Bonding to root caries by a self-etching adhesive system containing MDPB.
OBJECTIVE
To evaluate the bonding of an experimental antibacterial fluoride-releasing adhesive system (ABF) to normal and carious dentin in human teeth with Class V root caries.


METHODS
Mesiodistal sectioning removed the buccal enamel, superficial dentin and much of the carious dentin in 21 extracted human bicuspids with root surface caries. The surfaces of normal coronal and root dentin, and caries-affected and caries-infected dentin were ground with wet 600-grit SiC paper to create a standardized smear layer. Tooth surfaces were treated with the ABF according to manufacturer's instructions, and then covered with excess resin composite. After immersion in 37 degrees C water for 24 hours, the restored teeth were horizontally sectioned into serial slabs that were trimmed into hourglass shapes to isolate the bonded area to the test substrates, and then their bond strengths were measured by the microtensile bond test, and the interfaces examined by SEM and TEM. The bond strengths were statistically compared with ANOVA and Fisher's PLSD (P < 0.05).


RESULTS
The bond strengths of ABF to caries-affected and caries-infected dentin were significantly lower than those to normal coronal and root dentin. SEM micrographs revealed that the hybrid layers in caries-affected and caries-infected dentin were more porous compared to the hybrid layer in normal coronal and root dentin. TEM micrographs showed that bacteria that had invaded the dentin were embedded in this adhesive monomer in caries-infected dentin.


CONCLUSIONS
Although the bond strength of ABF adhesive system to root carious dentin is lower than that of normal dentin, the antibacterial and fluoride-releasing properties of ABF may contribute to prevent caries progression and inhibit secondary caries.
Doi
Junichi
J
Department of Operative Dentistry, Study of Biofunctional Recovery and Reconstruction, Okayama University Graduate School of Medicine and Dentistry, 2-5-1 Shikata-cho, Okayama 700-8525, Japan. j_doi@md.okayama-u.ac.jp
Itota
Toshiyuki
T
Yoshiyama
Masahiro
M
Tay
Franklin R
FR
Pashley
David H
DH
D000134:Acid Etching, Dental; D000704:Analysis of Variance; D000891:Anti-Infective Agents, Local; D001641:Bicuspid; D002327:Cariostatic Agents; D003793:Dental Restoration, Permanent / Q000379:methods*; D003799:Dental Stress Analysis; D017220:Dentin-Bonding Agents / Q000737:chemistry; D005459:Fluorides; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D011726:Pyridinium Compounds; D017213:Root Caries / Q000628:therapy*; D013499:Surface Properties; D013718:Tensile Strength
C481356:ABF system; D000891:Anti-Infective Agents, Local; D002327:Cariostatic Agents; D017220:Dentin-Bonding Agents; D008689:Methacrylates; D011726:Pyridinium Compounds; C089392:methacryloyloxydodecylpyridinium bromide; D005459:Fluorides