Polymerization time for a microwave-cured acrylic resin with multiple flasks
Open Access
- 1 March 2004
- journal article
- Published by FapUNIFESP (SciELO) in Brazilian Oral Research
- Vol. 18 (1) , 23-28
Abstract
This study aimed at establishing the polymerization time of a microwave-cured acrylic resin (AcronTM MC), simultaneously processing 2, 4, and 6 flasks. Required time was measured according to the parameters: monomer release in water, Knoop hardness, and porosity. Samples were made with AcronTM MC in different shapes: rectangular (32 x 10 x 2.5 mm) for monomer release and porosity; and half-disc (30 mm in diameter x 4 mm in height) for Knoop hardness. There were four experimental groups (n = 24 per group): G1) one flask (control); G2) two flasks; G3) four flasks, and G4) six flasks. At first, polymerization protocol was similar for all groups (3 min/450 W). Time was then adjusted for G2, G3, and G4, based on monomer release evaluation in the control group, obtained by spectrophotometer Beckman DU-70, with emitting wave of 206 nm. Knoop hardness test was performed using a Shimadzu HMV 2000 hardness tester, and 10 indentations were performed on each specimen's surface. Porosity was assessed after specimens were immersed in black ink and the pores counted in a microscope. Results showed that the complete polymerization of the resin occurred in 4.5 min for two flasks (G2); 8.5 min for four flasks (G3); and 13 min for six flasks (G4), all with 450 W. Statistical analysis revealed that the number of flasks does not interfere with polymerization, Knoop hardness, and porosity of the resin. Results showed that polymerization of microwave-curing resin with more than one flask is a viable procedure, as long as polymerization time is adjusted.Keywords
This publication has 11 references indexed in Scilit:
- Microwave‐cured acrylic resins and silicone–gypsum moulding techniqueJournal of Oral Rehabilitation, 2001
- Degree of conversion in denture base materials for varied polymerization techniques 1Journal of Oral Rehabilitation, 2000
- Residual monomer content and its release into water from denture base materialsDental Materials, 1995
- Processing dentures using a microwave techniqueJournal of Oral Rehabilitation, 1994
- Effect of the curing cycle on residual monomer levels of acrylic resin denture base polymersJournal of Dentistry, 1992
- Porosity of denture resin cured by microwave energyThe Journal of Prosthetic Dentistry, 1991
- A method of determining residual monomer in acrylic resin using methyl ethyl ketoneAustralian Dental Journal, 1990
- The use of microwave energy for processing acrylic resinsThe Journal of Prosthetic Dentistry, 1989
- A comparison of denture base acrylic resins polymerised by microwave irradiation and by conventional water bath curing systemsDental Materials, 1988
- Loss into water of residual monomer from autopolymerizing dental acrylic resinBiomaterials, 1982