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Denture Base Acrylic Resin (denture_base + acrylic_resin)

Distribution by Scientific Domains
Medical Sciences100%

Selected Abstracts

Effect of reline material and denture base surface treatment on the impact strength of a denture base acrylic resin

GERODONTOLOGY, Issue 1 2010
Luciano Elias Da Cruz Perez
doi:10.1111/j.1741-2358.2009.00292.x Effect of reline material and denture base surface treatment on the impact strength of a denture base acrylic resin Objective:, In this study, the effect of relining and surface treatment on the impact strength (IS) of a heat-polymerising denture base acrylic resin (Lucitone 550-L) was evaluated. Materials and methods:, Rectangular bars of L were made (60 × 6 × 2 mm) and relined (2 mm) with the relining resins Ufi Gel Hard (UH) and Tokuso Rebase Fast (TR). Specimens relined with L and intact L, TR and UH specimens were also made (60 × 6 × 4 mm), for comparison. Before relining, the L surface was left untreated or wetted with methyl methacrylate monomer and/or the bonding agents (BA) supplied by manufacturers of the reline resins. V-notches were machined at the midpoint of the length of all specimens. The notches were made either across the width (Nw) or across the thickness of the specimens (Nth). The Charpy impact test was performed using a 0.5-J pendulum, which had been specially designed and constructed. Data were analysed separately for each notch position using one-way analysis of variance and Tukey honestly significant difference post - hoc test (p = 0.05). Results:, The IS of L was similar to that of L/L. For the Nw notch, treating the denture base L with TR BA and relining with TR reline material produced the highest IS. Conclusion:, The IS of specimens made from heat polymerising acrylic resin Lucitone 550 was increased after relining using the hard chairside reline resin TR with its proprietary BA. [source]

Effect of Microwave Disinfection Procedures on Torsional Bond Strengths of Two Hard Chairside Denture Reline Materials

JOURNAL OF PROSTHODONTICS, Issue 6 2006
Ana Lucia Machado DDS
Purpose: This study evaluated the potential effects of denture base resin water storage time and an effective denture disinfection method (microwave irradiation at 650 W for 6 minutes) on the torsional bond strength between two hard chairside reline resins (GC Reline and New Truliner) and one heat-polymerizing denture base acrylic resin (Lucitone 199). Materials and Methods: Cylindrical (30 × 3.9 mm) denture base specimens (n= 160) were stored in water at 37°C (2 or 30 days) before bonding. A section (3.0 mm) was removed from the center of the specimens, surfaces prepared, and the reline materials packed into the space. After polymerization, specimens were divided into four groups (n= 10): Group 1 (G1),tests performed after bonding; Group 2 (G2),specimens immersed in water (200 ml) and irradiated twice (650 W for 6 minutes); Group 3 (G3),specimens irradiated daily until seven cycles of disinfection; Group 4 (G4),specimens immersed in water (37°C) for 7 days. Specimens were submitted to a torsional test (0.1 Nm/min), and the torsional strengths (MPa) and the mode of failure were recorded. Data from each reline material were analyzed by a two-way analysis of variance, followed by Neuman-Keuls test (p= 0.05). Results: For both Lucitone 199 water storage periods, before bonding to GC Reline resin, the mean torsional strengths of G2 (2 days,138 MPa; 30 days,132 MPa), G3 (2 days,126 MPa; 30 days,130 MPa), and G4 (2 days,130 MPa; 30 days,137 MPa) were significantly higher (p < 0.05) than G1 (2 days,108 MPa; 30 days,115 MPa). Similar results were found for Lucitone 199 specimens bonded to New Truliner resin, with G1 specimens (2 days,73 MPa; 30 days,71 MPa) exhibiting significantly lower mean torsional bond strength (p < 0.05) than G2 (2 day,86 MPa; 30 days,90 MPa), G3 (2 days,82 MPa; 30 days,82 MPa), and G4 specimens (2 days,78 MPa; 30 days,79 MPa). The adhesion of both materials was not affected by water storage time of Lucitone 199 (p > 0.05). GC reline showed a mixed mode of failure (adhesive/cohesive) and New Truliner failed adhesively. Conclusions: Up to seven microwave disinfection cycles did not decrease the torsional bond strengths between the hard reline resins, GC Reline and New Truliner to the denture base resin Lucitone 199. The effect of additional disinfection cycles on reline material may be clinically significant and requires further study. [source]