ABSTRACT
Curcumin-mediated Photodynamic Inactivation (PDI) has shown great potential to disinfect specific sites on tooth enamel but may involve contact with restorative materials. Thus, before use in dentistry, it is necessary to investigate whether the PDI protocol causes undesirable changes in the surfaces of aesthetic restorative materials and dental enamel. This study investigated the effect of PDI mediated by curcumin (CUR) in a liquid crystal precursor system on color stability (ΔE), surface roughness (Ra), and microhardness (kgf) of three different composite resins and bovine dental enamel specimens. The microhardness and roughness readings were performed 60 days after the treatments while the color readings were performed immediately, 24, 48, and 72 h, 7, 14, 21, 30, and 60 days after the treatments. Results showed that CUR mediated-PDI does not seem to have the potential to promote any esthetic or mechanical changes to the surface of tooth enamel and can be applied safely in clinical practice. However, the results on color, roughness, and hardness obtained for composite resins show that some negative effects can be produced, depending on the type of restorative material; more experiments must be performed with different formulations and, perhaps, with lower concentrations of CUR.
ABSTRACT
Introduction: Composite resins are materials that can present color changing when exposed to pigments. Objective: The aim of this study was to evaluate, in vitro, the color changing of composites after immersion in different substances for different periods. Material and methods: Two microhybrid composite resins: Charisma (Heraeus - Kulzer) and Opallis (FGM) were used. Red wine and acai pulp were also used as immersion medium. For this study, 32 specimens with 10 mm of diameter and 2 mm of thickness were used, divided into 4 groups: Group 1 - Opallis composite immersed in red wine solution; Group 2 - Opallis composite immersed in acai berry pulp solution; Group 3 - Charisma composite immersed in red wine solution; Group 4 - Charisma composite immersed in acai berry pulp solution. The specimens were evaluated in the following time periods: T0 - baseline, T1 - 24 hours, T2 - 48 hours, T3 - 72 hours and T4 - 96 hours. For the assessment of staining, a spectrophotometer for colorimetry was used (Color Guide 45 / 0, PCB 6807 BYK-Gardner Gerestsried GmBH, Germany), and the values obtained were transferred to a computer and recorded according to CIELAB system. Results: The data were evaluated using Kruskal- Wallis non-parametric tests with the following mean values for the immersion periods of 24, 48, 72 and 96 hours, respectively: G1 - 7.35, 7.84, 9.04,10.48; G2 - 2.92, 4.15, 4.30, 4.64; G3 - 3.14, 7.35, 8.13, 8.43, G4 - 4.49, 5.99, 6.92, 6.76. Conclusion: Red wine showed a higher tendency toward altering the composite color than acai berry pulp. In addition, no significant difference was found concerning to the behavior of the two composite resins. Concerning to the immersion time periods, significant differences were only observed among the groups in the 24 hour time period.
ABSTRACT
O presente estudo avaliou a suscetibilidade geral de patógenos da flora salivar à terapia fotodinâmica (TFD) após a sensibilização com curcumina e exposição ao LED (Light Emitting Diode) de 450 nm (± 10) para evitar contaminação direta e cruzada nos consultórios odontológicos. Para isso, uma amostra de 10 ml de saliva não estimulada foi coletada a partir de um voluntário para a contagem de bactérias após a fase experimental, e os resultados foram analisados. Quatorze diferentes grupos foram avaliados: G1) L-FS (1,5g/l) + por 1min; G2) L-FS (1,5g/l) + por 5 min; G3) L-FS (3,0g/l) + por 1 min; G4) L-FS (3,0g/l) + por 5min; G5) L+ FS-por 1 min; G6) L+ FS-por 5 min; G7) L+ FS (1,5g/l) + por 1 min; G8) L+ FS (1,5g/l) + por 5 min; G9) L+ FS (3,0g/l)+por 1 min ; G10 ) L+ FS(3,0g/l)+ por 5 min; G11) Clorexidina 0,12% por 1 min; G12) Clorexidina 0,12% por 5 min; G13) Salina por 1 min; G14) Salina por 5 min. Salina foi o grupo controle negativo e clorexidina, o controle positivo. Após cada teste efetuadoforam realizadas diluições seriadas e as amostras resultantes foram semeadas em placas de ágar sangue para depois serem levadas a estufa em condições de microaerofilia onde houve o crescimento microbiológico. Um pesquisador treinado e calibrado determinouo número de unidades formadoras de colônia (UFC) por cálculo matemático. A análise estatística (ANOVA e TUKEY HSD) foi realizada para analisar se houve ou não diferença estatística significante entre os grupos, e de acordo com os resultados, a TFD para redução quantitativa dos patógenos encontrados na cavidade oral é eficaz, no entanto a clorexidina continua sendo considerada o padrão ouro quando se trata de descontaminação oral geral e consequente diminuição do risco de transmissão de doenças infecto- contagiosas seja de forma direta ou indireta
The present study assessed the general susceptibility of pathogens salivary flora to the photodynamic therapy (PDT) after sensitization with curcumin and exposure to the LED (Light Emitting Diode) of 450 nm (± 10) to avoid direct and cross contamination in dental offices. For this, a sample of 10 ml of unstimulated saliva was collected from a volunteer for the bacterial count after the experimental phase and the results were recorded. Fourteen different groups were evaluated: G1) L-PS (1,5g/l) + for 1min ; G2 ) L-PS (1,5g/l)+ for 5 min ; G3) L-PS( 3,0g/l)+ for 1 min ; G4) L-PS( 3,0g/l)+ for 5min ; G5) L+ PS-for 1 min ; G6) L+ PS-for 5 min ; G7)L+ PS (1,5g/l)+ for 1 min ; G8) L+ PS (1,5g/l)+ for 5 min; G9) L+ PS (3,0g/l)+ for 1 min ; G10 ) L+ PS(3,0g/l)+ for 5 min; G11) Chlorhexidine 0,12% for 1 min; G12) Chlorhexidine 0,12% for 5 min; G13) Saline for 1 min; G14) Saline for 5 min. Saline was thenegative control group and chlorhexidine, the positive control. After each test, serial dilutions were performed and the resulting samples were plated on blood agar plates. Thereafter, the plates were placed in the stove under microaerophilic conditionsfor microbial growth. A trained and calibrated researcher determined the number of colony forming units (CFU) by mathematical calculation. Statistical analysis (ANOVA and TUKEY HSD) was realized to examine if there was or there was not a statistically significant difference between groups, and according to the results, PDT to quantitative reduction of pathogens found in the oral cavity is effective, however, chlorhexidine still considered the gold standard to oral decontamination and subsequent reduction of the overall risk of transmission of infectious diseases either directly or indirectly
