Curing kinetics of a photo-polymerized dental sealant.
OBJECTIVE
To evaluate the effect of using a variety of light-curing sources on the extent (monomer conversion) and rate of cure of a light-cured dental sealant.


METHODS
Infrared spectroscopy recorded real-time polymerization of a self-cured and a light-cured sealant when the latter was exposed using manufacturer's recommendations [quartz-tungsten-halogen (QTH)] for 20 seconds as well as to other light sources: high intensity QTH, plasma arc light (PAC), and second-generation blue light emitting diode (LED) units. Specimens were heated to 37 degrees C and the degree and rate of conversion were recorded at each second for 300 seconds. Conversion extent and rate were compared among light units as well as to the self-curing product. Five replications for each test condition were performed.


RESULTS
After 300 seconds, self-curing product conversion was equivalent to all light-exposed specimens. The self-cured rate of cure was significantly lower than all light-cured scenarios. The high intensity QTH light provided equivalent conversion as conventional 20-second QTH exposure (control) in only 10 seconds. The PAC light required similar exposure time as conventional QTH treatment. Second-generation blue LED units reached conversion similar to control in only 10 seconds, while one light required only 5 seconds' exposure.
Warnock
Ralph D
RD
Department of Dental Materials, School of Dentistry, The Medical College of Georgia, Augusta 30912-1260, USA.
Rueggeberg
Frederick A
FA
D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry / Q000528:radiation effects; D004867:Equipment Design; D006358:Hot Temperature; D006801:Humans; D007700:Kinetics; D008029:Lighting / Q000295:instrumentation*; D008422:Materials Testing; D010895:Pit and Fissure Sealants / Q000737:chemistry* / Q000528:radiation effects; D011108:Polymers / Q000737:chemistry / Q000528:radiation effects; D013055:Spectrophotometry, Infrared; D013997:Time Factors
D010895:Pit and Fissure Sealants; D011108:Polymers; D017438:Bisphenol A-Glycidyl Methacrylate