title: Protective effect of calcium nanophosphate and CPP-ACP agents on enamel erosion.
abstract: The aim of this study was to assess the effect of different remineralizing agents on enamel microhardness (KHN) and surface topography after an erosive challenge. Forty-eight human enamel specimens (4 × 4 mm) were randomly assigned to 4 groups: control (no treatment), fluoride varnish, calcium nanophosphate paste and casein phosphopeptide-amorphous calcium phosphate paste (CPP-ACP). Both pastes were applied for 5 minutes, and fluoride varnish, for 24 h. Four daily erosive cycles of 5 minutes of immersion in a cola drink and 2 h in artificial saliva were conducted for 5 days. KHN readings were performed at baseline and after 5 days. The percentage of enamel hardness change (%KHN) was obtained after erosion. The surface topography was evaluated by atomic force microscopy (AFM). The data were tested using ANOVA, Tukey's and paired-T tests (p < 0.05). After an erosive challenge, there was no statistically significant difference between the control (96.8 ± 11.4 KHN / 72.4 ± 3.0%KHN) and the varnish (91.7 ± 14.1 KHN / 73.4 ± 5.5%KHN) groups. The nanophosphate group showed lower enamel hardness loss (187.2 ± 27.9 / 49.0 ± 7.9%KHN), compared with the CPP-ACP group (141.8 ± 16.5 / 60.6 ± 4.0%KHN), and both were statistically different from the varnish and the control groups. AFM images showed a rough surface for the control and the varnish groups, a non-homogeneous layer with globular irregularities for CPP-ACP, and a thick homogeneous layer for the nanophosphate group. None of the agents provided protection against the development of erosion; however, nanophosphate paste was able to reduce enamel surface softening after the erosive challenge.
authors.affiliation: Department of Biological Science, Division of Dentistry, Universidade Federal de Campina Grande, PatosPB, Brazil.
authors.forename: Fabíola Galbiatti de
authors.initials: FG
authors.lastname: Carvalho
authors.affiliation: Department of Operative Dentistry, Centro de Ciências da Saúde, Universidade Federal da Paraíba, João PessoaPB, Brazil.
authors.forename: Veruska Lima Moura
authors.initials: VL
authors.lastname: Brasil
authors.affiliation: Department of Operative Dentistry, Centro de Ciências da Saúde, Universidade Federal da Paraíba, João PessoaPB, Brazil.
authors.forename: Tiago João da
authors.initials: TJ
authors.lastname: Silva Filho
authors.affiliation: Department of Operative Dentistry, Centro de Ciências da Saúde, Universidade Federal da Paraíba, João PessoaPB, Brazil.
authors.forename: Hugo Lemes
authors.initials: HL
authors.lastname: Carlo
authors.affiliation: Department of Biological Science, Division of Dentistry, Universidade Federal de Campina Grande, PatosPB, Brazil.
authors.forename: Rogério Lacerda dos
authors.initials: RL
authors.lastname: Santos
authors.affiliation: Department of Mechanical Technology, Laboratório de Solidificação Rápida, Universidade Federal da Paraíba, João PessoaPB, Brazil.
authors.forename: Bruno Alessandro Silva Guedes de
authors.initials: BA
authors.lastname: Lima
mesh_terms: D000704:Analysis of Variance; D002130:Calcium Phosphates / Q000627:therapeutic use*; D002253:Carbonated Beverages; D002364:Caseins / Q000627:therapeutic use*; D003743:Dental Enamel / Q000737:chemistry / Q000187:drug effects*; D006245:Hardness Tests; D006801:Humans; D018625:Microscopy, Atomic Force; D053758:Nanoparticles; D011897:Random Allocation; D015203:Reproducibility of Results; D012464:Saliva, Artificial / Q000737:chemistry; D013499:Surface Properties / Q000187:drug effects; D013997:Time Factors; D014077:Tooth Erosion / Q000517:prevention & control*; D014089:Tooth Remineralization / Q000379:methods*
chemical_list: D002130:Calcium Phosphates; D002364:Caseins; D012464:Saliva, Artificial; C447032:casein phosphopeptide-amorphous calcium phosphate nanocomplex