Effect of fluoride, casein phosphopeptide-amorphous calcium phosphate and sodium trimetaphosphate combination treatment on the remineralization of caries lesions: An in vitro study

Efficacy of the Probiotic L. brevis in Counteracting the Demineralizing Process of the Tooth Enamel Surface: Results from an In Vitro Study

BACKGROUND

Enamel plays an essential role in protecting the underlying layers of the human tooth; therefore, preserving it is vital. This experimental study aimed to evaluate the potential ability of L. brevis to counteract the action of a demineralizing agent on dental enamel morphology and mineral composition in vitro.

METHODS

The sample consisted of 12 healthy human posterior teeth. The coronal portion of each tooth was subdivided into two equal parts longitudinally. The specimens were randomly divided into four groups: artificial saliva, L. brevis suspension, demineralizing agent (DA), and DA plus L. brevis. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) were used to evaluate the surface micromorphology and the mineral content, respectively. The statistical analysis was conducted using a one-way ANOVA, followed by Tukey's post hoc test.

RESULTS

SEM analysis did not highlight significant changes in the enamel microstructure of L. brevis-treated specimens compared to the control. DA-induced damage to the enamel structure was drastically reduced when the specimens were contextually exposed to the probiotic. The treatment with DA substantially reduced the weight % of crucial enamel minerals, i.e., Ca and P. Notably, the probiotic was able to reverse the demineralization process, bringing Ca and P weight % back to basal levels, including the Ca/P ratio.

CONCLUSIONS

The findings indicate that L. brevis is able to efficiently protect the dental enamel surface from the damage caused by DA and increase the enamel resistance to demineralization. Overall, L. brevis confirms its efficacy in preventing or counteracting the action of carious lesions through a novel mechanism that protects the tooth surface under a chemical challenge that mimics the caries process.

Biomineralization and remineralizing potential of toothpastes containing nanosized β-calcium glycerophosphate: an in vitro study

To evaluate the effect of 1100 ppm F toothpastes supplemented with micrometric or nanosized β-CaGP (β-CaGPm/β-CaGPn) on artificial enamel remineralization, using a pH cycling model. Enamel blocks with artificial caries were randomly allocated into ten groups (n = 10), according to the toothpastes: without fluoride/β-CaGPm/β-CaGPn (negative control); 1100 ppm F (1100F); 1100F plus 0.125%, 0.25%, 0.5%, and 1.0% of β-CaGPm or β-CaGPn. The blocks were treated 2×/day with slurries of toothpastes. After pH cycling, the percentage of surface hardness recovery (%SHR); integrated loss of subsurface hardness (ΔKHN); integrated mineral loss (ΔIMR); fluoride (F), calcium (Ca), and phosphorus (P) concentrations in the enamel; polydispersity index (PdI); and zeta potential (Zp) were determined. The data were analyzed by ANOVA (p < 0.001). For Zp/PdI, no significance was observed when comparing the means (p > 0.001). The treatment with 1100F-0.25%β-CaGPn led to %SHR ∼57 higher when compared to the 1100F group (p < 0.001). The lowest ΔKHN was observed for the 1100F-0.25%β-CaGPn group (p < 0.001). The ΔIMR was lower (∼201%) for the 1100F-0.25%β-CaGPn when compared to 1100F (p < 0.001). The association of β-CaGPm and β-CaGPn to 1100F did not influence its F concentration (p > 0.001). The highest increase in Ca and P was observed for 1100F-0.25%β-CaGPn (p < 0.001). The addition of 0.25%β-CaGPn to 1100F toothpaste was able to promote an additional remineralizing effect of artificial caries lesions.

Restorative Dental Resin Functionalized with Calcium Methacrylate with a Hydroxyapatite Remineralization Capacity

The ability of dental materials to induce the mineralization of enamel like hydroxyapatite (HA) is of great importance. In this article, a novel kind of dental restorative material characterized by a mineralization ability was fabricated by photopolymerization. Calcium methacrylate (CMA) was introduced into the classical bisphenol A-glycidyl methacrylate (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA) dental resin formulation. This functional dental resin (BTCM) was calcium-rich and can be prepared simply by one-step photopolymerization. The influence of CMA on the photopolymerization kinetics, the dental resin's mechanical properties, and its capacity to induce dynamic in situ HA mineralization were examined. Real-time FTIR, compression modulus, scanning electron microscopy, X-ray spectroscopy, MTT assay, and cell attachment test were carried out. The obtained data were analyzed for statistical significance using analysis of variance (ANOVA). Double bond conversion could be completed in less than 300 s, while the compression modulus of BTCM decreased with the increase in CMA content (30 wt%, 40 wt%, and 50 wt%). After being soaked in Ca(NO3)2 and Na2HPO4 solutions alternatively, dense HA crystals were found on the surface of the dental resin which contained CMA. The amount of HA increased with the increase in CMA content. The MTT results indicated that BTCM possesses good biocompatibility, while the cell adhesion and proliferation investigation demonstrated that L929 cells can adhere and proliferate well on the surface of BTM. Thus, our approach provides a straightforward, cost-effective, and environmentally friendly solution that has the potential for immediate clinical use.

Peptides in Dentistry: A Scoping Review

Currently, it remains unclear which specific peptides could be appropriate for applications in different fields of dentistry. The aim of this scoping review was to scan the contemporary scientific papers related to the types, uses and applications of peptides in dentistry at the moment. Literature database searches were performed in the following databases: PubMed/MEDLINE, Scopus, Web of Science, Embase, and Scielo. A total of 133 articles involving the use of peptides in dentistry-related applications were included. The studies involved experimental designs in animals, microorganisms, or cells; clinical trials were also identified within this review. Most of the applications of peptides included caries management, implant osseointegration, guided tissue regeneration, vital pulp therapy, antimicrobial activity, enamel remineralization, periodontal therapy, the surface modification of tooth implants, and the modification of other restorative materials such as dental adhesives and denture base resins. The in vitro and in vivo studies included in this review suggested that peptides may have beneficial effects for treating early carious lesions, promoting cell adhesion, enhancing the adhesion strength of dental implants, and in tissue engineering as healthy promotors of the periodontium and antimicrobial agents. The lack of clinical trials should be highlighted, leaving a wide space available for the investigation of peptides in dentistry.

Synergistic remineralization of enamel white spot lesions using mesoporous bioactive glasses loaded with amorphous calcium phosphate

Objectives: The purpose of this study was to create a new delivery system that can synergistically remineralize enamel white spot lesions (WSLs). Materials and methods: The delivery system (PAA-ACP@aMBG) was prepared by using aminated mesoporous bioactive glasses (aMBG) as the carrier loaded with polyacrylic-stabilized amorphous calcium phosphate (PAA-ACP). The materials were characterized by transmission electron microscopy (TEM), X-ray powder diffraction (XRD), inductively coupled plasma-optical emission spectrometry (ICP-OES), and so on. Forty-eight artificial WSLs enamel samples were randomized to four groups: artificial saliva (negative control, NC), casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), PAA-ACP@aMBG, and MBG. The effects of demineralization and remineralization of the enamel surface were compared by means of surface microhardness (SMH) measurements, surface color change measurements, fluorescence microscopy (FM), X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). Results: There was no significant difference in the surface microhardness recovery rate (SMHRR) or color recovery rate (CRR) among the CPP-ACP group, PAA-ACP@aMBG group and MBG group (P>0.05), but these values were significantly higher than those in the NC group (p < 0.01). FM demonstrated that the remineralization depth in the PAA-ACP@aMBG group was significantly greater than that of the remaining three groups (p < 0.01). SEM analysis indicated that the enamel demineralization marks in the PAA-ACP@aMBG group, CPP-ACP group, and MBG group were obscured by mineral deposition. Conclusions: PAA-ACP@aMBG showed good mineralization properties, implying its great potential for clinical application.

Application of fluoride disturbs plaque microecology and promotes remineralization of enamel initial caries

Background

The caries-preventive effect of topical fluoride application has been corroborated by a number of clinical studies. However, the effect of fluoride on oral microecology remains unclear.

Objective

To monitor the effect of fluoride on dental plaque microecology and demineralization/remineralization balance of enamel initial caries.

Methods

Three-year-old children were enrolled and treated with fluoride at baseline and 6 months. International Caries Detection and Assessment System II indices of 52 subjects were measured at baseline, 3, 6, and 12 months. Supragingival plaque samples of 12 subjects were collected at baseline, 3 and 14 days for 16S rRNA sequencing.

Results

Changes in microbial community structure were observed at 3 days after fluoridation. Significant changes in the relative abundance of microorganisms were observed after fluoride application, especially Capnocytophaga, unidentified Prevotellaceae and Rothia. Functional prediction revealed that cell movement, carbohydrate and energy metabolism were affected significantly after fluoride application. Fluoride significantly inhibited enamel demineralization and promoted remineralization of early demineralized caries enamel at 3 months.

Conclusion

Fluoride application significantly inhibited the progression of enamel initial caries and reversed the demineralization process, possibly by disturbing dental plaque microecology and modulating the physicochemical action of demineralization/remineralization. This deepened our understanding of caries-preventive effects and mechanisms of fluoride.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of the 2021 dental literature in restorative dentistry to inform busy dentists regarding noteworthy scientific and clinical progress over the past year. Each member of the committee brings discipline-specific expertise to coverage of this broad topical area. Specific subject areas addressed, in order of the appearance in this report, include COVID-19 and the dental profession (new); prosthodontics; periodontics, alveolar bone, and peri-implant tissues; implant dentistry; dental materials and therapeutics; occlusion and temporomandibular disorders; sleep-related breathing disorders; oral medicine and oral and maxillofacial surgery; and dental caries and cariology. The authors focused their efforts on reporting information likely to influence daily dental treatment decisions with an emphasis on future trends in dentistry. With the tremendous volume of dentistry and related literature being published daily, this review cannot possibly be comprehensive. Rather, its purpose is to update interested readers and provide important resource material for those interested in pursuing greater details on their own. It remains our intent to assist colleagues in negotiating the extensive volume of important information being published annually. It is our hope that readers find this work useful in successfully managing the patients and dental problems they encounter.

Silver nanoparticles associated with a polyphosphate and fluoride enhance the prevention of enamel demineralization and impact on dual-biofilm adhesion

OBJECTIVES

The aim of this study were to produce a multifunctional nanocomposite combining silver nanoaparticles (Ag), sodium trimetaphosphate (TMP) and fluoride (F), to investigate its effect on dental enamel demineralization and on biofilms of Streptococcus mutans and Candida albicans.

METHODS

Bovine enamel blocks were submitted to five pH cycles and treated 2x/day with 100ppm F, 225ppm F, 100ppm F+0.2%TMP or 100ppm F+0.2%TMP+10% Ag (100F/TMP/Ag). Next, surface hardness loss (%SH), integrated loss of subsurface hardness (ΔKHN), enamel fluoride (F) and calcium (Ca) concentration were determined. Biofilms from single and dual species of S. mutans and C. albicans were treated with 100F/TMP/Ag, Ag or chlorhexidine gluconate for 24h. The antibiofilm effect was evaluated by colony-forming unit counting and Scanning Electron Microscopy.

RESULTS

The nanocomposite reduced 43.0% of %SH and was similar with samples treated with 225F, 100F/TMP and 100/TMP/Ag. The attribute of F and/or TMP in reducing ΔKHN in 5-20 μm was not affected by the addiction of Ag (110F = 225F = 100F/TMP = 100F/TMP/Ag > Negative Control). Further, 100F/TMP/Ag strongly reduced viable cells of S. mutans in dual biofilms (∼5 log₁₀cm²) and structurally affected the biofilms.

CONCLUSION

The 100F/TMP/F promoted a protective effect against enamel demineralization and was able to significantly inhibit the growth of biofilms of S. mutans and C. albicans.

CLINICAL SIGNIFICANCE

The focus on prevention and non-invasive dental treatment is the most effective and least costly way to improve the population's oral health conditions. We present a nanocomposite for a multiple approach in prevention of caries.