11. Effect of ultrasonic excitation on the porosity of glass ionomer cement: a scanning electron microscope evaluation.
Coldebella CR, Santos-Pinto L, Zuanon AC.
Department of Orthodontics and Pediatric Dentistry, Araraquara Dental School, São Paulo State University, Rua Humaitá, 14801-903 Araraquara, SP, Brazil. crcoldebella@yahoo.com.br
Abstract
BACKGROUND:
Ultrasonic excitation (US) was applied to glass ionomer cement (GIC) during early set time to increase the advantageous properties of this material.
PURPOSE:
The aim of this in vitro study was to assess the inner porosity of GIC after US.
STUDY DESIGN:
A total of 16 specimens, for each material, were prepared from high-viscosity GIC Fuji IX GP, Ketac Molar, and Ketac Molar Easymix. Half of these specimens (n = 8) received 30 s of US during the initial cement setting. After completion of the material setting, specimens were fractured and observed by scanning electronic microscopy to quantitatively assay porosity inside the material using Image J software.
RESULTS:
Statistical data analysis revealed that US reduced the porosity for all tested materials (P ≤ 0.05). The following reductions (expressed in percentages) were achieved: Fuji IX–from 3.9% to 2.8%; Ketac Molar Easy Mix–from 4.4% to 2.6%, and Ketac Molar–from 2.4% to 1.6%.
CONCLUSION:
Under the tested conditions, US was an effective method for porosity reduction inside the material.
© 2010 Wiley-Liss, Inc.
PMID: 21181710 [PubMed – indexed for MEDLINE] 1. Microsc Res Tech. 2011 Jan;74(1):54-7. doi: 10.1002/jemt.20873.