Effectiveness and stability of silane coupling agent incorporated in 'universal' adhesives

Kumiko Yoshihara; Noriyuki Nagaoka; Akinari Sonoda; Yukinori Maruo; Yoji Makita; Takumi Okihara; Masao Irie; Yasuhiro Yoshida; Bart Van Meerbeek

doi:10.1016/j.dental.2016.07.002

Effectiveness and stability of silane coupling agent incorporated in 'universal' adhesives

Dent Mater. 2016 Oct;32(10):1218-1225. doi: 10.1016/j.dental.2016.07.002. Epub 2016 Jul 25.

Authors

Kumiko Yoshihara¹, Noriyuki Nagaoka², Akinari Sonoda³, Yukinori Maruo⁴, Yoji Makita⁵, Takumi Okihara⁶, Masao Irie⁷, Yasuhiro Yoshida⁸, Bart Van Meerbeek⁹

Affiliations

¹ Center for Innovative Clinical Medicine, Okayama University Hospital, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan. Electronic address: k-yoshi@md.okayama-u.ac.jp.
² Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Dental School, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan. Electronic address: nagaoka@okayama-u.ac.jp.
³ Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2217-14 Hayashi-cho, Takamatsu, Kagawa 761-0395, Japan. Electronic address: a.sonoda@aist.go.jp.
⁴ Department of Occlusion and Removable Prosthodontics, Okayama University Hospital, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan. Electronic address: ykmar@md.okayama-u.ac.jp.
⁵ Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2217-14 Hayashi-cho, Takamatsu, Kagawa 761-0395, Japan. Electronic address: y-makita@aist.go.jp.
⁶ Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-Naka, Kita-ku, Okayama 700-8530, Japan. Electronic address: okihara@cc.okayama-u.ac.jp.
⁷ Department of Biomaterials, Graduate School of Medicine, Dentistry and Phamaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan. Electronic address: mirie@md.okayama-u.ac.jp.
⁸ Department of Biomaterials and Bioengineering, Graduate School of Dental Medicine, Hokkaido University, Kita 13, Nishi 7, Kita-ku, Sapporo, Hokkaido, 060-8586, Japan. Electronic address: yasuhiro@den.hokudai.ac.jp.
⁹ KU Leuven (University of Leuven), Department of Oral Health Sciences, BIOMAT & University Hospitals Leuven, Dentistry, Kapucijnenvoer 7 blok a bus 7001, B-3000 Leuven, Belgium. Electronic address: bart.vanmeerbeek@med.kuleuven.be.

PMID: 27461880
DOI: 10.1016/j.dental.2016.07.002

Abstract

Objective: For bonding indirect restorations, some 'universal' adhesives incorporate a silane coupling agent to chemically bond to glass-rich ceramics so that a separate ceramic primer is claimed to be no longer needed. With this work, we investigated the effectiveness/stability of the silane coupling function of the silanecontaining experimentally prepared adhesives and Scotchbond Universal (3MESPE).

Methods and materials: Experimental adhesives consisted of Scotchbond Universal and the silane-free Clearfil S3 ND Quick (Kuraray Noritake) mixed with Clearfil Porcelain Bond Activator (Kuraray Noritake) and the two adhesives to which γ-methacryloxypropyltrimethoxysilane (γ-MPTS) was added. Shear bond strength was measured onto silica-glass plates; the adhesive formulations were analyzed using fourier transform infrared spectroscopy (FTIR) and 13C nuclear magnetic resonance (NMR). In addition, shear bond strength onto CAD-CAM composite blocks was measured without and after thermo-cycling ageing.

Results: A significantly higher bond strength was recorded when Clearfil Porcelain Bond Activator was freshly mixed with the adhesive. Likewise, the experimental adhesives, to which γ-MPTS was added, revealed a significantly higher bond strength, but only when the adhesive was applied immediately after mixing; delayed application resulted in a significantly lower bond strength. FTIR and (13)C NMR revealed hydrolysis and dehydration condensation to progress with the time after γ-MPTS was mixed with the two adhesives. After thermo-cycling, the bond strength onto CAD-CAM composite blocks remained stable only for the two adhesives with which Clearfil Porcelain Bond Activator was mixed.

Significance: Only the silane coupling effect of freshly prepared silanecontaining adhesives was effective. Clinically, the use of a separate silane primer or silane freshly mixed with the adhesive remains recommended to bond glass-rich ceramics.

Keywords: Bond strength; Coupling agent; FTIR; NMR; Silane; Universal adhesive.

MeSH terms

Adhesives
Dental Bonding*
Dental Porcelain
Materials Testing
Methacrylates*
Resin Cements*
Silanes*

Substances

Adhesives
Methacrylates
Resin Cements
Silanes
Dental Porcelain
methacryloxypropyltrimethoxysilane