In-vitro evaluation of the effectiveness of polyphenols based strawberry extracts for dental bleaching.

To formulate a dental bleaching agent with strawberry extract that has potent bleaching properties and antimicrobial efficacy. Enamel specimens (3 × 3 × 2 mm3) were prepared. Quaternary Ammonium Silane (CaC2 enriched) was homogenized with fresh strawberries: Group 1: supernatant strawberry (10 g) extract < Group 2: supernatant strawberry (10 g) extract + 15%HA (Hydroxyapatite) < Group 3: supernatant strawberry (10 g) extract + 15% (HA-2%k21) < Group 4: supernatant strawberry (20 g) extract only (20 g strawberries) < Group 5: supernatant strawberry (20 g) extract + 15% HA < Group 6: supernatant strawberry (20 g) extract + 15% (HA-2%K21) < Group 7: In-office Opalescence Boost 35%. Single-colony lactobacillus was examined using confocal microscopy identifying bacterial growth and inhibition in presence of bleaching agents using 300 µL aliquot of each bacterial culture. Images were analysed by illuminating with a 488 nm argon/helium laser beam. Colour difference (∆E00) was calculated using an Excel spreadsheet implementation of the CIEDE2000 colour difference formula and colour change measured between after staining and after bleaching. Scanning electron microscope was used to image specimens. Raman spectra were collected, and enamel slices were used for STEM/TEM analysis. HPLC was used for strawberry extract analysis. Nano-indentation was performed and X-ray photoelectron spectroscopy. Antioxidant activity was determined along with molecular simulation. hDPSCs were expanded for Alamar Blue Analysis and SEM. Mean colour change was significantly reduced in group 1 compared to other groups (p < 0.05). CLSM showed detrimental effects of different strawberry extracts on bioflms, especially with antimicrobial (p < 0.05). Groups 1, 2 and 3 showed flatter/irregular surfaces with condensation of anti-microbial in group 3. In strawberry specimens, bands predominate at 960 cm-1. HPLC determined the strawberry extracts content. Molecular simulation verified interaction between calcium and polyphenol components. XPS peak-fitted high-resolution corresponding results of Ca2p3/2 and Ca2p1/2 for all k21 groups. Combination of 10 g strawberry extract supernatant and 15% (hydroxyapatite 2%k21) improved the whiteness and provided additional antimicrobial potential. The novel strawberry extract and antimicrobial based dental formulation had immediate bleaching effect without promoting significant changes in enamel morphology.

Spectrophotometric evaluation of coronal discoloration induced by bioceramic root canal filling materials / Evaluación espectrofotométrica de la decoloración coronal inducida por materiales biocerámicos de obturación del conducto radicular

The aim of this study is to evaluate the crown discoloration induced by bioceramic root canal filling materials (OrthoMTA and iRoot SP) compared to AH Plus. Material and Methods: Sixty intact mandibular single rooted premolars were sectioned 2 mm below the cemento-enamel junction, prepared, and randomly assigned into four groups according to the root filling materials: OrthoMTA, iRoot SP, AH Plus and unfilled. Results: Before placement of the materials in the pulp chamber and the coronal third of the root, the spectral reflectance lines of the crowns were recorded by a digital spectrophotometer at baseline, and after filling at 1 week and 1, 3 and 6 months and ∆Ε values were calculated. All materials used induced clinically perceptible crown discoloration (∆Ε>3.7) and no significant difference was detected between these materials (p>0.05). Regardless of the material, discoloration progressed significantly within the three months (p<0.05) however, at 6 months, the discoloration reduced for AH Plus and no further increase for bioceramic materials was detected. Conclusion: Bioceramic root filling materials tested induced clinically perceptible crown discoloration and their application in the esthetic zone should be performed with caution.

Objetivo: El objetivo de este estudio es evaluar la decoloración de la corona inducida por materiales biocerámicos de obturación del conducto radicular (OrthoMTA e iRoot SP) en comparación con AH Plus. Material y Métodos: Se seccionaron sesenta premolares mandibulares de raíz única intactos, 2 mm por debajo de la unión cemento-esmalte, se prepararon y se asignaron al azar en cuatro grupos de acuerdo con los materiales de obturación radicular: OrthoMTA, iRoot SP, AH Plus y sin relleno. Resultados:Antes de la colocación de los materiales en la cámara pulpar y el tercio coronal de la raíz, las líneas de reflectancia espectral de las coronas se registraron con un espectrofotómetro digital al inicio del estudio, y a la semana 1, así como a 1, 3 y 6 meses, y los valores ?? fueron calculados. Todos los materiales utilizados indujeron una decoloración de la corona clínicamente perceptible (??> 3,7) y no se detectaron diferencias significativas entre estos materiales (p> 0,05). Independientemente del material, la decoloración progresó significativamente dentro de los tres meses (p<0.05); sin embargo, a los 6 meses, la decoloración se redujo para AH Plus y no se detectó ningún aumento adicional para los materiales biocerámicos. Conclusiones: Los materiales biocerámicos de obturación radicular probados indujeron una decoloración de la corona clínicamente perceptible y su aplicación en la zona estética debe realizarse con precaución.