Remineralising Dentine Caries Using Sodium Fluoride with Silver Nanoparticles: An In Vitro Study
Received 29 January 2020
Accepted for publication 23 March 2020
Published 23 April 2020 Volume 2020:15 Pages 2829—2839
Checked for plagiarism Yes
Review by Single anonymous peer review
Peer reviewer comments 2
Editor who approved publication: Prof. Dr. Anderson Oliveira Lobo
Irene Shuping Zhao,1,2 Iris Xiaoxue Yin,2 May Lei Mei,3 Edward Chin Man Lo,2 Jinyao Tang,4 Quanli Li,5 Lok Yan So,6 Chun Hung Chu2
1School of Dentistry, Shenzhen University Health Science Center, Shenzhen, People’s Republic of China; 2Faculty of Dentistry, The University of Hong Kong, Hong Kong, People’s Republic of China; 3Faculty of Dentistry, University of Otago, Dunedin, New Zealand; 4Department of Chemistry, The University of Hong Kong, Hong Kong, People’s Republic of China; 5School of Stomatology, Anhui Medical University, Hefei, People’s Republic of China; 6Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, People’s Republic of China
Correspondence: Chun Hung Chu
Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Hong Kong, People’s Republic of China
Objective: To investigate the remineralizing and staining effects of sodium fluoride (NaF) solution with polyethylene glycol-coated silver nanoparticles (PEG-AgNPs) on artificial dentine caries.
Materials and Methods: Demineralized human dentine blocks were allocated to three groups. The blocks in group 1 underwent a topical application of a 12% silver diamine fluoride (SDF, 14,150 ppm fluoride) solution. The blocks in group 2 received a topical application of a 2.5% NaF (11,310 ppm fluoride) with PEG-AgNPs (400 ppm silver). The blocks in group 3 received deionized water. All blocks were subjected to pH cycling for 8 days. The surface morphology and cross-sectional features were investigated using scanning electron microscopy (SEM). The color parameters, crystal characteristics, lesion depth, and collagen degradation of the blocks were assessed using digital spectrophotometry, X-ray diffraction (XRD), micro-computed tomography, and spectrophotometry with a hydroxyproline assay, respectively.
Results: The SEM showed that dentine collagen was exposed in group 3 but not in groups 1 and 2. The mean lesion depths in groups 1 to 3 were 118± 7 μm, 121± 14 μm, and 339± 20 μm, respectively (groups1,2< 3; p< 0.001). The data indicated that fluoridated PEG-AgNPs introduced no significant color effect on dentine, but SDF caused distinct discoloration. The XRD indicated that silver chloride was formed in group 1, and fluorapatite was detected in groups 1 and 2. The concentration of hydroxyproline liberated from collagen was significantly less in groups 1 and 2 than in group 3.
Conclusion: The use of NaF solution with PEG-AgNPs can remineralize artificial dentine caries and inhibit collagen degradation without causing significant tooth staining.
Keywords: silver, nanoparticles, fluoride, dentine, caries, remineralization