title: Airpolishing effect on bovine enamel and the posterior remineralizing effect of saliva. An in vitro study.
abstract: OBJECTIVE
  The aim of the present study was to evaluate the alterations of surface microhardness and wear caused by the sodium bicarbonate jet on bovine enamel and the further remineralizing effect of artificial saliva.
  
  
  METHODS
  Fifteen enamel samples (4,0mm x 4,0mm) were used, which constituted the groups: no treatment (MI); treatment with sodium bicarbonate jet (MII and DI); treatment with sodium bicarbonate jet and immersion in saliva for one hour (MIII and DII), 24 hours (MIV and DIII) and 7 days (MV and DIV). Microhardness tests were carried out using a microdurometer in groups M and wear tests by a rugosimeter in groups D. The data were assessed by the one criterion variance analysis and Tukey test.
  
  
  RESULTS
  The mean value of microhardness, in KHN, in groups MI, MII, MIII, MIV and MV were 359,80; 335,46; 369,20; 377,73 and 341,86, respectively, whereas the mean values in microm, of wear for group DI, DII, DIII and DIV were 0,564; 0,519; 0,441 and 0,428, respectively.
  
  
  CONCLUSIONS
  The sodium bicarbonate jet caused a wear and a reduction in microhardness on the enamel surface; saliva promoted the recovery of initial condition surface microhardness and reduced the wear; the repairing effect of saliva on the surface microhardness alterations occurred within one hour of treatment, having no significant statistical difference from the effect obtained in 24 hours; the best saliva repairing effect on the wear occurred with treatment of 24 hours.
authors.affiliation: Department of Pediatric Dentistry, Bauru School of Dentistry, University of Sao Paulo. helenavono@hotmail.com
authors.forename: Helena Zaramella Vono
authors.initials: HZ
authors.lastname: Ribeiro
authors.forename: José Eduardo de Oliveira
authors.initials: JE
authors.lastname: Lima
authors.forename: Bernardo Gonzalez
authors.initials: BG
authors.lastname: Vono
authors.forename: Maria Aparcida de Andrade Moreira
authors.initials: MA
authors.lastname: Machado
authors.forename: Salete Moura Bonifácio
authors.initials: SM
authors.lastname: da Silva