Effect of multiple coatings of one-step self-etching adhesive on microtensile bond strength to primary dentin.
OBJECTIVE
To investigate the effect of multiple coatings of the one-step self-etching adhesive on immediate microtensile bond strength to primary dentin.


METHODS
Twelve caries-free human primary molars were randomly divided into 2 groups with 6 teeth each. In group 1, each tooth was hemisected into two halves. One half was assigned to control subgroup 1, which was bonded with a single-step self-etching adhesive according to the manufacturer's instructions; the other half was assigned to experimental subgroup 1 in which the adhesive was applied three times before light curing. In group 2, the teeth were also hemisected into two halves. One half was assigned to control subgroup 2, which was bonded with the single-step self-etching adhesive according to the manufacturer's instructions; the other half was assigned to experimental subgroup 2 in which three layers of adhesive were applied with light curing each successive layer. Microtensile bond strength was immediately tested after specimen preparation.


RESULTS
When the adhesive was applied three times before light curing, the bond strength of the experimental subgroup 1 (n=33, 57.49 +/-11.61 MPa) was higher than that of the control subgroup 1 (n=31, 49.71 +/-11.43 MPa, P<0.05). When using the technique of applying multiple layers of adhesive with light curing each successive layer, no difference of immediate bond strength was observed between the control subgroup 2 and the experimental subgroup 2 (P>0.05).


CONCLUSIONS
strength to primary dentin when using the technique of light-curing after applying three layers of adhesive.
Department of Stomatology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
Lin
L
Ma
Jian-feng
JF
Zhou
Jian-guo
JG
Tan
Quan
Q
Jing
Ji-zhi
JZ
Zhao
Kuo
K
Wan
D000269:Adhesives / Q000737:chemistry*; D001840:Dental Bonding; D003799:Dental Stress Analysis; D003804:Dentin / Q000737:chemistry*; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D006801:Humans; D066298:In Vitro Techniques; D008689:Methacrylates / Q000737:chemistry*; D013718:Tensile Strength
D000269:Adhesives; C103506:Bis-GMA, BPDM, HEMA dental-bonding resin; D017220:Dentin-Bonding Agents; D008689:Methacrylates