The effect of light-curing modes on the microleakage of cervical resin composite restorations.
OBJECTIVE
This study investigated the effect of light-curing modes on the microleakage of cervical resin composite restorations.


METHODS
Eighty wedge-shaped cervical cavities, C-factor approximately 1.3, were prepared on the labial surface of bovine incisors. The cavities were treated with a two-step experimental self-etching primer adhesive system containing an antibacterial monomer (ABF), according to the manufacturer's instructions, and filled with a single increment of a hybrid resin composite. The restorations were allocated randomly into four groups of 20: Group 1-the restorations were light-cured for 40 s with a conventional light-curing unit (New Light VL-II); Group 2-the restorations were cured with Candelux using a two-step mode; Group 3-the restorations were cured with Astralis 7 using a ramping mode; Group 4-the restorations were light-cured for 3 s with a plasma arc light-curing unit (Wave Light). Half of the specimens from each group were subjected to thermocycling (5-60 degrees C, 15 s dwell time, 5000 cycles) prior to immersion in 0.5% basic fuchsin. The teeth were sectioned and the degrees of dye penetration were scored. The data were analyzed with either the Kruskal-Wallis test or the Mann-Whitney U-test (p < 0.05)


RESULTS
No significant differences were found in the microleakage scores among the light-curing modes used. The restorations tended to display more microleakage when they were subjected to thermocycling, but the differences were not statistically significant.


CONCLUSIONS
These findings suggest that light-curing modes may have no effect on the microleakage of cervical cavities with a small C-factor, as is the case in this study.
Division of Cariology, Department of Developmental and Reconstructive Medicine, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1, Sakamoto, Nagasaki 852-8588, Japan. kubo@net.nagasaki-u.ac.jp
Shisei
S
Kubo
Hiroaki
H
Yokota
Haruka
H
Yokota
Yoshihiko
Y
Hayashi
D000818:Animals; D002417:Cattle; D004396:Coloring Agents; D003188:Composite Resins / Q000528:radiation effects*; D003748:Dental Equipment; D003763:Dental Leakage / Q000175:diagnosis / Q000209:etiology*; D018772:Dental Marginal Adaptation; D003793:Dental Restoration, Permanent / Q000009:adverse effects* / Q000379:methods; D006219:Halogens; D008027:Light; D008689:Methacrylates / Q000528:radiation effects*; D011108:Polymers / Q000737:chemistry; D018709:Statistics, Nonparametric; D013674:Technology, Dental / Q000379:methods; D019237:Tooth Cervix; D014978:Xenon
C112828:Clearfil AP-X; D004396:Coloring Agents; D003188:Composite Resins; D006219:Halogens; D008689:Methacrylates; D011108:Polymers; D014978:Xenon