A SEM and non-contact surface white light profilometry in vivo study of the effect of a crème containing CPP-ACP and fluoride on young etched enamel

Synthetic amorphous calcium phosphates (ACPs): preparation, structure, properties, and biomedical applications

Amorphous calcium phosphates (ACPs) represent a metastable amorphous state of other calcium orthophosphates (abbreviated as CaPO₄) possessing variable compositional but rather identical glass-like physical properties, in which there are neither translational nor orientational long-range orders of the atomic positions. In nature, ACPs of a biological origin are found in the calcified tissues of mammals, some parts of primitive organisms, as well as in the mammalian milk. Manmade ACPs can be synthesized in a laboratory by various methods including wet-chemical precipitation, in which they are the first solid phases, precipitated after a rapid mixing of aqueous solutions containing dissolved ions of Ca²⁺ and PO₄^3- in sufficient amounts. Due to the amorphous nature, all types of synthetic ACPs appear to be thermodynamically unstable and, unless stored in dry conditions or doped by stabilizers, they tend to transform spontaneously to crystalline CaPO₄, mainly to ones with an apatitic structure. This intrinsic metastability of the ACPs is of a great biological relevance. In particular, the initiating role that metastable ACPs play in matrix vesicle biomineralization raises their importance from a mere laboratory curiosity to that of a reasonable key intermediate in skeletal calcifications. In addition, synthetic ACPs appear to be very promising biomaterials both for manufacturing artificial bone grafts and for dental applications. In this review, the current knowledge on the occurrence, structural design, chemical composition, preparation, properties, and biomedical applications of the synthetic ACPs have been summarized.

In Vitro Influence of Prophylaxis Cleaning on Enamel Remineralization with Casein Phosphopeptide-Amorphous Calcium Phosphate

Objectives

This randomized controlled in vitro 4-arm trial study aimed to study the remineralization potential of Recaldent™ and assess the effects of prophylaxis cleaning and MI Varnish^® on enhancing this remineralization potential.

Material and Methods

Sixty human teeth were randomly assigned into equal samples (A/B). Sample A was prophylactically cleaned, randomly divided into equal samples (1/2). Sample A1 received treatment with MI Varnish^® and Recaldent™ for 30 days. Sample A2 was treated similarly but without MI Varnish^®. Sample B did not receive prophylaxis cleaning and was divided into equal samples (1/2). Sample B1 was treated as A1 and sample B2 as A2. The teeth were examined for mineral composition at baseline, after the interventions (T1), and after prophylaxis cleaning (T2). Study outcomes were mineral content (% weight of carbon [C], phosphorus [P], calcium [Ca], oxygen [O], chlorine [Cl], sodium [Na] and silicon [Si]) and calcium-phosphorus ratio (Ca/P).

Results

All groups had similar mineral composition at baseline. At T1, sample B2 exhibited least P, Ca and Ca/P content. Samples A1 and B1 showed higher content of P and Ca, compared to B2 (A1 only exhibited higher Ca/P). Sample A2 exhibited lowest Cl and Na content. At T2, sample A1 exhibited lowest C, P, O and Si content (highest Ca/P). Sample A2 showed least Ca/P, and highest Na content.

Conclusions

Teeth treated by Recaldent™ proceeded by prophylaxis cleaning or MI Varnish^® showed remineralization, especially when receiving both interventions. This superior effect persisted even after a second cleaning. Further trials are necessary to provide conclusive evidence in humans.

Effectiveness of polyacrylic acid-bioactive glass air abrasion preconditioning with NovaMin remineralization on the microhardness of incipient enamel-like lesion

Background:

Bioactive glass (BAG) remineralization is a promising method for dental hard tissue regeneration. The aim of this study was to evaluate the microhardness of incipient enamel-like lesions with or without preconditioning by air abrasion using polyacrylic acid (PAA)-BAG before application of NovaMin remineralizing agent.

Materials and Methods:

Forty extracted human molars were selected, sectioned mesiodistally obtaining buccal and lingual halves, and embedded in resin molds. Specimens were randomly assigned to four groups (n = 10) according to the remineralization protocol: G1 (control, artificial saliva), G2 (preconditioning), G3 (NovaMin), and G4 (preconditioning and NovaMin). Enamel windows 4 mm × 4 mm were done on the buccal and lingual surfaces. Specimens were immersed in a daily renewed demineralizing solution to create white spot lesions. Remineralizing agents were applied according to the manufacturer's instructions, and specimens were stored in a daily renewed artificial saliva. Microhardness was assessed using Vickers hardness number (VHN) at baseline (positive control), after demineralization (negative control), and after 24-h and 1-month remineralization.

Results:

The preconditioning/NovaMin group after 1 month showed a statistically significant high VHN, with no statistically significant difference between it and the positive control. This was followed by the NovaMin group after 1 month, while the lowest VHN was found in the demineralized group, with no statistically significant difference between it and the preconditioning group, whether after 24 h or 1 month.

Conclusions:

Enamel preconditioning with PAA-BAG air abrasion play a major role in enhancement of remineralization when it is accompanied with NovaMin. Furthermore, an extended period of time had helped to attain more benefits from NovaMin remineralization.

Clinical Significance:

Enamel remineralization with NovaMin after conditioning by bioactive glass air abrasion, provides the patients with a fast and durable treatment of incipient enamel lesions, which would reduce the possibility of future progression of demineralization and caries occurrence.

Effects of treatment with three types of varnish remineralizing agents on the microhardness of demineralized enamel surface

Background

Remineralization of incipient caries is one of the goals in dental health care ,especially in pediatric dentistry. The present study aimed at comparing the effects of MI varnish (3M (United states)) , Nano paste( FGM(Brezil) ), 5% sodium fluoride varnish) DuraphatColgate (united states) ) on remineralization of enamel lesions.

Material and Methods

In this in-vitrostudy, 60 intact human pre-molars, were randomly allocated to four groups of 15. Baseline surface microhardness in three points in the center of the polished area was measured. After two days of immersion in demineralizing solution, microhardness of all samples was measured. Afterward, groups 1-3 under-went treatment with MI varnish, nano paste, 5% sodium fluoride varnish and then again microhardness was measured. The results were analyzed by one-way analysis of variance (ANOVA), repeated measures ANOVA, and Bonfreni table was used.

Results

Duraphat varnish in comparison with control group, significantly increased surface microhardness and in comparison with Nano and MI paste varnish groups significant differences was shown between groups. (P< 0.05). MI paste varnish and Nano paste similary showed more increases in surface microhardness in comparison with Duraphat varnish and control groups (P≈1).

Conclusions

According to the results of this study, all three varnishes, Duraphat , MI paste and Nano paste increase the enamel surface microhardness and remineralization of incipient caries. MI paste and Nano paste compared to Duraphat Varnish, significantly showed more increases in enamel surface microhardness but Nano paste and MI paste were almost the same. Key words:CPP-ACP, Nano varnish, fluoride varnish, microhardness, demineralization, remineralization.

Effectiveness of casein phosphopeptide-amorphous calcium phosphate-containing products in the prevention and treatment of white spot lesions in orthodontic patients: A systematic review

The purpose of the present systematic review was to evaluate the effectiveness of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP)-containing products in the prevention and treatment of active white spot lesions (WSL) in orthodontic patients. Searched the Scopus, PubMed, Web of Science, Cochrane, Virtual Health Language, ClinicalTrials, and Open Gray databases without limitations on the year or language of publication. We included controlled clinical trials with patients with fixed orthodontic appliances under the use of CPP-ACP-containing products compared to control, placebo, or other interventions in the prevention and treatment of WSL around orthodontic braces. Case reports, editorials, in vitro studies, annals of congress, and reviews were excluded. To assess the risk of bias, the revised version of the Cochrane tool for randomized trials (RoB 2.0) and Risk Of Bias In Non-randomized Studies for non-randomized trials were used. The biases were graded low, moderate, and high according to the tools used. Of the 599 articles found, 11 met the inclusion criteria. Of these, nine were randomized, controlled clinical trials and two were non-randomized. Two studies were considered to have moderate bias risk, and the most-used CPP-ACP presented form was a cream for topical applications. Although CPP-ACP-containing products did not differ from other fluoride products, they were able to reduce WSL and neutralize the pH around the orthodontic braces. Products containing CPP-ACP are effective in preventing and treating WSL around the braces. However, further studies with the same measurement method and periods of use, and other forms of presentation of CPP-ACP are needed.

Effect of dentifrice containing fTCP, CPP-ACP and fluoride in the prevention of enamel demineralization

OBJECTIVE

To evaluate the effect of different fluoride- and calcium- and/or phosphate-containing products on their ability to prevent enamel demineralization under pH cycling conditions.

MATERIAL AND METHODS

Enamel bovine specimens were assigned to the following groups: G1-MPP (MI Paste Plus, 0.2% NaF, Recaldent™, GC Corporation Tokyo, Japan); G2-FD (Crest™ Cavity Protection, 0.243% NaF, Procter & Gamble, USA); G3-CLP (Clinpro™ 5000, 1.1% NaF, 3M ESPE, USA); and G4-CO (Control without fluoride, Silica-based dentifrice; Daudt Ltda, Brazil). The specimens were soaked in demineralizing solution for 6 h and remineralizing solution for 18 h alternatively for 10 days. The toothpaste was prepared with deionized water in a 1:3 ratio (w/v) for three minutes daily. The solutions were renewed every 48 h. After cycling, enamel changes were analysed by percentage change of SMH (%SMH) and energy-dispersive X-ray spectroscopy (EDS). The %SMH value observed for G3-CLP (2.9 ± 39.2) was higher than that found in G4-CO (-13.0 ± 20.7), G1-MPP (-8.9 ± 20.9) and G2-FD (-3.9 ± 27.1). The %SMH was similar for all treatment groups (one-way ANOVA and Tukey's HSD; p < .05). The pH, Ca²⁺ and P_total in the remineralization solutions were not different among all groups (Kruskal-Wallis; p < .05). At 24 h, the Ca²⁺ concentration in the demineralization solution was significantly lower in G1-MPP. Ca²⁺ concentration increased in all groups after 48 h, except for G3-CLP. The EDX quantitative analysis showed that the atomic % of elements is lower level at G4-CO.

CONCLUSIONS

The Clinpro™ 5000 demonstrated having the most protective effect against demineralization; however, the % SMH was similar for all groups.

Influence of biofilm formation on the mechanical properties of enamel after treatment with CPP-ACP crème

The study aimed to investigate the effects of bacterial biofilms on changes in the surface microhardness of enamel treated with casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) with and without fluoride. Human enamel blocks with incipient caries-like lesions were divided into four groups of 13: G1: Saliva (Control); G2: fluoride dentifrice (Crest™, 1100 ppm as NaF); G3: CPP-ACP (MI Paste; Recaldent™); and G4: CPP-ACPF (MI Paste Plus; Recaldent™ 900 ppm as NaF). The specimens were soaked in demineralizing solution for 6 h and remineralized in artificial saliva for 18 h alternately for 10 days. The dentifrice was prepared with deionized water in a 1 : 3 ratio (w/w) or applied undiluted in the case of the CPP-ACP group. The surface microhardness (SMH) was evaluated at baseline, after artificial caries, after pH cycling and treatment with dentifrices, and after incubation in media with Streptococcus mutans for biofilm formation. The biofilms were exposed once a day to 2% sucrose and the biofilm viability was measured by MTT reduction. The percentage of change in surface microhardness (%SMHC) was calculated for each block. The data were analyzed by nonparametric test comparisons (α = 0.05). The %SMHC values observed in G2 were different from those of G1, G3, and G4 (p < 0.05). After biofilm formation, %SMHC was positive in G2 and G4 when compared to G1 and G3, but resistance to demineralization after biofilm formation was similar in all groups. In conclusion, the presence of biofilms did not influence the treatment outcomes of anticaries products.

Remineralizing potential of CPP-ACP creams with and without fluoride in artificial enamel lesions

BACKGROUND

This study evaluated the effect of pastes containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) with and without fluoride on enamel demineralization.

METHODS

Human enamel blocks were used and after incipient caries-like lesions were formed, they were assigned to four groups: G1 - saliva; G2 - MI Paste (Recaldent^TM ); G3 - MI Paste Plus (Recaldent^TM 900 ppm as NaF); and G4 - Crest^™ (1.100 ppm as NaF). The specimens were soaked in demineralizing solution for 6 hours and remineralized in artificial saliva for 18 hours alternatively for 10 days. The dentifrice was prepared with deionized water in a 1:3 proportion (w/w) or applied undiluted in the case of the CPP-ACP formula. Demineralized enamel changes were analysed by surface microhardness (SMH), 3D-profilometry and SEM. Data were analysed by non-parametric Kruskal-Wallis and Mann-Whitney test comparisons and one-way ANOVA and Tukey's HSD post hoc test (α = 0.05).

RESULTS

The SMH values observed in the G2 (47.8 ± 28.5) and G3 (53.6 ± 27.6) groups were different from that of G4 (90.2 ± 17.1), which were significantly higher than that found in G1 (39.4 ± 14.2). The %SMH was significantly lower in G4 when compared to G1 (p < 0.001) and G3 (p < 0.05).

CONCLUSIONS

MI Paste Plus demonstrated a greater protective effect against demineralization than MI Paste and showed smoother surfaces.

Is there a place for Tooth Mousse in the prevention and treatment of early dental caries? A systematic review

Background

It is important for Dental Professionals to consider the evidence for the effectiveness of the preventive strategies used to maintain good oral health and reduce the risk of caries in their patients. Whilst many of the traditional preventive activities, including the recommendation and use of fluoride products and the placement of fissure sealants have a wealth of clinical evidence to support their use, some of the newer preventive agents have a more limited evidence base. In order to investigate the level of scientific support behind one such technology, a systematic literature review was carried out to assess the effectiveness of Tooth Mousse® (MI Paste®) and Tooth Mousse Plus® (MI Paste Plus®) in the prevention and treatment of early dental caries.

Methods

A broad search strategy using Medline via OvidSP and EMBASE was performed in order to capture all published studies to related Casein Phosphopeptide-Amorphous Calcium Phosphate. In addition to the above searches the terms “CPP ACP” and “casein phosphopeptide amorphous calcium phosphate” were searched using PREMEDLINE and the Cochrane Central Register of Controlled Trials. Inclusion criteria were clinical trials of participants of any age, comparing the use of Tooth Mousse® (MI Paste®) or Tooth Mousse Plus® (MI Paste Plus®) to a routine oral care regimen and reporting recognised clinical outcome measures for early caries lesions. Only research studies in English were selected.

Results

7576 articles were identified, but the majority were duplicates. Once these were removed 172 articles were inspected and the focus on ‘CPP-ACP formulations of Tooth Mousse® (MI Paste®) and Tooth Mousse Plus® (MI Paste Plus®) resulted in 29 articles being selected, and of these 12 studies met the inclusion criteria and were considered acceptable for the systematic review.

Discussion

The overall findings of this review did not show any significant benefits of using Tooth Mousse® (MI Paste®) products over brushing with a fluoride toothpaste for the prevention of early dental caries. With regard to the regression of white spot lesions in orthodontic patients there is a tendency towards a benefit for the use of Tooth Mousse® (MI Paste®) but the quality of evidence is limited. There is a lack of evidence to support the use of Tooth Mousse Plus® (MI Paste Plus®) over Tooth Mousse® (MI Paste®) at this time.

Conclusion

This review suggests that further well-designed randomized controlled trials are required prior to the widespread recommendation of Tooth Mousse® products for the prevention and treatment of early dental caries in the general population.

Electronic supplementary material

The online version of this article (doi:10.1186/s12903-015-0095-6) contains supplementary material, which is available to authorized users.

SEM-Evaluation of enamel surfaces after orthodontic debonding: a 6 and 12-month follow-up in vivo study

The purpose of this in vivo study was to compare the morphology of the enamel surfaces before bracket bonding and 6 and 12 months after debonding. Replicas of thirty-two maxillary second premolars of 16 volunteers were made before bracket bonding (T0), after debonding (T1), 6 months (T2), and 12 months (T3) later. Scanning electron microscope (SEM) images of the labial enamel surfaces were taken at T0, T1, T2, and T3 at increasing magnifications and analyzed according to the enamel damage index EDI. Data evaluation by using Friedman test followed by Wilcoxon signed ranks test with Bonferroni adjustment did not reveal statistically significant differences in the mean EDI at T0, T2, and T3, whereas the mean EDI at T1 was significantly higher than at T0, T2, and T3 (p < 0.05). The debonding procedure tested in this study produces no clinically relevant enamel damage. These alterations are reversible indeed, as a progressive restoration to pretreatment condition is evident after 6 months already and even more after 12 months.

Does acid etching enhance remineralisation of arrested white spot lesions?

AIM

To investigate the effect of acid etching procedure on the remineralisation of white spot lesions (WSL) which had undergone an initial phase of arrest, and to compare between the effect of fluoride and/or CPP-ACP on remineralisation before and after acid etching.

STUDY DESIGN

In vitro study.

METHODS

WSL were prepared in vitro on 130 human enamel slabs which were allocated into four experimental groups (N = 30) and one control group (N = 10). Changes in mineral content were registered weekly by Quantitative Light Induced Fluorescence QLF. When changes had arrested (after 8 weeks), the enamel surface of 20 slabs in each group were acid etched. The remineralisation process was continued until it slowed down again (after 5 weeks).

RESULTS

Mean fluorescence gain was 13.7 ± 0.9% in the fluoride group, 16.5 ± 1.1% in the CPP-ACP group, and 11.4 ± 1.2% in the combination of fluoride and CPP-ACP group.

CONCLUSIONS

There was a tendency toward better remineralisation after acid etching but this did not reach a significant level; the effect of etching was more pronounced in the presence of fluoride. Although CPP-ACP seemed to give a steadier rate of remineralisation over time when compared with fluoride, the overall remineralisation in the regimens was similar. In this model, combined treatment of fluoride and CPP-ACP did not have an extra benefit over the fluoride or CPP-ACP alone.