Efficacy of the self-assembling peptide P11-4 in constructing a remineralization scaffold on artificially-induced enamel lesions on smooth surfaces

Comparative evaluation of remineralization potential of novel bioactive agents on eroded enamel lesions: A single-blinded in vitro study

Objective

The escalating prevalence of noncarious tooth wear stands as a critical concern in the backdrop of evolving lifestyles and dietary patterns. Dental erosion, a progressive condition induced by both endogenous and exogenous acidic influences, directly impacts enamel integrity, resulting in surface loss. The contemporary surge in carbonated beverage consumption further exacerbates this erosive milieu, underscoring the urgency for dental practitioners to adopt meticulous treatment strategies. Existing literature underscores a noteworthy 94% reduction in tooth erosion risk for individuals abstaining from sweetened soft beverages, emphasizing the imperative for a well-devised remineralization protocol to counter demineralized surfaces.

Methodology

Seventy-three enamel specimens were taken. Forty samples were subjected to pre-operative hardness testing, and five samples were subjected to baseline EDX evaluation followed by grouping of samples (Group 1 = control Group; Group 2 = casein phosphopeptide-amorphous calcium phosphate fluoride [CPP-ACPF] Group; Group 3 = Biomin F Group; and Group 4 = self-assembling peptide [SAP] P-114 Group). A demineralization-remineralization cycle was carried out for 5 days followed by testing through Vickers Microhardness Tester, EDX Evaluation, and Scanning Electron Microscopy (SEM) Imaging. Statistical analysis was performed using one-way analysis of variance followed by intergroup analysis using Tukey's post hoc test with SPSS software 25.0 version.

Results

The mean percentage change in microhardness values was 30.05% in Group 1, 24.21% in Group 2, 18.85% in Group 3, and 12.08% in Group 4. The mean Ca/P ratio of samples tested through EDAX was 2.20 at baseline, 1.40 in Group 1 (Control Group), 1.62 in Group 2 (CPP-ACPF), 1.82 in Group 3 (Biomin F), and 2.01 in Group 4 (SAP-P114). Postintervention values were statistically significant from baseline values in both parameters.

Conclusion

Curodont Protect exhibits superior efficacy, offering valuable insights for future in vivo studies and clinical applications. The multifaceted evaluation, encompassing microhardness testing, SEM analysis, and EDXS assessment, contributes to a nuanced interpretation of the agents' impact, paving the way for informed decisions in clinical practice and future research endeavors.

A Comparison of the Enamel Remineralisation Potential of Self-Assembling Peptides

BACKGROUND

The aim of this research was to compare the efficacy of the remineralising potential of self-assembling peptides (SAPs): Curodont Repair (P11-4), P26, and leucine-rich amelogenin peptides (LRAP) with the standard 5% NaF varnish (Duraphat) on early enamel caries lesions (EECLs).

METHODS

A demineralising solution (DS) was used to create artificial EECLs in human dental enamel specimens, which were randomly allocated to treatment groups: P11-4; P26 solution; LRAP solution; 5% NaF varnish; and deionised water (DIW). Each specimen was subjected to 8 days of pH cycling. Specimens from each test group were subjected to microcomputed tomography (micro-CT) and nanomechanical testing to assess mineral density (MD), hardness (H), and elastic modulus (EM) properties of sound, demineralised, and treated enamel.

RESULTS

The mean MD percentage gain was highest in the P26 and P11-4 groups, followed by the LRAP, 5% NaF varnish, and DIW groups. There were statistically significant differences amongst groups. In the outer layer of EECLs, the EM and H were highest in P26 and P11-4 groups, followed by the LRAP and 5% NaF varnish. In the inner layer of EECLs, the EM and H were highest in P11-4 and P26 groups, indicative of enhanced penetration and remineralisation of the deeper parts of the artificial EECLs.

CONCLUSIONS

P26 and P11-4 SAPs are more effective than 5% NaF varnish in remineralising the depth of EECLs.

Adhesion and whitening efficacy of P11-4 self-assembling peptide and HAP suspension after using NaOCl as a pre-treatment agent

Background

This study evaluated the adhesion and whitening efficacy of a mixture of hydroxyapatite and P11-4 self-assembling peptide (HAP-peptide) on bovine enamel after pre-treatment with low-concentrated sodium hypochlorite (NaOCl).

Methods

Fifty-two caries-free bovine incisors were selected. 50 teeth were randomly allocated to five groups (n = 10). The first group was treated with a mixture of 6.25 wt% HAP and 5 ml P11-4 peptide, using NaOCl 3% as pre-treatment. Second, third and fourth groups were treated with 6.25 wt% HAP, 5 ml P11-4 peptide, and NaOCl 3%, respectively. In the fifth group, only water was applied (control group). The color of samples was measured using a spectrophotometer (USB4000-VIS-NIR-ES, Ostfildern, Germany). To evaluate color changes, ΔE values were statistically analyzed. Finally, adherence of HAP particles on two enamel surfaces with and without pre-treatment with NaOCl was analyzed with SEM.

Results

It was observed that the ΔE of the HAP-peptide suspension after pre-treatment with NaOCl was significantly stronger than the control group. In contrast, the overall color changes of separate applications of HAP, peptide, and NaOCl did not differ notably from the control group. SEM observations confirmed that pre-treatment with NaOCl resulted in a more pronounced coverage of HAP on the enamel surface.

Conclusions

Pre-treatment with a low-concentrated NaOCl enhanced the adherence of the HAP layer on the enamel surface, resulting in a stronger whitening effect.

Trial registration

The peptide-HAP suspension is effective in improving tooth whiteness.

Effectiveness of Self-Assembling Peptide (P11-4) in Dental Hard Tissue Conditions: A Comprehensive Review

The limitations on the use of fluoride therapy in dental caries prevention has necessitated the development of newer preventive agents. This review focusses on the recent and significant studies on P11-4 peptide with an emphasis on different applications in dental hard tissue conditions. The self-assembling peptide P11-4 diffuses into the subsurface lesion assembles into aggregates throughout the lesion, supporting the nucleation of de novo hydroxyapatite nanocrystals, resulting in increased mineral density. P11-4 treated teeth shows more remarkable changes in the lesion area between the first and second weeks. The biomimetic remineralisation facilitated in conjunction with fluoride application is an effective and non-invasive treatment for early carious lesions. Despite, some studies have reported that the P11-4 group had the least amount of remineralised enamel microhardness and a significantly lower mean calcium/phosphate weight percentage ratio than the others. In addition, when compared to a low-viscosity resin, self-assembling peptides could neither inhibit nor mask the lesions significantly. Moreover, when it is combined with other agents, better results can be achieved, allowing more effective biomimetic remineralisation. Other applications discussed include treatment of dental erosion, tooth whitening and dentinal caries. However, the evidence on its true clinical potential in varied dental diseases still remains under-explored, which calls for future cohort studies on its in vivo efficacy.

Remineralization effects of self-assembling peptide P11 -4 associated with three materials on early enamel carious lesions: An in vitro study

The aim of this study was to assess the remineralization of enamel caries lesions using the self-assembling peptide P11 -4 associated with different materials. Artificial early enamel lesions were prepared on 154 primary teeth. The samples were randomly divided into eight groups: (1) control, (2) P11 -4, (3) fluoridate toothpaste (FT), (4) P11 -4 + FT, (5) casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), (6) P11 -4 + CPP-ACP, (7) fluoridate bioactive glass toothpaste (BT), and (8) P11 -4 + BT. The surface enamel microhardness (EMH) and energy-dispersive X-ray spectroscopy (EDS) of the teeth were then measured at the baseline, after demineralization, and after 28 days of remineralization. The enamel surfaces were assessed by field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). The data were analyzed with one-way analysis of variance (ANOVA) (p < .05). EMH after demineralization was significantly lower than the baseline value (p < .001). The interventions led to an enhanced percentage of EMH recovery (%REMH), which was higher in Groups 6 and 7. There was no significant difference between Groups 3 and 4. Groups 1 and 2 had the lowest %REMH. The mean calcium/phosphate weight percentage ratio of P11 -4 was significantly lower than the others (p < .001). The FESEM and AFM images revealed mineral deposition on the eroded enamel and reductions in surface roughness in Groups 5 and 7.

Effects of different remineralizing agents on color stability and surface characteristics of the teeth following vital bleaching

The aim of the study was to investigate the effects of various remineralizing agents on the color stability and surface characteristics of the teeth after vital bleaching. The extracted 96 human incisors were used for the study. Initially, the samples were randomly divided into two groups and exposed to in-office and at-home bleaching agents. Then, the groups were divided into six subgroups (n = 8), including the control group did not undergo remineralization after bleaching, according to five remineralizing agents (Gelato APF Gel, Remin Pro, Tooth Mousse, MI Paste Plus, Curodont Protect). Surface roughness was assessed at baseline, after bleaching and remineralization procedures. Color measurements of the samples were obtained at baseline, after bleaching and then after immersion in the staining solution following remineralization process. Scanning electron microscopy and atomic force microscopy (AFM) analyzes were carried out in order to examine the morphological changes on the surface of the enamel. The independent t-test, paired-samples t-test, and one-way ANOVA was used to compare the data and post-hoc LSD test to compare the difference among the study groups (α = .05). Surface roughness increased following in-office and at-home bleaching in all groups, and reduced after application of remineralizing agents in all groups. Significant differences were found among the groups with respect to changes in surface roughness and color values following treatment with remineralizing agents (p <.05). AFM analyses revealed increased surface roughness after bleaching and a reduction of rough surfaces following treatment with remineralizing agents. Remineralizing agents can be used to reduce postbleaching increase in surface roughness and to maintain color stability after bleaching.

Efficacy of a self-assembling peptide to remineralize initial caries lesions - A systematic review and meta-analysis

INTRODUCTION/OBJECTIVES

The present review systematically analyzed clinical studies investigating the efficacy of self-assembling peptides (SAP) to reduce initiation of or to remineralize initial caries lesions.

DATA

Prospective controlled (non-)randomized clinical trials investigating the efficacy of a self-assembling peptide compared to any other (placebo) treatment or untreated/standard control. Outcomes were visual analog scale (VAS), laser fluorescence, ICDAS score or morphometric measurements.

SOURCES

Three electronic databases (Central, PubMed, Ovid EMBASE) were screened. No language or time restrictions were applied.. Risk of Bias and level of evidence was graded using Risk of Bias 2.0 tool and Grade Profiler 3.6.

STUDY SELECTION/RESULTS

Seven studies with 508 teeth being affected in 294 patients were included. All studies were randomized controlled trials (RCT), five with a split-mouth and two with a parallel-arm design. Meta-analysis could be performed for SAP (plus fluoride varnish (FV)) vs. no treatment (plus FV) (control treatment). Depending on the outcome after up to 12 months SAP showed a significantly higher optical improvement than the control treatment (laser fluorescence: Standardized Mean Difference (SMD)[95 %CI] = -0.87[-1.39,-0.34; VAS: Mean Difference (MD)[95 %CI] = -35.38[-43.13,-27.64]) or no significant difference could be observed (ICDAS/activity score; Relative Risk (RR)[95 %CI] = 0.6[0.21,1.74]; morphometric measurements: SMD[95 %CI] = -1.95[-4.54,0.65]). Level of evidence was very low for all 4 outcomes. Furthermore, six studies showed a high risk of bias and six studies were (partially) funded by the manufactures of the tested products.

CONCLUSION

Based on a low number of clinical trials with relatively short follow up-periods and high risks of bias, self-assembling peptides may be a viable option to remineralize enamel caries.

CLINICAL SIGNIFICANCE

Self-assembling peptides may be a viable option to remineralize enamel caries. However, results should be interpretated with caution due the low number of clinical trials, the short follow-up periods and the limiting grade of evidence.

Self-assembling peptide P11-4 in remineralization of enamel caries - a systematic review of in-vitro studies

OBJECTIVE

The present systematic review was conducted to investigate the effect of the self-assembling peptide (SAP) - P₁₁-4 in the remineralization of enamel caries.

MATERIAL AND METHODS

The systematic search for studies was conducted through CINAHL, EMBASE, MEDLINE, Scopus, PsychINFO, and various key journals. This review was conducted in adherence to PRISMA standards and was registered in PROSPERO with registration number CRD42019110156. The methodological quality of the studies was graded through Cochrane's tool of risk of bias in non-randomized studies - of interventions (ROBINS-I).

RESULTS

In total, 91 studies were identified for screening, and 12 studies were eligible. Ten studies showed effective enamel remineralization with P₁₁-4 compared to controls. One study showed a combination of P₁₁-4 with fluoride varnish or Casein Phosphopeptide-Amorphous Calcium Phosphate Fluoride (CPP-ACPF) leads to significantly higher remineralization compared to P₁₁-4 alone. Quality assessment of study showed 6 (50%) studies as medium risk of bias and 6 (50%) studies as low risk of bias.

CONCLUSION

To conclude, the present study results showed SAP- P₁₁-4 is effective in the remineralization of enamel caries.

Effectiveness of Self-assembling Peptide P11-4 Compared to Tricalcium Phosphate Fluoride Varnish in Remineralization of White Spot Lesions: A Clinical Randomized Trial

Background

Fluoride varnish with therapeutic tricalcium phosphate formulas such as Clinpro™ varnish has shown greater tendency in treating white spot lesions (WSLs) by inhibiting the progression of initial enamel lesions through the mineral exchange. The self-assembling peptide SAP₁₁-4 (Curodont Repair, CDR) works on a different scale in treating WSLs by mimicking the enamel matrix and aiming to guided enamel regeneration.

Aim

To quantitatively and qualitatively compare the effectiveness of the SAP₁₁-4 vs tricalcium posphate fluoride (TCPF) in remineralization of WSLs in young permanent teeth.

Materials and methods

Nine healthy patients were enrolled in this study. The trial was performed on 40 young permanent teeth in the initial demineralization stage. Teeth were randomly assigned to receive either TCPF (group I) or SAP₁₁-4 (group II). Lesions were assessed at pretreatment, 3, and 6 months posttreatment quantitatively per laser fluorescence DIAGNOdent pen and qualitatively through the International Caries Detection and Assessment System (ICDAS) II.

Results

The result of the current study revealed a significant quantitative and qualitative increase in remineralization of WSLs in both groups and over time intervals. However, the WSL recovery was significantly better in the self-assembling peptide group, reflecting an excellent remineralization potential of the WSLs by the SAP₁₁-4 compared to TCPF varnish.

Conclusion

Both TCPF and SAP₁₁-4 were effective in treating WSLs. However, the success of guided enamel regeneration by the SAP₁₁-4 through the biomineralization has proven superiority of this material compared to TCPF.

Clinical significance

Early detection of WSLs and minimal intervention through remineralizing agents can limit unnecessary tissue loss, further caries progression, and consequently prevent further harm to the patients.

How to cite this article

Kobeissi R, Badr SBY, Osman E. Effectiveness of Self-assembling Peptide P₁₁-4 Compared to Tricalcium Phosphate Fluoride Varnish in remineralization of White Spot Lesions: A Clinical Randomized Trial. Int J Clin Pediatr Dent 2020;13(5):451-456.

An in-vivo Intraoral Defect Model for Assessing the Use of P11-4 Self-Assembling Peptide in Periodontal Regeneration

Periodontal disease is one of the most common diseases worldwide. It has a significant impact on oral health and subsequently the individual’s quality of life. However, optimal regeneration of periodontal tissues, using current treatments, has yet to be achieved. Peptide self-assembly has provided a step-change in nanobiotechnology and regenerative medicine fields. Our aim was to investigate the effects of a self-assembling peptide (SAP; P₁₁-4) on periodontal regeneration in a preclinical model. Twenty-six bilateral maxillary critical-sized periodontal defects were created surgically in 13 rats. Defects on one side of the mouth were filled with P₁₁-4 hydrogel; the contra-lateral defect was untreated (control). Rats were sacrificed immediately post-surgery (time 0) and after 2 and 4 weeks. Retrieved maxillae were processed for histological, immunohistochemical, and histomorphometric assessments. The results of histological analysis showed greater organization of periodontal fibers in defects treated with P₁₁-4, at both time points, when compared to untreated defects. Histomorphometry showed that treated defects had both a significant increase in functional periodontal ligament length and a reduction in epithelial down growth after 4 weeks. At 2 weeks, treated defects showed a significant increase in expression of osteocalcin and osteoprotegerin as judged by immunohistochemistry. Also, a significantly higher osteoprotegerin/RANKL ratio was shown in treated defects. In conclusion, the results demonstrated enhanced regeneration of periodontal tissues when SAP P₁₁-4 was used to fill periodontal defects in rats. The findings of this study suggest that SAP P₁₁-4 is a promising novel candidate for periodontal regenerative therapy. Further investigations are required for optimization before clinical use.

Impact of self-assembling peptides in remineralisation of artificial early enamel lesions adjacent to orthodontic brackets

Enamel demineralisation can occur as a side effect during orthodontic treatment with fixed appliances. This study aimed to evaluate the efficacy of the self-assembling peptide P11-4 for remineralisation combined with fluorides, compared to application of fluoride varnish alone. De- and remineralisation was assessed by Quantitative light-induced fluorescence (QLF). Orthodontic brackets were bonded on 108 human enamel samples and white spot lesions were created. The samples were allocated randomly into three groups: Group I received no treatment, group II had a single application of fluoride varnish (22,600 ppm), and group III was treated with P11-4 following a single application of fluoride varnish. Quantitative light-induced fluorescence (QLF) measurements were performed at baseline, after demineralisation and after storage in remineralisation solution for 7 and 30 days. Non-parametric tests (Kruskal-Wallis test and Friedman test) were used for further analysis. After demineralisation, all samples showed a median ΔF -9.38% ± 2.79. After 30 days median ΔF values were as followed: group I = -9.04% ± 2.51, group II = -7.89 ± 2.07, group III = -6.08% ± 2.79). The median ΔF values differed significantly between all groups at all investigation times (p < 0.00001). Application of P11-4 with fluoride varnish was superior to the use of fluorides alone for remineralisation of enamel adjacent to brackets.

Effect of the caries-protective self-assembling peptide P11-4 on shear bond strength of metal brackets

Purpose

During orthodontic treatment with fixed appliances, demineralization around brackets often occurs. The aim of this in vitro study was to investigate the effect of the caries-protective self-assembling peptide P11‑4 (SAP P11-4) on the shear bond strength of metal brackets.

Methods

In all, 45 extracted human wisdom teeth were available for the study. The teeth were randomly divided into 3 groups (each n = 15) and pretreated as follows: test group 1: application of SAP P11‑4 (Curodont Repair, Windisch, Switzerland) and storage for 24 h in artificial saliva; test group 2: application of SAP P11‑4; control group: no pretreatment with SAP P11‑4. A conventional metal maxillary incisor bracket (Discovery, Dentaurum, Ispringen) was adhesively bonded to each buccal surface. The shear bond strength was tested according to DIN 13990. After shearing, the Adhesive Remnant Index (ARI) was determined microscopically (10 × magnification). Analysis of variance (ANOVA) was used to check the groups for significant differences (α = 0.05). The distribution of the ARI scores was determined with the χ ² test.

Results

There was no significant difference in shear forces between the groups (p = 0.121): test group 1 = 17.0 ± 4.51 MPa, test group 2 = 14.01 ± 2.51 MPa, control group 15.54 ± 4.34 MPa. The distribution of the ARI scores between the groups did not vary (p-values = 0.052–0.819).

Conclusion

The application of the caries protective SAP P11‑4 before bonding of brackets did not affect the shear bond strength. Therefore, pretreatment of the enamel surface with SAP P11‑4 shortly before bracket insertion can be considered.

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

This study aimed to evaluate the effect of self-assembling peptide P11-4 (SAP) in the therapy of initial smooth surface caries (white spot lesions, WSL) following orthodontic multibracket treatment. Twenty-three patients (13f/10m; average age 15.4 years) with at least two teeth with WSL were recruited for the randomised controlled clinical trial with split-mouth design. In opposite to the control teeth, the test teeth were treated with SAP on Day 0. The primary endpoint was the impedance measurement of WSL using customised tray to ensure reproducibility of the measurement location. The secondary endpoint was the morphometric measurement of WSL using a semi-automated approach to determine the WSL size in mm2. Treatment effects were adjusted for site-specific baseline values using mixed models adapted from the cross-over design. Test WSL showed a mean baseline impedance value of 46.7, which decreased to 21.1, 18.4, and 19.7 after 45, 90, and 180 days, respectively. Control WSL showed a mean baseline value of 42.0, which decreased to 35.0, 29.5, and 33.7, respectively. The overall treatment contrast was -13.7 (95% CI: -19.6 - -7.7; p < 0.001). For the secondary endpoint, the test WSL size decreased from 8.8 at baseline to 6.5 after 180 days. The control WSL decreased from 6.8 to 5.7, respectively. The related treatment contrast was -1.0 in favour of test WSL (95% CI: -1.6 - -0.5; p = 0.004). The treatment of initial carious lesions with self-assembling peptide P11-4 leads to superior remineralisation of the subsurface lesions compared with the control teeth.

Randomized Clinical Trial investigating Self-Assembling Peptide P11-4 for Treatment of Early Occlusal Caries

Non-invasive caries treatment is a major focus in modern dentistry. The present study was designed to evaluate the effectiveness of monomeric self-assembling peptide P₁₁-4 (SAP P₁₁-4) in combination with fluoride varnish or polymeric self-assembling peptide matrix (SAPM) in treatment of non-cavitated occlusal caries. Ninety children and adolescents were included in this randomized, gold-standard-controlled clinical trial. Test Group 1 received SAP P₁₁-4 and twice fluoride varnish at baseline and Day 180, Test Group 2 received SAP P₁₁-4 on baseline and twice weekly SAPM (home-application), and Control Group received fluoride varnish on baseline and Day 180. Caries progression was measured by laser fluorescence, Nyvad Caries Activity, ICDAS-II-codes, and investigator assessments. Laser fluorescence changes demonstrated superior results for Test Group 1 and 2, as values decreased compared to an increase for the Control Group (p < 0.0005). ICDAS-II codes at Day 360 showed partial regression for Test Group 1 (6.7%) and Test Group 2 (20.0%) and partial progression for Control Group (23.3%) (p < 0.01). Nyvad Caries Activity yielded superior caries inactivation for Test Groups, compared to Control Group (p = 0.002). This trial showed that SAP P₁₁-4, applied either in combination with fluoride varnish or twice weekly SAPM, was a superior treatment for early caries compared to fluoride varnish alone.

Complementary remineralizing effect of self-assembling peptide (P11-4) with CPP-ACPF or fluoride: An in vitro study

Background

Self-assembling peptide has been recently introduced to promote hard tissue regeneration for treating early non-cavitated carious lesions. This study investigates the efficacy of biomimetic self-assembling peptide (P11-4) on enamel remineralization combined with CPP-ACPF or fluoride.

Material and Methods

Artificial enamel lesions were created on buccal surface of 60 specimens and were randomly assigned to six groups according to the remineralizing agent: G1-(Control, artificial saliva), G2-(Fluoride varnish), G3-(CPP-ACPF varnish), G4-(Self-assembling peptide), G5-(Self-assembling peptide+fluoride varnish), G6-(Self-assembling peptide+CPP-ACPF varnish). All products were applied according to manufacturer’s instructions and specimens were stored in a daily renewed artificial saliva. Surface microhardness (SMH) and scanning electron microscope (SEM) were assessed at baseline, after demineralization, 1 week and 4 weeks storage. SMH values were analyzed using ANOVA and Tukey’s post-hoc test.

Results

The highest statistically significant SMH values were found in G6 followed by G5, G4, G2 and G3 while the lowest values were found in G1. No statistically significant difference was found between G5 and G6. Also, no statistically significant difference was found between G2 and G3. SEM showed that G4, G5, G6 resulted in more pronounced remineralization, reversing the demineralized enamel fish scale pattern compared to G2 and G3 after 1 week and 4 week remineralization.

Conclusions

Complementary effect was obtained after combining self-assembling peptide with CPP-ACPF or fluoride showing the highest remineralizing potential early after 1 week and even after 4 weeks compared to when each agent used alone. Added benefits can be obtained through combining self-assembling peptide with other remineralzing agents allowing faster and enhanced regeneration of non-cavitated caries lesions.

Key words:Enamel regeneration, biomimetic remineralization, self-assembling peptide, CPP-ACPF, fluoride.

Randomised clinical trial investigating self-assembling peptide P11-4 in the treatment of early caries

OBJECTIVES

This prospective, randomised, split-mouth, clinical trial compared the efficacy of the self-assembling peptide P₁₁-4 to fluoride varnish in the treatment of early buccal carious lesions.

MATERIALS AND METHODS

Subjects presenting at least two clinically affected teeth were treated at D0 (day 0) and D90 with P₁₁-4 (test) or fluoride varnish (control). At D180, fluoride varnish was applied on all study lesions. Standardised photographs were taken at D0, D30, D90, D180 and D360 and blindly morphometrically assessed. Hierarchical linear models (HLM) under allowance of confounders were used to compare the decrease in size between test and control groups. The visual analog scale (VAS) and Global Impression of Change Questionnaire (GICQ) were used as clinical assessments.

RESULTS

Overall, 37 subjects (13-36 years) with 90 early carious lesions were included. HLM analysis showed a significant difference between test and control groups, indicating a decrease in test lesions and stabilisation of control lesions size (p = 0.001). The test lesion's mean size (SD) relative to baseline decreased to D30 = 0.936(0.127), D90 = 0.874(0.173), D180 = 0.844(0.215) and D360 = 0.862(0.352), whereas control lesions remained stable at D30 = 1.018(0.209), D90 = 1.013(0.207), D180 = 1.029(0.235) and D360 = 1.068(0.401). The effect sizes ranged from 0.47 to 0.82.

CONCLUSIONS

Within the limits of this study, it was shown that the size of early carious lesions treated with P₁₁-4 was significantly reduced; this result was superior to that of fluoride varnish treatment (DRKS00012941).

CLINICAL RELEVANCE

The self-assembling peptide P₁₁-4 is the first caries treatment approach aiming to regenerate decayed enamel. P₁₁-4 initiates formation of de novo hydroxyapatite in the depth of early carious lesions, adding a new advanced therapy option for preventive dentistry.

Current treatment modalities of orthodontically induced white spot lesions and their outcome - a literature review

Introduction

White spot lesion is a demineralization of the enamel that appears as a white spot on the surfaces of the tooth. The cause of this spot is determined by the activity of the bacterial plaque and it represents the initial stage of a carious lesion. This lesion is a common side effect for patients with fixed orthodontic appliances mainly because of the brackets' position that favors the accumulation of plaque that ultimately leads to the formation of the white spot.

Methods

We conducted a search on a single database, PubMed. "Orthodontic", "white spot lesions", "enamel demineralization treatment" and "remineralization" were the search terms used. We found 324 articles, but we took in consideration only the ones from the last 10 years, which resulted in 223 articles.

Results

The first step after research was article selection: first by scrutinizing the title and secondly by reviewing the abstracts or full texts. The exclusion criteria were: meta-analysis, reviews, original articles regarding prevention of white spot lesions and their prevalence or incidence. We included the articles that seemed relevant for the treatment of white spot lesions, made either on extracted teeth either on orthodontic patients. We found 75 articles to be eligible for this research and we eliminated 5 because of the lack of an abstract or full text and a further 22 were rejected because they did not fit the aforementioned criteria.

Conclusion

Although some traditional methods for the treatment of white spot lesions seem to have undesirable results, nowadays with new technologies and thorough investigations in nanotechnology, the eradication of the lesion appears to be short term.

Randomised in situ clinical trial investigating self-assembling peptide matrix P11-4 in the prevention of artificial caries lesions

The aim was to investigate the ability of self-assembling Peptide P11-4 Matrix (SAPM) to remineralize artificial initial caries lesions compared to the use of fluoride varnish. Volunteers were recruited for this randomised, cross-over in situ trial. Bovine specimens, half including orthodontic brackets, were recessed on the buccal aspects of mandibular appliances. Specimens included internal sound enamel control, a demineralised control and a part exposed during the in situ phase. Each phase lasted four weeks, followed by a one-week washout. Treatment groups were: A: negative control, no treatment,B: positive control, 22,600 ppm fluoride varnish,C: test group, 1,000 ppm SAPM. Laser fluorescence values (LF) were measured before/after demineralisation, and after the in situ period. Micro-CT analysis was used to assess mineral changes within the specimens after the in situ phase. In specimens without brackets, ΔLF values after in situ phase were: A: +5.28, B: +0.85, C: −2.89. Corresponding ΔLF for specimens with brackets were: A: +5.77, B: +1.30, C: −3.15. LF-values between groups significantly differed from each other (p < 0.0001) after the in situ phase. Micro-CT analysis yielded no significant difference among groups for specimens without brackets. For specimens with brackets, the test group showed significantly more remineralisation than the negative (p = 0.01) and positive control (p = 0.003). Within the limitations of the study, SAPM showed prevention of caries and remineralisation of enamel around orthodontic brackets.

Treatment of Carious Lesions Using Self-Assembling Peptides

Modern approaches in caries treatment involve lesion management without tissue removal. Regenerative medicine focuses on replacing damaged tissues with biologically similar tissues. This article discusses the scientific evidence and clinical results for self-assembling peptides in modern caries management. The biomimetic remineralization promoted by self-assembling peptide P11-4 has been proven in vitro as an effective therapy for initial caries. P11-4 was rationally designed to promote formation of hydroxyapatite on its surface. The formulation was optimized to ensure the ability of monomeric P11-4 to penetrate past the subsurface lesions and assembly into a biomatrix within. Furthermore, P11-4 has shown that it assembles into fibers within carious lesions, and promotes the remineralization thereof. In a recent clinical study, the safety and efficacy of P11-4 in treatment of initial caries were evaluated. The additional effect of the application of P11-4 (Curodont Repair) was compared to the application of fluoride varnish (Duraphat) alone in active occlusal initial caries lesions on erupting permanent molars. In the 3- and 6-month recalls, the test group showed, both in the laser fluorescence readings and in the clinical assessment of the caries stage and activity, significantly superior lesion regression compared to the control group. No adverse events, medical complications, or allergic reactions related to the treatments were reported. Clinical applicability of treatment was regarded as satisfactory. Patients were happy to receive noninvasive caries treatments. In conclusion, biomimetic mineralization facilitated by P11-4 in combination with fluoride may present a simple, safe, and effective noninvasive treatment for early carious lesions.

Application of the Self- Assembling Peptide P11-4 for Prevention of Acidic Erosion

The aim of this study was to use ultrasonography to evaluate the effect of the self-assembling peptide P11-4 on acid erosion prevention. Curodont Repair (CR), which includes peptide P11-4, was used. Rectangular prisms of bovine enamel (4×1×1 mm) were immersed in pure orange juice for a period of 5 minutes six times per day for 28 days. These samples were divided into four groups of six specimens each and treated differently for an additional period of 28 days: 1) baseline group specimens were stored in artificial saliva; 2) CR group specimens were exposed to curodont without acid challenge; 3) NCRA (no curodont+acid challenge) specimens were treated with orange juice without curodont exposure; and 4) CRA (CR+acid challenge) specimens were treated with curodont before treatment with orange juice. The propagation time of longitudinal ultrasonic velocity (UV) was measured. Ultrastructural observation of each tested enamel surface was carried out using field-emission scanning electron microscopy (SEM). The UV data were analyzed using two-way analysis of variance with time and treatment as confounding factors. Post hoc pairwise tests among groups were performed using the Tukey honestly significant difference test. The average UV in intact bovine enamel for the baseline group ranged from 4,483 to 4,549 m/s and did not vary significantly within the test period. The average ultrasonic velocity (UV) in all samples decreased after the initial erosion. The UV in NCRA decreased further over time. Increased UVs were found for CR and CRA. For CR and CRA, there was no significant difference in UV at the end of the experiment from the initial value before erosion. In the results of SEM observation, the CR and CRA groups had similar morphologic features in that etching patterns were not clearly due to precipitation between the enamel rods. From the results of this in vitro study, it might be concluded that applying enamel matrix derivatives and self-assembling peptides on erosive lesions can improve remineralization.

Progress Toward the Clinical Translation of Bioinspired Peptide and Protein Assemblies

Supramolecular materials composed of proteins and peptides have been receiving considerable attention toward a range of diseases and conditions from vaccines to drug delivery. Owing to the relative newness of this class of materials, the bulk of work to date has been preclinical. However, examples of approved treatments particularly in vaccines, dentistry, and hemostasis demonstrate the translational potential of supramolecular polypeptides. Critical milestones in the clinical development of this class of materials and currently approved supramolecular polypeptide therapies are described in this study. Additional examples of not-yet-approved materials that are steadily advancing toward clinical use are also featured. Spherical assemblies such as virus-like particles, designed protein nanoparticles, and spherical peptide amphiphiles are highlighted, followed by fiber-forming systems such as fibrillizing peptides, fiber-forming peptide-amphiphiles, and filamentous bacteriophages.

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

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 (NNB). 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, NNB, N0, N1, T0, and E0 showed significantly increased ΔZ and LD values after pH-cycling (p ≤ 0.003; paired t test). C0, C1, NNB, 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.

Assessment of Enamel Remineralisation After Treatment with Four Different Remineralising Agents: A Scanning Electron Microscopy (SEM) Study

INTRODUCTION

Decades of research has helped to increase our knowledge of dental caries and reduce its prevalence. However, according to World Oral Health report, dental caries still remains a major dental disease. Fluoride therapy has been utilised in a big way to halt caries progression, but has been met with limitations. This has paved the way for the development of newer preventive agents that can function as an adjunct to fluoride or independent of it.

AIM

The purpose of the present study was to evaluate the ability of Casein Phosphopeptide-Amorphous Calcium Phosphate Fluoride (CPP ACPF), Bioactive Glass (BAG), fluoride enhanced Hydroxyapatite (HA) gel and self-assembling peptide P₁₁-4 to remineralise artificial carious lesions in enamel in vitro using a 30 day pH cycling model through surface microhardness analysis and SEM.

MATERIALS AND METHODS

Sixty enamel samples were divided into five groups of 12 samples each. The control Group A consisted of intact enamel samples, Group B: CPP-ACPF (Tooth Mousse Plus), Group C: BAG (SHY- NM), Group D: fluoride enhanced HA gel (ReminPro) and Group E: Self-assembling peptide P₁₁-4 (Curodont Protect). All groups excluding the control group were subjected to demineralisation following which four of these groups were remineralised using the four remineralising agents. The treated groups were subjected to pH cycling over a period of 30 days. This was followed by assessment of surface microhardness and SEM for qualitative evaluation of surface changes. The results were analysed by One-Way Analysis Of Variance (ANOVA). Multiple comparisons between groups were performed by paired t-test and post-hoc Tukey test.

RESULTS

The results of the study revealed that remineralisation of enamel was the highest in samples of Group E (Self assembling peptide P₁₁-4) followed by Group B (CPP-ACPF), Group C (BAG) and Group D (fluoride enhanced HA gel). There was a significant difference (p<0.05) in the remineralising ability between the self assembling peptide P₁₁-4 group and BAG and fluoride enhanced HA gel group. Although no significant difference was observed between the self assembling peptide P₁₁-4 and CPP-ACPF group, the self assembling peptide P₁₁-4 remineralised the enamel lesions more effectively. SEM photomicrographs of the test groups demonstrated either amorphous crystals or particles scattered on the surface or lines of remineralisation along the prismatic borders.

CONCLUSION

Self assembling peptide P₁₁-4 demonstrated promising results by effectively and significantly remineralising the enamel lesions as compared to other test agents.

Biomimetic Remineralization of Carious Lesions by Self-Assembling Peptide

Caries is the most common disease in the world. Great efforts have been undertaken for prevention and to identify a regenerative treatment solution for dental caries. Self-assembling β-sheet forming peptides have previously shown to form 3-dimensional fiber networks supporting tissue regeneration. In particular, the self-assembling peptide P₁₁-4 has shown potential in the treatment and prevention of dental caries. It has previously been shown that application of monomeric P₁₁-4 solution to early carious lesions can increase net mineral gain by forming de novo hydroxyapatite crystals. The hypothesis for the mode of action was that monomeric self-assembling peptide P₁₁-4 diffuses into the subsurface lesion body and assembles therein into higher order fibrils, facilitating mineralization of the subsurface volume by mimicking the natural biomineralization of the tooth enamel, and it remains within the lesion body as a scaffold built-in by the newly formed hydroxyapatite. The aim of the present study was to investigate the mechanism of action of the self-assembling peptide P₁₁-4 supporting mineralization of carious enamel. By various analytical methods, it could be shown that the self-assembling peptide P₁₁-4 diffuses into the subsurface lesion, assembles into higher formed aggregates throughout the whole volume of the lesion, and supports nucleation of de novo hydroxyapatite nanocrystals and consequently results in increased mineral density within the subsurface carious lesion. The results showed that the application of self-assembling peptide P₁₁-4 can facilitate the subsurface regeneration of the enamel lesion by supporting de novo mineralization in a similar mode of action as has been shown for the natural formation of dental enamel.

Measuring the Remineralization Potential of Different Agents with Quantitative Light-Induced Fluorescence Digital Biluminator

Background

The aim of this study was to investigate the effectiveness of different remineralization agents by quantitative light-induced fluorescence digital Biluminator™ (QLF-D).

Methods

Artificial caries lesions were created, and the teeth were divided according to the tested materials: (i) distilled water, (ii) acidulated phosphate fluoride (APF), (iii) Curodont Repair (CR), (iv) ammonium hexafluorosilicate (SiF) and (v) ammonium hexafluorosilicate plus cetylpyridinium chloride (SiF + CPC). After treatment procedures, each of the samples was placed in artificial saliva. After demineralization and 1 and 4 weeks of remineralization procedures, fluorescence loss and lesion areas were measured with QLF-D. Data were statistically analyzed (α = 0.05).

Results

The fluorescence values of the demineralized enamel specimens treated with the various agents differed significantly compared with pretreatment values for both 1 and 4 weeks (p<0.05). At 4 weeks, the highest fluorescence gain was calculated in the CR, APF and SiF groups compared with the control (p<0.05).

Conclusions

APF, SiF and CR groups yielded greater remineralization ability than SiF + CPC and control groups.

Effectiveness of Fluorescence-based Methods in Monitoring Progression of Noncavitated Caries-like Lesions on Smooth Surfaces

Although there has been a significant decrease in caries prevalence in developed countries, the slower progression of dental caries requires methods capable of detecting and quantifying lesions at an early stage. The aim of this study was to evaluate the effectiveness of fluorescence-based methods (DIAGNOdent 2095 laser fluorescence device [LF], DIAGNOdent 2190 pen [LFpen], and VistaProof fluorescence camera [FC]) in monitoring the progression of noncavitated caries-like lesions on smooth surfaces. Caries-like lesions were developed in 60 blocks of bovine enamel using a bacterial model of Streptococcus mutans and Lactobacillus acidophilus. Enamel blocks were evaluated by two independent examiners at baseline (phase I), after the first cariogenic challenge (eight days) (phase II), and after the second cariogenic challenge (a further eight days) (phase III) by two independent examiners using the LF, LFpen, and FC. Blocks were submitted to surface microhardness (SMH) and cross-sectional microhardness analyses. The intraclass correlation coefficient for intra- and interexaminer reproducibility ranged from 0.49 (FC) to 0.94 (LF/LFpen). SMH values decreased and fluorescence values increased significantly among the three phases. Higher values for sensitivity, specificity, and area under the receiver operating characteristic curve were observed for FC (phase II) and LFpen (phase III). A significant correlation was found between fluorescence values and SMH in all phases and integrated loss of surface hardness (ΔKHN) in phase III. In conclusion, fluorescence-based methods were effective in monitoring noncavitated caries-like lesions on smooth surfaces, with moderate correlation with SMH, allowing differentiation between sound and demineralized enamel.

Ultrasonic assessment of the effects of self-assembling peptide scaffolds on preventing enamel demineralization

OBJECTIVES

This study evaluates the effect of self-assembling peptide P11-4 (Curodont Repair, CDR) on bovine enamel remineralization by measuring changes in ultrasonic propagation velocity.

METHODS

Six specimens per group were prepared by sectioning bovine teeth into enamel blocks. These blocks were then immersed in lactic acid buffer solution (pH = 4.75) for 10 min twice a day and stored in artificial saliva. Other specimens were first treated with CDR, followed by a 10-min immersion in the lactic acid buffer solution twice a day, before storage in artificial saliva. The propagation time of longitudinal ultrasonic waves was measured using a pulser/receiver. Six specimens were used for each treatment protocol. The obtained data were statistically analyzed using ANOVA followed by Tukey's honestly significant difference tests (α = 0.05). Specimens were observed using laser scanning microscopy and scanning electron microscopy.

RESULTS

Sonic velocity was found to decrease with time for specimens stored in the demineralizing solution. On the other hand, increases in sonic velocity were found for specimens treated with CDR. These specimens also exhibited signs of mineral deposition.

CONCLUSIONS

By measuring the ultrasonic propagation velocity, it can be concluded that CDR application has an ability to promote bovine enamel remineralization.