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1.
Bol. latinoam. Caribe plantas med. aromát ; 19(3): 321-333, mayo 2020. ilus, tab
Article in English | LILACS | ID: biblio-1116432

ABSTRACT

In this study the in vitro investigation of the inhibitory effect of ethanol extract of Viburnum opulus L. bark sample on Streptococcus mutans planctonic cells and biofilm has been intended. A Scanning electron microscopy analysis has been performed in order to investigate the inhibitory effect of the extract on Streptococcus mutans biofilms. Furthermore, the Exopolysaccharide and dextran production of this bacteria have been identified in the presence of the extract. It has been found out that the bark extract with the concentration of 2,5 mg/mL is able to inhibit more than 50% of the cells in the different times development phases. According to this, the exopolymeric matrix on the biofilm surface disperses and the Exopolysaccharide and dextran production get lowered in the presence of bark extract compared to the control group. It is considered that this extract can be used as an alternative approach for the new chemotherapeutic strategies against tooth decay.


En este estudio se investigó el efecto inhibitorio in vitro del extracto de etanólico de una muestra de corteza de Viburnum opulus L. en biopelículas de células planctónicas de Streptococcus mutans. Se realizó un análisis de microscopía electrónica de barrido para investigar el efecto inhibitorio del extracto sobre las biopelículas de Streptococcus mutans. Además, se identificó la producción de exopolisacárido y dextrano de esta bacteria en presencia del extracto. Se descubrió que el extracto de corteza con una concentración de 2,5 mg/ml inhibió más del 50% de las células en las diferentes fases de desarrollo. Consecuentemente, la matriz exopolimérica en la superficie de la biopelícula se dispersa y la producción de exopolisacárido y dextrano se reduce en presencia de extracto de corteza en comparación con el grupo de control. Se sugiere que este extracto puede ser usado como un enfoque alternativo para las nuevas estrategias quimioterapéuticas contra la carie dental.


Subject(s)
Streptococcus mutans/drug effects , Plant Extracts/pharmacology , Viburnum opulus/pharmacology , Viburnum/chemistry , Polysaccharides, Bacterial/analysis , Streptococcus mutans/metabolism , In Vitro Techniques , Microscopy, Electron, Scanning , Dextrans/analysis , Biofilms/drug effects , Ethanol , Biofouling
2.
Bol. latinoam. Caribe plantas med. aromát ; 19(1): 65-76, ene. 2020. tab, ilus
Article in English | LILACS | ID: biblio-1102867

ABSTRACT

Due to the biological activities of Syzygium aromaticum essential oil, its incorporation in methacrylate polymeric (Eudragit E100) nanoparticles (NP), physical characterization, and antimicrobial essays were evaluated. The clove bears great potential for applications in dentistry. The oil was obtained by hydrodistillation and oil loaded NP using the nanoprecipitation method. Particle size and polydispersity index were determined by photon correlation spectroscopy, and physical morphology by electron microscopy. Loading capacity and in vitro eugenol release were evaluated by gas mass chromatography, and the antimicrobial activity of oil loaded-NP was calculated against Streptococcus mutans. Different chemical ingredients were characterized, and eugenol was the principal compound with 51.55%. Polymer content was directly related to NP homogenous size, which was around 150 nm with spherical morphology. A 73.2% loading capacity of eugenol was obtained. Oil loaded NP presented a fickian-type release mechanism of eugenol. Antimicrobial activity to 300 µg/mL was obtained after 24 h.


Debido a las actividades biológicas del aceite esencial de Syzygium aromaticum, se evaluó su incorporación en nanopartículas (NP) de metacrilato polimérico (Eudragit E100), su caracterización y ensayos antimicrobianos. El clavo tiene un gran potencial para aplicaciones en odontología. El aceite se obtuvo por hidrodestilación y las NP cargado de aceite utilizando el método de nanoprecipitación. El tamaño de partícula y el índice de polidispersidad se determinaron mediante espectroscopia de correlación fotónica y su morfología por microscopía electrónica. La capacidad de carga y la liberación de eugenol in vitro se evaluaron mediante cromatografía de gases en masa, y la actividad antimicrobiana se evaluó contra Streptococcus mutans. Se caracterizaron diferentes ingredientes químicos, siendo el eugenol el principal compuesto con 51.55%. El contenido de polímero se relacionó directamente con el tamaño homogéneo de NP, que fue de alrededor de 150 nm con morfología esférica. Se obtuvo un 73,2% de capacidad de carga de eugenol. El aceite cargado en NP presentó un mecanismo de liberación de eugenol de tipo fickiano. La actividad antimicrobiana a 300 µg/mL se obtuvo después de 24 h.


Subject(s)
Polymers/chemistry , Oils, Volatile/administration & dosage , Syzygium/chemistry , Nanoparticles/chemistry , Anti-Bacterial Agents/administration & dosage , Streptococcus mutans/drug effects , Eugenol/pharmacology , Oils, Volatile/pharmacology , Administration, Oral , Chromatography, Thin Layer , Drug Delivery Systems , Gas Chromatography-Mass Spectrometry , Anti-Bacterial Agents/pharmacology
3.
Braz. arch. biol. technol ; 63: e20190339, 2020. graf
Article in English | LILACS | ID: biblio-1132187

ABSTRACT

Abstract Conventional orthodontic treatment with the use of stainless steel may be detrimental to oral health by promoting demineralizing lesions appearance and increasing adhesion and formation of bacterial biofilm, inducing the development of cavities. An alternative that has been researched to reduce the side effects of orthodontic treatment is the coating of materials with antimicrobial nanoparticles. Nanometric- sized particles increase their surface area and contact with the microbial membrane, consequently intensifying their bacteriostatic and bactericidal effect. In this work, hydrothermal synthesis, a "green" process was used to attach silver nanoparticles (AgNPs) to the surface of two different brands of orthodontic wires. The coated materials were analyzed for their physicochemical properties by scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC), which showed the distribution of AgNPs along the wires without modifying their properties. In the microbiological test, one of the brands showed a statistically significant difference in microbial adhesion and biofilm formation by Staphylococcus aureus and Streptococcus mutans. Results lead to the conclusion that antimicrobial orthodontic wires coated with silver nanoparticles through hydrothermal synthesis is a promising material for the improvement of orthodontic treatment.


Subject(s)
Orthodontic Wires , Staphylococcus aureus/drug effects , Streptococcus mutans/drug effects , Metal Nanoparticles , Anti-Bacterial Agents/pharmacology , Silver , Bacterial Adhesion , Calorimetry , Microscopy, Electron, Scanning , Dental Plaque , Linings
4.
Rev. ADM ; 76(2): 77-80, mar.-abr. 2019. ilus, tab
Article in Spanish | LILACS | ID: biblio-1005030

ABSTRACT

La OMS y la FDI han publicado que entre el 60 y 90% de los escolares padecen caries. En nuestro país, el Sistema de Vigilancia Epidemiológica de Patologías Orales (SIVEPAB) 2012, reporta un 85% de caries a nivel nacional en población pediátrica. Los agentes anticariogénicos como el diamino y el fluoruro de plata son un tratamiento alentador, este agente puede actuar como bactericida o bacteriostático en función de su concentración y su capacidad para inhibir el crecimiento de estreptococos del grupo viridans, y por ende, de la caries. Problema: ¿Cuál es la efectividad bactericida del diamino fluoruro de plata (Saforide®) a diferente concentración sobre la microbiota cariogénica de escolares? Objetivo: Determinar la eficacia bactericida del diamino fluoruro de plata (DFP) a diferentes concentraciones en el crecimiento bacteriano de Streptococcus mitis, S. mutans y S. salivarius en muestras de saliva y dentina en escolares. Material y métodos: Se llevó a cabo un estudio experimental con una variable independiente, el efecto bactericida del diamino fluoruro de plata y se tomó el halo de inhibición como la dependiente. Se utilizaron medidas descriptivas como prueba de comparación y análisis de varianza usando post-hoc Tukey≠ con una confianza del 95%, y análisis de datos exploratorios. Resultados: Se analizaron 100 muestras, de las cuales 48.3% correspondió a S. mutans, 41.4% a S. salivarius y 10.3% a S. mitis, se obtuvo una mayor zona de inhibición para las tres bacterias al 38% mostrando una diferencia estadísticamente significativa 12% (p < 0.05). También se observó un efecto bacteriostático al 12%, no así para el 38%, donde se encontró un efecto bactericida Conclusión: Nuestros resultados sugieren que al 38% de la concentración hay un claro efecto bactericida en el grupo de estreptococos viridans y el 12% no se recomienda para la detención de caries debido al efecto bacteriostático (AU)


WHO and FDI have ruled that 60-90% of schoolchildren are affected by caries. In our country, the System of Epidemiological Surveillance of Oral Pathologies (SIVEPAB) (SIVEPAB) 2012. Report a rate of 85% of caries nationally in pediatric population. Anticariogenic diamino agents such as silver fluoride are an encouraging decrease in treatment for these high rates of tooth decay in our country, this agent can act as bactericidal or bacteriostatic based on their concentration and their ability to inhibit endogenous metalloproteinase (MMP-2, 8, 9). Problem: What will be the bactericidal effectiveness of silver diamine fluoride different concentration on cariogenic Streptococci saliva samples taken from school and dentin? Objective: Determine the bactericidal effectiveness Silver diamine fluoride (SDF) to different concentration on bacterial growth of Streptococcus mitis, S. mutans, and S. salivarius in saliva samples and dentin in school. Material and methods: An experimental study was conducted as an independent variable the bactericidal effect of silver diamine fluoride was taken as dependent inhibition halo. Descriptive measures were used as a comparison test and analysis of variance using Post-hoc Tukey with 95% confidence, and exploratory data analysis. Results: One hundred samples, of which 48.3% corresponded to S. mutans, 41.4% to S. salivarius and 10.3% to S. mitis, were analyzed, we obtained a larger zone of inhibition for all three organisms at 38% showing a statistically significant difference from 12% (p < 0.05). It was also observed that the 12% sample bacteriostatic effect, not to the concentration of 38% was found a bactericidal effect. Conclusion: Our results suggest that 38% concentration has a bactericidal effect on Streptococcus viridans group and 12% showed not recommended for the arrest or detention of dentine caries bacteriostatic effect (AU)


Subject(s)
Humans , Male , Female , Child, Preschool , School Dentistry , Streptococcus mutans/drug effects , Cariostatic Agents/therapeutic use , Fluorides, Topical/therapeutic use , Dental Caries/prevention & control , Saliva/microbiology , Analysis of Variance , Treatment Outcome , Silver Compounds/therapeutic use , Culture Media , Dentin/microbiology , Mexico
5.
J. appl. oral sci ; 27: e20180514, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-1012510

ABSTRACT

Abstract Objectives: The aim of this study was to assess the effect of Myracrodruon urundeuva All. and Qualea grandiflora Mart. leaves hydroalcoholic extracts on viability and metabolism of a microcosm biofilm and on enamel demineralization prevention. Methodology: Microcosm biofilm was produced on bovine enamel using inoculum from pooled human saliva mixed with McBain saliva, under 0.2% sucrose exposure, for 14 days. The biofilm was daily-treated with the extracts for 1 min. At the end, it was analyzed with respect to viability by fluorescence, CFU counting and extracellular polysaccharides (phenol-sulphuric acid colorimetric assay) and lactic acid (enzymatic assay) production. The demineralization was measured by TMR. The data were compared using ANOVA or Kruskal-Wallis (p<0.05). Results: M. urundeuva All. at 100, 10 and 0.1 μg/mL and Q. grandiflora Mart. at 100 and 0.1 μg/mL reduced biofilm viability similarly to positive control (chlorhexidine) and significantly more than the negative-vehicle control (35% ethanol). M. urundeuva at 1000, 100 and 0.1 μg/mL were able to reduce both lactobacilli and mutans streptococci CFU counting, while Q. grandiflora (1000 and 1.0 μg/mL) significantly reduced mutans streptococci CFU counting. On the other hand, the natural extracts were unable to significantly reduce extracellular polysaccharides and lactic acid productions neither the development of enamel carious lesions. Conclusions: The extracts showed antimicrobial properties on microcosm biofilm, however, they had no effect on biofilm metabolism and caries protection.


Subject(s)
Animals , Male , Cattle , Plant Extracts/pharmacology , Tooth Demineralization/prevention & control , Biofilms/drug effects , Anacardiaceae/chemistry , Myrtales/chemistry , Anti-Infective Agents/pharmacology , Polysaccharides, Bacterial/metabolism , Saliva/chemistry , Streptococcus mutans/drug effects , Microradiography/methods , Colony Count, Microbial , Cariostatic Agents/pharmacology , Microbial Sensitivity Tests , Reproducibility of Results , Plant Leaves/chemistry , Lactic Acid/metabolism , Dental Enamel/drug effects , Dental Enamel/microbiology , Microbial Viability/drug effects , Lactobacillus/drug effects
6.
J. appl. oral sci ; 27: e20180042, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-975890

ABSTRACT

Abstract The use of antimicrobial agents is an efficient method to prevent dental caries. Also, nanometric antibacterial agents with wide antibacterial spectrum and strong antibacterial effects can be applied for prevention of dental caries. Objectives: The aim of this study was to evaluate the inhibitory effect of reduced graphene oxide-silver nanoparticles (rGO/Ag) composite on the progression of artificial enamel caries in a Streptococcus mutans biofilm model. Material and Methods: Enamel specimens from bovine incisors were divided into eight treatment groups (n = 13), as follows: group 1 was inoculated with S. mutans grown in Brain Heart Infusion containing 1% sucrose (1% BHIS), as negative control; groups 2-4 were inoculated with S. mutans grown in the presence of different rGO/Ag concentrations (0.08, 0.12, 0.16 mg/mL) + 1% BHIS; group 5-7 were inoculated with S. mutans grown in the presence of different agents (0.16 mg/mL reduced graphene oxide, 0.16 mg/mL silver nanoparticles, 10 ppm NaF) + 1% BHIS; group 8 was mixed with 1% BHIS, without inoculation. Artificial enamel carious lesions were produced by S. mutans biofilm model for 7 days. Confocal laser scanning microscopy and atomic force microscopy were used to analyze roughness and morphology of the enamel surface. Polarized light microscopy and confocal laser scanning microscopy were employed to measure the lesion depth and the relative optical density (ROD) of the demineralized layer. Results: Compared with the control groups, the rGO/Ag groups showed: (a) reduced enamel surface roughness; (b) much smoother and less eroded surfaces; (c) shallower lesion depth and less mineral loss. Conclusion: As a novel composite material, rGO/Ag can be a promising antibacterial agent for caries prevention.


Subject(s)
Animals , Cattle , Silver/pharmacology , Streptococcus mutans/drug effects , Dental Caries/prevention & control , Dental Enamel/drug effects , Metal Nanoparticles/chemistry , Graphite/pharmacology , Anti-Bacterial Agents/pharmacology , Reference Values , Silver/chemistry , Surface Properties , Cariostatic Agents/pharmacology , Reproducibility of Results , Microscopy, Confocal , Disease Progression , Dental Caries/microbiology , Dental Enamel/microbiology , Nanocomposites/chemistry , Graphite/chemistry
7.
J. appl. oral sci ; 27: e20180183, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-975880

ABSTRACT

Abstract Objectives: This study investigated the physical and mechanical properties, antibacterial effect and biocompatibility of novel elastomeric temporary resin-based filling materials (TFMs) containing zinc methacrylate (ZM). Material and Methods: Experimental TFMs were prepared by mixing the zinc methacrylate with monomer, co-monomer, photoinitiator and fillers. A ZM concentration of 0 (control), 0.5% (Z0.5); 1% (Z1), 2% (Z2), or 5% (ZM5) wt% was added to the TFMs. Fermit-N (F) was used for comparison with the experimental material. Microleakage, water sorption/solubility, degree of conversion, depth of cure, ultimate tensile strength, and hardness were determined and compared. A modified direct contact test (DCT) with Enterococcus faecalis and a Streptococcus mutans' biofilm accumulation assay was carried out to evaluate the antimicrobial effect and cytotoxicity of the assay. Statistical comparisons were performed (α=5%). Results: The results showed that the physical and mechanical properties of the experimental TFMs with ZM are comparable with the properties of the commercial reference and some properties were improved, such as lower microleakage and water sorption, and higher ultimate tensile strength values. TFMs with ZM killed E. faecalis only after 1 h. Biofilm development of S. mutans was not affected by the inclusion of ZM in the experimental TFMs. Conclusions: The present findings suggest that the physical, mechanical and biological properties of the experimental TFMs with ZM are comparable with the properties of the commercial reference. However, some properties were improved, such as lower microleakage and water sorption, and higher ultimate tensile strength values.


Subject(s)
Animals , Cattle , Zinc/chemistry , Composite Resins/chemistry , Elastomers/chemistry , Dental Restoration, Temporary/methods , Methacrylates/chemistry , Reference Values , Solubility , Streptococcus mutans/drug effects , Tensile Strength , Time Factors , Zinc/pharmacology , Materials Testing , Colony Count, Microbial , Random Allocation , Reproducibility of Results , Enterococcus faecalis/drug effects , Composite Resins/pharmacology , Elastomers/pharmacology , Dental Leakage , Hardness Tests , Methacrylates/pharmacology , Anti-Bacterial Agents/pharmacology
8.
Braz. oral res. (Online) ; 33: e075, 2019. tab, graf
Article in English | LILACS | ID: biblio-1019599

ABSTRACT

Abstract Resinous infiltrants are indicated in the treatment of incipient carious lesions, and further development of these materials may contribute to greater control of these lesions. The aim of this study was to analyze the physical and antibacterial properties of experimental infiltrants containing iodonium salt and chitosan. Nine experimental infiltrants were formulated by varying the concentration of the diphenyliodonium salt (DPI) at 0, 0.5 and 1 mol%; and chitosan at 0, 0.12 and 0.25 g%. The infiltrants contained the monomeric base of triethylene glycol dimethacrylate and bisphenol-A dimethacrylate ethoxylate in a 75 and 25% proportion by weight, respectively; 0.5 mol% camphorquinone and 1 mol% ethyl 4-dimethylaminobenzoate. The degree of conversion was evaluated using Fourier transformer infrared spectroscopy, and the flexural strength and elastic modulus using the three-point bending test. Sorption and solubility in water, and antibacterial analysis (minimum inhibitory concentration and minimum bactericidal concentration) were also analyzed. Data was analyzed statistically by two-way ANOVA and Tukey's test (p<0.05), with the exception of the antibacterial test, which was evaluated by visual inspection. In general, the infiltrant group containing 0.5% DPI and 0.12% chitosan showed high values of degree of conversion, higher values of elastic modulus and flexural strength, and lower sorption values in relation to the other groups. Antibacterial activity was observed in all the groups with DPI, regardless of the concentration of chitosan. The addition of DPI and chitosan to experimental infiltrants represents a valid option for producing infiltrants with desirable physical and antibacterial characteristics.


Subject(s)
Polyethylene Glycols/chemistry , Polymethacrylic Acids/chemistry , Salts/chemistry , Composite Resins/chemistry , Chitosan/chemistry , Elastic Modulus , Methacrylates/chemistry , Anti-Bacterial Agents/chemistry , Polyethylene Glycols/pharmacology , Polymethacrylic Acids/pharmacology , Reference Values , Salts/pharmacology , Solubility , Streptococcus mutans/drug effects , Materials Testing , Microbial Sensitivity Tests , Reproducibility of Results , Analysis of Variance , Statistics, Nonparametric , Composite Resins/pharmacology , Chitosan/pharmacology , Light-Curing of Dental Adhesives , Flexural Strength , Lactobacillus acidophilus/drug effects , Methacrylates/pharmacology , Anti-Bacterial Agents/pharmacology
9.
Braz. oral res. (Online) ; 33: e019, 2019. tab, graf
Article in English | LILACS | ID: biblio-989473

ABSTRACT

Abstract The aim of this study was to evaluate the influence of polyhexamethylene guanidine hydrochloride (PHMGH) in the physico-chemical properties and antibacterial activity of an experimental resin sealant. An experimental resin sealant was formulated with 60 wt.% of bisphenol A glycol dimethacrylate and 40 wt.% of triethylene glycol dimethacrylate with a photoinitiator/co-initiator system. PHMGH was added at 0.5 (G0.5%), 1 (G1%), and 2 (G2%) wt.% and one group remained without PHMGH, used as control (GCTRL). The resin sealants were analyzed for degree of conversion (DC), Knoop hardness (KHN), and softening in solvent (ΔKHN), ultimate tensile strength (UTS), contact angle (θ) with water or α-bromonaphthalene, surface free energy (SFE), and antibacterial activity against Streptococcus mutans for biofilm formation and planktonic bacteria. There was no significant difference for DC (p > 0.05). The initial Knoop hardness ranged from 17.30 (±0.50) to 19.50 (± 0.45), with lower value for GCTRL (p < 0.05). All groups presented lower KHN after immersion in solvent (p < 0.05). The ΔKHN ranged from 47.22 (± 4.30) to 57.22 (± 5.42)%, without significant difference (p > 0.05). The UTS ranged from 54.72 (± 11.05) MPa to 60.46 (± 6.50) MPa, with lower value for G2% (p < 0.05). PHMGH groups presented no significant difference compared to GCTRL in θ (p > 0.05). G2% showed no difference in SFE compared to GCTRL (p > 0.05). The groups with PHMGH presented antibacterial activity against biofilm and planktonic bacteria, with higher antibacterial activity for higher PHMGH incorporation (p < 0.05). PHMGH provided antibacterial activity for all resin sealant groups and the addition up to 1 wt.% showed reliable physico-chemical properties, maintaining the caries-protective effect of the resin sealant over time.


Subject(s)
Humans , Streptococcus mutans/drug effects , Biofilms/drug effects , Dental Materials/chemistry , Guanidines/pharmacology , Anti-Bacterial Agents/pharmacology , Materials Testing , Biofilms/growth & development , Dental Materials/pharmacology , Guanidines/chemistry , Anti-Bacterial Agents/chemistry
10.
J. appl. oral sci ; 27: e20180663, 2019. tab, graf
Article in English | LILACS, BBO | ID: biblio-1040224

ABSTRACT

Abstract Objective: To investigate the use of polymethyl methacrylate (PMMA) electrospun fiber mats containing different amounts of polyethylene oxide (PEO) as a doxycycline delivery system and to test antibacterial activity against an oral pathogen. Methodology: PMMA powders or PEO (mol wt 200 Kd) (10,20,30% w/w/) were dissolved in N, N-dimethylformamide (DMF) to obtain a final polymer concentration of 15% in DMF (w/v). 2% Doxycycline monohydrate was added to the solutions and submitted to vortex mixing. The solution was transferred to a plastic syringe and fit into a nanofiber electrospinning unit. The parameters applied were: voltage at 17.2 kV; distance of 20 cm between the needle tip and the collector plate; target speed at 2 m/min; and transverse speed at 1cm/min. Syringe pump speed was 0.15 mm/min. The drug release analysis was performed by removing aliquots of the drug-containing solution (in PBS) at specific periods. Doxycycline release was quantified using RP-HPLC. Fiber mats from all groups had their antibacterial action tested against S. mutans based on inhibition halos formed around the specimens. The experiments were performed in triplicate. Gravimetric analysis at specific periods was performed to determine any polymer loss. Morphological characterization of the electrospun fibers was completed under an optical microscope followed by SEM analysis. Results: The addition of PEO to the PMMA fibers did not affect the appearance and diameter of fibers. However, increasing the %PEO caused higher doxycycline release in the first 24 h. Fibers containing 30% PEO showed statistically significant higher release when compared with the other groups. Doxycycline released from the fibers containing 20% or 30% of PEO showed effective against S. mutans. Conclusion: The incorporation of PEO at 20% and 30% into PMMA fiber mat resulted in effective drug release systems, with detected antibacterial activity against S. mutans.


Subject(s)
Polyethylene Glycols/pharmacokinetics , Doxycycline/pharmacokinetics , Polymethyl Methacrylate/pharmacokinetics , Nanofibers/chemistry , Anti-Bacterial Agents/pharmacokinetics , Polyethylene Glycols/chemistry , Streptococcus mutans/drug effects , Time Factors , Water/chemistry , Microscopy, Electron, Scanning , Reproducibility of Results , Analysis of Variance , Chromatography, High Pressure Liquid/methods , Doxycycline/chemistry , Polymethyl Methacrylate/chemistry , Immersion , Anti-Bacterial Agents/chemistry , Molecular Weight
11.
J. appl. oral sci ; 27: e20180262, 2019. tab
Article in English | LILACS, BBO | ID: biblio-1019969

ABSTRACT

Abstract The incorporation of antimicrobials in the composites as an attempt to reduce bacterial adhesion without jeopardizing mechanical properties is a challenge for Dentistry. Objective: To evaluate the bacterial adhesion and physical properties of a composite containing the methacrylate triclosan- derivative monomer (TM). Methodology: TM was synthesized and added to an experimental composite. Samples were divided into two groups: Control and TM (13.4 wt%). Antibacterial Activity: Three specimens of each material were prepared and placed on bacterial suspensions of Streptococcus mutans for 1, 5 and 10 days. After these periods the counting of the colonies (log10) was performed. Assays was performed in triplicate. Physical Properties: Three-body Abrasion (TBA): Ten specimens of each material were prepared and stored at 37°C/24 h. The surface roughness (Ra) and hardness (KHN) were analyzed. Next, the specimens were submitted to abrasive wear (30,000 cycles) and re-evaluated for Ra and KHN; Sorption/solubility (SS): cylindrical specimens (n=10) were prepared and weighted. The specimens were immersed in deionized water for 7 days at 37°C and then their weight was verified again. SS were calculated using accepted formulas; Diametral tensile strength (DTS): specimens (n=10) underwent test performed in an Instron universal testing machine at a crosshead speed of 1 mm/min. Data were submitted to appropriate statistical tests according to data distribution and assay (p<0.05). Results: Bacterial Adhesion: TM showed a significant reduction on biofilm accumulation in the evaluated periods: 1 day (1.537±0.146); 5 days (2.183±0.138) and 10 days (4.469±0.155) when compared with Control: 1 day (4.954±0.249); 5 days (5.498±0.257) and 10 days (6.306±0.287). Physical Properties: For TBA, SS and DTS no significant difference was found between groups Control and TM. The incorporation of methacrylate triclosan-based monomer in the experimental composite reduce bacterial adhesion of S. mutans and did not affect important polymer properties.


Subject(s)
Triclosan/chemistry , Composite Resins/chemistry , Methacrylates/chemistry , Anti-Bacterial Agents/chemistry , Reference Values , Solubility , Streptococcus mutans/drug effects , Surface Properties , Tensile Strength , Time Factors , Toothbrushing , Triclosan/pharmacology , Bacterial Adhesion/drug effects , Materials Testing , Colony Count, Microbial , Reproducibility of Results , Composite Resins/pharmacology , Hardness Tests , Methacrylates/pharmacology , Anti-Bacterial Agents/pharmacology
12.
Braz. dent. j ; 29(4): 354-358, July-Aug. 2018. tab, graf
Article in English | LILACS | ID: biblio-974160

ABSTRACT

Abstract This study aimed to evaluate in vitro the antimicrobial effect of a bioadhesive chitosan-based oral membrane with chlorhexidine for local treatment of infections in the oral tissues. Five oral membranes of different compositions were tested: 5% chitosan (G1); 5% chitosan ± 0.2% chlorhexidine (G2), 5% chitosan ± 0.6% chlorhexidine (G3), 5% chitosan ± 1.0% chlorhexidine (G4), and 5% chitosan ± 2.0% chlorhexidine (G5). Also, five gel types were tested according to the following compositions: 5% chitosan gel (G6), 0.2% chlorhexidine gel (G7), 2.0% chlorhexidine gel (G8), 5% chitosan gel ± 0.2% chlorhexidine gel (G9), and 5% chitosan gel ± 2.0% chlorhexidine gel (G10). The antimicrobial action of the samples was tested against Candida albicans and Streptococcus mutans through antibiogram by measuring the inhibition halos. Data were statistically analyzed by Kruskal-Wallis and one-way ANOVA followed by Tukey test (p<0.05). The 2.0% chlorhexidine membrane (G5) and the disks containing 2.0% chlorhexidine gel (G8) showed the greatest inhibition halos for both microorganisms, with statistically significant difference when compared to others tested groups (p=0.008) only for Candida albicans inhibitions results. All the other formulations of membranes and gels showed inhibition halos, but without statistically significant difference. The bioadhesive chitosan-based oral membrane with 2% chlorhexidine and 2% chlorhexidine gel were the most effective in inhibiting the tested microorganisms.


Resumo O objetivo deste estudo foi avaliar in vitro o efeito antimicrobiano de uma bandagem oral bioadesiva de quitosana com clorexidina para o tratamento de infecções dos tecidos orais. Cinco bandagens de diferentes composições foram testadas: Quitosana 5% (G1); Quitosana 5% ± clorexidina a 0,2% (G2), Quitosana 5% ± clorexidina a 0,6% (G3), Quitosana 5% ± clorexidina a 1,0% (G4) e Quitosana 5% ± clorexidina a 2,0% (G5). Foram testados também 5 tipos de géis nas seguintes composições: Gel de Quitosana 5% (G6), Gel de clorexidina a 0,2% (G7), Gel de clorexidina a 2,0% (G8), Gel de Quitosana 5% ± clorexidina a 0,2% (G9) e Gel de Quitosana 5% ± clorexidina a 2,0% (G10). A ação antimicrobiana das amostras foi testada contra Candida albicans e Streptococcus mutans por meio do antibiograma, medindo o halo de inibição. Os dados foram analisados pelo teste de Kruskal-Wallis e ANOVA a um critério seguido pelo teste de Tukey (p<0,05). A membrana com 2,0% de clorexidina (G5) e os discos contendo gel com 2,0% de clorexidina (G8) apresentaram os maiores halos de inibição para os dois microrganismos, com diferença estatisticamente significativa em relação aos demais grupos testados (p=0,008) apenas nos resultados de inibição de C. albicans. Todas as outras formulações de membranas e géis apresentaram halo de inibição, mas sem diferença estatisticamente significativa. A bandagem oral bioadesiva de quitosana com gel de 2% de clorexidina foi a mais efetiva em inibir os microrganismos testados.


Subject(s)
Humans , Bacterial Adhesion/drug effects , Chlorhexidine/pharmacology , Gels , Anti-Infective Agents, Local/pharmacology , Mouth Mucosa/microbiology , Streptococcus mutans/drug effects , In Vitro Techniques , Candida albicans/drug effects , Microbial Sensitivity Tests , Chlorhexidine/administration & dosage , Anti-Infective Agents, Local/administration & dosage
13.
Braz. j. microbiol ; 49(1): 184-188, Jan.-Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-889206

ABSTRACT

ABSTRACT Removal of bacterial biofilm from the root canal system is essential for the management of endodontic disease. Here we evaluated the antibacterial effect of N-acetylcysteine (NAC), a potent antioxidant and mucolytic agent, against mature multispecies endodontic biofilms consisting of Actinomyces naeslundii, Lactobacillus salivarius, Streptococcus mutans and Enterococcus faecalis on sterile human dentin blocks. The biofilms were exposed to NAC (25, 50 and 100 mg/mL), saturated calcium hydroxide or 2% chlorhexidine solution for 7 days, then examined by scanning electron microscopy. The biofilm viability was measured by viable cell counts and ATP-bioluminescence assay. NAC showed greater efficacy in biofilm cell removal and killing than the other root canal medicaments. Furthermore, 100 mg/mL NAC disrupted the mature multispecies endodontic biofilms completely. These results demonstrate the potential use of NAC in root canal treatment.


Subject(s)
Humans , Acetylcysteine/pharmacology , Streptococcus mutans/drug effects , Actinomyces/drug effects , Enterococcus faecalis/drug effects , Biofilms/drug effects , Dental Pulp Diseases/microbiology , Lactobacillus salivarius/drug effects , Anti-Bacterial Agents/pharmacology , Streptococcus mutans/physiology , Actinomyces/physiology , Calcium Hydroxide/pharmacology , Chlorhexidine/pharmacology , Enterococcus faecalis/physiology , Dental Pulp Cavity/microbiology , Microbial Viability/drug effects , Lactobacillus salivarius/physiology
14.
J. appl. oral sci ; 26: e20170562, 2018. tab, graf
Article in English | LILACS, BBO | ID: biblio-954492

ABSTRACT

Abstract The objective of this study was to compare selective physical-mechanical properties, antibacterial effects and cytotoxicity of seven temporary restorative materials (TRM): five resin-based materials [Bioplic (B), Fill Magic Tempo (FM), Fermit inlay (F), Luxatemp LC (L) and Revotek LC (R)], and zinc oxide-eugenol cement (IRM) and glass ionomer cement (GIC) as the controls. Material and methods The physical-mechanical properties were evaluated by determining microleakage (ML), ultimate tensile strength (UTS) and Shore D hardness (SDH). In addition, the polymerization rate (Pr-1), depth of cure (DC), water sorption and solubility (WS/SL) were evaluated. The antimicrobial effects of the materials were assessed by biofilm accumulation of Streptococcus mutans (BT) and the direct contact test (DCT) by exposure to Enterococcus faecalis for 1 and 24 h, and cytotoxicity by MTT assay. The data were analyzed by ANOVA or Kruskall-Wallis tests, and a complementary post-hoc method (p<0.05). Results Group B, followed by FM and GIC had significantly lower percentages of microleakage in comparison with the other groups; Groups FM and L showed the highest WS, while Groups R and FM showed the significantly lowest SL values (p<0.05). Group R showed the statistically highest UTS mean and the lowest DC mean among all groups. Group F showed the lowest S. mutans biofilm accumulation (p=0.023). Only the Group L showed continued effect against E. faecalis after 1 h and 24 h in DCT. The L showed statistically lower viability cell when compared to the other groups. Conclusions These findings suggest the antibacterial effect of the temporary materials Fill Magic and Bioplic against S. mutans, while Luxatemp showed in vitro inhibition of S. mutans biofilm accumulation and E. faecalis growth. Regarding the cell viability test, Luxatemp was the most cytotoxic and Fill Magic was shown to be the least cytotoxic.


Subject(s)
Animals , Cattle , Mice , Streptococcus mutans/drug effects , Enterococcus faecalis/drug effects , Composite Resins/pharmacology , Composite Resins/chemistry , Fibroblasts/drug effects , Anti-Bacterial Agents/blood , Anti-Bacterial Agents/pharmacology , Polymethacrylic Acids/pharmacology , Polymethacrylic Acids/chemistry , Root Canal Filling Materials/pharmacology , Root Canal Filling Materials/chemistry , Solubility , Tensile Strength , Time Factors , Zinc Oxide-Eugenol Cement/pharmacology , Zinc Oxide-Eugenol Cement/chemistry , Materials Testing , Cell Survival/drug effects , Reproducibility of Results , Bisphenol A-Glycidyl Methacrylate/pharmacology , Bisphenol A-Glycidyl Methacrylate/chemistry , Dental Restoration, Temporary/methods , Glass Ionomer Cements/pharmacology , Glass Ionomer Cements/chemistry , Hardness Tests , Methylmethacrylates/pharmacology , Methylmethacrylates/chemistry
15.
J. appl. oral sci ; 26: e20170116, 2018. tab, graf
Article in English | LILACS, BBO | ID: biblio-893717

ABSTRACT

Abstract In a previous study, we demonstrated that the incorporation of doxycycline hyclate (DOX) into resin-modified glass ionomer cement (RMGIC) inhibited important cariogenic microorganisms, without modifying its biological and mechanical characteristics. In this study, we keep focused on the effect of that experimental material as a potential therapy for arresting residual caries by analyzing other in vitro properties and conducting a pilot clinical trial assessing the in vivo effect of DOX-containing RMGIC on residual mutans streptococci after partial carious removal in primary molars. Specimens of the groups RMGIC (control); RMGIC + 1.5% DOX; RMGIC + 3% DOX; and RMGIC + 4.5% DOX were made to evaluate the effect of DOX incorporation on surface microhardness and fluoride release of RMGIC and against biofilm of Streptococcus mutans. Clinical intervention consisted of partial caries removal comparing RMGIC and RMGIC + 4.5% DOX as lining materials. After 3 months, clinical and microbiologic evaluations were performed. Data were submitted to ANOVA/Tukey or Wilcoxon/Mann-Whitney set as α=0.05. Fluoride release and surface microhardness was not influenced by the incorporation of DOX (p>0.05). There was a significant reduction of S. mutans biofilm over the material surface with the increase of DOX concentration. After clinical trial, the remaining dentin was hard and dry. Additionally, mutans streptococci were completely eliminated after 3 months of treatment with RMGIC + 4.5% DOX. The incorporation of DOX provided better antibiofilm effect, without jeopardizing fluoride release and surface microhardness of RMGIC. This combination also improved the in vivo shortterm microbiological effect of RMGIC after partial caries removal.


Subject(s)
Humans , Male , Female , Child, Preschool , Child , Doxycycline/chemistry , Dental Caries/drug therapy , Glass Ionomer Cements/chemistry , Anti-Bacterial Agents/chemistry , Streptococcus mutans/isolation & purification , Streptococcus mutans/drug effects , Time Factors , Materials Testing , Colony Count, Microbial , Reproducibility of Results , Treatment Outcome , Doxycycline/pharmacology , Dentin/drug effects , Dentin/microbiology , Fluorides/chemistry , Glass Ionomer Cements/pharmacology , Hardness Tests , Anti-Bacterial Agents/pharmacology
16.
J. appl. oral sci ; 26: e20170270, 2018. tab, graf
Article in English | LILACS, BBO | ID: biblio-893712

ABSTRACT

Abstract Although resin composites are widely used in the clinical practice, the development of recurrent caries at composite-tooth interface still remains as one of the principal shortcomings to be overcome in this field. Objectives To evaluate the activity against S. mutans biofilm of model resin composites incorporating different concentrations of ZnO-nanoparticles (ZnO-NP) and characterize their physicochemical properties. Materials and Methods Different concentrations of ZnO-NP (wt.%): E1=0, E2=0.5, E3=1, E4=2, E5=5 and E6=10 were incorporated into a model resin composite consisting of Bis-GMA-TEGDMA and barium borosilicate particles. The activity against S. mutans biofilm was evaluated by metabolic activity and lactic acid production. The following physicochemical properties were characterized: degree of conversion (DC%), flexural strength (FS), elastic modulus (EM), hardness (KHN), water sorption (Wsp), water solubility (Wsl) and translucency (TP). Results E3, E4, E5 and E6 decreased the biofilm metabolic activity and E5 and E6 decreased the lactic acid production (p<0.05). E6 presented the lowest DC% (p<0.05). No significant difference in FS and EM was found for all resin composites (p>0.05). E5 and E6 presented the lowest values of KHN (p<0.05). E6 presented a higher Wsp than E1 (p<0.05) and the highest Wsl (p<0.05). The translucency significantly decreased as the ZnO- NP concentration increased (p<0.05). Conclusions The incorporation of 2 - 5 wt.% of ZnO-NP could endow antibacterial activity to resin composites, without jeopardizing their physicochemical properties.


Subject(s)
Streptococcus mutans/drug effects , Zinc Oxide/pharmacology , Zinc Oxide/chemistry , Composite Resins/pharmacology , Composite Resins/chemistry , Nanoparticles/chemistry , Polyethylene Glycols/pharmacology , Polyethylene Glycols/chemistry , Polymethacrylic Acids/pharmacology , Polymethacrylic Acids/chemistry , Reference Values , Solubility , Streptococcus mutans/growth & development , Surface Properties , Materials Testing , Water/chemistry , Microscopy, Electron, Scanning , Linear Models , Reproducibility of Results , Analysis of Variance , Bisphenol A-Glycidyl Methacrylate/pharmacology , Bisphenol A-Glycidyl Methacrylate/chemistry , Silicates/pharmacology , Silicates/chemistry , Barium Compounds/pharmacology , Barium Compounds/chemistry , Pliability , Biofilms/growth & development , Biofilms/drug effects , Elastic Modulus , Hardness Tests
17.
J. appl. oral sci ; 26: e20170065, 2018. graf
Article in English | LILACS, BBO | ID: biblio-893689

ABSTRACT

Abstract Considering oral diseases, antibiofilm compounds can decrease the accumulation of pathogenic species such as Streptococcus mutans at micro-areas of teeth, dental restorations or implant-supported prostheses. Objective To assess the effect of thirteen different novel lactam-based compounds on the inhibition of S. mutans biofilm formation. Material and methods We synthesized compounds based on γ-lactones analogues from rubrolides by a mucochloric acid process and converted them into their corresponding γ-hydroxy-γ-lactams by a reaction with isobutylamine and propylamine. Compounds concentrations ranging from 0.17 up to 87.5 μg mL-1 were tested against S. mutans. We diluted the exponential cultures in TSB and incubated them (37°C) in the presence of different γ-lactones or γ-lactams dilutions. Afterwards, we measured the planktonic growth by optical density at 630 nm and therefore assessed the biofilm density by the crystal violet staining method. Results Twelve compounds were active against biofilm formation, showing no effect on bacterial viability. Only one compound was inactive against both planktonic and biofilm growth. The highest biofilm inhibition (inhibition rate above 60%) was obtained for two compounds while three other compounds revealed an inhibition rate above 40%. Conclusions Twelve of the thirteen compounds revealed effective inhibition of S. mutans biofilm formation, with eight of them showing a specific antibiofilm effect.


Subject(s)
Streptococcus mutans/drug effects , Biofilms/drug effects , beta-Lactams/pharmacology , Lactones/pharmacology , Anti-Bacterial Agents/pharmacology , Plankton/growth & development , Plankton/drug effects , Streptococcus mutans/growth & development , Microscopy, Electron, Scanning , Colony Count, Microbial , Microbial Sensitivity Tests , Reproducibility of Results , Analysis of Variance , Biofilms/growth & development , beta-Lactam Resistance/drug effects , beta-Lactams/chemical synthesis , Dose-Response Relationship, Drug , Microbial Viability/drug effects , Gentian Violet , Lactones/chemical synthesis , Anti-Bacterial Agents/chemical synthesis
18.
Bauru; s.n; 2018. 132 p. tab, graf, ilus.
Thesis in English | LILACS, BBO | ID: biblio-906807

ABSTRACT

The objective of this study was to evaluate the antimicrobial and anti-caries effects of two plant extracts. The first chapter dealt with a review of the literature whose objective was to discuss the antimicrobial potential of Brazilian natural agents on the biofilm related to dental caries and gingivitis/periodontal disease. The research of the articles was carried out using PubMed. We found a total of 23 papers. Most of the studies were performed using planktonic microorganisms or under clinical trials. Nineteen articles were focused on cariogenic bacteria. From these nineteen articles, eleven were also about periodontopathogenic bacteria. Four studies addressed only periodontopathogenic bacteria. The most tested Brazilian natural agents were green propolis, essential oils of Lippia sidoides and Copaifera sp. Most of the tested agents showed similar results when compared to positive control (essential oils and extracts) or better effect than negative control (green propolis). More studies involving protocols closer to the clinical condition and the use of response variables that allows understanding the mechanism of action of natural agents are necessary before the incorporation of these natural agents into dental products. The second chapter aimed to test the effect of the hydroalcoholic extracts of Myracrodruon urundeuva All. and Qualea grandiflora Mart. leaves on the viability of the microcosm biofilm and on the prevention of enamel demineralization. The microcosm biofilm was produced on bovine enamel, using human saliva pool mixed with McBain saliva (0.2% sucrose) for 14 days. The biofilm was treated daily with the extracts for 1 min. M. urundeuva at 100, 10 and 0.1 µg/ml and Q. grandiflora at 100 and 0.1 µg/ml reduced cell viability similarly to the positive control and significantly more than negative control. M. urundeuva at 1000, 100 and 0.1 µg/ml were able to reduce the counting formation unit-CFU counting of lactobacilli sp. and Streptococcus mutans, while Q. grandiflora at 1000 and 1.0 µg/ml significantly reduced the S. mutans CFU counting. On the other hand, the natural extracts did not reduce the production of extracellular polyssacharides, lactic acid and the development of enamel caries lesions. The third chapter aimed to evaluate the effect of hydroalcoholic extracts of M. urundeuva and Q. grandiflora (alone or combined) on the viability of S. mutans biofilm and the prevention of enamel demineralization. S. mutans strain (ATCC 21175) was reactivated in BHI broth. Minimum inhibitory concentration, minimum bactericidal concentration, minimum biofilm inhibitory concentration and minimum biofilm eradication concentration were determined to choose the concentrations to be tested under the biofilm model. S. mutans biofilm (5x105 CFU/ml) was produced on bovine enamel using McBain saliva with 0.2% sucrose for 3 days. The biofilm was treated daily with the extracts for 1 min. M. urundeuva (isolated or combined) at concentrations equal or higher than 0.625 mg/ml was able to reduce the bacteria viability, whereas Q. grandiflora extract alone showed antimicrobial effect at 5 mg/ml only (p<0.05). On the other hand, none of the extracts was able to reduce the development of enamel caries lesions. Despite the tested natural extracts have antimicrobial effect; they are unable to prevent caries in enamel.(AU)


O objetivo foi avaliar os efeitos antimicrobiano e anti-cárie de dois extratos de plantas. O primeiro capítulo se referiu a uma revisão da literatura cujo objetivo foi discutir o potencial antimicrobiano dos agentes naturais brasileiros sobre o biofilme relacionado à cárie dentária e à gengivite/doença periodontal. A pesquisa dos artigos foi realizada usando o PubMed. Foram encontrados 23 trabalhos. A maioria dos estudos foi realizada utilizando microorganismos na fase planctônica ou ensaios clínicos. Dezenove artigos foram focados em bactérias cariogênicas. Dos dezenove artigos, onze também eram sobre bactérias periodontopatogênicas. Quatro estudos abordaram apenas bactérias periodontopatogênicas. Os agentes naturais brasileiros mais testados foram própolis verde, óleos essenciais de Lippia sidoides e Copaifera sp. Os agentes testados apresentaram resultados similares quando comparados ao controle positivo (óleos essenciais e extratos) ou melhor efeito que o controle negativo (própolis verde). Mais estudos próximos da condição clínica e o uso de variáveis de resposta que permitam entender o mecanismo de ação são necessários, para permitir a incorporação desses agentes naturais em produtos odontológicos. O segundo capítulo teve como objetivo testar o efeito dos extratos hidroalcoólicos de Myracrodruon urundeuva All. e Qualea grandiflora Mart. sobre a viabilidade do biofilme microcosmo e na prevenção da desmineralização do esmalte. O biofilme microcosmo foi produzido em esmalte bovino, utilizando pool de saliva humana misturada à saliva de McBain (0,2% de sacarose) durante 14 dias. O biofilme foi tratado diariamente com os extratos durante 1 min. M. urundeuva a 100, 10 e 0,1 µg/ml e Q. grandiflora a 100 e 0,1 µg/ml reduziram a viabilidade dos microrganismos de forma semelhante ao controle positivo e significativamente maior do que o controle negativo. M. urundeuva a 1000, 100 e 0,1 µg/ml foi capaz de reduzir a contagem de Unidade formadora de colônia-UFC para Lactobacilos totais e Streptococcus mutans, enquanto a Q. grandiflora a 1000 e 1,0 µg/ml reduziu significativamente a contagem de UFC para S. mutans. Os extratos naturais não conseguiram reduzir a produção de polissacarídeos extracelulares-PEC, ácido lático e o desenvolvimento da lesão cariosa em esmalte. O terceiro capítulo teve como objetivo avaliar o efeito dos extratos hidroalcoólicos de M. urundeuva. e Q. grandiflora (sozinhos ou combinados) sobre a viabilidade do biofilme de S. mutans e na prevenção da desmineralização do esmalte. Cepa de S. mutans (ATCC 21175) foi reativada em caldo BHI. Concentração inibitória mínima, concentração bactericida mínima, concentração inibitória mínima de biofilme e concentração de erradicação mínima de biofilme foram determinadas para escolher as concentrações a serem testadas sob o modelo de biofilme. O biofilme de S. mutans (5x105 CFU/ml) foi produzido em esmalte bovino, utilizando saliva de McBain com 0,2% de sacarose durante 3 dias. O biofilme foi tratado diariamente com os extratos durante 1 min. M. urundeuva (isolada ou combinada) nas concentrações iguais ou superiores a 0,625 mg/ml foi capaz de reduzir a viabilidade das bactérias, enquanto que o extrato da Q. grandflora apresentou efeito antimicrobiano somente a 5 mg/ml (p<0,05). Nenhum dos extratos reduziu o desenvolvimento da lesão da cárie. Apesar dos extratos naturais terem efeito antimicrobiano, são incapazes de prevenir o desenvolvimento da lesão cariosa em esmalte.(AU)


Subject(s)
Humans , Animals , Cattle , Anacardiaceae/chemistry , Anti-Infective Agents/pharmacology , Biofilms/drug effects , Dental Enamel/microbiology , Magnoliopsida/chemistry , Plant Extracts/pharmacology , Tooth Demineralization/prevention & control , Microbial Sensitivity Tests , Microradiography , Reproducibility of Results , Saliva/microbiology , Streptococcus mutans/drug effects , Streptococcus mutans/growth & development , Time Factors
19.
Rio de Janeiro; s.n; s.n; 2018. 62 p. tab, ilus, graf.
Thesis in Portuguese | LILACS, BBO | ID: biblio-964018

ABSTRACT

O objetivo principal do presente estudo, considerando a importância do controle do biofilme, foi avaliar in situ a ação antimicrobiana e análise elementar da incorporação de diacetato de clorexidina(CHX) em resinas acrílicas a base de PMMA. Além disso, avaliar ex vivo o mecanismo de lixiviação da clorexidina por até 14 dias. Primeiramente, foram recrutados 32 indivíduos para utilização de dispositivos acrílicos intraorais palatinos por 24 horas contendo 6 corpos de prova(CPs), sendo subdivididos em 2 grupos: com clorexidina (1%) e sem CHX. A avaliação da atividade antimicrobiana foi realizada por meio de contagem de colônias de microorganismos totais e Estreptococos do grupo mutans. Então, os grupos foram avaliados estatisticamente pelo teste de wilcoxon. A análise estatística aplicada foi o teste de Wilcoxon. No segundo teste, foi feita a análise elementar dos CPs(n=10) por meio das médias das intensidade dos elementos, antes e após o uso do dispositivo, por meio da fluorescência de raio X. Ao final, foi avaliado ex vivo a liberação de clorexidina cumulativa, em meio fechado contendo saliva dos indivíduos(n=5) por até 14 dias, através da ressonância magnética nuclear (RMN). As análises estatísticas da RMN, foram avaliadas pelo programa AMIX e metaboloanalyst. Os resultados mostraram, que para atividade antimicrobiana não houve diferença estatística (p>0,05) entre os grupos. Foi detectado a presença da molécula de clorexidina, antes e após a inserção dos CPs com CHX na cavidade bucal. Já para liberação de clorexidina, foi detectada a droga ao longo de 14 dias em meio fechado para a grupo teste, com liberação maior nas primeiras 24 horas. Conclui-se que, foi comprovada a presença do fármaco na resina acrílica após 24 horas em meio bucal, e seu mecanismo de lixiviação no meio fechado por até 14 dias. Porém, não foram encontrados resultados que confirmem a presença de um potencial antimicrobiano do fármaco, nas concentrações utilizadas nos corpos de prova in situ em 24 horas.


The main objective of the present study, considering the importance of biofilm control, was to evaluate in situ the antimicrobial action and elemental composition of the incorporation of chlorhexidine diacetate (CHX) in acrylic resins based on PMMA. In addition, ex vivo evaluation of the chlorhexidine release mechanism to 14 days. Firstly, 32 individuals were recruited for 24-hour palatal intraoral acrylic devices containing 6 test specimens (SPs), divided into 2 groups: with chlorhexidine (1%) and without CHX. The evaluation of the antimicrobial activity was performed by colonies count of total microorganisms and streptococci mutans group. Then, the groups were statistically evaluated by the wilcoxon test. The statistical analysis applied was the Wilcoxon test. In the second test, elemental analysis of the SPs (n = 10) was done by means of the means intensity of the elements, before and after the use of the device, by X-ray fluorescence. At the end, the release was evaluated ex vivo of cumulative chlorhexidine in a becker containing saliva of the individuals (n = 5) for 14 days, through nuclear magnetic resonance (NMR). The NMR analyzes were evaluated by AMIX and metaboloanalyst. The results showed that for antimicrobial activity there was no statistical difference (p> 0.05) between the groups. The presence of the chlorhexidine molecule was detected before and after the insertion of SPs with CHX in the oral cavity. As for chlorhexidine release, the drug was detected over 14 days in a closed medium for the test group, with a greater release in the first 24 hours. It was concluded that the presence of the drug in the acrylic resin after 24 hours in oral cavity was verified, and its release mechanism in the closed local for 14 days. However, no results were found to confirm the presence of an antimicrobial potential of the drug at the concentrations used in the in situ test specimens in 24 hours


Subject(s)
Humans , Male , Female , Adolescent , Adult , Acrylic Resins , Chlorhexidine/pharmacology , Polymethyl Methacrylate , Dental Plaque/prevention & control , Anti-Infective Agents, Local/pharmacology , Streptococcus mutans/drug effects , Magnetic Resonance Spectroscopy , Statistics, Nonparametric , Fluorescence
20.
J. appl. oral sci ; 25(5): 541-550, Sept.-Oct. 2017. tab, graf
Article in English | LILACS, BBO | ID: biblio-893660

ABSTRACT

Abstract Objectives: Addition of chlorhexidine has enhanced the antimicrobial effect of glass ionomer cement (GIC) indicated to Atraumatic Restorative Treatment (ART); however, the impact of this mixture on the properties of these materials and on the longevity of restorations must be investigated. The aim of this study was to evaluate the effects of incorporating chlorhexidine (CHX) in the in vitro biological and chemical-mechanical properties of GIC and in vivo clinical/ microbiological follow-up of the ART with GIC containing or not CHX. Material and Methods: For in vitro studies, groups were divided into GIC, GIC with 1.25% CHX, and GIC with 2.5% CHX. Antimicrobial activity of GIC was analyzed using agar diffusion and anti-biofilm assays. Cytotoxic effects, compressive tensile strength, microhardness and fluoride (F) release were also evaluated. A randomized controlled trial was conducted on 36 children that received ART either with GIC or GIC with CHX. Saliva and biofilm were collected for mutans streptococci (MS) counts and the survival rate of restorations was checked after 7 days, 3 months and one year after ART. ANOVA/Tukey or Kruskal-Wallis/ Mann-Whitney tests were performed for in vitro tests and in vivo microbiological analysis. The Kaplan-Meier method and Log rank tests were applied to estimate survival percentages of restorations (p<0.05). Results: Incorporation of 1.25% and 2.5% CHX improved the antimicrobial/anti-biofilm activity of GIC, without affecting F release and mechanical characteristics, but 2.5% CHX was cytotoxic. Survival rate of restorations using GIC with 1.25% CHX was similar to GIC. A significant reduction of MS levels was observed for KM+CHX group in children saliva and biofilm 7 days after treatment. Conclusions: The incorporation of 1.25% CHX increased the in vitro antimicrobial activity, without changing chemical-mechanical properties of GIC and odontoblast-like cell viability. This combination improved the in vivo short-term microbiological effect without affecting clinical performance of ART restorations.


Subject(s)
Humans , Male , Female , Child, Preschool , Child , Chlorhexidine/pharmacology , Chlorhexidine/chemistry , Dental Atraumatic Restorative Treatment/methods , Glass Ionomer Cements/pharmacology , Glass Ionomer Cements/chemistry , Anti-Infective Agents, Local/pharmacology , Reference Values , Saliva/microbiology , Streptococcus mutans/growth & development , Streptococcus mutans/drug effects , Tensile Strength , Time Factors , In Vitro Techniques , Materials Testing , Candida albicans/growth & development , Candida albicans/drug effects , Colony Count, Microbial , Reproducibility of Results , Analysis of Variance , Treatment Outcome , Statistics, Nonparametric , Biofilms/growth & development , Biofilms/drug effects , Compressive Strength , Fluorides/chemistry , Hardness Tests , Lactobacillus acidophilus/growth & development , Lactobacillus acidophilus/drug effects , Odontoblasts/drug effects
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