Effects of Self-Assembling Peptide P11-4, Fluorides, and Caries Infiltration on Artificial Enamel Caries Lesions in vitro

Abstract

The application of a self-assembling peptide on noncavitated caries lesions is supposed to be a feasible approach to facilitate remineralization and mask their unfavorable appearance. However, demineralizing conditions are common in the oral environment, so the aim of this pH-cycling study was to compare recommended and novel treatment methods regarding their ability to hamper demineralization and as a consequence mask artificial enamel caries lesions. Artificial caries lesions were prepared in bovine enamel and randomly allocated to 11 groups (n = 22). Treatments before pH-cycling were as follows: the application of a self-assembling peptide (Curodont™ Repair [C]), a low-viscosity resin (Icon® [I]), 2 fluoride solutions (10,000 ppm F^-: Elmex fluid [E] and 43,350 ppm F^-: Tiefenfluorid® [T]), and no intervention (N). During pH-cycling (28 days, 6 × 60 min demineralization/day) half of the specimens in each group were brushed (10 s; 2 ×/day) with either fluoride-free (named e.g., C₀) or NaF (1,100 ppm F^-; e.g., C₁) dentifrice slurry. In another subgroup specimens were pH-cycled but not brushed (N_NB). Differences in integrated mineral loss (ΔΔZ), lesion depth (ΔLD), and colorimetric values (ΔΔE) were calculated between values after pre-demineralization, surface treatment, and pH-cycling. Specimens of C₀, C₁, N_NB, N₀, N₁, T₀, and E₀ showed significantly increased ΔZ and LD values after pH-cycling (p ≤ 0.003; paired t test). C₀, C₁, N_NB, and N₀ showed significantly higher changes in ΔΔZ than E₁, I₀, I₁, and T₁ (p < 0.001; ANOVA). Significantly reduced colorimetric values could only be observed for I₁, I₀, E₁, and E₀ after treatment and after pH-cycling (p ≤ 0.027; paired t test). In conclusion, under the conditions chosen only the application of a low-viscosity resin could mask caries lesions significantly, whereas self-assembling peptides could neither inhibit lesion progression nor mask the lesions considerably.

Caries-Preventive Effect of NaF, NaF plus TCP, NaF plus CPP-ACP, and SDF Varnishes on Sound Dentin and Artificial Dentin Caries in vitro

“…To simulate these brushing procedures, controlled and constant linear strokes with a brushing force of 0.5 N were used. Although linear strokes could be observed in vivo [Ganss et al, 2009] and were used in vitro [Aykut-Yetkiner et al, 2014;Wierichs et al, 2017a], the adjusted brushing force was lower than that measured clinically (1.5-3 N [Ganss et al, 2009]) or in vitro (1.5-2.5 N [Aykut-Yetkiner et al, 2014]). Nonetheless, our (unpublished) prestudies indicate that in the pH cycling procedure used, machine forces higher than 0.5 N would result in dentinal surface abrasions.…”

“…pH Cycling Conditions A computer-controlled pH cycling and brushing machine developed by our group and previously described [Wierichs et al, 2017a] was used to simulate oral pH fluctuation patterns and daily oral care. pH cycling lasted 14 days, and conditions were chosen with a daily schedule of 6 cycles, where specimens were consecutively subjected to a demineralizing (120 min), a rinsing (30 s), a remineralizing (60 min), and again a rinsing (30 s) phase.…”

“…The microradiographs were digitalized with an image-analyzing system (Diskus software version 4.80; Hilgers, Königswinter, Germany) that is interfaced with a universal microscope (Leica DMRX; Leica, Germany) and a personal computer. TMR software (version 5.25 by Joop de Vries, Groningen, The Netherlands) was used to calculate the mineral loss (ΔZ baseline / ΔZ pH cycle ) and lesion depth (LD baseline /LD pH cycle ) and to record the maximum (SZ max,baseline /SZ max,pH cycle ) and minimum (SZ min,baseline / SZ min,pH cycle ) mineral density of the lesion surface zone before and after pH cycling [Lippert et al, 2015;Wierichs et al, 2017a].…”

“…This color system has been widely used to analyze optical changes on enamel surfaces [Paris et al, 2013;Wierichs et al, 2017a] but not on dentin surfaces. Nonetheless, colorimetric analyses were used, as in up to 97% of the lesions after the application of SDF a black discoloration was reported [Yee et al, 2009].…”

Effect of self-assembling peptide P11-4 on orthodontic treatment-induced carious lesions

“…Although buccal carious lesions chosen in order to quantitatively assess the effect of the treatment are rare outside the orthodontics, the clinical significance of the results relates to the treatment of caries in general. Thus, the aesthetic shortcomings of the SAP P 11 -4 treatment 46 are neglectable for almost all of the initial carious lesions as most clinically relevant caries develops in proximal or occlusal sites and if buccal lesions occur, they are mostly positioned on premolars and molars.…”