Technique-sensitivity of contemporary adhesives.
Besides micro-mechanical interlocking through hybrid-layer formation, self-etch adhesives may benefit from additional chemical interaction between the functional monomer and residual hydroxyapatite. One-step adhesives are commonly associated with lower bonding effectiveness, which must be attributed in part to the dissolution of hydrophilic and hydrophobic monomers in a relatively highly concentrated solvent. In this 'difficult' mixture, also water is essential as ionization medium to enable self-etching activity. Due to the high hydrophilicity, one-step self-etch adhesives have been reported to behave as semi-permeable membranes, allowing fluids to pass through and seriously jeopardizing bond durability. Recent research has also revealed that HEMA-free one-step adhesives are prone to phase-separation, which may also account for their lower bonding effectiveness. Employing an appropriate air-drying technique may, however, improve the bonding effectiveness of such phase-separating adhesives by getting rid of substantially more interfacial water than HEMA-containing adhesives, of which water might be more difficult to remove from.
Van Meerbeek
Bart
B
Leuven BIOMAT Research Cluster, Department of Conservative Dentistry, School of Dentistry, Oral Pathology and Maxillo-Facial Surgery, Catholic University of Leuven, Belgium. bart.vanmeerbeek@med.kuleuven.ac.be
Van Landuyt
Kirsten
K
De Munck
Jan
J
Hashimoto
Masanori
M
Peumans
Marleen
M
Lambrechts
Paul
P
Yoshida
Yasuhiro
Y
Inoue
Satoshi
S
Suzuki
Kazuomi
K
D000134:Acid Etching, Dental; D000269:Adhesives / Q000737:chemistry* / Q000145:classification; D001840:Dental Bonding / Q000379:methods*; D003745:Dental Enamel Permeability; D003806:Dentin Permeability; D017220:Dentin-Bonding Agents / Q000737:chemistry*; D005899:Glass Ionomer Cements / Q000737:chemistry*; D008689:Methacrylates / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry*; D014906:Wetting Agents / Q000737:chemistry
D000269:Adhesives; D017220:Dentin-Bonding Agents; D005899:Glass Ionomer Cements; D008689:Methacrylates; D019279:Resin Cements; D014906:Wetting Agents; C005044:hydroxyethyl methacrylate