Effects of CPP-ACP paste on the shear bond strength of orthodontic brackets.
OBJECTIVE
To evaluate the effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste on shear bond strength and debonding failure modes of orthodontic brackets.


METHODS
Freshly extracted premolars were randomly divided into four groups (n =18) as follows: in groups 1 and 3, the enamel was treated with a solution of CPP-ACP dissolved in artificial saliva; groups 2 and 4 served as controls, and the enamel was treated with artificial saliva. After conventional acid etching, in groups 1 and 2, brackets were bonded using a light-cured bonding system (Blugloo); while in groups 3 and 4, brackets were bonded using a conventional bonding system (Unite Bonding Adhesive). Bonded specimens were subjected to thermal cycling for 1000 cycles before debonding procedures. After debonding, teeth and brackets were examined under a stereomicroscope at 10x magnification to determine whether any adhesive remained, in accordance with the adhesive remnant index. The acid-etched enamel surfaces were also observed using scanning electron microscopy after treatment with and without CPP-ACP paste.


RESULTS
The shear bond strengths of group 1 were significantly higher than those seen in group 2 (P < .01). There was no significant difference in the shear bond strengths of groups 3 and 4 (P > .05). Scanning electron microscopic observation showed that the pretreated enamel surface was rougher than that of the control surface after acid etching.


CONCLUSIONS
The use of CPP-ACP can be considered as an alternative prophylactic application in orthodontic practice since it did not compromise bracket bond strength.
Xiaojun
Ding
D
Department of Stomatology, Zhongshan Hospital, Shanghai Medical School, Fudan University, Ninth People's Hospital, School of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology and Shanghai Research Institute of Stomatology, Shanghai, China.
Jing
Lu
L
Xuehua
Guo
G
Hong
Ruan
R
Youcheng
Yu
Y
Zhangyu
Gu
G
Sun
Jian
J
D000180:Acrylic Resins; D001641:Bicuspid; D002327:Cariostatic Agents / Q000494:pharmacology*; D002364:Caseins / Q000494:pharmacology*; D001840:Dental Bonding; D003743:Dental Enamel / Q000187:drug effects; D003799:Dental Stress Analysis; D006801:Humans; D016910:Orthodontic Brackets; D019279:Resin Cements; D033081:Shear Strength; D013499:Surface Properties / Q000187:drug effects
D000180:Acrylic Resins; C522883:Blugloo; D002327:Cariostatic Agents; D002364:Caseins; D019279:Resin Cements; C045638:Unite dental cement; C447032:casein phosphopeptide-amorphous calcium phosphate nanocomplex