title: Poly (amido amine) and nano-calcium phosphate bonding agent to remineralize tooth dentin in cyclic artificial saliva/lactic acid.
abstract: The objectives of this study were to develop a novel method to remineralize dentin lesions, and investigate the remineralization effects of poly (amido amine) (PAMAM) dendrimer plus a bonding agent with nanoparticles of amorphous calcium phosphate (NACP) in a cyclic artificial saliva/lactic acid environment for the first time. Dentin lesions were produced via phosphoric acid. Four groups were tested: (1) dentin control, (2) dentin with PAMAM, (3) dentin with NACP bonding agent, and (4) dentin with PAMAM plus NACP bonding agent. Specimens were treated with cyclic artificial saliva/lactic acid. The remineralized dentin was examined using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), hardness and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). NACP bonding agent yielded a dentin shear bond strength similar to commercial controls (Prime & Bond NT, Dentsply; Scotchbond Multi-purpose, 3M) (p>0.1). Increasing NACP in bonding agent from 0 to 40% did not affect bond strength. NACP bonding agent neutralized the acid and released Ca ions with concentrations of 4 to 20mmol/L, and P ions of 2 to 9mmol/L. PAMAM or NACP bonding agent alone achieved slight remineralization. The PAMAM+NACP group achieved the greatest dentin remineralization p<0.05). At 20days, PAMAM+NACP increased the hardness of pre-demineralized dentin to reach the normal dentin hardness (p>0.1). In conclusion, superior remineralization of PAMAM+NACP bonding agent was demonstrated for the first time. PAMAM+NACP bonding agent induced dentin remineralization under acid challenge, when conventional remineralization methods such as PAMAM alone did not work well. The novel PAMAM+NACP bonding agent method is promising to improve the longevity of resin-dentin bonds, inhibit caries, and protect teeth.
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China; Department of Endodontics, Periodontics and Prosthodontics, University of Maryland School of Dentistry, Baltimore, MD 21201, USA.
authors.forename: Kunneng
authors.initials: K
authors.lastname: Liang
authors.affiliation: Department of Endodontics, Periodontics and Prosthodontics, University of Maryland School of Dentistry, Baltimore, MD 21201, USA.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Weir
authors.affiliation: Department of Endodontics, Periodontics and Prosthodontics, University of Maryland School of Dentistry, Baltimore, MD 21201, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Reynolds
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China.
authors.forename: Xuedong
authors.initials: X
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China. Electronic address: jiyaoliscu@163.com.
authors.forename: Jiyao
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Endodontics, Periodontics and Prosthodontics, University of Maryland School of Dentistry, Baltimore, MD 21201, USA; Center for Stem Cell Biology & Regenerative Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Mechanical Engineering, University of Maryland Baltimore County, Baltimore County, MD 21250, USA. Electronic address: hxu@umaryland.edu.
authors.forename: Hockin H K
authors.initials: HHK
authors.lastname: Xu
mesh_terms: D002130:Calcium Phosphates / Q000737:chemistry*; D003804:Dentin / Q000737:chemistry*; D006244:Hardness; D019344:Lactic Acid / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry*; D010756:Phosphoric Acids / Q000737:chemistry; D011073:Polyamines / Q000737:chemistry*; D012464:Saliva, Artificial / Q000737:chemistry*; D033081:Shear Strength; D013052:Spectrometry, X-Ray Emission; D017550:Spectroscopy, Fourier Transform Infrared; D014783:Viscosity
chemical_list: D002130:Calcium Phosphates; D010756:Phosphoric Acids; C531249:Poly(amidoamine); D011073:Polyamines; D012464:Saliva, Artificial; C519480:amorphous calcium phosphate; D019344:Lactic Acid; C030242:phosphoric acid
keywords: Acid challenge; Bonding agent; Calcium phosphate nanoparticles; Dentin; Poly (amido amine) dendrimer; Remineralization