Water sorption, solubility and surface roughness of resin surface sealants

Abstract

Surface sealants have been suggested as final glaze of the surface of composite restorations. However, little is known about bulk and surface properties of these materials aiming the long-term preservation of the surface integrity of these restorations. Aim: To evaluate the water sorption, solubility and surface roughness of commercial surface sealants for restorations. Methods: Five disc-shaped specimens (15 mm diameter X 1 mm high) were made from the surface sealants Natural Glaze (DFL) and Permaseal (Ultradent) and were light cured according to the manufacturer's instructions. The specimens were finished with 1500-grit SiC paper. Water sorption (WS) and solubility (SL) were assessed as recommended by the ISO 4049/2000 and were expressed in µg/mm 3 . Surface roughness was evaluated before and after WS and SL, and was expressed in µm as R 1 (before WS and SL) and R 2 (after WS and SL). It was obtained from three parallel measurements along a 4mm length. Data were analyzed using t-test and paired t-test (α=0.05). Results: Water sorption and solubility of Natural Glaze were significantly lower than that of Permaseal (p<0.05). Degradation of the surface sealants did not affect significantly their surface roughness (p>0.05). Conclusions: Surface sealants used in composite restorations undergo hydrolytic degradation; however, this degradation seems not to interfere on surface roughness of these materials.

Tooth whitening recovers the color of pre-stained composites

“…The susceptibility of the composite to percolation of staining substances is related to its chemical composition, which includes the type of monomer, the type of inorganic filler, the used photoinitiator and the quality of the matrix/filler interface 14 . It is also modulated by its degree of conversion and network characteristics, since a low degree of conversion leads to degradation of the polymer network and release of byproducts 6,12,15,16 . The nanocomposite used in this study is recommended to both anterior and posterior restorations and has been characterized elsewhere 17 , revealing a degree of conversion of 46% on the top surface and of 38% on the bottom surface of a 2 -mm thick specimen.…”

“…No significant change in surface roughness was observed throughout the treatment conditions, in either group. Expectations were that degradation would lead to solubilization of non-converted monomers, oligomers, catalysts, silane and other by-products, which would expose and dislodge filler particles, increasing surface roughness 6,12 . This would lead to a more porous surface rising the percolation way for either the staining solution or the whitener.…”

“…Intrinsic factors involve the hydrolytic degradation and release of constituents, while extrinsic factors involve the incorporation of pigments by staining substances from the diet 4 . Hydrolytic degradation is inherent to dimethacrylate-based composites in contact with a wet environment, leading ultimately to a more porous restoration 6 . Although the increase of porosity of the restoration makes it more prone to staining, water diffusion alone revealed being insufficient to lead to significant, visible color change of a composite restoration 4 .…”

Shear Bond Strength of Bisphenol a-Glycidyl Methacrylate Adhesive Resin After Application of Eucalyptus Oil Before Debonding Metallic Orthodontic Bracket

“…Solubility is the ability of a polymer to dissolve in a solvent. The solubility of a polymer is influenced by its solubility parameter from both the solvent and the polymeric material, duration of immersion, temperature, and the crosslink nature of the resin matrix and the filler [9,10]. Resin dissolution occurs when the resin gets in contact with the solvents that present a close solubility parameters [11].…”

Comparative Evaluation of the Effect of Surface Polishing of a Glaze/composite Sealant and Different Polishing Systems on Surface Roughness of Three Composite Resin Type

“…Finished and coated surfaces of composite resins restoration were previous analyze by Biazuz & col. [19] regarding water absorption, solubility and surface roughness. Positive results were obtained, water absorption and solubility did not increase the surface roughness, which, according to the authors of the study, demonstrates the possibilities of their use in the long-term maintenance of the surface quality of composite resin restorations.…”