Bond strength of hard chairside reline resins to a rapid polymerizing denture base resin before and after thermal cycling

Abstract

Purpose:This study assessed the shear bond strength of 4 hard chairside reline resins (Kooliner, Tokuso Rebase Fast, Duraliner II, Ufi Gel Hard) to a rapid polymerizing denture base resin (QC-20) processed using 2 polymerization cycles (A or B), before and after thermal cycling.Materials and Methods:Cylinders (3.5 mm x 5.0 mm) of the reline resins were bonded to cylinders of QC-20 polymerized using cycle A (boiling water–20 minutes) or B (boiling water; remove heat-20 minutes; boiling water–20 minutes). For each reline resin/polymerization cycle combination, 10 specimens (groups CAt e CBt) were thermally cycled (5 and 55 °C; dwell time 30 seconds; 2,000 cycles); the other 10 were tested without thermal cycling (groups CAwt ad CBwt). Shear bond tests (0.5 mm/min) were performed on the specimens and the failure mode was assessed. Data were analyzed by 3-way ANOVA and Newman-Keuls post-hoc test (α=.05).Results:QC-20 resin demonstrated the lowest bond strengths among the reline materials (P<.05) and mainly failed cohesively. Overall, the bond strength of the hard chairside reline resins were similar (10.09±1.40 to 15.17±1.73 MPa) and most of the failures were adhesive/cohesive (mixed mode). However, Ufi Gel Hard bonded to QC-20 polymerized using cycle A and not thermally cycled showed the highest bond strength (P<.001). When Tokuso Rebase Fast and Duraliner II were bonded to QC-20 resin polymerized using cycle A, the bond strength was increased (P=.043) after thermal cycling.Conclusions:QC-20 displayed the lowest bond strength values in all groups. In general, the bond strengths of the hard chairside reline resins were comparable and not affected by polymerization cycle of QC-20 resin and thermal cycling.

Effect of different solutions on color stability of acrylic resin-based dentures

“…27,28 Moreover, the components used for chemical activation in addition to thermal activation, contained in the short-cycle resins, may be responsible for the results shown by the QC resin. 29 These results are in agreement with those by Hersek et al, 20 who evaluated the color stability of acrylic resins in three colorants used in food and verified that LU followed by QC presented the greatest color changes.…”

“…1,[20][21][22]29 The dark pigment of W and its low pH can cause drastic staining, negatively affecting the surface integrity by softening the matrix. 20 In this study, only OC did not show a statistically significant color change when immersed in W (Table 6).…”

Shear Bond Strength of Two Chemically Different Denture Base Polymers to Reline Materials

“…It was also stated that Eclipse can be relined using the same Eclipse material as well as with other conventional autopolymerized materials. So far, no study has reported on the bond strength of Eclipse as compared to many reports available with PMMA denture base polymer 8,13,14–17 . This study showed that for all reline materials excluding Eclipse reline, the shear bond strengths to PMMA were higher than the strength of corresponding reline materials to UDMA polymer.…”

“…As adhesion depends on the penetration of polymerizable monomer of reline material into the denture network, 6 higher molecular weight of IBMA (isobutyl methacrylate) monomer available in Kooliner might have limited the monomer penetration 6,9,14 . In contrast, Neppelenbroek et al 17 found that Kooliner reline showed mixed modes of failure to PMMA base. The denture surface, however, was treated with MMA monomer, which might explain the improved bonding 5 …”

Effect of Net Fiber Reinforcement Surface Treatment on Soft Denture Liner Retention and Longevity

“…In vitro simulation of intraoral changes using thermal cycling can greatly affect the mechanical integrity of the liner/denture interface, initiating crack propagation; 28,29 however, the effect of thermocycling is inconclusive and material dependent 9 . It may increase or decrease bond strength 19,28,30–34 …”