Chlorhexidine-modified nanotubes and their effects on the polymerization and bonding performance of a dental adhesive

Sara Kalagi; Sabrina A Feitosa; Eliseu A Münchow; Victor M Martins; Ashley E Karczewski; N Blaine Cook; Kim Diefenderfer; George J Eckert; Saulo Geraldeli; Marco C Bottino

doi:10.1016/j.dental.2020.03.007

Chlorhexidine-modified nanotubes and their effects on the polymerization and bonding performance of a dental adhesive

Dent Mater. 2020 May;36(5):687-697. doi: 10.1016/j.dental.2020.03.007. Epub 2020 Mar 30.

Authors

Affiliations

¹ Department of Cariology, Operative Dentistry & Dental Public Health, Indiana University School of Dentistry (IUSD), Indianapolis, IN, USA; Department of Restorative Dental Sciences, College of Dentistry, King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia.
² Department of Biomedical and Applied Sciences, Division of Dental Biomaterials, IUSD, Indianapolis, IN, USA.
³ Department of Conservative Dentistry, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS 90035-003, Brazil.
⁴ Department of Cariology, Operative Dentistry & Dental Public Health, Indiana University School of Dentistry (IUSD), Indianapolis, IN, USA.
⁵ Department of Biostatistics, Indiana University School of Medicine, Indianapolis, IN, USA.
⁶ Department of General Dentistry, School of Dental Medicine, East Carolina University, Greenville, NC, USA.
⁷ Department of Cariology, Restorative Sciences and Endodontics, University of Michigan School of Dentistry, Ann Arbor, MI, USA. Electronic address: mbottino@umich.edu.

Abstract

Objectives: The purpose of this study was to synthesize chlorhexidine (CHX)-encapsulated aluminosilicate clay nanotubes (Halloysite®, HNTs) and to incorporate them into the primer/adhesive components of an etch-and-rinse adhesive system (SBMP; Scotchbond Multipurpose, 3M ESPE) and to test their effects on degree of conversion, viscosity, immediate and long-term bonding to dentin.

Methods: CHX-modified HNTs were synthesized using 10% or 20% CHX solutions. The primer and the adhesive components of SBMP were incorporated with 15wt.% of the CHX-encapsulated HNTs. Degree of conversion (DC) and viscosity analyses were performed to characterize the modified primers/adhesives. For bond strength testing, acid-etched dentin was treated with one of the following: SBMP (control); 0.2%CHX solution before SBMP; CHX-modified primers+SBMP adhesive; SBMP primer+CHX-modified adhesives; and SBMP primer+CHX-free HNT-modified adhesive. The microtensile bond strength test was performed after immediate (24h) and long-term (6 months) of water storage. Data were analyzed using ANOVA and Tukey (α=5%) and the Weibull analysis.

Results: DC was greater for the CHX-free HNT-modified adhesive, whereas the other experimental adhesives showed similar DC as compared with the control. Primers were less viscous than the adhesives, without significant differences within the respective materials. At 24h, all groups showed similar bonding performance and structural reliability; whereas at the 6-month period, groups treated with the 0.2%CHX solution prior bonding or with the CHX-modified primers resulted in greater bond strength than the control and superior reliability.

Significance: The modification of a primer or adhesive with CHX-encapsulated HNTs was an advantageous approach that did not impair the polymerization, viscosity and bonding performance of the materials, showing a promising long-term effect on resin-dentin bonds.

Keywords: Adhesives; Aluminosilicate clay; Bonding; Dentin; Halloysite; Microtensile; Nanotube.

Publication types

Research Support, N.I.H., Extramural

MeSH terms

Chlorhexidine
Dental Bonding*
Dentin
Dentin-Bonding Agents
Materials Testing
Microscopy, Electron, Scanning
Nanotubes*
Polymerization
Reproducibility of Results
Resin Cements
Surface Properties
Tensile Strength

Substances

Dentin-Bonding Agents
Resin Cements
Chlorhexidine

Abstract

Publication types

MeSH terms

Substances

Grants and funding