Effects of high-speed cutting on dentin permeability and bonding.
The effects of high-speed cutting by use of a diamond bur with or without water coolant or sanding by 80-grit SiC paper on dentin permeability, before and after surface treatment, and dentin bonding of adhesive resins were compared. Three different bonding systems were used: Scotchbond DC, which requires no removal of smear layers, and two others, Clearfil Photobond and Superbond C&B, both of which remove smear layers (phosphoric acid gel or 10% citric acid containing 3% ferric chloride, respectively). Creation of smear layers by bur cutting or sanding reduced dentin permeability to levels that were only 1-3% of the maximum permeability values. Scotchbond DC gave low but consistent bond strengths (3.7-6.1 MPa) to dentin covered with smear layers. Clearfil PHotobond also produced consistent bond strengths (8.6-9.4 MPa). The increase in the permeability of dentin after phosphoric acid treatment was higher when the SiC paper was used (146%) than when the high-speed bur was used (87-90%). The smear layer and smear plugs produced by the diamond bur were more resistant to 10-3 treatment than were the SiC-created smear layers. The bond strengths of Superbond showed the highest bond strengths to the conditioned dentin when the high-speed cutting was used with water coolant (16.3 MPa), compared with the other two groups (12.2-12.5 MPa).
Tagami
J
J
Department of Operative Dentistry, Tokyo Medical and Dental University.
Tao
L
L
Pashley
D H
DH
Hosoda
H
H
Sano
H
H
D000704:Analysis of Variance; D001896:Boron Compounds; D003188:Composite Resins; D001840:Dental Bonding / Q000379:methods*; D003738:Dental Cements; D003755:Dental High-Speed Technique; D003806:Dentin Permeability; D006801:Humans; D008689:Methacrylates; D008768:Methylmethacrylates; D008855:Microscopy, Electron, Scanning; D019279:Resin Cements; D016369:Smear Layer; D013718:Tensile Strength; D014867:Water
D001896:Boron Compounds; D003188:Composite Resins; D003738:Dental Cements; D008689:Methacrylates; D008768:Methylmethacrylates; D019279:Resin Cements; D014867:Water; C074046:Photo Clearfil A; C074318:Scotchbond Dual Cure; C074669:Clearfil Photo Bond; C049495:Super-bond