Dentine desensitization induced by prophylactic and air-polishing procedures: An in vitro dentine permeability and confocal microscopy study

<bold>Objectives: </bold>The exposure of dentinal tubules causes fluid movement and dentinal hypersensitivity. This study aimed at evaluating the dentine permeability after prophylactic measures performed on exposed dentine after immersion in artificial saliva and citric acid challenge. Confocal microscopy was performed to evaluate the percentage of occluded tubules (OCT%) and the changes in dentine morphology.<bold>Methods: </bold>Prophy-powders and pastes were tested in this study. An oxalic acid liner was used as a positive control. Dentine discs from human third molars were treated with each material and the dentine permeability was evaluated using a fluid filtration system working at 20cm H(2)O. Artificial saliva and citric acid were used for the determination of changes in dentine permeability. The percentage of tubule occlusion capability (OCT%) was evaluated using confocal microscopy.<bold>Results: </bold>All the products used in this study were able to significantly reduce the dentine permeability of acid-etched specimens. The use of the bioactive glass and sodium bicarbonate showed the highest values in dentine permeability reduction. However, the air-polishing procedures performed with Sylc bioactive glass powder created a dentine surface resistant to citric acid attack.<bold>Conclusion: </bold>Bioactive glass is suitable for treatment of dentinal hypersensitivity by creating a dentine surface resistant to citric acid attack. [ABSTRACT FROM AUTHOR]