Solubility, salivary sorption and degree of conversion of dimethacrylate‐based polymeric matrixes

Abstract

This study investigated the relationship between the solubility, salivary sorption, and degree of conversion of dimethacrylate-based polymeric matrixes. Six polymeric matrixes produced by mixing bis-GMA, TEGDMA and UDMA dimethacrylate monomers were studied. Photoactivation was induced by camphoroquinone/ethyl N,N-dimethyl-4-aminobenzoate. The specimens were light-cured using an irradiance of 850 mW/cm(2) for 20 s. The solubility and sorption (microg/mm(3)) were measured after immersion in artificial saliva (neutral pH) for 7 days. The degree of conversion (%) was obtained by using a FT-IR spectrometer equipped with an attenuated total reflectance crystal (ATR). The degree of conversion varied from 39.15 +/- 6.30 to 65.57+/- 4.80, and was influenced by the viscosity of the monomers present in the polymeric matrixes. The solubility of polymeric matrixes varied between 13.64 +/- 0.39 and 25.08 +/- 0.83, and was strongly influenced by the degree of conversion (Pearson, r = -0.9587, p < 0.01). No correlation was found between salivary sorption and the degree of conversion (p = 0.3918). Salivary sorption was only dependent on the chemical and physical structures of the monomers presented in the polymeric matrixes.

Influence of extended light exposure curing times on the degree of conversion of resin-based pit and fissure sealant materials

“…The results of the present study were in accordance with those of previous studies (Aguilar et al, 2007;Musanje et al, 2009;Silva et al, 2008). Moreover, a previous study demonstrated that an increased amount of triethylene glycol dimethacrylate (TEGDMA) in an experimental dimethacrylate-based polymer matrix led to an increased conversion of the monomer (Goncalves et al, 2008). Similarly, in the present study, the flowable composite showed a higher DC due to the increased TEGDMA content.…”

The influence of mouthrinses and simulated toothbrushing on the surface roughness of a nanofilled composite resin

“…4 The degradation of resin composites is a complex mechanism that depends on the characteristics of the composite, such as the size, 17 volume and type of inorganic filler, 2,4,18 matrix composition, and degree of conversion. 19 The most likely explanation for degradation is the presence of nanosized particles (5-20 nm) throughout the resin matrix, 7 which results in less space between the particles, and ultimately more protection of the softer resin matrix 4,20 and less filler plucking, 20 compared with other types of resins. This leads to lower resin porosity 21 and improved abrasion resistance of the material.…”

“…Monomers like UDMA, Bis-GMA, and TEGDMA contain polar groups such as -OH-, -O-, and -NH-. These groups increase the material's hydrophilicity, 19 probably making it more prone to salivary sorption; 17 however, these factors cannot be considered to influence this study, since they were standardized for all groups.…”

Characterization of an experimental resin composite organic matrix based on a tri-functional methacrylate monomer

“…Most probably, this behavior was influenced by the similarity in DC% among matrixes (Table 2). In fact, previous studies have already shown that solubility correlates well with degree of conversion 4,28) .…”

“…In general, resin composites comprise three phases: a organic matrix formed by a mix of bi-functional methacrylate monomers, inorganic filler particles and a silane-coupling agent that chemically bonds the organic matrix to the filler particles. These three phases strongly influence the materials' properties 4,5) . Irrespective of recent and important developments 1,2) , organic matrixes of resin composites are still composed of bi-functional methacrylate momomers 6) .…”