The strength of International research collaborations
Bond strength of resin cements to ceramics
Micro shear bond strength of a dual cure resin and self-adhesive phosphoro-resin cement were compared on four different porcelains. The porcelain firing and bonding was performed by the collaborators from Brazil while testing and SEM fracture evaluations were performed at VCU. The initial evaluation was of short term bond strengths following storage in water for two weeks. The results of this showed there were significant differences between the bond strengths for different combinations of porcelain and cements. The dual cure resin cement measured significantly lower in bond strength than the self-adhesive cement for all four porcelains.
In the second year of the collaboration the team extended the time in water before testing to 1 year and found that the dual cure resin cement bond strength to the different porcelains decreased the most with the storage (ie. least stable bonds) while two of the self-adhesive phosphoro-cement bond porcelain combinations did not significantly change with time in water (ie. most stable bonds).
This June, the team developed different surface treatments of the porcelain to see if they would provide a benefit to bond strength and stability. They treated the control group as in previous testing using hydrofluoric acid etch, followed by a silane coupling agent. This group was compared to a second group treated with hydrofluoric acid followed by ionizing plasma cleaning and a third group where plasma treatment was performed after the control treatment. All the tests were after the short time in water ie two weeks. The team will test these treatments after aging in water for one year in June 2014.
To date this work has produced three abstracts presented at the South American Division of the IADR 2011, IADR Seattle 2013 and 5th International Conference on Adhesive Dentistry 2013 and a publication in RSBO http://www.redalyc.org/pdf/1530/153023704010.pdf.
This collaboration was the first between VCU and Univille University and the possibility for a University wide collaboration agreement is being explored. This would allow the exchange of students and faculty for short periods. This university wide collaboration is being explored by Kim Isringhausen as Director of Community Outreach for the Dental School with VCU Global Education Office with the support of the Dean of the School of Dentistry, Dr Sarrett.
Categories Research