Recent Advances in Dental Hard Tissue Remineralization: A Review of Literature

Developing a novel glass ionomer cement with enhanced mechanical and chemical properties

OBJECTIVE

To develop a novel glass ionomer cement (NGIC) with enhanced mechanical and chemical properties and assess its biocompatibility, mechanical strength, and ion release.

METHODS

Nanosilver doped bioactive glass (NanoAg BAG) was synthesized by sol-gel method and characterized by scanning electron microscopy with energy-dispersive X-ray spectroscopy and transmission electron microscopy. The NanoAg BAG, together with poly(vinylphosphonic acid) (PVPA), alumino-fluorosilicate glass and poly-acrylic acid were used to synthesize NGIC. The optimal PVPA concentration for NGIC was determined by PVPA modified GIC's biocompatibility and mechanical properties and used to prepare NGIC specimens. NGIC specimens with NanoAg BAG at 0%, 1%, 2%, and 5% were allocated into Groups NGIC0, NGIC1, NGIC2, and NGIC5, respectively. The biocompatibility, surface morphology, elemental composition, surface topography, chemical properties, compressive strength, diametral tensile strength, and ion release of the NGIC were assessed. A conventional glass ionomer cement (GIC) was used as a control.

RESULTS

A granular BAG with nano silver particles attached on its surface were found, indicating the successful synthesis of NanoAg BAG. PVPA at 10% presented the best effect in enhancing the biocompatibility and mechanical properties of PVPA modified GIC and was used to prepare NGIC specimens. NGIC1 showed similar biocompatibility, surface morphology and topography to GIC. Chemical properties results showed that NGICs showed the same adsorption peaks to GIC. The compressive strength (mean±SD in MPa) was 168.1 ± 29.7, 205.5 ± 29.5, 221.8 ± 46.8, 216.6 ± 59.3 and 167.7 ± 36.4, and the diametral tensile strength (mean±SD in MPa) was 14.1 ± 1.7, 18.3 ± 4.9, 21.2 ± 2.2, 17.2 ± 3.8 and 13.3 ± 3.3 for GIC, NGIC0, NGIC1, NGIC2 and NGIC5 respectively. NIGC0, NGIC1 and NGIC2 showed higher compressive and diametral tensile strength than GIC (p < 0.01). NGIC2 and NGIC5 showed higher release of fluoride, calcium, phosphate and silver ion than GIC and NGIC0 (p < 0.05).

CONCLUSION

A biocompatible NGIC with enhanced mechanical properties were developed. It presented enhanced fluoride, calcium, phosphate and silver ion release compared to conventional GIC.

A Comparative Evaluation of Arginine Complex Combined With Flouride and Two Standard Non-Fluoridated Remineralizing Agents: An In Vitro Study

Background Dental caries represents a dynamic process, often reversible in its early stages. Fluoride has conventionally served as the cornerstone for remineralization and early caries arrest. However, excessive fluoride intake can lead to both local and systemic toxicity. Hence, there's a pressing need to develop adjunct therapies that enhance fluoride's efficacy while minimizing its dosage. This study aims to assess and compare the remineralization potential of a novel combination comprising arginine bicarbonate and fluoride against established technologies such as Bioactive glass (NovaMin Technology; Sensodyne Repair and Protect, GlaxoSmithKline, UK) and CPP-ACP technology (GC Tooth Mousse; Tokyo Japan). Materials and methods The experiment utilized extracted premolars designated for orthodontic extraction. The initial evaluation employed the DIAGNOdentTM fluorescence method. Subsequently, teeth underwent demineralization and were measured for values. Following this, the teeth were subjected to seven cycles of remineralization, after which moment values were reassessed. Statistical analysis was performed on the recorded values. Results Participants were divided into six groups (BR-A, AR-A, BR-B, AR-B, BR-C, AR-C). T-tests demonstrated significant reductions in moment values within each group, indicating the effectiveness of all remineralizing agents. Group C exhibited the most substantial difference (-6.900 ± 0.4), followed by Group A and Group B. ANOVA analysis revealed statistically significant differences among all three groups (p=0.016). Tables showed significant distinctions between the remineralizing values of Groups A and C and Groups B and C (p=0.02 and 0.002, respectively), with no discernible distinction between Groups A and B. Conclusion The study elucidates the superior efficacy of the arginine complex with fluoride combination compared to CPP-ACP and Bioactive Glass individually. This finding underscores the potential of the novel combination therapy in enhancing remineralization while minimizing fluoride dosage, thus presenting a promising strategy for addressing early-stage dental caries.

Enamel Matrix Derivative, 58S5 Bioactive Glass, and Fluoride Varnish for Enamel Remineralization: A Multi-analysis Approach

PURPOSE

This study aimed to evaluate the enamel remineralization efficacy of enamel matrix derivative (EMD), experimental bioactive glass (BAG), and fluoride varnish in vitro.

METHODS AND MATERIALS

Artificial initial caries lesions were developed on fifty human enamel specimens using demineralization solution (pH 4.5, 37°C, 96 hours). Specimens were randomly assigned to five groups (n=10): I-5% NaF varnish (Enamelast), II-experimental 58S5 BAG+37% phosphoric acid (PA), III-EMD (Emdogain) + Ethylenediaminetetraacetic Acid (EDTA), IV-EMD+37% PA, V-Control (untreated). All remineralization agents were applied with pH cycling for seven days. The specimens were scanned by spectral domain optical coherence tomography (SD-OCT) at baseline, at demineralization, and after pH cycling. Lesion depths were measured using image analysis software (ImageJ). Lesions were evaluated using surface microhardness (SMH) and two fluorescence methods (FluoreCam and DIAGNOdent Pen [DDPen]). The data were statistically analyzed by Kruskal Wallis, Friedman, and Wilcoxon tests (α=0.05).

RESULTS

According to SD-OCT results, fluoride varnish was found to be the most effective agent in reducing lesion depth (p=0.005). All agents increased the SMH values after pH cycling. No significant difference was found among fluoride varnish, BAG, and EMD+PA groups. These SMH values were significantly higher than EMD+EDTA and control groups (p<0.001). All groups showed lower DDPen scores compared with the control group (p<0.001), however, no significant difference was found among the remineralization agents. In FluoreCam assessment, size and intensity values of all treated groups showed improvement. However, there was no significant difference between the treatment groups in terms of FluoreCam size measurements (p=0.186).

CONCLUSION

58S5 BAG and EMD+PA have remineralization capacity as effective as fluoride varnish. EMD+PA showed better SMH and lesion intensity results than EMD+EDTA.

Dynamics of Dental Enamel Surface Remineralization under the Action of Toothpastes with Substituted Hydroxyapatite and Birch Extract

To address tooth enamel demineralization resulting from factors such as acid erosion, abrasion, and chronic illness treatments, it is important to develop effective daily dental care products promoting enamel preservation and surface remineralization. This study focused on formulating four toothpastes, each containing calcined synthetic hydroxyapatite (HAP) in distinct compositions, each at 4%, along with 1.3% birch extract. Substitution elements were introduced within the HAP structure to enhance enamel remineralization. The efficacy of each toothpaste formulation was evaluated for repairing enamel and for establishing the dynamic of the remineralization. This was performed by using an in vitro assessment of artificially demineralized enamel slices. The structural HAP features explored by XRD and enamel surface quality by AFM revealed notable restorative properties of these toothpastes. Topographic images and the self-assembly of HAP nanoparticles into thin films on enamel surfaces showcased the formulations' effectiveness. Surface roughness was evaluated through statistical analysis using one-way ANOVA followed by post-test Bonferroni's multiple comparison test with a p value < 0.05 significance setting. Remarkably, enamel nanostructure normalization was observed within a short 10-day period of toothpaste treatment. Optimal remineralization for all toothpastes was reached after about 30 days of treatment. These toothpastes containing birch extract also have a dual function of mineralizing enamel while simultaneously promoting enamel health and restoration.

A novel mussel-inspired desensitizer based on radial mesoporous bioactive nanoglass for the treatment of dentin exposure: An in vitro study

OBJECTIVES

The dentin exposure always leads to dentin hypersensitivity and the acid-resistant/abrasion-resistant stability of current therapeutic approaches remain unsatisfatory. Inspired by the excellent self-polymerization/adherence activity of mussels and the superior mineralization ability of bioactive glass, a novel radial mesoporous bioactive nanoglass coated with polydopamine (RMBG@PDA) was developed for prevention and management of dentin hypersensitivity.

METHODS

Radial mesoporous bioactive nanoglass (RMBG) was synthesized by the sol-gel process combined with the cetylpyridine bromide template self-assembly technique. RMBG@PDA was synthesized by a self-polymerization process involving dopamine and RMBG in an alkaline environment. Then, the nanoscale morphology, chemical structure, crystalline phase and Zeta potential of RMBG and RMBG@PDA were characterized. Subsequently, the ion release ability, bioactivity, and cytotoxicity of RMBG and RMBG@PDA in vitro were investigated. Moreover, an in vitro experimental model of dentin hypersensitivity was constructed to evaluate the effectiveness of RMBG@PDA on dentinal tubule occlusion, including resistances against acid and abrasion. Finally, the Young's modulus and nanohardness of acid-etched dentin were also detected after RMBG@PDA treatment.

RESULTS

RMBG@PDA showed a typical nanoscale morphology and noncrystalline structure. The use of RMBG@PDA on the dentin surface could effectively occlude dentinal tubules, reduce dentin permeability and achieve excellent acid- and abrasion-resistant stability. Furthermore, RMBG@PDA with excellent cytocompatibility held the capability to recover the Young's modulus and nanohardness of acid-etched dentin.

CONCLUSION

The application of RMBG@PDA with superior dentin tubule occlusion ability and acid/abrasion-resistant stability can provide a therapeutic strategy for the prevention and the management of dentin hypersensitivity.

Effect of topical applications containing surface pre-reacted glass-ionomer filler on dental hard tissues-A systematic review

OBJECTIVES

The objective of this systematic review was to assess the efficacy of topical applications containing surface pre-reacted glass-ionomer filler on dental hard tissues.

DATA SOURCES

A comprehensive literature search was conducted in PubMed, MEDLINE, Embase, Scopus, ClinicalTrials.gov, Lilacs and Cochrane Central Register of Controlled Trials (until 15.08.2022). Google and Open Grey were used to search for grey literature and handsearching was conducted.

STUDY SELECTION

Clinical and in vitro studies conducted on human adult teeth were considered eligible without date and language restrictions. The electronic database generated 2,488 results. In total, 227 studies were found to be relevant from which 71 duplicates were removed. Title and abstract screening were then conducted, and a total of 33 studies met the inclusion criteria were assessed for full text screening. Two authors concluded that 11 studies satisfied the eligibility criteria. In vitro studies were evaluated using an accepted quality assessment tool for dental studies. Cochrane risk of bias tool was used for quality assessment of clinical randomised studies, whilst ROBINS-I tool was used for non-randomised studies.

RESULTS

Nine in vitro and only two non-randomised clinical trials were reported to meet the eligibility criteria. Results were grouped and analysed separately according to the study design. Different modes of surface pre-reacted glass-ionomer filler delivery were reported in the included studies. Three studies tested the effect of surface pre-reacted glass-ionomer filler containing toothpastes, whilst three studies investigated the effect of polishing pastes with surface pre-reacted glass-ionomer filler, three studies used eluates as surface pre-reacted glass-ionomer filler delivery method and two studies reported the effect of the coatings. The effect of those vehicles was tested on enamel, dentine or oral biofilm. Each study was analysed individually, and heterogeneity was detected among in vitro and clinical studies. Half of the in vitro studies were medium risk, whilst three were low and two studies presented with high risk. In clinical trials, outcome, confounding, selection biases were reported. Meta-analysis was therefore unable to be carried out.

CONCLUSION

Regardless of the mode of delivery and type of studies, all included studies demonstrated the efficacy of surface pre-reacted glass-ionomer filler containing topical applications to inhibit demineralisation of dental hard tissues at a dose dependant manner. Antimicrobial properties towards cariogenic species were also reported.

CLINICAL SIGNIFICANCE

Surface pre-reacted glass-ionomer filler containing topical applications may serve as potential caries preventive and cariostatic tools. The systematic review registered in PROSPERO, International prospective register of systematic reviews, No. CRD42022347130.

Amelogenin-inspired peptide, calcium phosphate solution, fluoride and their synergistic effect on enamel biomimetic remineralization: an in vitro pH-cycling model

BACKGROUND

Several methods were introduced for enamel biomimetic remineralization that utilize a biomimetic analogue to interact and absorb bioavailable calcium and phosphate ions and induce crystal nucleation on demineralized enamel. Amelogenin is the most predominant enamel matrix protein that is involved in enamel biomineralization. It plays a major role in developing the enamel's hierarchical microstructure. Therefore, this study was conducted to evaluate the ability of an amelogenin-inspired peptide to promote the remineralization potential of fluoride and a supersaturated calcium phosphate solution in treating artificially induced enamel carious lesions under pH-cycling regimen.

METHODS

Fifty enamel slices were prepared with a window (4*4 mm2 ) on the surface. Five samples were set as control healthy enamel and 45 samples were subjected to demineralization for 3 days. Another 5 samples were set as control demineralized enamel and 40 enamel samples were assigned into 8 experimental groups (n=5) (P/I, P/II, P/III, P/AS, NP/I, NP/II, NP/III and NP/AS) according to peptide treatment (peptide P or non-peptide NP) and remineralizing solution used (I; calcium phosphate solution, II; calcium phosphate fluoride solution, III; fluoride solution and AS; artificial saliva). Samples were then subjected to demineralization/remineralization cycles for 9 days. Samples in all experimental groups were evaluated using Raman spectroscopy for mineral content recovery percentage, microhardness and nanoindentation as healthy, demineralized enamel and after pH-cycling. Data were statistically analysed using two-way repeated measures Anova followed by Bonferroni-corrected post hoc test for pairwise multiple comparisons between groups. Statistical significance was set at p= 0.05. Additionally, XRD, FESEM and EDXS were used for crystal orientation, surface morphology and elemental analysis after pH-cycling.

RESULTS

Nanocrystals clumped in a directional manner were detected in peptide-treated groups. P/II showed the highest significant mean values in mineral content recovery (63.31%), microhardness (268.81±6.52 VHN), elastic modulus (88.74±2.71 GPa), nanohardness (3.08±0.59 GPa) and the best crystal orientation with I002/I300 (1.87±0.08).

CONCLUSION

Despite pH changes, the tested peptide was capable of remineralizing enamel with ordered crystals. Moreover, the supplementary use of calcium phosphate fluoride solution with peptide granted an enhancement in enamel mechanical properties after remineralization.

Multidisciplinary evaluation of the remineralization potential of three fluoride-based toothpastes on natural white spot lesions

OBJECTIVES

This in vitro study aimed assessing the remineralization potential of three commercial fluoride-based toothpastes in permanent teeth with natural white spot lesions (WSLs). A multidisciplinary approach based on Raman microspectroscopy (RMS), Scanning electron microscopy (SEM), Energy-dispersive x-ray spectroscopy (EDS), and Vickers microhardness (VMH) was exploited.

METHODS

N = 12 human molars with natural WSLs in the proximal-vestibular zone were selected and divided into 4 groups (n = 3) according to the different treatments: HAF (hydroxyapatite with fluoride ions); SMF (sodium monofluorophosphate with arginine); SF (sodium fluoride with enzymes), and CTRL (untreated group). All toothpastes tested contained 1450 ppm of fluoride. Teeth samples were submitted to the following protocol: a 7-day pH cycling treatment, with two daily exposures (2 min each time) to the commercial toothpastes described above. The surface micromorphology (SEM), the chemical/elemental composition (RMS and EDS), and the Vickers microhardness (VMH) were evaluated. Statistical analysis was performed.

RESULTS

A remarkable remineralization of WSLs in SEM images was observed in all treated groups compared to CTRL. In particular, HAF and SF displayed higher values of VMH, phosphates amount (I960), crystallinity (FWHM960), and lower ones of C/P (I1070/I960) with respect to CTRL. Intermediate values were found in SMF, higher than CTRL but lower with respect to HAF and SF. As regards the Ca/P ratio, statistically significant differences (p < 0.05) were found between SF and the other groups.

CONCLUSIONS

All the tested dentifrices have shown to remineralize the WSLs. SF and HAF have comparable capability in hardness recovery and crystallinity; however, SF shows the best remineralizing potential according to both micromorphological and chemical analyses. Clinical relevance The daily use of toothpastes containing hydroxyapatite partially replaced with fluoride, sodium monofluorophosphate with arginine and sodium fluoride toothpaste associated with enzymes represents a preventive, therapeutic, effective, and non-invasive tool for remineralize WSLs.

Dentinomimetics and cementomimetics of Moringa oleifera leaves extract

To evaluate the biomimetic remineralization capabilities of Moringa oleifera leaves (MOL) extract on coronal dentin and acellular cementum, two different concentrations (50 and 200 mg/ml) of MOL extract loaded in plain varnish (M1 and M2 groups respectively) were compared to fluoride varnish (FL group) and native surface (C group). Eighty sound premolar teeth were collected. Forty teeth (10 teeth in each group) were used for coronal dentin testing while the other forty (10 teeth in each group) were used for acellular cementum testing. Teeth in M1, M2, and FL groups were etched for 30 s and then received the specific varnish treatment. All samples were immersed in artificial saliva for 14 days and then collected, dried, and examined by scanning electron microscopy and energy dispersive X-ray spectroscopy (EDX). Histologically, FL group showed mineral deposition as discrete vesicular granules of various sizes on the surface of both coronal dentin and acellular cementum. Mineral deposition only occurred on some DTs openings while opened tubules remained. The surface of the acellular cementum revealed regular grooves, micro-fissures, and cracks. In the M1 and M2 groups, mineral deposition appeared as a homogenous continuous layer on coronal dentin and acellular cementum. Only a few DTs and cementum fissures were not filled completely. In L.S. sections of the coronal one-third, the DTs appeared almost sealed with varying lengths of mineral deposition. EDX results statistical analysis showed that the M2 group had the highest phosphate ions (P-) and calcium ions (Ca+2) at%. MOL has an extraordinary effect on the remineralization of coronal dentin and acellular cementum. It would have a promising ability to control dentinal hypersensitivity and formation of biomimetic cementum tissue.

Novel Remineralizing and Antibiofilm Low-Shrinkage-Stress Nanocomposites to Inhibit Salivary Biofilms and Protect Tooth Structures

Recurrent caries remain a persistent concern, often linked to microleakage and a lack of bioactivity in contemporary dental composites. Our study aims to address this issue by developing a low-shrinkage-stress nanocomposite with antibiofilm and remineralization capabilities, thus countering the progression of recurrent caries. In the present study, we formulated low-shrinkage-stress nanocomposites by combining triethylene glycol divinylbenzyl ether and urethane dimethacrylate, incorporating dimethylaminododecyl methacrylate (DMADDM), along with nanoparticles of calcium fluoride (nCaF2) and nanoparticles of amorphous calcium phosphate (NACP). The biofilm viability, biofilm metabolic activity, lactic acid production, and ion release were evaluated. The novel formulations containing 3% DMADDM exhibited a potent antibiofilm activity, exhibiting a 4-log reduction in the human salivary biofilm CFUs compared to controls (p < 0.001). Additionally, significant reductions were observed in biofilm biomass and lactic acid (p < 0.05). By integrating both 10% NACP and 10% nCaF2 into one formulation, efficient ion release was achieved, yielding concentrations of 3.02 ± 0.21 mmol/L for Ca, 0.5 ± 0.05 mmol/L for P, and 0.37 ± 0.01 mmol/L for F ions. The innovative mixture of DMADDM, NACP, and nCaF2 displayed strong antibiofilm effects on salivary biofilm while concomitantly releasing a significant amount of remineralizing ions. This nanocomposite is a promising dental material with antibiofilm and remineralization capacities, with the potential to reduce polymerization-related microleakage and recurrent caries.

In vitro evaluation of a novel fluoride-coated clear aligner with antibacterial and enamel remineralization abilities

OBJECTIVE

To investigate the antibacterial and enamel remineralization performances as well as physicochemical properties and biocompatibility of a fluoride-coated clear aligner plastic (FCAP).

MATERIALS AND METHODS

FCAP and normal clear aligner plastic (CAP) was bought from the manufacturer (Angelalign Technology Inc, China). The FCAP was observed under scanning electron microscopy. Its element composition, resistance to separation, contact angle, and protein adhesion performance were characterized. Colony-forming unit (CFU) count and 3-(4,5)-dimethylthiazol(-z-y1)-3,5-diphenyltetrazolium bromide (MTT) assay were used to evaluate the antibacterial ability of Streptococcus mutans. Fluoride release-recharge patterns were obtained. Apatite formation was evaluated after immersing FCAP in artificial saliva. Enamel remineralization capability was evaluated in the demineralization model (immersing samples in demineralization solution for 36 h) and pH cycling model (immersing samples in demineralization solution and remineralization solution in turns for 14 days). Cell Counting Kit-8 (CCK-8) and live/dead cell staining kits were used for cytotoxicity assay.

RESULTS

The FCAP showed uniformly distributed fluoride and did not compromise protein adhesion performance. CFU count (5.47 ± 0.55 for CAP, 3.63 ± 0.38 for FCAP) and MTT assay (0.41 ± 0.025 for CAP, 0.28 ± 0.038) indicated that the FCAP had stronger antibacterial activity compared with normal CAP (P < 0.05 for both evaluations). The FCAP could release fluoride continuously for 14 days and could be recharged after immersing in NaF solution. The FCAP could induce the formation of hydroxyapatite in artificial saliva and could reduce the microhardness decrease, color change, and mineral loss of enamels in both two models (P < 0.05 for all evaluations). CCK-8 and live/dead cell staining analyses showed that the coating did not compromise the biocompatibility of the clear aligner (P > 0.05 for CCK-8 evaluation).

CONCLUSIONS

The FCAP had antibacterial, fluoride recharge, and enamel remineralization abilities while it did not compromise physicochemical properties and biocompatibility.

CLINICAL RELEVANCE

The FCAP has the potential to prevent enamel demineralization during clear aligner treatment.

A Systematic Review on the Effect of Strontium-Doped Nanohydroxyapatite in Remineralizing Early Caries Lesion

The aim of this study is to review the potential of strontium-doped nanohydroxyapatite (SrnHAP) as a biomaterial for remineralizing early carious lesions. Publications from 2012 to 2022 were included based on the patient/population, intervention, comparison, and outcomes (PICO) framework, focusing on demineralized enamel treated with strontium-doped nanohydroxyapatite compared to other remineralizing agents, with the primary outcome being remineralization capacity. Electronic databases, namely, PubMed, Cochrane Library, and Google Scholar, were explored from March 31, 2023, to April 10, 2023. Only English language studies were included, while certain research types and studies on bovine teeth were excluded. Bias was assessed using the Cochrane methodology. Five studies were synthesized, all using extracted human maxillary premolars. Four studies focused on remineralizing enamel, while one study focused on remineralizing dentin. Among these studies, comparisons were made between different strontium concentrations and various remineralizing agents such as nanohydroxyapatite (nHAP), Acclaim, casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), and NovaMin. X-ray diffraction analysis was used to examine hydroxyapatite formation, while scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used for characterization. Additionally, one study evaluated the mechanical properties of partially demineralized dentin specimens. This study was registered in the PROSPERO under the ID CRD42023397413 and completed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

A Comparative Study of the Effect of Tooth Mousse Plus Remin Pro and Fluor Protector Gel on Enamel Erosion: An In Vitro Study

Background

The purpose of this in vitro study was to assess the effect of Tooth Mousse Plus, Remin Pro, and Fluor Protector Gel on enamel erosion, measuring mean weight loss after exposure to a demineralizing agent.

Materials and methods

A total of 60 sound-extracted permanent incisors were sectioned and enamel specimens were randomly distributed to different groups. The initial weight of all specimens was registered. The samples were randomly divided into four groups (n = 30). Group I specimens were treated with tap water (control). Groups II, III, and IV were treated with Tooth Mousse, Remin Pro, and Fluor Protector Gel application. After that, specimens were placed all together in a plastic container with 6 mL of a soft drink and immersed for 8 minutes at room temperature, dried, and weighed. Specimens were weighed after each immersion period and mean weight loss was calculated. The data was analyzed for probability distribution using the Kolmogorov-Smirnov test. The intergroup comparison was done using a one-way analysis of variance (ANOVA) followed by post hoc analysis.

Results

According to pairwise comparisons in post hoc analysis, the weight of specimens at baseline was significantly greater than the weight of specimens on day 12. The difference in the mean weight of the specimen from baseline to day 12 was 2.833 mg for group I, 2.367 mg for group II, 1.467 mg for group III, and 2.133 mg for group IV.

Conclusion

Tooth Mousse Plus, Remin Pro, and Fluor Protector Gel have no significant effect on dental erosion.

How to cite this article

Shukla K, Saxena A, Joshi J, et al. A Comparative Study of the Effect of Tooth Mousse Plus Remin Pro and Fluor Protector Gel on Enamel Erosion: An In Vitro Study. Int J Clin Pediatr Dent 2023;16(S-1):S57-S62.

Inorganic Compounds as Remineralizing Fillers in Dental Restorative Materials: Narrative Review

Secondary caries is one of the leading causes of resin-based dental restoration failure. It is initiated at the interface of an existing restoration and the restored tooth surface. It is mainly caused by an imbalance between two processes of mineral loss (demineralization) and mineral gain (remineralization). A plethora of evidence has explored incorporating several bioactive compounds into resin-based materials to prevent bacterial biofilm attachment and the onset of the disease. In this review, the most recent advances in the design of remineralizing compounds and their functionalization to different resin-based materials' formulations were overviewed. Inorganic compounds, such as nano-sized amorphous calcium phosphate (NACP), calcium fluoride (CaF₂), bioactive glass (BAG), hydroxyapatite (HA), fluorapatite (FA), and boron nitride (BN), displayed promising results concerning remineralization, and direct and indirect impact on biofilm growth. The effects of these compounds varied based on these compounds' structure, the incorporated amount or percentage, and the intended clinical application. The remineralizing effects were presented as direct effects, such as an increase in the mineral content of the dental tissue, or indirect effects, such as an increase in the pH around the material. In some of the reported investigations, inorganic remineralizing compounds were combined with other bioactive agents, such as quaternary ammonium compounds (QACs), to maximize the remineralization outcomes and the antibacterial action against the cariogenic biofilms. The reviewed literature was mainly based on laboratory studies, highlighting the need to shift more toward testing the performance of these remineralizing compounds in clinical settings.

What preventive strategies do dentists prescribe for dental caries prevention? - A KAP survey

Background

Dentists play an important role in caries prevention by delivering preventive care, educating patients, and buying related products; it is critical to recognize what they know and believe about caries prevention, as well as how they use caries prevention interventions.

Materials and Methods

A descriptive cross-sectional study was conducted in South India between January 2021 and February 2021 to determine the dentists' knowledge, attitude, and practice of prescribing preventive strategies and remineralizing agents for caries prevention. A questionnaire including 11 self-administered, prestructured questions was made and distributed through electronic media. Chi-square test was done. The test significance value was taken as 0.05.

Results

A total of 252 dental practitioners participated in the study. The majority of general dentists and specialists followed all the measures such as pit and fissure sealants, fluoride application, counseling patients about oral hygiene maintenance, and regular recall after 6 months to 1 year (P > 0.05). Fluoridated remineralization strategy was found to be the most prescribed (69%) strategy for caries prevention. A significant number of dentists think fluoridated mineralization strategies will remain prevalent (P < 0.05). Younger dentists find practicing preventive dentistry more feasible compared to dentists with greater years of experience (P < 0.05).

Conclusion

Dentists across the country are well aware, have sufficient knowledge, and prescribe preventive strategies such as fluoride application, pit and fissure sealants, regular oral health checkups, and counsel the patients about the importance of oral health but there is a lack of implementation of these preventive strategies in everyday practice.

Assessment of the Remineralizing Potential of Biomimetic Materials on Early Artificial Caries Lesions after 28 Days: An In Vitro Study

This study aimed to evaluate the loss of mineral content in the enamel surface in early artificial lesions and to assess the remineralizing potential of different agents by means of SEM coupled with energy-dispersive X-ray analysis (EDX). The analysis was performed on the enamel of 36 molars divided into six equal groups, in which the experimental ones (3-6) were treated using remineralizing agents for a 28-day pH cycling protocol as follows: Group 1, sound enamel; Group 2, artificially demineralized enamel; Group 3, CPP-ACP treatment; Group 4, Zn-hydroxyapatite treatment; Group 5, NaF 5% treatment; and Group 6, F-ACP treatment. Surface morphologies and alterations in Ca/P ratio were evaluated using SEM-EDX and data underwent statistical analysis (p < 0.05). Compared with the sound enamel of Group 1, the SEM images of Group 2 clearly showed loss of integrity, minerals, and interprismatic substances. Groups 3-6 showed a structural reorganization of enamel prisms, interestingly comprising almost the entire enamel surface. Group 2 revealed highly significant differences of Ca/P ratios compared with other groups, while Groups 3-6 showed no differences with Group 1. In conclusion, all tested materials demonstrated a biomimetic ability in remineralizing lesions after 28 days of treatment.

Synchrotron X-ray Studies of the Structural and Functional Hierarchies in Mineralised Human Dental Enamel: A State-of-the-Art Review

Hard dental tissues possess a complex hierarchical structure that is particularly evident in enamel, the most mineralised substance in the human body. Its complex and interlinked organisation at the Ångstrom (crystal lattice), nano-, micro-, and macro-scales is the result of evolutionary optimisation for mechanical and functional performance: hardness and stiffness, fracture toughness, thermal, and chemical resistance. Understanding the physical-chemical-structural relationships at each scale requires the application of appropriately sensitive and resolving probes. Synchrotron X-ray techniques offer the possibility to progress significantly beyond the capabilities of conventional laboratory instruments, i.e., X-ray diffractometers, and electron and atomic force microscopes. The last few decades have witnessed the accumulation of results obtained from X-ray scattering (diffraction), spectroscopy (including polarisation analysis), and imaging (including ptychography and tomography). The current article presents a multi-disciplinary review of nearly 40 years of discoveries and advancements, primarily pertaining to the study of enamel and its demineralisation (caries), but also linked to the investigations of other mineralised tissues such as dentine, bone, etc. The modelling approaches informed by these observations are also overviewed. The strategic aim of the present review was to identify and evaluate prospective avenues for analysing dental tissues and developing treatments and prophylaxis for improved dental health.

Remineralization potential of phosphorylated chitosan and silver diamine fluoride in comparison to sodium fluoride varnish: invitro study

PURPOSE

The purpose of this study was to evaluate and compare the remineralization potential of phosphorylated chitosan nanoparticles (Pchi) and silver diamine fluoride (SDF) compared to sodium fluoride varnish (NaF) on microhardness of artificial carious lesions in a biomimetic minimally invasive approach that is being regarded as the future of preventive dentistry.

METHODS

The sample size included 40 intact extracted maxillary anterior human teeth. Baseline microhardness was recorded using Vickers hardness test and energy-dispersive X-ray spectroscopy (EDX). Artificial caries-like lesions were created on the exposed enamel by suspending all teeth in demineralizing solution for 10 days in a temperature of 37 °C and then the hardness and EDX were remeasured. Samples were then divided into four main groups: Group A (positive control group) n = 10, treated with NaF, Group B n = 10, treated with SDF, Group C n = 10, treated with Pchi and Group D (negative control group) n = 10 that received no treatment. After treatment, samples were incubated in artificial saliva solution at 37 °C in for 10 days and then reassessed. Data were then recorded, tabulated, and statistically analyzed using Kruskal-Wallis test and Wilcoxon signed test. Scanning electron microscope (SEM) was used to analyze the morphological changes of enamel surface after treatment.

RESULTS

Groups B and C showed the highest calcium (Ca) and phosphate (P) content as well as hardness values, while group B had the highest percentage of fluoride. SEM revealed a smooth layer of mineral formed on the surface of enamel for both groups.

CONCLUSION

Pchi and SDF showed the highest increase in enamel microhardness and remineralization potential.

CLINICAL RELEVANCE

The minimally invasive approach for remineralization could be enhanced using SDF and Pchi.

Doctors' Drugs and the Dangers of Dental Decay

Many "anti-something" medications, which are prescribed by medical doctors for older patients, often for dubious reasons, result in a serious reduction in the quantity and quality of saliva. That drug-induced xerostomia can produce dangerous dental decay, particularly in already compromised dentitions.This article suggests that doctors should undertake a personalised "benefits, risks, alternatives, nothing" (BRAN) analysis including an assessment of the possible dental decay risks, especially before prescribing combinations of "anti-" drugs for marginal conditions.Doctors should consider carefully if alternative approaches are feasible which could produce acceptable outcomes without incurring those serious dental decay risks. Alternative approaches may include patients altering their diet and lifestyle to include more physical exercise for controlling conditions such as marginal hypertension, for example, or perhaps prescribing counselling/talking therapies for depression or anxiety.If various "anti-" drugs really do have to be prescribed, this article describes cheap, pragmatic, and effective ways of mitigating the risks of already compromised dentitions developing new decay.

Biomimetic Action of Zinc Hydroxyapatite on Remineralization of Enamel and Dentin: A Review

Biomimetic zinc-carbonate hydroxyapatite technology was developed to realize materials that mimic the natural hydroxyapatite of enamel and dentin and possess good activity in terms of affinity to adhere to these biological tissues. The chemical and physical characteristics of this active ingredient allows the hydroxyapatite itself to be particularly similar to dental hydroxyapatite, enhancing the bond between biomimetic hydroxyapatite and dental hydroxyapatite. The aim of this review is to assess the efficacy of this technology in terms of benefits for enamel and dentin and reduction of dental hypersensitivity.

MATERIALS AND METHODS

A literature search (Pubmed/MEDLINE and Scopus) of articles from 2003 to 2023 was conducted to analyze studies focused on the use of zinc-hydroxyapatite products. Duplicates were eliminated from the 5065 articles found, leaving 2076 articles. Of these, 30 articles were analyzed based on the use of products with zinc-carbonate hydroxyapatite in these studies.

RESULTS

30 articles were included. Most of the studies showed benefits in terms of remineralization and prevention of enamel demineralization in terms of occlusion of the dentinal tubules and reduction of dentinal hypersensitivity.

CONCLUSION

Oral care products such as toothpaste and mouthwash with biomimetic zinc-carbonate hydroxyapatite were shown to provide benefits according to the aims of this review.

Biomineralization-inspired sandwich dentin desensitization strategy based on multifunctional nanocomposite with yolk-shell structure

Dentin hypersensitivity (DH) treatment is far from being unequivocal in providing a superior strategy that combines immediate and long-term efficiency of dentinal tubule (DT) occlusion and clinical applicability. In order to achieve this aim, a type of multifunctional yolk-shell nanocomposite with acid resistance, mechanical resistance and biomineralization properties was developed in this study, which consists of a silica/mesoporous titanium-zirconium nanocarrier (STZ) and poly(allylamine hydrochloride) (PAH)-stabilized amorphous calcium phosphate (ACP) liquid precursor. First, the nanocomposite, named as PSTZ, immediately occluded DTs and demonstrated outstanding acid and mechanical resistance. Second, the PSTZ nanocomposite induced intrafibrillar mineralization of single-layer collagen fibrils and remineralization of demineralized dentin matrix. Finally, PSTZ promoted the odontogenic differentiation of dental pulp stem cells by releasing ACP and silicon ions. The reconstruction of the dentin-mimicking hierarchical structure and the introduction of newly formed minerals in the upper, middle and lower segments of DTs, defined as sandwich-like structures, markedly reduced the permeability and achieved superior long-term sealing effects. The nanocomposite material based on mesoporous yolk-shell carriers and liquid-phase mineralized precursors developed in this study represents a versatile biomimetic sandwich desensitization strategy and offers fresh insight into the clinical management of DH.

Advanced Drug Delivery Platforms for the Treatment of Oral Pathogens

The oral cavity is a complex ecosystem accommodating various microorganisms (e.g., bacteria and fungi). Various factors, such as diet change and poor oral hygiene, can change the composition of oral microbiota, resulting in the dysbiosis of the oral micro-environment and the emergence of pathogenic microorganisms, and consequently, oral infectious diseases. Systemic administration is frequently used for drug delivery in the treatment of diseases and is associated with the problems, such as drug resistance and dysbiosis. To overcome these challenges, oral drug delivery systems (DDS) have received considerable attention. In this literature review, the related articles are identified, and their findings, in terms of current therapeutic challenges and the applications of DDSs, especially nanoscopic DDSs, for the treatment of oral infectious diseases are highlighted. DDSs are also discussed in terms of structures and therapeutic agents (e.g., antibiotics, antifungals, antiviral, and ions) that they deliver. In addition, strategies (e.g., theranostics, hydrogel, microparticle, strips/fibers, and pH-sensitive nanoparticles), which can improve the treatment outcome of these diseases, are highlighted.

Pomegranate Extract Potentiates the Anti-Demineralizing, Anti-Biofilm, and Anti-Inflammatory Actions of Non-Alcoholic Mouthwash When Associated with Sodium-Fluoride Trimetaphosphate

This study investigated the anti-caries and anti-inflammatory effects of mouthwash formulations containing Punica granatum (pomegranate) peel extract (PPE), sodium-trimetaphosphate, and low concentrations of fluoride. PPE was characterized using high-performance liquid chromatography (ellagic acid and punicalagin). Total phenolics were quantified among formulations, and their stability was analyzed for 28 days. The formulation effects were evaluated as follows: (1) inorganic component concentration and reduced demineralization on bovine enamel blocks subjected to pH cycling; (2) anti-biofilm effect on dual-biofilms of Streptococcus mutans ATCC 25175 and Candida albicans ATCC 10231 treated for 1 and 10 min, respectively; and (3) cytotoxicity and production of inflammatory mediators (interleukin-6 and tumor necrosis factor-alpha). The formulation containing 3% PPE, 0.3% sodium-trimetaphosphate, and 225 ppm of fluoride resulted in a 34.5% surface hardness loss; a 13% (treated for 1 min) and 36% (treated for 10 min) biofilm reduction in S. mutans; a 26% (1 min) and 36% (10 min) biofilm reduction in C. albicans; absence of cytotoxicity; and anti-inflammatory activity confirmed by decreased interleukin-6 production in mouse macrophages. Thus, our results provide a promising prospect for the development of an alcohol-free commercial dental product with the health benefits of P. granatum that have been recognized for a millennium.

Remineralization of Artificially Demineralized Human Enamel and Dentin Samples by Zinc-Carbonate Hydroxyapatite Nanocrystals

(1) Background: Decalcified enamel and dentin surfaces can be regenerated with non-fluoride-containing biomimetic systems. This study aimed to investigate the effect of a zinc carbonate-hydroxyapatite-containing dentifrice on artificially demineralized enamel and dentin surfaces. (2) Methods: Human enamel and dentin discs were prepared and subjected to surface demineralization with 30% orthophosphoric acid for 60 s. Subsequently, in the test group (n = 20), the discs were treated three times a day for 3 min with a zinc carbonate-hydroxyapatite-containing toothpaste (biorepair^®). Afterwards, all samples were gently rinsed with PBS (5 s) and stored in artificial saliva until next use. Samples from the control group (n = 20) received no dentifrice-treatment and were stored in artificial saliva, exclusively. After 15 days of daily treatment, specimens were subjected to Raman spectroscopy, energy-dispersive X-ray micro-analysis (EDX), white-light interferometry, and profilometry. (3) Results: Raman spectroscopy and white-light interferometry revealed no significant differences compared to the untreated controls. EDX analysis showed calcium phosphate and silicon dioxide precipitations on treated dentin samples. In addition, treated dentin surfaces showed significant reduced roughness values. (4) Conclusions: Treatment with biorepair^® did not affect enamel surfaces as proposed. Minor mineral precipitation and a reduction in surface roughness were detected among dentin surfaces only.

In Vitro Studies of Graphene for Management of Dental Caries and Periodontal Disease: A Concise Review

Graphene is a single-layer two-dimensional carbon-based nanomaterial. It presents as a thin and strong material that has attracted many researchers’ attention. This study provides a concise review of the potential application of graphene materials in caries and periodontal disease management. Pristine or functionalized graphene and its derivatives exhibit favorable physicochemical, mechanical, and morphological properties applicable to biomedical applications. They can be activated and functionalized with metal and metal nanoparticles, polymers, and other small molecules to exhibit multi-differentiation activities, antimicrobial activities, and biocompatibility. They were investigated in preventive dentistry and regenerative dentistry. Graphene materials such as graphene oxide inhibit cariogenic microbes such as Streptococcus mutans. They also inhibit periodontal pathogens that are responsible for periodontitis and root canal infection. Graphene-fluorine promotes enamel and dentin mineralization. These materials were also broadly studied in regenerative dental research, such as dental hard and soft tissue regeneration, as well as periodontal tissue and bone regeneration. Graphene oxide-based materials, such as graphene oxide-fibroin, were reported as promising in tissue engineering for their biocompatibility, bioactivity, and ability to enhance cell proliferation properties in periodontal ligament stem cells. Laboratory research showed that graphene can be used exclusively or by incorporating it into existing dental materials. The success of laboratory studies can translate the application of graphene into clinical use.

Strategies of Bioceramics, Bioactive Glasses in Endodontics: Future Perspectives of Restorative Dentistry

Prevalently, there is a primary strategy to cure caries using restorative materials notably bioceramics. Existing synthetic materials stimulate natural tooth structure with acceptable interfacial bonding and esthetic and biomechanical qualities with better durability. Several bioceramics have been introduced and investigated for their potentialities as restorative materials. Biomineralization of tooth initiates repair and regeneration of natural dental tissue and reinstating the integrity of periodontium. In the evolution of bioceramics in the aspects of different essential composition for dental application, recent technology and modern strategies revolutionize the restorative dentistry. Bioglass is one among the important bioceramics as a restorative material, and by regulating the properties of the material, it is possible to construct improved formulation towards restoration. This article reviews the current revolution of endodontics, existing restorative materials, and technologies to be achieve for engineering materials with the better design.

Correlation between Two Evaluation Methods for the Effect of Two Desensitizing Materials: An In Vitro Study

AIM: This study was conducted to assess the efficiency of enamel matrix derivative (EMD) on dentin remineralization at two different application times. MATERIALS AND METHODS: Thirty-two human dentin specimens of 1 mm thickness were prepared and randomly divided into two groups according to the treatment material (M) used: fluoride varnish with casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) (M1) and Enamel matrix derivative (EMD) (M2). Following treatment, each group was subdivided into two subgroups (n = 8) based on the storage time in artificial saliva into: (S); subgroup (S1); storage for 15 days and subgroup (S2); storage for 30 days. Dentin permeability was measured for all specimens at baseline and after applying the treatment protocol. All specimens were photomicrographed using ESEM before and after the treatment protocol. RESULTS: The highest permeability reduction percent mean value was recorded for M1S2 specimens (90% ± 20), with a statistically significant difference with other subgroups, followed by subgroup M2S2 (56% ± 8) and subgroup M1S1 (51% ± 11), respectively. Meanwhile, the subgroup M2S1 had the lowest mean value (36% ± 9). In addition, the dentin permeability test was confirmed by the ESEM results. CONCLUSION: EMD could be used as a promising remineralizing agent for dentin remineralization.

Synchrotron radiation analysis of root dentin: the roles of fluoride and calcium ions in hydroxyapatite remineralization

Although the use of fluoride for root caries control is reported to be effective, the mechanism of maintaining hydroxyapatite is still unclear. This study elucidates the roles of fluoride in the recrystallization of hydroxyapatite, and the impact of calcium to maintain the abundance of hydroxyapatite on acid-challenged root dentin with a novel approach - using synchrotron radiation. Root dentin samples obtained from 40 extracted human premolars were subjected to pH challenge in combination with fluoride treatment. The effect of fluoride on hydroxyapatite regeneration on the root was investigated by using a range of fluoride concentrations (1000-5000 p.p.m.) and the EDTA-chelation technique in vitro. Synchrotron radiation X-ray micro-computed tomography and X-ray absorption spectroscopy were utilized to characterize the chemical composition of calcium species on the surface of prepared samples. The percentage of hydroxyapatite and the relative abundance of calcium species were subsequently compared between groups. The absence of calcium or fluoride prevented the complete remineralization of hydroxyapatite on the surface of early root caries. Different concentrations of fluoride exposure did not affect the relative abundance of hydroxyapatite. Sufficient potency of 1000 p.p.m. fluoride solution in promoting hydroxyapatite structural recrystallization on the root was demonstrated. Both calcium and fluoride ions are prerequisites in a caries-prone environment. Orchestration of F^- and Ca²⁺ is required for structural homeostasis of root dentin during acid attack. Sustainable levels of F^- and Ca²⁺ might thus be a strict requirement in the saliva of the population prone to root caries. Fluoride and calcium contribute to structural homeostasis of tooth root, highlighting that routine fluoride use in combination with calcium replenishment is recommended for maintaining dental health. This study also demonstrates that utilization of synchrotron radiation could provide a promising experimental platform for laboratory investigation especially in the dental material research field.

Effect of casein phosphopeptide amorphous calcium fluoride phosphate and calcium glycerophosphate on incisors with molar-incisor hypomineralization: A cross-over, randomized clinical trial

BACKGROUND: Within the scope of minimally invasive dentistry, the use of different biocompatible remineralization agents on incisors affected by molar-incisor hypomineralization (MIH) gains importance. OBJECTIVE: To evaluate the effect of casein phosphopeptide amorphous calcium fluoride phosphate (CPP-ACFP) and calcium glycerophosphate (CaGP) in mineral density (MD) of white/creamy and yellow/brown demarcated opacities on incisors affected by MIH by means laser fluorescence (LF). METHODS: As a cross-over, randomized trial, twenty-two children with 167 incisors affected by MIH were recruited and randomly assigned to one of the two different agents and crossed over to other agents with two weeks washout in between. Incisors were examined by using LF at all before and after three months periods. RESULTS: The results of the paired t-tests for determining the period effect between the baseline findings showed significant difference in white/creamy and yellow/brown demarcated opacities of LF values for both groups (p < 0.05). The difference between both groups according to after categorization of 20% increasing in MD in the percent of change before and after application on LF values; was not found statistically significant in white/creamy (p = 0.970) and yellow/brown (p = 0.948) opacities. CONCLUSIONS: The primary outcome was CPP-ACFP and CaGP had a positive effect in decreasing hypomineralization on MIH-affected enamel for three months period.

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.

Hydroxypropylmethylcellulose as a film and hydrogel carrier for ACP nanoprecursors to deliver biomimetic mineralization

Demineralization of hard tooth tissues leads to dental caries, which cause health problems and economic burdens throughout the world. A biomimetic mineralization strategy is expected to reverse early dental caries. Commercially available anti-carious mineralizing products lead to inconclusive clinical results because they cannot continuously replenish the required calcium and phosphate resources. Herein, we prepared a mineralizing film consisting of hydroxypropylmethylcellulose (HPMC) and polyaspartic acid-stabilized amorphous calcium phosphate (PAsp-ACP) nanoparticles. HPMC which contains multiple hydroxyl groups is a film-forming material that can be desiccated to form a dry film. In a moist environment, this film gradually changes into a gel. HPMC was used as the carrier of PAsp-ACP nanoparticles to deliver biomimetic mineralization. Our results indicated that the hydroxyl and methoxyl groups of HPMC could assist the stability of PAsp-ACP nanoparticles and maintain their biomimetic mineralization activity. The results further demonstrated that the bioinspired mineralizing film induced the early mineralization of demineralized dentin after 24 h with increasing mineralization of the whole demineralized dentin (3-4 µm) after 72-96 h. Furthermore, these results were achieved without any cytotoxicity or mucosa irritation. Therefore, this mineralizing film shows promise for use in preventive dentistry due to its efficient mineralization capability.

Comparison of the effect of fluoride gel and two toothpastes with different materials on remineralization of initial carious lesions in primary teeth

Introduction:

Various types of toothpastes are claimed to be able to improve initial enamel caries. This study compared the effect of fluoride gel and two toothpastes on remineralization of initial caries lesions in primary teeth.

Materials and Methods:

A total of sixty-four sound extracted primary canine were immersed in demineralizing solution at 37°C for 96 h to produce artificial caries in vitro. Enamel pieces (3 × 3 × 5 mm) were prepared from each tooth and mounted in self cure acrylic blocks. The specimens were randomly assigned to four groups (n = 16) based on treatment agent (fluoride gel, Chitodent toothpaste, ReminPro toothpaste, no treatment as control) and underwent a pH cycling model for 10 days. Vickers microhardness (VH) was measured before and after treatment. Data was analyzed using analysis of variance and paired t-test by SPSS 18 (P < 0.05).

Results:

No significant difference was found in VH between groups at baseline (fluoride group: 265.9 ± 44.8, Chitodent group: 282.6 ± 34.6, ReminPro group: 266.5 ± 26.6, control: 272.7 ± 32.5; P = 0.516). Microhardness significantly increased after exposure to ReminPro toothpaste (VH change: 24.1%, P < 0.001) and fluoride gel (VH change: 10.9%, P = 0.046), but no significant changes were observed in Chitodent (VH change: 2.8%, P = 0.635) and control (VH change: - 2.2%, P = 0.181) groups.

Conclusion:

ReminPro toothpaste might be effective in remineralizing initial carious lesions of primary teeth.

Evaluation of Remineralization Seen in Dentin Related to Ceramic Restorations

BACKGROUND

Recently, the caries management had shifted from extension for prevention to early detection and remineralization of remaining tooth structure using noninvasive techniques.

AIM

The present trial was carried out to assess the effect of adding mono-n-Dodecyl phosphate as a surfactant to ceramic on remineralization of dentin.

MATERIALS AND METHODS

The 32 teeth were divided into the following four groups randomly (n = 8 each group) - Group I: cavities not restored, Group II: Restored with ceramic, Group III: restored with ceramic and 2% mono-n-Dodecyl phosphate, and Group IV: restored with ceramic and 5% mono-n-Dodecyl phosphate. Knoop indenter microhardness tests were done at 10, 20, and 40 days. The surface was evaluated under scanning electron microscope. The collected data were subjected to statistical evaluation, and the results were formulated.

RESULTS

In ceramic restored (Group II), an increase in Knoop microhardness (KHN) values was seen at 10-, 20-, and 40-day assessment with the respective values of 102.2 ± 20.3, 118.7 ± 19.4, and 127 ± 15.1. Similarly, a constant increase at different assessments was observed for Groups III and IV with 2% and 5% of mono-n-Dodecyl phosphate with ceramic with a 40-day KHN value of 128.2 ± 21.4 for Group III and 113.5 ± 17.3 for Group IV. A statistically significant difference was seen between ceramic and 5% mono-n-Dodecyl phosphate (Group IV) with hardness values of 30.31%, 29.8%, and 21.78% for Groups II, III, and IV, respectively, at 20 days.

CONCLUSION

The present study concludes that ceramic restorations are effective in promoting dentin remineralization. However, the addition of only 2% mono-n-Dodecyl phosphate was beneficial, whereas 5% mono-n-Dodecyl phosphate reduced the efficacy of ceramic on dentin remineralization.

The Effects of Three Remineralizing Agents on the Microhardness and Chemical Composition of Demineralized Enamel

This study aimed to determine the effects of three different varnish materials (containing casein phosphopeptide-amorphous calcium phosphate, nano-hydroxyapatite, and fluoride) on enamel. Thirty-three extracted human third molars were used for specimen preparation. These were demineralized using phosphoric acid. Three experimental groups (n = 11) were treated with 3M™ Clinpro™ White Varnish, MI Varnish^®, and Megasonex^® toothpaste, respectively, every twenty-four hours for fourteen days. Analysis of the microhardness of the specimens’ enamel surfaces was carried out via the Vickers method, and by scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Analysis was performed at three stages: at baseline value, after demineralization, and after the period of remineralization. Data were subjected to Scheffe’s post hoc test. The mean microhardness values (HV0.1) obtained for the group of samples treated with MI Varnish^® were higher compared with the other two groups (p = 0.001 for both comparisons), while the first and third groups did not differ significantly from each other (p = 0.97). SEM analysis showed uneven patterns and porosities on all samples tested. EDS results showed an increase in the mineral content of the examined samples, with the highest mineral content observed in the MI Varnish^® group. It can be concluded that MI Varnish^® use has a better remineralization effect on enamel than the other two materials.

Assessment of the Potential Ability to Penetrate into the Hard Tissues of the Root of an Experimental Preparation with the Characteristics of a Dental Infiltratant, Enriched with an Antimicrobial Component-Preliminary Study

Infiltration is a method of penetration with a low viscosity resin that penetrates deep into demineralised tooth tissue and fills the intergranular spaces, hence reducing porosity. Carious lesions initially located at the enamel–cement junction are usually found in elderly patients. Those spots are predisposed to bacterial adhesion originating both from biofilm and from gingival pocket bacteria. The aim of this study was to evaluate the penetration of an experimental preparation, which has the characteristics of a dental infiltrant, enriched with an antibacterial component, into the decalcified root cement tissues of extracted human teeth in elderly patients. An experimental preparation with the characteristics of a dental infiltrant was prepared, applied, and polymerised on the surface of extracted, previously decalcified human teeth. The control sample was Icon (DMG, Hamburg, Germany). The ability of the preparations to penetrate deep into the root cement was evaluated using scanning electron and light microscopy. The study showed that an experimental preparation could potentially be used for treatment of early carious lesions within the tooth root in elderly patients, among others, as it penetrates deep into demineralised tissues. More research is needed.

Hydroxyapatite in Oral Care Products-A Review

Calcium phosphate compounds form the inorganic phases of our mineralised tissues such as bone and teeth, playing an important role in hard tissue engineering and regenerative medicine. In dentistry and oral care products, hydroxyapatite (HA) is a stable and biocompatible calcium phosphate with low solubility being used for various applications such as tooth remineralisation, reduction of tooth sensitivity, oral biofilm control, and tooth whitening. Clinical data on these products is limited with varied results; additionally, the effectiveness of these apatite compounds versus fluoride, which has conventionally been used in toothpaste, has not been established. Therefore, this review critically evaluates current research on HA oral care, and discusses the role and mechanism of HA in remineralisation of both enamel and dentine and for suppressing dentine sensitivity. Furthermore, we position HA’s role in biofilm management and highlight the role of HA in dental applications by summarising the recent achievement and providing an overview of commercialised HA dental products. The review also indicates the existing limitations and provides direction for future research and commercialisation of apatite-based oral care products.

Rehardening of Eroded Enamel with CPP-ACFP Paste and CO2 Laser Treatment

BACKGROUND

Diet and lifestyle can destroy tooth structure due to the dissolution of enamel by acidic beverages. The present study evaluated the effect of CO2 laser irradiation and CPP-ACFP (casein phosphopeptide and amorphous calcium phosphate with fluoride) paste on the remineralization of enamel eroded by carbonated soft drinks.

METHODS

In the present in vitro study, 46 human sound premolar teeth were sectioned mesiodistally to achieve 84 samples. Fourteen samples were assigned to the positive control group (G1), and the remaining samples were immersed in 500 mL of cola drink for 2 minutes, followed by rinsing with distilled water for 10 seconds. This procedure was carried out three times to create erosive lesions. Then, the 60 eroded samples were randomly assigned to five groups of G2 to G6 in terms of the treatment as follows: negative control (G2), CO2 laser irradiation (G3), CPP-ACFP paste (G4), CO2 laser irradiation followed by CPP-ACFP paste application (G5), and CPP-ACFP paste application followed by CO2 laser irradiation (G6). The mean surface microhardness of the enamel surface was evaluated and determined at three points for each sample. Data were analyzed with one-way ANOVA and Tukey HSD tests (α = 0.05).

RESULTS

The highest and the lowest hardness values were recorded in the G1 (314 ± 12 kg/mm2) and G2 (213.7 ± 12 kg/mm2) groups, respectively. ANOVA revealed significant differences between the study groups (P < 0.001). Two-by-two comparisons showed significant differences between the G2 group and the other groups, indicating the efficacy of all the treatment modalities in tooth remineralization and rehardening procedures (P < 0.05). Only in group G6, the enamel microhardness was not significantly different from the G1 positive control group (P > 0.05).

CONCLUSION

Considering the parameters used in the present study, CO2 laser irradiation or CPP-ACFP paste application alone increased eroded enamel's surface hardness; however, their sequential application was more effective in rehardening the eroded enamel's surface to near-normal levels.

Role of bioglass in enamel remineralization: Existing strategies and future prospects-A narrative review

Enamel, once formed, loses the ability to regenerate due to the loss of the formative ameloblasts. It is subjected to constant damaging events due to exposure to external agents and oral microbiomes. An enamel remineralization process targets to replenish the lost ionic component of the enamel through a multitude of methods. Enamel remineralization is highly challenging as it has a complex organized hierarchical microstructure. Hydroxyapatite nanocrystals of the enamel vary in size and orientation along alignment planes inside the enamel rod. The inability of the enamel to remodel unlike other mineralized tissues is another substantial deterrent. One of the well-known biomaterials, bioglass (BG) induces apatite formation on the external surface of the enamel in the presence of saliva or other physiological fluids. Calcium, sodium, phosphate, and silicate ions in BG become responsive in the presence of body fluids, leading to the precipitation of calcium phosphate. Studies have also demonstrated the bactericidal potential of BG against Streptococcus mutans biofilms. The anticariogenicity and antibacterial activity were found to be enhanced when BG was doped with inorganic ions such as F, Ag, Mg, Sr, and Zn. Due to the versatility of BG, it has been combined with a variety of agents such as chitosan, triclosan, and amelogenin to biomimic remineralization process. Key strategies that can aid in the development of contemporary enamel remineralization agents are also included in this review.

[Application of biomimetic restoration in oral-maxillofacial hard tissue repair]

Oral-maxillofacial hard tissue is the support of maxillofacial structure and appearance, and lays the foundation for functions of oral and maxillofacial system. Once the defect occurs, it will not only affect the physiological functions such as chewing and pronunciation, but also have a significant impact on the psychological and social life of patients. However, the self-repairing capability of the oral-maxillofacial hard tissue is pretty limited, in which case, substitute materials are required for tissue repair. A huge gap exists between the physical, chemical, structural characteristics of conventional substitute materials and those of human hard tissues, resulting in poor repair effect. Based on this, scholars simulated the process of biomineralization in the development of hard tissues, to improve the structure and function of materials through biomimetic mineralization technology and enhance the repair performance of materials. The current understanding of biomineralization theory and the construction of biomimetic repair technology is still in the stage of rapid development. In recent years, a mass of innovative studies are keeping emerging. In this review, the representative advances in the repair of oral-maxillofacial hard tissues of the past five years are reviewed.

Drug Delivery (Nano)Platforms for Oral and Dental Applications: Tissue Regeneration, Infection Control, and Cancer Management

The oral cavity and oropharynx are complex environments that are susceptible to physical, chemical, and microbiological insults. They are also common sites for pathological and cancerous changes. The effectiveness of conventional locally-administered medications against diseases affecting these oral milieus may be compromised by constant salivary flow. For systemically-administered medications, drug resistance and adverse side-effects are issues that need to be resolved. New strategies for drug delivery have been investigated over the last decade to overcome these obstacles. Synthesis of nanoparticle-containing agents that promote healing represents a quantum leap in ensuring safe, efficient drug delivery to the affected tissues. Micro/nanoencapsulants with unique structures and properties function as more favorable drug-release platforms than conventional treatment approaches. The present review provides an overview of newly-developed nanocarriers and discusses their potential applications and limitations in various fields of dentistry and oral medicine.

Comparative evaluation of qualitative and quantitative remineralization potential of four different remineralizing agents in enamel using energy-dispersive X-ray: An in vitro study

Background:

The principles of minimally invasive dentistry clearly tells us the need for clinically effective measures to remineralize the early enamel caries lesions.

Aims and Objectives:

The aim of this study was to evaluate the remineralisation potential of four different remineralisation agents used quantitatively by surface microhardness and qualitatively by energy dispersive X ray analysis.

Materials and Methods:

Artificial enamel lesions were created on the buccal surfaces of 60 extracted mandibular second premolar. Specimens were randomly assigned to four groups (n=15) according to the remineralisation agents used: Group 1-Nano Hydroxyapatite, Group 2-Fluoride, Group 3-CPP ACP, Group 4-Chitosan 5mg. All products were applied according to the manufacturer's instructions and specimens were stored in daily renewed artificial saliva. Surface microhardness was assessed using Rockwell hardness test and change in mineral content was evaluated using Energy Dispersive X ray analysis.

Statistical Analysis:

One way analysis of Variance test and post-hoc Tukey test were conducted for multiple group comparison.

Results:

There was remarkable remineralisation in Hydroxyapatite treated comparatively to the other three groups.

Conclusion:

All remineralising agents showed improved surface remineralisation. However complete remineralisation did not occur within 7 days. Nanohydroxyapatite showed the highest potential for remineralisation followed by CPP-ACP, Chitosan and Fluoride.

Comparative Remineralization Efficacy of Topical NovaMin and Fluoride on Incipient Enamel Lesions in Primary Teeth: Scanning Electron Microscope and Vickers Microhardness Evaluation

OBJECTIVE

 Evaluating the potential remineralization effect of NovaMin prophylaxis paste on artificial enamel lesions in primary teeth using Vickers microhardness and scanning electron microscope.

MATERIALS AND METHODS

 Forty sound buccal and lingual surfaces of human primary canine teeth were randomly divided into two groups after creating artificially demineralized lesions (G1: NovaMin and G2: fluoride; 20 per group) and then treated with the respective remineralization agents. The remineralization cycle repeated twice daily for 10 days. The groups were evaluated with Vickers microhardness and scanning electron microscope before and after de/remineralization.

RESULTS

 Statistically significant difference of microhardness was observed between demineralized enamel and remineralized enamel with group 1 and group 2 (p = 0.000 and p = 0.000, respectively). No statistically significant difference of microhardness was observed between two remineralized agents (p = 0.368).

CONCLUSION

 Within the limitation of this in vitro study, NovaMin enhances the remineralization process equally to fluoride.

Advances of Anti-Caries Nanomaterials

Caries is the most common and extensive oral chronic disease. Due to the lack of anti-caries properties, traditional caries filling materials can easily cause secondary caries and lead to treatment failure. Nanomaterials can interfere with the bacteria metabolism, inhibit the formation of biofilm, reduce demineralization, and promote remineralization, which is expected to be an effective strategy for caries management. The nanotechnology in anti-caries materials, especially nano-adhesive and nano-composite resin, has developed fast in recent years. In this review, the antibacterial nanomaterials, remineralization nanomaterials, and nano-drug delivery systems are reviewed. We are aimed to provide a theoretical basis for the future development of anti-caries nanomaterials.

Effect of divalent ions on cariogenic biofilm formation

Background

Divalent cations are able to interact with exopolysaccharides (EPS) and thus are capable to modify the structure and composition of dental biofilm. At the moment, little is known about the adsorption of metals by cariogenic EPS; thus, the aim of the present study was to evaluate the effect of divalent ions (calcium, magnesium, and zinc) on the growth and biofilm formation of mutans streptococci and on the dissolution of hydroxyapatite as well as to investigate their binding to the bacterial EPS.

Results

S. mutans strains used in this study show the highest tolerance towards calcium of the ions tested. Growth parameters showed no differences to control condition for both strains up to 100 mM; revealing natural tolerance to higher concentration of calcium in the surroundings. Although excessive levels of calcium did not impair the growth parameters, it also did not have a positive effect on biofilm formation or its binding affinity to EPS. Magnesium-saturated environment proved to be counterproductive as strains were able to dissolve more Ca²⁺ from the tooth surface in the presence of magnesium, therefore releasing excessive amounts of Ca²⁺ in the environment and leading to the progression of the disease. Thus, this supports the idea of self-regulation, when more Ca²⁺ is released, more calcium is bound to the biofilm strengthening its structure and however, also less is left for remineralization. Zinc inhibited bacterial adhesion already at low concentrations and had a strong antibacterial effect on the strains as well as on calcium dissolution; leading to less biofilm and less EPS. Additionally, Zn²⁺ had almost always the lowest affinity to all EPS; thus, the unbound zinc could also still remain in the surrounding environment and keep its antimicrobial properties.

Conclusion

It is important to maintain a stable relationship between calcium, magnesium and zinc as excessive concentrations of one can easily destroy the balance between the three in cariogenic environment and lead to progression of the disease.

Diagnostic accuracy of 870-nm spectral-domain OCT with enhanced depth imaging for the detection of caries beneath ceramics

OBJECTIVES

To evaluate the diagnostic accuracy of optical coherence tomography (OCT) for the non-invasive detection of caries adjacent to ceramic materials.

METHODS

Disks made from five ceramic materials (hybrid ceramic, feldspathic ceramic, zirconia-reinforced lithium silicate, lithium disilicate, and high-translucent zirconia) were ground to the recommended material thickness for single crown restorations and laminated with a 100 μm thick layer of one of three adhesive cements. The disks were fixed to extracted human molars with or without carious lesions of one of three standardized sizes. A total of 240 stacks of cross-sectional scans obtained using an 870-nm SD-OCT with enhanced depth imaging (EDI) were presented to five raters. Diagnostic accuracy was determined by rating the teeth beneath the cemented material as carious or healthy.

RESULTS

Carious samples were distinguished from sound teeth with high diagnostic accuracy, even for early stage caries. Sensitivity (SE) and specificity (SP) pooled over all raters and all materials were 0.9 and 0.97, respectively. When analyzing the effect of the ceramic and cement materials on detection rates, high SE and SP values of >0.96 and >0.91, respectively, were recorded for lithium disilicate, zirconia-reinforced lithium silicate, and high-translucent zirconia irrespective of the cement type. For hybrid and feldspathic ceramics, the cement material was found to have a significant effect on caries detection.

CONCLUSIONS

Given its high diagnostic accuracy, 870-nm SD-OCT with EDI might be useful for the detection of caries beneath restorative materials. The effect of the prescribed ceramic and cement material on optical penetration depth is substantial.

Prevalence and incidence of dental caries associated with the effect of tooth brushing and fluoride varnishing in schoolchildren at Galapagos Islands, Ecuador: Protocol of the EESO-Gal study

Introduction

Dental caries is the most prevalent oral disease in Ecuador. In our country, there are no studies that have included the population of the Galapagos Islands. Fluoride application to incipient lesions of dental caries has shown to be effective in avoiding the use of invasive restorative procedures.

Objectives

The objective of the EESO-Gal study is to determine the prevalence and incidence of dental caries and to evaluate the effect of supervised dental brushing, accompanied by periodic applications of fluoride varnish on incipient precarious lesions of schoolchildren in the Galapagos Islands. This article presents the protocol of the EESO-Gal study.

Methods

A cohort is planned with Galapagos Islands schoolchildren to determine the prevalence and incidence of dental caries, with assessments every six months, during twenty-four months.

Results

We expect to determine the prevalence and incidence of caries every six months, for twenty-four months, in schoolchildren between three and ten years of age, and obtain data to show the state of the caries conditions in Galapagos schoolchildren, with the inclusion of daily brushing at school, supervised by the teacher, and with the application of fluoride varnish every six months.

Conclusions

The prevalence of dental caries and incidence after the program will demonstrate the importance of implementing oral health prevention and promotion actions to create hygiene and health habits from an early age.