title: Mineralising and antibacterial effects of modified calcium phosphate treatment on human root cementum.
abstract: BACKGROUND
  Aging population will lead to the increase of incidence of root caries globally. The clinical management of root caries is challenging due to the difficulty in moisture isolation. The root caries is caused by the release of organic acids from cariogenic bacteria which results in the dissolution of cementum and dentin of the root. The purpose of this study is to study the efficacy of modified saturated calcium phosphate solution (CaP) supplement with zinc (Zn(2+)) and/or fluoride (F(-)) in providing root cementum surfaces less susceptible to acid dissolution and bacterial colonization.
  
  
  METHODS
  Human root cementum sections from extracted premolars were treated with three modified calcium phosphate solutions (M/A-CaPs) respectively: (A) CaP-F/Zn, supplemented with F(-) and Zn(2+); (B) CaP-F, supplemented with F(-) only; (C) CaP-Zn, supplemented with Zn(2+) only. The surface characteristics of treated cementum sections were investigated using scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FT-IR). Following the acid attack and Streptococcus mutans challenge, M/A-CaPs treated cementum surfaces were analysed using inductive coupled plasma (ICP) and SEM respectively.
  
  
  RESULTS
  Compared with the control group, M/A-CaPs treated cementum presented significant improvements in resistance to acid dissolution and bacterial colonization. Among M/A-CaPs, the CaP-F/Zn treated cementum surfaces released the lowest amount of Ca(2+) ions (2.11 ± 0.51 ppm) upon acid challenge (n = 3, p < 0.01) and also presented the most significant inhibiting effect against the colonization of S. mutans (n = 180, p < 0.05).
  
  
  CONCLUSIONS
  Saturated calcium phosphate solution CaP supplemented with both F(-) and Zn(2+) could be applied as an effective coating material providing acid resistance and antibacterial property on cementum surfaces. The modified calcium phosphate-based solution could be a new treatment strategy to prevent the development of root caries and arrest the further progression of root caries.
authors.affiliation: Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University & Guangdong Provincial Key Laboratory of Stomatology, 56 Ling Yuan Xi Road, Guangzhou, 510055, China.|Department of Biomaterials & Biomimetics, New York University College of Dentistry, New York City, USA.
authors.forename: Haijing
authors.initials: H
authors.lastname: Gu
authors.affiliation: Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University & Guangdong Provincial Key Laboratory of Stomatology, 56 Ling Yuan Xi Road, Guangzhou, 510055, China. Lingjq@mail.sysu.edu.cn.
authors.forename: Junqi
authors.initials: J
authors.lastname: Ling
authors.affiliation: Faculty of Dentistry, University of Sydney, Sydney, NSW, Australia.|Institute of Dental Research, Westmead Centre for Oral Health, Westmead Millennium Institute, Westmead, 2153, NSW, Australia.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University & Guangdong Provincial Key Laboratory of Stomatology, 56 Ling Yuan Xi Road, Guangzhou, 510055, China.
authors.forename: Limin
authors.initials: L
authors.lastname: Liu
authors.affiliation: Guangdong Provincial Institute of Traditional Chinese Medicine, Guangzhou, China.
authors.forename: Ziming
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: Faculty of Dentistry, University of Sydney, Sydney, NSW, Australia. jinlong.gao@sydney.edu.au.|Institute of Dental Research, Westmead Centre for Oral Health, Westmead Millennium Institute, Westmead, 2153, NSW, Australia. jinlong.gao@sydney.edu.au.
authors.forename: Jin-Long
authors.initials: JL
authors.lastname: Gao
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002118:Calcium; D002130:Calcium Phosphates / Q000494:pharmacology*; D003739:Dental Cementum / Q000382:microbiology*; D006801:Humans; D017550:Spectroscopy, Fourier Transform Infrared; D014092:Tooth Root
chemical_list: D000900:Anti-Bacterial Agents; D002130:Calcium Phosphates; D002118:Calcium
keywords: Anti-microbial; Cementum; Modified calcium phosphate; Remineralisation; Root caries