Surface morphology and mechanical properties of conventional and self-adhesive resin cements after aqueous aging

Abstract

The stable long-term performance of resin cement under oral environmental conditions is a crucial factor to obtain a satisfactory success of the allceramic dental restoration. Objective: This study aimed at evaluating and comparing the surface morphology and mechanical property of conventional and self-adhesive resin cement after aqueous aging. Materials and Methods: Disc-shaped specimens of 3 conventional (C1: Multilink N, C2: Duolink, C3: Nexus 3) and 3 self-adhesive (S1: Multilink Speed, S2: Biscem, S3: Maxcem) types of resin cements were subjected to irradiation. After 24 h, the Knoop microhardness of each resin cement was evaluated. The specimens were immersed separately in distilled water and maintained at 37°C. A total of 5 specimens of each resin cement were collected at the following time intervals of immersion: 1, 6, 12 and 18 months. The samples were used to evaluate the Knoop parameters of microhardness, sorption and solubility. The surface morphology of the specimens after 18 months of immersion was observed by scanning electron microscopy. The sorption and solubility data were analyzed by two-way ANOVA. The Knoop microhardness was tested by the ANOVA repeated measures (P<0.05). Results: The sorption and solubility parameters of C1 and S1 exhibited significant fluctuations during the aqueous aging. The hardness of the S1 and S2 specimens decreased significantly after an 18-month water immersion. The S1, S2 and S3 specimens indicated higher filler exposure and stripping and apparent pores and cracks compared to specimens C1, C2 and C3, respectively. Conclusion: The surface of selfadhesive resin cements is more susceptible to aqueous damage than that of the conventional resin cements.

In Vitro Evaluation of Physical and Mechanical Properties of Light-Curing Resin Cement: A Comparative Study

“…3 An important aspect to consider is that the resin cement film around the margins of the restorations is often located close to the free gingival margin or gingival sulcus, [4][5][6] a susceptible area of sorption, hydrolysis, and dynamic fatigue which may lead to polymer degradation. 7 Resin-based luting cement is methacrylate monomers with small filler contents and a photoinitiator. 5,6 In general, dental polymers' networks are not chemically stable and water impermeable.…”

“…These monomers have been shown to absorb moisture, which is a critical property due to the adverse effects on hydrolytic stability. 8 This phenomenon may result in material discoloration, mechanical deterioration, degradation of filler-matrix interface, polymer swelling, weakening of the polymer network, 7,8 and stress-induced degradation of the resin cement leading to debonding or fracture of the ceramic restoration. 5,8 Many factors can influence the coefficient of water diffusion between the polymer network, including filler content and the resin matrix volume.…”

Cytotoxicity of Self-Adhesive Resin Cements on Human Periodontal Ligament Fibroblasts

“…Many studies shown RU, ME, and MS without light irradiation have lower polymerization degree or hardness than them with light irradiation [14][15][16][17][18], plus their high values of water absorption, solubility, and water expansion stress [6][7][8][9][10], which might lead to a series of changes in extract solution of self-adhesive resin cements. In this study, more distinct absorption peaks and higher absorption peak value occurred in the extract solution of each self-adhesive resin cement without light irradiation.…”

“…The concentration of the acidic monomers in the selfadhesive resin cements should be sufficiently high to achieve an acceptable bonding to the dentin and enamel; meanwhile, as the acid functionality is consumed through reaction with calcium on the tooth and a variety of metal oxides from the ion-leachable filler, these materials become more hydrophobic [3]. However, studies have indicated that most selfadhesive resin cements exhibited higher sorption and solubility than conventional resin cements [6][7][8][9][10]. The excessive hydrophilic character of self-adhesive resin cement can cause swelling that in turn can compromise surface dimensional stability [9][10][11][12].…”

“…However, studies have indicated that most selfadhesive resin cements exhibited higher sorption and solubility than conventional resin cements [6][7][8][9][10]. The excessive hydrophilic character of self-adhesive resin cement can cause swelling that in turn can compromise surface dimensional stability [9][10][11][12].…”