Remineralization of enamel subsurface lesions using toothpaste containing tricalcium phosphate and fluoride: an in vitro µCT analysis

Abstract

Background This study aimed to compare the efficacies of experimental toothpastes containing functionalized tricalcium phosphate (fTCP) with and without fluoride for in vitro enamel remineralization under pH-cycling conditions. Methods To create artificial white spot lesions, 36 bovine enamel specimens were immersed in a demineralization solution for 10 days. During pH-cycling for 12 days, the specimens were divided into four groups based on the experimental toothpaste type used: (a) fTCP-free, fluoride-free (fTCP − F −); (b) fTCP-containing, fluoride-free (fTCP + F −); (c) fTCP-free, fluoride-containing (fTCP − F +); and (d) fTCP-containing, fluoride-containing (fTCP + F +). Micro-focus X-ray computed tomography (μCT) scans of all specimens were obtained before demineralization, after demineralization, and after pH-cycling. The mineral density and mineral loss (ΔZ) in the enamel subsurface lesions were measured and the percentage of remineralization (%R) was calculated from ΔZ after demineralization and pH-cycling. One-way ANOVA with Tukey’s test was used for statistical analysis of the %R values. The treated enamel surface was investigated via scanning electron microscopy (SEM). Results The fTCP − F − group presented with the lowest amount of mineral gain after pH-cycling. In contrast, the fTCP + F + group showed the highest degree of remineralization within all lesion parts. The %R was highest in the fTCP + F + group (38.2 ± 7.8, all P < 0.01). SEM revealed the presence of small crystals on the enamel rods in the fTCP + F − and fTCP + F + groups. Conclusions The experimental toothpaste containing fTCP and fluoride increased remineralization of the artificial enamel subsurface lesions during pH-cycling. Furthermore, fTCP and fluoride appear to act independently on the remineralization of enamel subsurface lesions, although they coexisted in one toothpaste type. Trial registration: This is not a human subject research.

Inhibitory effect of a gel paste containing surface pre-reacted glass-ionomer (S-PRG) filler on the cariogenicity of Streptococcus mutans

“…Bovine teeth are widely used to assess enamel decalcification and remineralization 22 – 24 . However, relatively few studies have used bovine enamel to evaluate the biofilm formation of S. mutans 25 , 26 .…”

Hydroxyapatite in Oral Care Products—A Review

“…In a study where the β-TCP structure was altered by combining with carboxylic acids and surfactants to generate functionalised β-TCP (fTCP), the toothpaste containing fTCP and fluoride increased remineralisation of the artificial enamel subsurface lesions during pH-cycling [48]. In another study, fTCP containing toothpaste effectively reduced white spot lesions (WSL) compared to 1000-ppm fluoridecontaining toothpaste [49]. However, an in situ study showed that the remineralisation efficacy of fTCP toothpaste was similar to that of fluoride toothpaste [50].…”

Application of β-Tricalcium Phosphate in Adhesive Dentin Bonding

“…Although many polymorphs exist, two polymorph phases (α and β) are primarily utilized as biomaterials [ 10 ]. In dentistry, both α-TCP and β-TCP possess wide-ranging clinical applications including (but not limited to) their use in a toothpaste to remineralize enamel subsurface lesions [ 11 ], in dental varnishes to reduce enamel demineralization [ 12 ], and in adhesives to improve their properties [ 13 ]. β-TCP was introduced in the early 1970s by Driskell and team primarily to treat bony defects [ 14 ].…”