Glycerol Salicylate-based Pulp-Capping Material Containing Portland Cement

The purpose of this study was to evaluate the water sorption, solubility, pH and ability to diffuse into dentin of a glycerol salicylate-based, pulp-capping cement in comparison to a conventional calcium hydroxide-based pulp capping material (Hydcal). An experimental cement was developed containing 60% glycerol salicylate resin, 10% methyl salicylate, 25% calcium hydroxide and 5% Portland cement. Water sorption and solubility were determined based on mass changes in the samples before and after the immersion in distilled water for 7 days. Material discs were stored in distilled water for 24 h, 7 days and 28 days, and a digital pHmeter was used to measure the pH of water. The cement's ability to diffuse into bovine dentin was assessed by Raman spectroscopy. The glycerol salicylate-based cement presented higher water sorption and lower solubility than Hydcal. The pH of water used to store the samples increased for both cements, reaching 12.59±0.06 and 12.54±0.05 after 7 days, for Hydcal and glycerol salicylate-based cements, respectively. Both cements were able to turn alkaline the medium at 24 h and sustain its alkalinity after 28 days. Hydcal exhibited an intense diffusion into dentin up to 40 µm deep, and the glycerol salicylate-based cement penetrated 20 µm. The experimental glycerol salicylate-based cement presents good sorption, solubility, ability to alkalize the surrounding tissues and diffusion into dentin to be used as pulp capping material.

O objetivo deste estudo foi avaliar a sorção e solubilidade em água, pH e habilidade de difusão na dentina de um cimento para capeamento pulpar à base de glicerol salicilato e compará-lo a um cimento comercial para capeamento pulpar à base de hidróxido de cálcio (Hydcal). Um cimento experimental contendo 60% de resina de glicerol salicilato, 10% de salicilato de metila, 25% de hidróxido de cálcio e 5% de cimento Portland foi formulado. Sorção e solubilidade em água foram determinadas a partir da alteração na massa de espécimes antes e após a imersão em água destilada por 7 dias. Discos dos cimentos foram armazenados em água destilada por 24h, 7 dias e 28 dias e o pH da água foi aferido após cada período. A habilidade de difundir-se no interior de dentina bovina foi avaliada por espectroscopia Raman. O cimento à base de glicerol salicilato apresentou maior sorção e menor solubilidade em comparação com o Hydcal. O pH da água de armazenamento dos espécimes aumentou para ambos os cimentos, chegando a 12,59±0,06 e 12,54±0,05 após 7 dias, para o Hydcal e o cimento à base de glicerol salicilato, respectivamente. Os cimentos foram capazes de promover a alcalinização do meio após 24h e sustentaram a alcalinidade após 28 dias. Hydcal exibiu intensa difusão na dentina até 40 μm de profundidade e o cimento à base de glicerol salicilato penetrou 20 μm. O cimento experimental à base de glicerol salicilato apresentou adequada sorção, solubilidade, habilidade de alcalinizar o meio e difundir-se no interior da dentina para uso como um material para capeamento pulpar.

Influence of radiopaque fillers on physicochemical properties of a model epoxy resin-based root canal sealer

Objective: To verify the influence of radiopaque fillers on an epoxy resin-based sealer. Material and Methods: Experimental sealers were formulated by adding 20%, 40%, 60%, 80%, 100% and 120% of calcium tungstate, ytterbium trifluoride or barium sulphate by weight to an epoxy-resin-base. Setting time, flow, film thickness, radiopacity, sorption, solubility, pH and push-out bond strength were evaluated. Results: The setting time ranged from 373 to 612.66 min, the flow varied from 13.81±0.49 to 22.49±0.37 mm, and the film thickness ranged from 16.67±5.77 to 33.33±11.54 µm. The lowest pH was 5.47±0.53, and the highest was 6.99±0.03. Radiopacity varied from 0.38±0.04 to 2.57±0.21 mmAl and increased with the amount of filler. Calcium tungstate sealers had a higher sorption and solubility than other sealers. There was no significant difference in the push-out bond strength among the fillers at the 120% concentration. CONCLUSION: The inorganic fillers evaluated and their concentrations affect the physicochemical properties of an epoxy resin-based root canal sealer. .