Triple and double factor's interactions were not significant (p > 0.05). Regarding the surface treatment factor, the bond strength following postsintering sandblasting treatment associated with tribochemical abrasion (9.15 ± 3.62 MPa) was significantly higher than presintering sandblasting treatment (5.24 ± 3.53 MPa). Concerning the chemical treatment factor, bond strengths were ranked as follows: Signum Zirconia Bond > Single Bond Universal > no treatment. The bond strength of the resin cements did not differ among them. Most fractures (67%) were classified as adhesive, and 32% were categorized as mixed fractures. Conclusion: Surface treatment via postsintering sandblasting combined with tribochemical abrasion demonstrated superior efficacy than in presintering sandblasting. Additionally, chemical treatment with zirconia primer increased the bond strength of zirconia irrespective of the surface physical treatment.

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Objetivo: Determinar in vitro si la microdureza superficial Knoop de las manchas blancas mejora con la infiltración de resinas de baja viscosidad en comparación con la microdureza del esmalte sano. Materiales y métodos: Se desmineralizaron 93 muestras de esmalte bovino simulando lesiones de manchas blancas, para luego ser tratadas mediante la infiltración de resinas. Se midió la microdureza Knoop de las muestras antes de desmineralizarlas, luego de este proceso y a continuación de la infiltración. Resultados: Las muestras desmineralizadas mostraron una disminución del 50% en la microdureza. La infiltración con resinas mejoró esta propiedad, aunque los valores obtenidos se encontraron muy por debajo de la microdureza del esmalte sano. El análisis estadístico, mediante análisis de varianza (ANOVA) y prueba post-hoc de Tukey, mostraron diferencias estadísticamente significativas entre los tres grupos (p<0.001). Conclusiones: El tratamiento de las lesiones de manchas blancas artificiales con resinas infiltrantes aumentó la dureza Knoop, pero sin recuperar totalmente los valores próximos a la dureza del esmalte sano. (AU)

Aim: Determine in vitro if the Knoop surface microhardness of white spots lesions improve with the infiltration of low viscosity resins and compare it with the microhardness of healthy enamel. Materials and methods: 93 samples of bovine enamel were demineralized simulating white spot lesions, and then treated by infiltration of resins. The Knoop microhardness of the samples was measured before demineralization, after this process and after infiltration. Results: Demineralized samples showed a decrease in microhardness of 50%. The infiltration with resins improved this property, although the obtained values were far below the microhardness of healthy enamel. The statistical analysis, through analysis of variance (ANOVA) and Tukey's posthoc test, showed statistically significant differences between groups (p<0.001). Conclusions: Treatment of artificial white spot enamel lesions with infiltrating resins increased Knoop hardness but failed to reach values close to the hardness of healthy enamel. (AU)

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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.

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OBJECTIVES: To evaluate the marginal integrity (MI%) and to characterize specific properties of a thermoviscous bulk-fill resin composite, two regular bulk-fill resin composites, and a non-bulk-fill resin composite. MATERIALS AND METHODS: VisCalor bulk (VBF), Filtek One Bulk Fill (OBF), and Aura Bulk Fill (ABF) were evaluated. Filtek Z250 XT (ZXT) was used as non-bulk-fill control. MI% was evaluated in standardized cylindrical cavities restored with the composites by using a 3D laser confocal microscope. The following properties were characterized: volumetric polymerization shrinkage (VS%), polymerization shrinkage stress (Pss), degree of conversion (DC%), microhardness (KHN), flexural strength (FS), and elastic modulus (EM). Data were analyzed by one-way and two-way ANOVA, and Tukey HSD post-hoc test (α = 0.05). RESULTS: VBF presented the highest MI% and the lowest VS% and Pss (p < 0.05). DC% ranged from 59.4% (OBF) to 71.0% (ZXT). ZXT and VBF presented similar and highest KHN than OBF and ABF (p < 0.05). ABF presented the lowest FS (p < 0.05). EM ranged from 5.5 GPa to 7.7 GPa, with the values of ZXT and VBF being similar and statistically higher than those of OBF and ABF (p < 0.05). CONCLUSIONS: Thermoviscous technology employed by VisCalor bulk was able to improve its mechanical behavior comparatively to regular bulk-fill resin composites and to contribute to a better marginal integrity in restorations built up in cylindrical cavities with similar geometry to a class I cavity as well. Although presenting overall better physicomechanical properties, Z250 XT presented the worst MI%. CLINICAL RELEVANCE: The marginal integrity, which is pivotal for the success of resin composite restorations, could be improved using VisCalor bulk-fill. The worst MI% presented by Z250 XT reinforces that non-bulk-fill resin composites shall not be bulk-inserted in the cavity to be restored.

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PURPOSE: To evaluate the effect of different surface treatments and adhesive cementation on the miniflexural strength (MFS) of monolithic zirconia. MATERIALS AND METHODS: Two-hundred and forty (240) sintered bars of translucent zirconia (ZT) and ultra-translucent zirconia (ZUT) were obtained (8 mm ×2 mm ×1 mm). The bars were divided into 16 groups (n = 15) according to the factors "Zirconia" (ZT and ZUT), "Cementation" (Cem) and "surface treatment" (Ctrl:Control, Al:Aluminum oxide/Al2O3 50 µm, Si:Silica/SiO2 coated alumina particles oxide 30 µm, Gl:Glazing+hydrofluoric acid). Half of the bars received an adhesive layer application, followed by application of resin cement and light curing. The surface roughness was measured in non-cemented groups. All the bars were subjected to the MFS test (1.0 mm/min; 100 kgf). Scanning electron microscopy was used for qualitative analyses. MFS data (MPa) and roughness (µm) were statistically evaluated by three-way and two-way ANOVA respectively and Tukey's test (5%). RESULTS: The surface treatment and the interaction were significant for roughness. Glazing promoted less roughness compared to silicatization. Regarding MFS, only the zirconia and surface treatment factors were significant. For ZT, the sandblasted groups had an increase in MFS and glazing reduced it. There was no difference between the groups without cementation for the ZUT; however, ZUT.Si/Cem, and ZUT.Al/Cem obtained superior MFS among the cemented groups. CONCLUSIONS: Sandblasting increases the flexural strength for ZT, while glaze application tends to reduce it. Applying resin cement increases the flexural strength of ZUT when associated with sandblasting. Sandblasting protocols promote greater surface roughness.

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This study focused on evaluating the sensitivity and limitations of the simplified equipment used in the Digital Image Correlation (DIC) technique, comparing them with the analog extensometer, based on the mechanical property data of a composite made of fiberglass and epoxy resin. The objectives included establishing a methodology based on the literature, fabricating samples through manual lamination, conducting mechanical tests according to the ASTM D3039 and D3518 standards, comparing DIC with the analog extensometer of the testing machine, and contrasting the experimental results with classical laminate theory. Three composite plates with specific stacking sequences ([0]3, [90]4, and [±45]3) were fabricated, and samples were extracted for testing to determine tensile strength, modulus of elasticity, and other properties. DIC was used to capture deformation fields during testing. Comparisons between data obtained from the analog extensometer and DIC revealed differences of 11.1% for the longitudinal modulus of elasticity E1 and 5.6% for E2. Under low deformation conditions, DIC showed lower efficiency due to equipment limitations. Finally, a theoretical analysis based on classical laminate theory, conducted using a Python script, estimated the longitudinal modulus of elasticity Ex and the shear strength of the [±45]3 laminate, highlighting a relative difference of 31.2% between the theoretical value of 7136 MPa and the experimental value of 5208 MPa for Ex.

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O selamento dentinário imediato é um procedimento essencial na Odontologia, que envolve a aplicação de agentes de selamento na interface entre a dentina e o material restaurador imediatamente após a remoção da cárie e do preparo da cavidade dentária. Este processo busca selar os túbulos dentinários expostos, proporcionando proteção à polpa dentária. O presente caso foi realizado em um paciente do sexo masculino, 56 anos que se queixou de desconforto no elemento dentário 17. Após avaliação clínica e radiográfica, foi constatado uma ampla restauração desadaptada na porção mesio - oclusal do referido dente, sendo que o elemento em questão não possui tratamento endodôntico. Após planejamento e assinatura do TCLE, os seguintes passos foram realizados: remoção da lesão cariosa do dente 17, seguido da realização do levantamento marginal mesial e a realização do selamento dentinário imediato. Moldagem com silicone de adição do dente em questão e do antagonista, assim como registro da mordida. Foi confeccionada uma restauração semidireta em resina composta sob o modelo de gesso obtido. A cimentação da restauração foi feita na consulta seguinte, cumprindo os requisitos fundamentais para restaurar forma, função e estética, resultando na melhoria da qualidade de vida do paciente(AU)

Immediate dentin sealing is an essential procedure in dentistry, involving the application of sealing agents at the interface between dentin and the restorative material immediately after caries removal and cavity preparation. This process aims to seal exposed dentinal tubules, providing protection to the dental pulp. The present case involved a 56-year-old male patient who complained of discomfort in tooth number 17. After clinical and radiographic evaluation, a wide, maladapted restoration in the mesio-occlusal portion of the tooth was identified, with no endodontic treatment in the affected element. Following planning and informed consent, the following steps were taken: removal of the carious lesion from tooth number 17, followed by the execution of mesial marginal elevation and immediate dentin sealing. Silicone addition molding of the affected tooth and antagonist, along with bite registration, was performed. A semi-direct restoration in composite resin was fabricated based on the obtained gypsum model. The restoration was cemented in the subsequent appointment, meeting the essential requirements to restore form, function, and aesthetics, resulting in an improvement in the patient's quality of life(AU)

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Restaurações diretas em resina composta são amplamente utilizadas em odontologia para restaurar dentes posteriores. Todavia, quando há grande destruição coronária, onde a distância do istmo excede dois terços da distância intercuspídea, as restaurações indiretas em resina composta são indicadas. O presente estudo teve como objetivo relatar a análise de um prontuário de um paciente que recebeu uma restauração indireta em resina composta em dente posterior amplamente destruído. Através da análise de prontuários de pacientes atendidos nas disciplinas de Estágios Supervisionados do Curso de Odontologia da FSG Centro Universitário no ano de 2023, foi selecionado um prontuário de um paciente que compareceu a clínica odontológica da FSG com uma restauração em amálgama fraturada com reparo em resina composta que apresentou sintomatologia dolorosa. O procedimento diagnóstico ocorreu através de exame clínico e radiográfico, que constatou a indicação de substituição da restauração insatisfatória e realização de uma restauração indireta em resina composta. Os resultados estéticos e funcionais apresentados demostraram a viabilidade da técnica restauradora indireta em resina composta para reabilitar dentes posteriores com ampla destruição coronária(AU)

Direct composite resin restoration are widely used in dentistry to restore posterior teeth. However, when there is large coronary destruction, that the distance from the isthmus exceeds two- thirds of the intercuspal distance, indirect composite resin restorations are indicated. This study aimed to report the analysis of a dental record of a patient who received an indirect restoration in composite resin in a badly destroyed posterior tooth. Through the analysis of dental records of patients seen in the disciplines of Supervised Internship of the Dentistry Course at FSG Centro Universitário in the year 2023, the dental record of a patient who attended the FSG dental clinic with fractured amalgam restoration with composite resin repair was selected who had painful symptoms. The diagnostic procedure took place through clinical and radiographic examination, which revealed the indication of replacing the unsatisfactory restoration and carrying out an indirect restoration in composite resin.The aesthetic and functional results presented demonstrated the viability of the indirect composite resin restoration technique for rehabilitating posterior teeth with extensive coronal destruction(AU)

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A escolha da técnica restauradora desempenha papel fundamental na eficácia e duração de um tratamento reabilitador. O objetivo deste relato de caso foi descrever a utilização da técnica semidireta para a confecção de uma restauração em resina composta em um primeiro molar inferior. A paciente apresentava uma restauração insatisfatória no dente 36, que necessitava ser substituída devido à infiltração por cárie. Optou-se pela técnica semidireta devido à amplitude da cavidade, que envolvia estruturas de suporte, e pela combinação das vantagens das abordagens direta e indireta. O procedimento envolveu a remoção de tecido cariado, a aplicação de hidróxido de cálcio pasta, seguida da aplicação de uma fina camada de ionômero de vidro e, posteriormente, resina fluída para realizar o selamento dentinário. O preparo foi realizado seguindo os princípios necessários. O elemento em questão foi moldado com silicone de adição e o arco antagonista, com alginato. Ambos modelos foram vertidos com silicone para modelos semirrígidos e montados em oclusor de peças de brinquedo. A restauração semidireta foi confeccionada em resina composta Filtek Z350 XT, respeitando a anatomia do dente 36. Pigmentos foram utilizados para aprimorar detalhes estéticos. Após acabamento e polimento, a peça foi condicionada e cimentada com cimento dual Relyx Ultimate. Pode-se concluir que a abordagem restauradora por meio da técnica semidireta construída em modelo semirrígido é uma opção terapêutica conservadora e vantajosa para dentes com extensa destruição coronária. Essa técnica possibilita a restauração de forma eficaz, garantindo tanto a estética quanto a função adequada do dente afetado(AU)

The choice of restorative technique plays a fundamental role in the effectiveness and duration of rehabilitation treatment. The objective of this case report was to describe the use of the semi-direct technique to create a composite resin restoration in a lower first molar. The patient had an unsatisfactory restoration on tooth 36, which needed to be replaced due to cavity infiltration. The semi-direct technique was chosen due to the amplitude of the cavity, which involved support structures, and the combination of advantages of the direct and indirect approaches. The procedure involved the removal of carious tissue, and the application of calcium hydroxide paste, followed by the application of a thin layer of glass ionomer and, subsequently, fluid resin to seal the dentin. The preparation was carried out following the necessary principles. The element in question was molded with addition silicone and the antagonist arch was molded with alginate. Both models were poured with silicone for semi-rigid models and mounted on toy parts occluders. The semi-direct restoration was made in Filtek Z350 XT composite resin, respecting the anatomy of tooth 36. Pigments were used to improve aesthetic details. After finishing and polishing, the piece was conditioned and cemented with Relyx Ultimate dual cement. It can be concluded that the restorative approach using the semi-direct technique built on a semi-rigid model is a conservative and advantageous therapeutic option for teeth with extensive coronal destruction. This technique allows for effective restoration, ensuring both the aesthetics and adequate function of the affected tooth(AU)

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OBJECTIVE: To evaluate experimental dimethacrylate-based materials containing calcium orthophosphates or calcium silicate particles in terms of their optical, mechanical and Ca2+ release behaviour. METHODS: Dicalcium phosphate dihydrate (DCPD), hydroxyapatite (HAp), beta-tricalcium phosphate (ß-TCP) or calcium silicate (CaSi) particles were added to a photocurable BisGMA/TEGDMA resin (1:1 in mols) at a 30 vol% fraction. Materials containing silanized or non-silanized barium glass particles were used as controls. Degree of conversion (DC) at the top and base of 2-mm thick specimens was determined by ATR-FTIR spectroscopy (n = 5). Translucency parameter (TP) and transmittance (%T) were determined using a spectrophotometer (n = 3). Biaxial flexural strength (BFS) and flexural modulus (FM) were determined by biaxial flexural testing after 24 h storage in water (n = 10). Ca2+ release in water was determined during 28 days by inductively coupled plasma optical emission spectrometry (n = 3). Statistical analysis was performed using ANOVA/Tukey test (DC: two-way; TP, %T; BFS and FM: one-way; Ca2+ release: repeated measures two-way, α = 5 %). RESULTS: CaSi and ß-TCP particles drastically reduced DC at 2 mm, TP and %T (p < 0.001). Compared to both controls, all Ca2+-releasing materials presented lower BFS (p < 0.001) and only the material with DCPD showed significantly lower FM (p < 0.05). The material containing CaSi presented the highest Ca2+ release, while among materials formulated with calcium orthophosphates the use of DCPD resulted in the highest release (p < 0.001). SIGNIFICANCE: CaSi particles allowed the highest Ca2+ release. Notwithstanding, the use of DCPD resulted in a material with the best compromise between optical behaviour, DC, strength and Ca2+ release.

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To evaluate the microstructural characterization, mechanical properties and antimicrobial activity of acrylic resins incorporated with different concentrations of reduced graphene oxide (rGO). Specimens were made of self-cured and heat-cured acrylic resins for the control group and concentrations of 0.5%, 1%, and 3%. The microstructural characterization was evaluated by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDS). For mechanical testing, flexural strength, and Knoop hardness tests were performed. Microbiological evaluations were performed by colony forming units (CFU) analysis, tetrazolium salt reduction (XTT), and SEM images. The modified acrylic resins showed increased mechanical properties at low concentrations (p < 0.05) and with reduced S. mutans (p < 0.05). Reduced graphene oxide interfered with the mechanical performance and microbiological properties of acrylic resins depending on the concentration of rGO, and type of polymerization and microorganism evaluated. The incorporation of graphene compounds into acrylic resins is an alternative to improve the antimicrobial efficacy and performance of the material.

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The present study examined different concentrations of the butylated hydroxytoluene (BHT) inhibitor on the kinetics of conversion, polymerization shrinkage stress, and other correlated physicochemical properties of experimental resin composites (ERC). A model composite was formulated with 75 wt% filler containing 0.5 wt% camphorquinone and 1 wt% amine with BHT concentrations of 0.01 wt% (BHT-0.01); 0.1 wt% (BHT-0.1); 0.25 wt% (BHT-0.25); 0.5 wt% (BHT-0.5); 1 wt% (BHT-1), and control (no BHT). They were tested on polymerization shrinkage stress (PSS; n = 5), degree of conversion (DC; n = 3), maximum polymerization rate (RpMAX; n = 5), water sorption (Wsp; n = 0), and solubility (Wsl; n = 10), flexural strength (FS; n = 10), flexural modulus (FM; n = 10), Knoop microhardness (KH; n = 10), and microhardness reduction (HR; n = 10). Data concerning these tests were submitted to one-way ANOVA and Tukey's test (α = 0.05; ß = 0.2). BHT-0.25, BHT-0.5, and BHT-1 showed a gradually significant decrease in PSS (p = 0.037); however, BHT-1 demonstrated a decrease in the physicochemical properties tested. Thus, within the limitations of this study, it was possible to conclude that BHT concentrations between 0.25 and 0.5 wt% are optimal for reducing shrinkage stress without affecting other physicochemical properties of ERCs.

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