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.


METHODS
Rectangular bars of L were made (60 x 6 x 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 x 6 x 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.


CONCLUSIONS
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.
Department of Dental Materials and Prosthodontics, Araraquara Dental School, São Paulo State University - UNESP, São Paulo, Brazil.
Luciano Elias
LE
da Cruz Perez
Ana Lucia
AL
Machado
Sebastião Vicente
SV
Canevarolo
Carlos Eduardo
CE
Vergani
Eunice Teresinha
ET
Giampaolo
Ana Cláudia
AC
Pavarina
D000180:Acrylic Resins / Q000737:chemistry*; D001840:Dental Bonding; D003764:Dental Materials / Q000737:chemistry*; D003819:Denture Bases; D003822:Denture Liners; D003823:Denture Rebasing; D006358:Hot Temperature; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D020366:Methylmethacrylate / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D012826:Silicone Elastomers / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties
D000180:Acrylic Resins; D003764:Dental Materials; D008689:Methacrylates; D011108:Polymers; D012826:Silicone Elastomers; C503430:Tokuso Rebase Fast; C483158:Ufi gel; D020366:Methylmethacrylate; C040291:Lucitone