Effect of salivary flow on masticatory efficiency and interocclusal distance during speech

Author(s)

Simone Guimarães Farias Gomes

• Document type: Master's Dissertation
• Press: Piracicaba, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Odontologia de Piracicaba
• Defense date: 2008-11-04

Examining board members

Renata Cunha Matheus Rodrigues Garcia; Raphael Freitas de Souza; Maria Beatriz Duarte Gavião

• Advisor: Renata Cunha Matheus Rodrigues Garcia

Abstract

Saliva is a complex fluid which performs various functions, as assisting important activities of the stomatognathic system such as mastication and speech articulation. The lack or reduction of salivary flow affects its functions and causes discomfort. This study objectively evaluated the effect of salivary flow rate on the masticatory efficiency and interocclusal distance during speech. Sixty healthy fully dentate subjects were divided into 3 groups: (1) control, composed by subjects with normal salivary flow rate; (2) hyposalivation, composed by subjects with reduced salivary flow rate; (3) hypersalivation, composed by subjects with increased salivary flow rate. To establish group 2, twenty subjects who used systemic oral isotretinoin were selected. This drug is indicated for dermatologic treatment and its most common side effect is dry mouth. Group 3 hypersalivation condition was conducted by 6% citric acid dripping on tongue lateral borders. The salivary flow was measured immediately before the tests to confirm the salivary condition of the subjects. Masticatory efficiency was evaluated by means of the percentage of an artificial material (Optosil®) which can pass through the 10-mesh sieve after 20 chewing strokes, using a sieving method. The interocclusal distance during the pronunciation of all the Brazilian Portuguese language phonemes was measured using an electromagnetic jaw-tracking method, Recorded data were analyzed by ANOVA (P=0,05). The comparison of masticatory efficiency and interocclusal distance during speech among subjects with different salivary conditions revealed no significant differences. Within the conditions this study, it is possible to conclude that subjects with reduced or induced salivary flow rate presented neither masticatory efficiency nor interocclusal distance during speech alterations when compared with subjects with normal salivary flow rate. Key Words: Saliva, mastication, communication (AU)

• FAPESP's process: 05/03383-1 - Effect of salivary flow on masticatory efficiency and interocclusal distance during speech
• Grantee: Simone Guimarães Farias Gomes
• Support Opportunities: Scholarships in Brazil - Master