title: In vitro evaluation of adhesion/proliferation of human gingival fibroblasts on demineralized root surfaces by toluidine blue O in antimicrobial photodynamic therapy.
abstract: BACKGROUND
  Antimicrobial photodynamic therapy (aPDT) in Dentistry has important effects as bacterial destruction in areas with periodontal disease. Some dyes applied in aPDT could present low pH and, consequently, result in tooth demineralization. This study evaluated demineralization produced by aPDT with toluidine blue O (TBO) at low pH and analyzed adhesion/proliferation of human gingival fibroblasts (HGF).
  
  
  METHODS
  In the 1st phase, bovine enamel and root dentin fragments received 2 treatments: PDT4 group (TBO-100 μg/ml-pH 4-60s) plus laser (660 nm, 45 J/cm(2), 1.08 J, 30 mW, 30 s, spot 0.024 cm(2), 1.25 W/cm(2), sweeping, non-contact) and CA group (citric acid plus tetracycline-pH 1-180 s). Surface hardness loss and tooth wear were statistically analyzed (Student's t test, ANOVA/Tukey, p<0.05). In the 2nd phase, human dentin fragments were divided in C (control group-scaling and root planing), PDT4 and CA. HGF (10(4), 5th passage) were cultured on these fragments for 24, 48 and 72 h and counted in scanning electron microscopy photographs. Number of HGF was analyzed using repeated-measures ANOVA and Tukey (p<0.05).
  
  
  RESULTS
  Percentage of surface hardness loss was similar in dentin for PDT4 (71.5%) and CA (76.1%) (p>0.05) and higher in enamel for CA (68.0%) compared to PDT4 (34.1%) (p<0.05). In respect to wear, no difference was found between PDT4 (dentin: 12.58 μm, enamel: 12.19 μm respectively) and CA (dentin: 11.74 μm and enamel: 11.03 μm) (p>0.05). Number of HGF was higher after 72 h in CA group (2.66, p<0.05) compared to PDT4 (2.2) and C (1.33).
  
  
  CONCLUSIONS
  PDT4 is not as aggressive as CA for enamel. However, dentin demineralized promoted by PDT4 does not stimulate HGF adhesion and proliferation as CA.
authors.affiliation: Discipline of Periodontics, Bauru School of Dentistry, Brazil. Electronic address: cdamante@usp.br.
authors.forename: Carla Andreotti
authors.initials: CA
authors.lastname: Damante
authors.affiliation: Discipline of Periodontics, Bauru School of Dentistry, Brazil. Electronic address: paula.ducati@usp.br.
authors.forename: Paula
authors.initials: P
authors.lastname: Ducati
authors.affiliation: Discipline of Periodontics, Bauru School of Dentistry, Brazil. Electronic address: rafael2.ferreira@usp.br.
authors.forename: Rafael
authors.initials: R
authors.lastname: Ferreira
authors.affiliation: Discipline of Periodontics, Bauru School of Dentistry, Brazil. Electronic address: s.salmeron@usp.br.
authors.forename: Samira
authors.initials: S
authors.lastname: Salmeron
authors.affiliation: Discipline of Periodontics, Bauru School of Dentistry, Brazil. Electronic address: mariana@fob.usp.br.
authors.forename: Mariana Schutzer Ragghianti
authors.initials: MSR
authors.lastname: Zangrando
authors.affiliation: Discipline of Periodontics, Bauru School of Dentistry, Brazil. Electronic address: malurezende@usp.br.
authors.forename: Maria Lúcia Rubo
authors.initials: MLR
authors.lastname: de Rezende
authors.affiliation: Discipline of Periodontics, Bauru School of Dentistry, Brazil. Electronic address: acpsantana@usp.br.
authors.forename: Adriana Campos Passanezi
authors.initials: ACP
authors.lastname: Sant'Ana
authors.affiliation: Discipline of Periodontics, Bauru School of Dentistry, Brazil. Electronic address: slagregh@fob.usp.br.
authors.forename: Sebastião Luiz Aguiar
authors.initials: SLA
authors.lastname: Greghi
authors.affiliation: Discipline of Biochemistry, Bauru School of Dentistry, Brazil. Electronic address: acm@usp.br.
authors.forename: Ana Carolina
authors.initials: AC
authors.lastname: Magalhães
mesh_terms: D000818:Animals; D001424:Bacterial Infections / Q000188:drug therapy / Q000473:pathology; D018488:Bone Demineralization, Pathologic / Q000139:chemically induced* / Q000473:pathology*; D002417:Cattle; D002448:Cell Adhesion / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D003648:Decalcification Technique; D003743:Dental Enamel / Q000187:drug effects* / Q000473:pathology; D005347:Fibroblasts / Q000187:drug effects* / Q000473:pathology; D005881:Gingiva / Q000187:drug effects / Q000473:pathology; D005891:Gingivitis / Q000188:drug therapy / Q000473:pathology; D066298:In Vitro Techniques; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000008:administration & dosage / Q000009:adverse effects; D014048:Tolonium Chloride / Q000008:administration & dosage / Q000009:adverse effects*; D014092:Tooth Root / Q000187:drug effects* / Q000473:pathology; D016896:Treatment Outcome
chemical_list: D017319:Photosensitizing Agents; D014048:Tolonium Chloride
keywords: Phenothiazinium dyes; Photochemotherapy; Tooth demineralization