title: Relationship between toothpastes properties and patient-reported discomfort: crossover study.
abstract: OBJECTIVE
  This study aims to correlate patient-reported reactions with in vitro analyses of the pH, abrasive quality, and cytotoxicity of four toothpastes.
  
  
  METHODS
  One hundred twenty-one patients received non-identified samples of toothpaste to be used for 6 days and answered a questionnaire about their sensations. In vitro analysis: the pH of toothpastes was measured with a pH meter. The abrasivity of toothpastes was evaluated against composite resin specimens (n = 10). A toothbrushing machine was used to simulate wear, which was indirectly measured by mass loss using a scale. Cell culture media conditioned with toothpaste were used to assess the cytotoxicity. Confluent cells were kept in contact with the conditioned media or control for 24 h. The cell viability was measured using the 3-(bromide, 4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium (MTT)-reduction assay. The obtained data on the pH, weight loss, and cell viability were compared by ANOVA/Tukey's tests (p < 0.05).
  
  
  RESULTS
  With the exception of the bleaching effect paste, the Oral B® paste produced the highest frequencies of irritation reports, tooth sensitivity, taste discomfort, and texture discomfort in the clinical study; patients also reported rougher teeth, soft tissue peeling, dry mouth, thrush, tingling, and taste changes in response to this paste. The in vitro analysis demonstrated that Oral B® had the lowest pH, the highest abrasivity, and produced the lowest cell viability (p < 0.01).
  
  
  CONCLUSIONS
  Results suggest that low pH toothpastes that are highly abrasive and cytotoxic may cause undesirable reactions in patients.
  
  
  CONCLUSIONS
  Toothpaste's properties should be well known for indication to patient therefore minimizing discomfort reports.
authors.affiliation: Master Degree Program, School of Dentistry, Ibirapuera University, Chácara Flora, São Paulo, Brazil.
authors.forename: Mariana
authors.initials: M
authors.lastname: Bruno
authors.affiliation: School of Dentistry, University of São Paulo, São Paulo, Brazil.
authors.forename: Fernando
authors.initials: F
authors.lastname: Taddeo
authors.affiliation: School of Dentistry, University of São Paulo, São Paulo, Brazil.
authors.forename: Igor Studart
authors.initials: IS
authors.lastname: Medeiros
authors.affiliation: Master Degree Program, School of Dentistry, Santo Amaro University, São Paulo, Brazil.
authors.forename: Letícia Cristina Cidreira
authors.initials: LC
authors.lastname: Boaro
authors.affiliation: Master Degree Program, School of Dentistry, Ibirapuera University, Chácara Flora, São Paulo, Brazil.
authors.forename: Maria Stella N A
authors.initials: MS
authors.lastname: Moreira
authors.affiliation: School of Dentistry, University of São Paulo, São Paulo, Brazil.
authors.forename: Márcia Martins
authors.initials: MM
authors.lastname: Marques
authors.affiliation: Master Degree Program, School of Dentistry, Ibirapuera University, Chácara Flora, São Paulo, Brazil. fecalheiros@gmail.com.
authors.forename: Fernanda Calabró
authors.initials: FC
authors.lastname: Calheiros
mesh_terms: D000328:Adult; D002470:Cell Survival; D002478:Cells, Cultured; D003188:Composite Resins; D018592:Cross-Over Studies; D005260:Female; D005347:Fibroblasts / Q000187:drug effects; D005881:Gingiva / Q000166:cytology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008422:Materials Testing; D008875:Middle Aged; D011795:Surveys and Questionnaires; D014072:Tooth Abrasion / Q000209:etiology*; D014100:Toothpastes / Q000009:adverse effects* / Q000737:chemistry
chemical_list: D003188:Composite Resins; D014100:Toothpastes
keywords: Abrasivity; Crossover study; Cytotoxicity; Discomfort; Toothpaste