Development of a tetrafluoride varnish and evaluation of its chemical stability and anticaries activi

Author(s)

Carolina Bezerra Cavalcanti Nobrega

• Document type: Doctoral Thesis
• Press: Piracicaba, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Odontologia de Piracicaba
• Defense date: 2008-02-18

Examining board members

Pedro Luiz Rosalen; Fred Yukio Fujiwara; Raul Cesar Evangelista; Cinthia Pereira Machado Tabchoury; Marcelo Giannini

• Advisor: Jaime Aparecido Cury; Pedro Luiz Rosalen

Abstract

Fluorine has been used as the main alternative to control dental caries. A large number of chemical compounds are available for that purpose as titanium tetrafluoride (TiF4); however, TiF4 use has been limited due to its instability in aqueous solutions. In this way, the aim of this study was to develop a titanium tetrafluoride varnish (2.26% fluorine) and evaluate its in vitro chemical stability and anti-caries activity in rats. To evaluate the varnish chemical properties 19F nuclear magnetic resonance spectroscopy C9F-NMR) was used to identify and quantify titanium sub-products in fresh and aged varnishes. Additionally, the reactivity of fresh and aged varnishes was evaluated by quantifying fluoride, loosely (calcium fluoride) and firmly (fluorapatite) formed on dental enamel. To evaluate the anti-caries potential of the titanium tetrafluoride varnish, a caries animal model was used. Wistar SPF rats were randomly assigned to 4 groups (n=12) receiving 'on molars application of aged TiF4 varnish, Duraphat@ varnish (positive control- 2.26% fluorine), non fluoride varnísh (negative control) or no treatment and then submitted to a cariogenic challenge for 4 weeks. The varnish anti-caries effect was evaluated by incidence and severity of dental caries and oral biofilm composition. After the experimental períod, oral tissues of the rats were removed to analyze the local toxic effect of the varnish. Six titanium sub-products of the varnlsh were identified through NMR analysis and kept stable over the aging period. Deposition of fluorapatite on enamel ""as not changed during aging period (p>O.05); however, a reduction in calciumfluoride formation was verified (pO.05). No oral tissue alterations were verified by toxicological analyses. This new'TiF4 formulation might be considered a promising anti-caries agent (AU)