Effects of microwave polymerization and water-bath heat polymerization on accuracy and flexural strength of denture base resin
10.3969/j.issn.1673-8225.2009.38.027
- VernacularTitle:微波和水浴聚合方法对热固化聚甲基丙烯酸甲酯树脂基托义齿精度和抗弯强度的影响
- Author:
Xue WANG
;
Lin ZHU
;
Yan WANG
;
Yubao DING
- Publication Type:Journal Article
- From:
Chinese Journal of Tissue Engineering Research
2009;13(38):7528-7530
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE: To evaluate the effect of microwave polymerization and water-bath heat polymerization on accuracy and flexural strength of denture base resin. METHODS: Ten maxillary complete dentures were prepared and divided into microwave polymerization and water-bath heat polymerization groups according to random number table, with 5 dentures in each group. In the microwave polymerization group, the dentures were heated for 9 minutes with 40% firepower, natural cooled, the pressure of flasking at 4.5 kg/mm~2. In the water-bath heat polymerization group, the temperature increased from room to 70℃, sustained for 1.5 hours, then rise to 100℃ for 0.5 hour. The dentures were maintained at 25℃ thermostatic water bath for a week. The denture base, as well as standard cast was cut down at posterior border of the second molar. Dimensional accuracy between the posterior border of upper complete denture and standardized cast at five different positions was measured by digital microscope. Specimens with 64 mm× 10 mm×2.5 mm were made for measuring flexural strength.RESULTS: ①The posterior border gaps between the upper complete denture and standardized cast was (141±78) urn and (147±74) μm cured by microwave polymerization and water-bath heat polymerization, which has no statistical difference. The flexural strength of denture base resin cured by the microwave polymerization and water-bath heat polymerization was (81.60±14.04) MPa and (84.24±17.65) MPa, and there was no statistical difference (P > 0.05). CONCLUSION: There is no significantly difference in the accuracy and flexural strength cured by microwave polymerization and by water-bath heat polymerization, but the microwave polymerization takes shorter time than that by water-bath heat polymerization.
