title: Evaluation of the force applied by the tongue and lip on the maxillary central incisor tooth.
abstract: OBJECTIVE
  To describe the development and testing of a system that measures forces exerted by the tongue and upper lip on a tooth during rest and during swallowing.
  
  
  METHODS
  Twenty-eight subjects, aged 19-31 years (mean: 23.2 years) were submitted to measurement of forces exerted by the upper lip and tongue on the maxillary right central incisor tooth. Flexiforce resistive sensors were fixed on the labial and lingual surfaces of the tooth. They were connected to an amplifier circuit and a data acquisition board for processing and transmitting information to a computer.
  
  
  RESULTS
  At rest, the tongue force on the tooth was 0.00±0.00 N and the lip force on tooth was 0.02±0.02 N. The difference between them was significant. During swallowing, the values were 0.31±0.38 N and 0.15±0.14 N, for the tongue and lip, respectively. This difference was not significant.
  
  
  CONCLUSIONS
  At rest, the lip exerts a larger force than the tongue on the maxillary right central incisor tooth. During swallowing, there was no difference between lip and tongue force on the tooth.
authors.affiliation: Prefeitura Municipal de Nova Lima, Nova Lima, MG, Brazil.
authors.forename: Amanda Freitas
authors.initials: AF
authors.lastname: Valentim
authors.affiliation: Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Renata Maria Moreira Moraes
authors.initials: RM
authors.lastname: Furlan
authors.affiliation: Instituto Metodista Izabela Hendrix, Belo Horizonte, MG, Brazil.
authors.forename: Tatiana Vargas de Castro
authors.initials: TV
authors.lastname: Perilo
authors.affiliation: Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Monalise Costa Batista
authors.initials: MC
authors.lastname: Berbert
authors.affiliation: Department of Speech Language Pathology and Audiology, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Andréa Rodrigues
authors.initials: AR
authors.lastname: Motta
authors.affiliation: Department of structural engineering, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Estevam Barbosa
authors.initials: EB
authors.lastname: de Las Casas
mesh_terms: D000328:Adult; D003679:Deglutition / Q000502:physiology*; D003799:Dental Stress Analysis; D005260:Female; D006801:Humans; D007180:Incisor / Q000502:physiology*; D008046:Lip / Q000502:physiology*; D008297:Male; D053580:Muscle Strength; D014059:Tongue / Q000502:physiology*; D055815:Young Adult