Effects of light curing modes and ethanol-wet bonding on dentin bonding properties.
OBJECTIVE
This study explored the effects of different light curing modes and ethanol-wet bonding on dentin bonding strength and durability.


METHODS
A total of 54 molars were randomly divided into three groups: Single Bond 2, Gluma Comfort Bond, and N-Bond. Based on the three light-curing modes and presence or absence of ethanol pretreatment, the samples were assigned to six subgroups: high-light mode, ethanol pretreatment+high-light mode, soft-start mode, ethanol pretreatment+soft-start mode, standard mode, and ethanol pretreatment+standard mode. All samples were bonded with resin based on the experimental groups. After 24 h and 6 months of water storage, a universal testing machine was used to measure microtensile bond strength. Scanning electron microscopy (SEM) was applied to observe mixed layer morphology.


RESULTS
The 24-h and 6-month microtensile bond strengths of the ethanol pretreatment groups were significantly higher than those of the non-ethanol pretreatment groups at the same light modes (P<0.05). With or without ethanol pretreatment, the microtensile bond strengths of the high-light modes were significantly lower than those of the soft-start modes and standard modes (P<0.05). The microtensile bond strengths of samples from the 6-month water storage group significantly decreased compared with those of samples from the 24-h water storage group (P<0.05). The soft-start groups and standard groups formed better mixed layers than the high-light mode groups, whereas the ethanol pretreatment groups formed more uniform mixed layers than those without ethanol pretreatment.


CONCLUSIONS
Ethanol-wet bonding technique, soft-start, and standard modes could improve dentin bonding properties.
School and Hospital of Stomatology, Jilin University, Changchun 130021, China.|Jilin Provincial Key Laboratory of Tooth Development and Remodeling, Changchun 130021, China.
Mu-Zi
MZ
Li
School and Hospital of Stomatology, Jilin University, Changchun 130021, China.
Jin-Rui
JR
Wang
School and Hospital of Stomatology, Jilin University, Changchun 130021, China.|Jilin Provincial Key Laboratory of Tooth Development and Remodeling, Changchun 130021, China.
Hong
H
Liu
School and Hospital of Stomatology, Jilin University, Changchun 130021, China.
Xia
X
Wang
School and Hospital of Stomatology, Jilin University, Changchun 130021, China.
Kang
K
Gan
School and Hospital of Stomatology, Jilin University, Changchun 130021, China.
Xiu-Ju
XJ
Liu
School and Hospital of Stomatology, Jilin University, Changchun 130021, China.
De-Li
DL
Niu
School and Hospital of Stomatology, Jilin University, Changchun 130021, China.
Xiao-Qing
XQ
Song
D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D055117:Curing Lights, Dental; D001840:Dental Bonding / Q000379:methods*; D003799:Dental Stress Analysis; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D000431:Ethanol / Q000737:chemistry*; D006801:Humans; D008027:Light; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008963:Molar / Q000473:pathology*; D013499:Surface Properties; D013718:Tensile Strength; D014867:Water / Q000737:chemistry
D017220:Dentin-Bonding Agents; C445021:Gluma Comfort Bond; C115612:single bond; D014867:Water; D000431:Ethanol; D017438:Bisphenol A-Glycidyl Methacrylate
Bonding strength; Ethanol-wet bonding; Light curing mode; Scanning electron microscopy (SEM); Soft-start