Film thicknesses of recently introduced luting cements.
BACKGROUND
A luting cement must maintain a minimum film thickness over a sufficient period of time to allow seating of indirect restorations. The performance of newer luting cements in this regard has not been evaluated.


OBJECTIVE
The purpose of this study was to compare the film thicknesses of 6 luting cements, 2 resin-modified glass ionomer (FujiCEM and RelyX Luting Plus), 2 composite resin (Panavia 21 and RelyX ARC), and 2 self-adhesive resin (Maxcem and RelyX Unicem) cements, over 3 minutes.


METHODS
The film thickness (microm) of each cement (n=7) was determined at room temperature at 1, 2, and 3 minutes after the start of mixing, according to the testing method set forth in ISO Standard 9917. Means of all cements were compared at the 2-minute interval, and means at the 1- and 3-minute intervals for each were compared to the mean for the same cement at 2 minutes, using 1-way analyses of variance (ANOVA) and Tukey-Kramer multiple comparison tests (alpha=.05).


RESULTS
Except for 1 resin-modified material at 3 minutes, a point beyond its specified working time, all materials produced film thicknesses under 30 microm at 3 minutes and under 26 microm at 2 minutes.


CONCLUSIONS
All of the materials tested meet the ISO standard of 25-microm maximum film thickness for up to 2 minutes after mixing.
Kious
Andrew R
AR
Department of Oral Rehabilitation, School of Dentistry, Medical College of Georgia, Augusta, Ga 30912-1260, USA. akious@mail.mcg.edu
Roberts
Howard W
HW
Brackett
William W
WW
D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D018772:Dental Marginal Adaptation; D005899:Glass Ionomer Cements / Q000737:chemistry; D010710:Phosphates / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D012212:Rheology; D013997:Time Factors
D003188:Composite Resins; C542393:FujiCEM; D005899:Glass Ionomer Cements; C515955:Maxcem; C093719:Panavia TPN-S; D010710:Phosphates; D011109:Polymethacrylic Acids; C483701:Rely X Unicem; C462240:RelyX ARC; D019279:Resin Cements; C084550:Vitremer; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate