Giovanna Dalpasquale1, Alberto Carlos Botazzo Delbem1, Juliano Pelim Pessan1, Gabriel Pereira Nunes1, Luiz Fernando Gorup2, Francisco Nunes Souza Neto2, Emerson Rodrigues de Camargo2, Marcelle Danelon3. 1. Department of Pediatric Dentistry and Public Health, São Paulo State University (Unesp), School of Dentistry, Araçatuba, Rua José Bonifácio 1193, Araçatuba, 16015-050, São Paulo, Brazil. 2. LIEC-Department of Chemistry, Federal University of São Carlos (UFSCar), Rodovia Washington Luís, São Carlos, 13565-905, São Paulo, Brazil. 3. Department of Pediatric Dentistry and Public Health, São Paulo State University (Unesp), School of Dentistry, Araçatuba, Rua José Bonifácio 1193, Araçatuba, 16015-050, São Paulo, Brazil. marcelledanelon@hotmail.com.
Abstract
OBJECTIVE: This study evaluated the effect of toothpastes containing 1100 ppm F associated with nano-sized sodium hexametaphosphate (HMPnano) on enamel demineralization in vitro using a pH-cycling model. DESIGN: Bovine enamel blocks (4 mm × 4 mm, n = 72) selected by initial surface hardness (SHi) were randomly allocated into six groups (n = 12), according to the test toothpastes: without fluoride or HMPnano (Placebo), 550 ppm F (550F), 1100 ppm F (1100F), 1100F plus HMPnano at concentrations of 0.25% (1100F/0.25%HMPnano), 0.5% (1100F/0.5%HMPnano), and 1.0% (1100F/1.0%HMPnano). Blocks were treated 2×/day with slurries of toothpastes and submitted to five pH cycles (demineralizing/remineralizing solutions) at 37 °C. Next, final surface hardness (SHf), integrated loss subsurface hardness (ΔKHN), integrated mineral loss (gHAp × cm-3), and enamel fluoride (F) concentrations were determined. Data were analyzed by ANOVA and Student-Newman-Keuls test (p < 0.001). RESULTS: Toothpaste with 1100F/0.5%HMPnano led to the lowest mineral loss and the highest mineral concentration among all groups, which were 26% (SHf) and 21% (ΔKHN) lower and ~58% higher (gHAp × cm-3) when compared to 1100F (p < 0.001). Similar values of enamel F were observed for all fluoridated toothpastes (p > 0.001). CONCLUSION: The addition of 0.5%HMPnano to a 1100 F toothpaste significantly enhances its effects against enamel demineralization when compared to its counterpart without HMPnano in vitro. CLINICAL SIGNIFICANCE: Toothpaste containing 1100 ppm F associated with HMPnano has a higher potential to reduce the demineralization compared to 1100 ppm F. This toothpaste could be a viable alternative to patients at high risk of caries.
OBJECTIVE: This study evaluated the effect of toothpastes containing 1100 ppm F associated with nano-sized sodium hexametaphosphate (HMPnano) on enamel demineralization in vitro using a pH-cycling model. DESIGN:Bovine enamel blocks (4 mm × 4 mm, n = 72) selected by initial surface hardness (SHi) were randomly allocated into six groups (n = 12), according to the test toothpastes: without fluoride or HMPnano (Placebo), 550 ppm F (550F), 1100 ppm F (1100F), 1100F plus HMPnano at concentrations of 0.25% (1100F/0.25%HMPnano), 0.5% (1100F/0.5%HMPnano), and 1.0% (1100F/1.0%HMPnano). Blocks were treated 2×/day with slurries of toothpastes and submitted to five pH cycles (demineralizing/remineralizing solutions) at 37 °C. Next, final surface hardness (SHf), integrated loss subsurface hardness (ΔKHN), integrated mineral loss (gHAp × cm-3), and enamel fluoride (F) concentrations were determined. Data were analyzed by ANOVA and Student-Newman-Keuls test (p < 0.001). RESULTS: Toothpaste with 1100F/0.5%HMPnano led to the lowest mineral loss and the highest mineral concentration among all groups, which were 26% (SHf) and 21% (ΔKHN) lower and ~58% higher (gHAp × cm-3) when compared to 1100F (p < 0.001). Similar values of enamel F were observed for all fluoridated toothpastes (p > 0.001). CONCLUSION: The addition of 0.5%HMPnano to a 1100 F toothpaste significantly enhances its effects against enamel demineralization when compared to its counterpart without HMPnano in vitro. CLINICAL SIGNIFICANCE: Toothpaste containing 1100 ppm F associated with HMPnano has a higher potential to reduce the demineralization compared to 1100 ppm F. This toothpaste could be a viable alternative to patients at high risk of caries.