Effect of fluoride gels with nano-sized sodium trimetaphosphate on the in vitro remineralization of caries lesions

• Published in: Journal of applied oral science Vol. 31; p. e20230155
• Main Authors: Nagata, Mariana Emi, Delbem, Alberto Carlos Botazzo, Báez-Quintero, Liliana Carolina, Danelon, Marcelle, Sampaio, Caio, Monteiro, Douglas Roberto, Wiegand, Annette, Pessan, Juliano Pelim
• Format: Journal Article
• Language: English
• Published: Brazil Faculdade De Odontologia De Bauru - USP 01.01.2023; University of São Paulo
• Subjects: Dental Enamel; DENTISTRY, ORAL SURGERY & MEDICINE; Fluorides; Nanoparticles; Nanotechnology; Original; Phosphates; Phosphates; Nanoparticles; Fluorides; Dental Enamel; Nanotechnology
• ISSN: 1678-7757; 1678-7765; 1678-7765
• DOI: 10.1590/1678-7757-2023-0115

To evaluate the effects of fluoride (F) gels supplemented with micrometric or nano-sized sodium trimetaphosphate (TMPmicro and TMPnano, respectively) on the in vitro remineralization of caries-like lesions. Bovine enamel subsurface lesions (n=168) were selected according to their surface hardness (SH) and randomly divided into seven groups (n=24/group): Placebo (without F/TMP), 4,500 ppm F (4500F), 4500F + 2.5% TMPnano (2.5% Nano), 4500F + 5% TMPnano (5% Nano), 4500F + 5% TMPmicro (5% Micro), 9,000 ppm F (9000F), and 12,300 ppm F (Acid gel). The gels were applied in a thin layer for one minute. Half of the blocks were subjected to pH cycling for six days, whereas the remaining specimens were used for loosely- (calcium fluoride; CaF2) and firmly-bound (fluorapatite; FA) fluoride analysis. The percentage of surface hardness recovery (%SHR), area of subsurface lesion (ΔKHN), CaF2, FA, calcium (Ca), and phosphorus (P) on/in enamel were determined. Data (log10-transformed) were subjected to ANOVA and the Student-Newman-Keuls' test (p<0.05). We observed a dose-response relation between F concentrations in the gels without TMP for %SHR and ΔKHN. The 2.5% Nano and 5% Micro reached similar %SHR when compared with 9000F and Acid gels. For ΔKHN, Placebo and 5% Nano gels had the highest values, and 5% Micro, 2.5% Nano, 9000F, and Acid gels, the lowest. All groups had similar retained CaF2 values, except for Placebo and Acid gel. We verified observed an increase in Ca concentrations in nano-sized TMP groups. Regarding P, TMP groups showed similar formation and retention to 9000F and Acid. Adding 2.5% nano-sized or 5% micrometric TMP to low-fluoride gels lead to enhanced in vitro remineralization of artificial caries lesions.