On surface mediated interactions related to chemo-mechanical caries removal. Effects on surrounding tissues and materials

Abstract

AimThe aim of the present thesis was to study surface mediated interactions related to chemo-mechanical caries removal, in particular effects on oral tissues and dental restorative materials.Materials and MethodsFreshly mixed Carisolv® was applied to the oral mucosa of human and rat for 3 min. The soft tissue reactions were evaluated by visual inspection, and biopsies were taken from the rats and examined under light microscopy after histological preparation. Dentine cavities after caries excavation with burrs and Carisolv®, respectively, were chemically characterised with Fourier Transform (FT) Raman spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). A topographical comparison of acid etched dentine cavities after burrs and Carisolv®, respectively, was performed with a Contact Stylus Pofilometer. Furthermore, the surface topography of 3 different types of dental ceramics, a composite resin, a polyacid modified composite resin, and a glass-ionomer material was measured before and after 5, 10, and 20 min exposure to solutions for chemo-mechanical caries removal; topography was performed with Confocal Laser Scanning Profilometry (CLSP), Optical Interferometry, and Atomic Force Microscopy (AFM). AFM was also used to investigate the effect of Carisolv® on salivary films formed on germanium prisms.ResultsNo or only weak inflammatory response was detected on the oral mucosa after direct contact with Carisolv® for 3 min. The dentine cavities after chemo-mechanical caries removal were chemically comparable to the dentine cavities after caries excavation with burrs. After phosphoric acid treatment dentine cavities exhibited a similar surface roughness, independently on whether the caries excavation had been performed with burrs or Carisolv®. Minor changes in the surface topography of the restorative materials investigated were detected after up to 20 min exposure to solutions used for chemo-mechanical caries removal. Five minutes Carisolv® exposure seemed to be sufficient for the removal of salivary films on germanium prisms.ConclusionsChemo-mechanical caries removal can be expected to have minor effects on the inflammatory response of oral mucosa, on the surface chemistry of dentine cavities, and on the surface topography of etched dentine cavities and restorative materials. Furthermore, Carisolv® seems capable of removing salivary films.