Evaluation of Vickers hardness of different types of acrylic denture base resins with and without glass fibre reinforcement.
OBJECTIVE
To evaluate the Vickers hardness of different acrylic resins for denture bases with and without the addition of glass fibres.


BACKGROUND
It has been suggested that different polymerisation methods, as well as the addition of glass fibre (FV) might improve the hardness of acrylic.


METHODS
Five types of acrylic resin were tested: Vipi Wave (VW), microwave polymerisation; Vipi Flash (VF), auto-polymerisation; Lucitone (LT), QC20 (QC) and Vipi Cril (VC), conventional heat-polymerisation, all with or without glass fibre reinforcement (GFR) and distributed into 10 groups (n = 12). Specimens were then submitted to Vickers hardness testing with a 25-g load for 30 s. All data were submitted to anova and Tukey's HSD test.


RESULTS
A significant statistical difference was observed with regard to the polymerisation method and the GFR (p < 0.05). Without the GFR, the acrylic resin VC presented the highest hardness values, and VF and LT presented the lowest. In the presence of GFR, VC resin still presented the highest Vickers hardness values, and VF and QC presented the lowest.


CONCLUSIONS
The acrylic resin VC and VW presented higher hardness values than VF and QC resins. Moreover, GFR increased the Vickers hardness of resins VW, VC and LT.
Department of Prosthodontics and Periodontics, Piracicaba Dental School, Campinas State University, São Paulo, Brazil. ana_goergen@yahoo.com.br
Ana Paula
AP
Farina
Doglas
D
Cecchin
Rodrigo Gonçalves
RG
Soares
André Luís
AL
Botelho
Jessica Mie Ferreira Koyama
JM
Takahashi
Marcelo Oliveira
MO
Mazzetto
Marcelo Ferraz
MF
Mesquita
D000180:Acrylic Resins / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D003819:Denture Bases; D004853:Epoxy Resins / Q000737:chemistry; D005898:Glass / Q000737:chemistry*; D006244:Hardness; D006358:Hot Temperature; D006801:Humans; D008422:Materials Testing; D008872:Microwaves; D058105:Polymerization; D012821:Silanes / Q000737:chemistry; D013499:Surface Properties
D000180:Acrylic Resins; D003764:Dental Materials; D004853:Epoxy Resins; D012821:Silanes; C009753:fiberglass; C539101:vipi cril; C539102:vipi wave; C040291:Lucitone