Curing potential of dual-polymerizable resin cements in simulated clinical situations.
BACKGROUND
Little is known about the ability of dual-polymerizable resin cements to polymerize when they are used in various clinical scenarios.


OBJECTIVE
This study was conducted to determine whether any of 6 commercially available dual-polymerizable resin cements should be classified as an "all-purpose" resin cement.


METHODS
. Chemical conversion values (C=C converted to C-C, or the extent of the curing reaction) of 6 commercially available dual-polymerizable resin cements were determined with infrared spectroscopy in 5 clinically relevant scenarios. Scenarios included: using each cement in a dual-polymerizable mode (mixing of 2 pastes); light polymerizing curing through Mylar sheets (dual-Mylar), which served as the control; light polymerizing through 3-mm porcelain (dual-3 mm); and no exposure to light (dual-no light). The single-component light-polymerizable product was also tested as follows: exposed directly through Mylar (light-Mylar) or exposed through 3 mm of porcelain (light-3 mm). Results. For each product, dual-Mylar treatment yielded the highest conversion value of all treatments (control for each product). For all products, dual-3 mm conversion was at least 97% of control and equivalent to control, with the exception of Lute-It!. Dual-no light conversion was less than control treatment but at least 86% of control for all products except for Variolink II (62% of control). For all products in dual-no light mode, except Choice and Variolink II, conversion was at least equal to the light-Mylar values. Only 1 product (Variolink II) did not demonstrate increased conversion values for dual-Mylar compared with light-Mylar treatments. For most other products (Calibra, Insure, and Lute-It!), conversion values for light-3 mm were significantly less than for light-Mylar. Conversion values for Nexus, Choice, and Variolink II were equivalent between light-Mylar and light-3 mm treatments.


CONCLUSIONS
The choice of a dual-polymerizable cement should be based on its intended use because not all products polymerize adequately in every clinical situation. Although no cement met the stated criteria for an "all-purpose" cement, those tested did produce a range of product-specific results.
Caughman
W F
WF
School of Dentistry, Medical College of Georgia, Augusta, GA, 30912-1260, USA. fcaughma@mail.mcg.edu
Chan
D C
DC
Rueggeberg
F A
FA
D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D008027:Light; D008422:Materials Testing; D011108:Polymers / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D018709:Statistics, Nonparametric; D013674:Technology, Dental
C433205:Calibra; C086628:Choice resin cement; C096479:Insure Cement; C433207:Lute-It; C433206:Nexus; D011108:Polymers; D011109:Polymethacrylic Acids; D019279:Resin Cements; C103502:Variolink; D017438:Bisphenol A-Glycidyl Methacrylate