Prevention Of Secondary Caries Research Articles

Prevention of secondary caries using fluoride-loaded chitosan nanoparticle-modified glass-ionomer cement.

To study the effect of incorporating chitosan and fluoride-loaded chitosan nanoparticles into a glass-ionomer cement (GIC) to prevent secondary caries. A standard cervical cavity (mesio-distal width 6mm, cervico-occlusal width 2mm, and depth 2mm) was prepared on 30 molars for the following restoration groups: group 1, conventional GIC restoration; group 2, chitosan (10%) modified GIC restoration; group 3, fluoride loaded chitosan nanoparticles (10%) modified GIC restoration. The restored teeth were subjected to 1,500 thermal cycles before undergoing a multi-species cariogenic biofilm challenge. The restored teeth were examined by micro-computed tomography (micro-CT), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX). Data were analyzed by the one-way ANOVA, Tukey HDS, Kruskal Wallis, and Dunn's test. Micro-CT determined outer lesion depths for groups 1-3 were: 614 ± 20μm, 589 ± 17μm, and 560 ± 19μm respectively. Both modifications with chitosan and fluoride-loaded chitosan nanoparticles significantly affected outer lesion depth (p < 0.05). The modification with fluoride-loaded chitosan nanoparticles statistically significantly decreased the outer lesion depth compared to all other groups (p < 0.05). SEM/EDX showed an increase of calcium, phosphorus, and fluoride at the root dentine adjacent to the restoration in groups 2 and 3 (modified GIC). This increase was statistically significantly higher in the group modified with fluorine-loaded nano chitosan particles compared to the other groups (p < 0.05). Incorporation of 10% chitosan and 10% fluoride-loaded chitosan nanoparticles into GIC restorative material can prevent secondary root caries development. 10% fluoride-loaded chitosan nanoparticles were more effective. Glass ionomer cement modified with fluoride-loaded chitosan nanoparticles may be a promising restorative material in pediatric and preventive dentistry due to their controlled release properties.

Preparation and antibacterial evaluation of silver-doped zirconia for enhanced dental restoration performance

Because of its superior strength, esthetic properties, and excellent biocompatibility, zirconia is preferred for dental prosthetic such as crowns and bridges. However, zirconia crowns and bridges are susceptible to secondary caries owing to margin leakage. Silver is a well-known antibacterial agent, making it a desirable additive to zirconia crowns and bridges for secondary caries prevention. This study focuses on imparting zirconia composite with antibacterial properties to enhance its protective capacity in dental restorations. We used the sol-gel method to dope Ag into zirconia. Silver-doped zirconia powders were prepared at Zr:Ag molar ratios of 100:0,100:0.1, 100:0.5, 100:1, 100:3, and 100:5 (respective samples denoted as Ag-0, Ag-0.1, Ag-0.5, Ag-1, Ag-3, and Ag-5) and were subjected to firing at various temperatures (400 °C-1000 °C). We performed x-ray diffraction to investigate the crystal phase of these powders and x-ray fluorescence and field emission scanning electron microscopy to analyze their elemental composition and surface morphology, respectively. Moreover, we performed spectrophotometry to determine theL*a*b* color values, conducted dissolution tests, and quantified the Ag content through inductively coupled plasma optical emission spectroscopy. In addition, we studied the antibacterial activity of the samples. Analyses of the samples fired at ⩽600 °C revealed a predominantly white to grayish-white coloration and a tetragonal crystal phase. Firing at ⩾700 °C resulted in gray or dark gray coloration and a monoclinic crystal phase. The Ag content decreased after firing at 900 °C or 1000 °C. Ag-0.5 and above exhibited antibacterial activity against bothEscherichia coliandStaphylococcus aureus. Therefore, the minimum effective silver-doped zirconia sample was found to be Ag-0.5. This study allows the exploration of the antimicrobial potential of silver-doped zirconia materials in dental applications such as prosthdontical lining materials, promoting the development of innovative restorations with protective capacity against secondary caries.

Hydrated Calcium Silicate in Resin Composites for Prevention of Secondary Caries

Introduction and aimsThe gaps at the margins of restorative composite resin can increase as the carious process occurs underneath the materials, causing further demineralization along the tooth cavity wall. The aim of this study was to evaluate the effects of restorative resin composite containing hydrated calcium silicate (hCS) filler on enamel protection against demineralization by simulating microleakage between the test material and teeth in a cariogenic environment. MethodsThe experimental resin composites were composed of 70 wt.% filler, which was mixed with a glass filler and hCS in a weight ratio of 70.0% glass (hCS 0), 17.5% hCS + 52.5% glass (hCS 17.5), 35.0% hCS + 35.0% glass (hCS 35.0), and 52.5% hCS + 17.5% glass (hCS 52.5). A light-cured experimental resin composite disk was positioned over a polished bovine enamel disk, separated by a 30-µm gap, and immersed in artificial saliva with pH 4.0 for 15, 30, and 60 days. After the immersion period, the enamel disk was separated from the resin composite disk and evaluated using a microhardness tester, atomic force microscopy, and polarized light microscopy. The opposing sides of the enamel and resin composite disks were observed using scanning electron microscopy/energy dispersive X-ray spectrometry. ResultsThe enamel surface showed a significant increase in microhardness, decreased roughness, and remineralization layer as the proportion of hCS increased (P < .05). In the scanning electron microscopy image, the enamel surface with hCS 35.0 and 52.5 after all experimental immersion periods, showed a pattern similar to that of a sound tooth. ConclusionsThe results demonstrated that increasing the hCS filler level of restorative resin composites significantly decreased enamel demineralization. Clinical relevanceHydrated calcium silicate laced restorative resin composites may be a promising dental biomaterial for protecting teeth against demineralization and preventing secondary caries around restorations.

Effective prevention of secondary caries in children’s permanent teeth using oral hygiene products

Relevance. In Russia, caries prevalence rate in permanent teeth of 12- year-olds is 75, 6%, and in 15-year-olds, it is 87, 5%. Alongside with high prevalence of caries in permanent children’s teeth, the problem of secondary caries is very significant as well. Toothpastes containing fluoride use for caries prevention. Now, there are known toothpastes containing hydroxyapatite enriched with complex (PGC) with amino acid threonine. It is advisable to study this paste effect on secondary caries occurrence.Materials and methods. Clinical and laboratory examinations and treatment of 92 children, aged 7 to 15, aged (97 teeth) were carried out during one year. They were given dental treatment, including that of dentine caries, in permanent teeth (K02.1). Fillings marginal integrity was assessed using G. Ryge (1998) criterion and electrometry method. Carious process intensity in study groups was determined using indices DMFS and ICDAS-II (code I, code II).Results. In group using toothpaste containing hydroxyapatite enriched with complex (PGC) with amino acid threonine, frequency of unsatisfactory restorations was detected only in 6% of cases; in group using fluoride containing pastes – 12%. Electrical conductivity of hard tissues in these groups increased only by 9,6 % and 36% respectively. Frequency of restorations with secondary caries signs at the end of the study was 27% in group with no preventive measures, and according to electrometric method, electrical conductivity at the border of fillings with hard dental tissues increased by 130%. Reduction of caries growth in group using toothpaste containing hydroxyapatite was 78,6%, in group with fluoride containing toothpaste – 64,3%.Conclusion. Application of a toothpaste containing hydroxyapatite enriched with Polyol Germanium Complex with amino acid threonine increases efficiency of secondary caries prevention in children's permanent teeth.

Inhibition of the Biofilm Formation of Anaerobic Bacteria Involved in Secondary Caries by Dental Adhesive

Secondary caries is a type of carious lesion found at the margins of or next to an existing restoration after the filling has been used for a period of time. It generally arises from the formation of defects or cracks in the filling material after restoration. This can create gaps between the material and the tooth tissue, which will allow bacteria in the biofilm to enter the interface. Dental adhesives are commonly used to provide retention for composite cement or filling materials. A good adhesive should be able to prevent leakage along the restoration margin as well as resist the mechanical load of chewing pressure. Recently, the inclusion of calcium in the adhesive monomer has been produced as Bio-Coat Ca, and its antimicrobial property against some oral bacteria has been studied. No information was found on anaerobes. The aim of this study was to evaluate the antimicrobial potential of dental adhesive on the biofilm formation of anaerobic bacteria involved in secondary caries. An adhesive containing CMET (calcium salt of 4-methacryloxyethyl trimellitic acid) and 10-methacryloyloxydecyl dihydrogen calcium phosphate (MDCP) (Bio-Coat Ca, Sun Medical, Moriyama, Shiga, Japan) was applied to the flat-bottom surface of the saliva-coated 96-well plate. Then it was polymerized with LED light at 460 nm and sterile with UV light. Porphyromonas gingivalis ATCC 33277, Prevotella intermedia ATCC 25611, and Fusobacterium nucleatum ATCC 25586 were prepared as a suspension of approximately 1 × 108 CFU/mL and added to the well. The plate was left for 120 min at 37°C in a shaking incubator (120 r/min) to allow bacterial adhesion. After removing non-adherent cells, Schaedler broth was added and further incubated for 48-72 h to grow the biofilm. The culture medium was changed every 24 h. A biofilm formed on a 96-well plate surface without the adhesive was set up as a control. The amount of vital biofilm was assessed by the WST Microbial Cell Counting Kit (Dojindo Molecular Technologies, USA). All tests were triplicated performed and repeated three times. As a statistical analysis, the Mann-Whitney U test was applied. The results showed that dental adhesive exhibited significant anti-biofilm formation of P. gingivalis and F. nucleatum at a percent inhibition of 56% and 46%, respectively. On the other hand, no significant effect was found on P. intermedia. This was similar to our previous report on bacteria associated with primary caries, which revealed that the anti-biofilm effect of Bio-Coat Ca adhesive on Streptococcus mutans was 65% while no significant suppressive action was observed Lactobacillus casei and Actinomyces viscosus. The inhibitory effect of the adhesive was proposed to be the acidic characteristic of the monomers. This newly developed adhesive could be a promising material for the prevention of secondary caries. However, this study was done on the single-species biofilm formation in vitro and conducted in a short time. Long-term clinical studies are needed to evaluate the effect on the patients.

Antibacterial Efficacy and Mechanical Strength of Direct Dental Composite Resins with Integrated Metal and Metal Oxide Nanoparticles: A Systematic Review of In-Vitro Studies

The present systematic review aimed to evaluate the antibacterial efficacy and mechanical strength of direct dental composite resins with integrated metal/metal oxide nanoparticles (NPs). A review was performed using different electronic databases employing MeSH terms for identifying relevant published literature, without any restrictions on language and date of publication. The antibacterial activity of metal/metal oxide NPs-incorporated composites for the prevention of secondary caries was the primary outcome, whereas the mechanical strength was designated as the secondary outcome. 6 studies used varying amounts of silver (AgNPs); 5 studies used zinc oxide (ZnO-NPs); 1 study used Ag-doped ZnO-NPs. Four studies found a statistically significant (p &lt; 0.05) antibacterial activity of varying amounts of ZnO-NPs, five studies found a statistically significant (p &lt; 0.05) antibacterial activity of AgNPs, two studies reported a statistically non-significant (p &gt; 0.05), however greater antibacterial activity, by the incorporation of AgNPs. All included studies reported that the mechanical strength of the composites was not compromised by the addition of either ZnO-NPs or AgNPs. Metal/metal oxide-modified direct dental composite resins resulted in improved antibacterial efficacy without compromising their mechanical strength as compared to non-modified composite resins. However, it is imperative to determine an equilibrium between the mechanical features and antibacterial activity of these materials, and more in vivo investigations are recommended in this aspect.

Developing Bioactive Dental Resins for Restorative Dentistry.

Despite its reputation as the most widely used restorative dental material currently, resin-based materials have acknowledged shortcomings. As most systematic survival studies of resin composites and dental adhesives indicate, secondary caries is the foremost reason for resin-based restoration failure and life span reduction. In subjects with high caries risk, the microbial community dominated by acidogenic and acid-tolerant bacteria triggers acid-induced deterioration of the bonding interface and/or bulk material and mineral loss around the restorations. In addition, resin-based materials undergo biodegradation in the oral cavity. As a result, the past decades have seen exponential growth in developing restorative dental materials for antimicrobial applications addressing secondary caries prevention and progression. Currently, the main challenge of bioactive resin development is the identification of efficient and safe anticaries agents that are detrimental free to final material properties and show satisfactory long-term performance and favorable clinical translation. This review centers on the continuous efforts to formulate novel bioactive resins employing 1 or multiple agents to enhance the antibiofilm efficacy or achieve multiple functionalities, such as remineralization and antimicrobial activity antidegradation. We present a comprehensive synthesis of the constraints and challenges encountered in the formulation process, the clinical performance-related prerequisites, the materials' intended applicability, and the current advancements in clinical implementation. Moreover, we identify crucial vulnerabilities that arise during the development of dental materials, including particle aggregation, alterations in color, susceptibility to hydrolysis, and loss of physicomechanical core properties of the targeted materials.

Three-Dimensional Assessment of Radiographic Changes after Indirect Pulp Capping Using Silver Diamine Fluoride with or without Potassium Iodide in Young Permanent Teeth (12-Month RCT)

The aim of this study was to conduct a three-dimensional (3D) evaluation of radiographic changes after indirect pulp capping (IPC) with silver diamine fluoride (SDF) with or without potassium iodide (KI) and resin-modified glass ionomer cement (RMGIC) in deep carious young permanent molars using cone-beam computed tomography (CBCT). 108 first permanent molars with deep occlusal cavitated caries lesions, in forty-nine 6- to 9-year-old children, were randomly allocated to one of 3 groups (n = 36) and treated with SDF+KI, SDF, and RMGIC as IPC materials. CBCT scans were taken at 0 and 12 months to assess tertiary dentin formation (volume and grey level intensity), increase in root length, and pathological changes such as secondary caries, periapical radiolucency, internal resorption, and obliteration of the pulp. The 3D image analysis procedures were performed using ITK-SNAP and 3D Slicer CMF. Comparisons were made using analysis of variance with a fixed effect for treatment and random effects for patient and patient-by-treatment to account for within-patient correlations. A two-sided 5% significance level was used. There were no significant differences among the three groups regarding tertiary dentin volume (p = 0.712) and grey level intensity (p = 0.660), increase in root length (p = 0.365), prevention of secondary caries (p = 0.63), and periapical radiolucency (p = 0.80) in the analysed 69 CBCT scans. The study did not find differences among the groups regarding quality and quantity of tertiary dentin formed, increase in root length, absence of secondary caries, and other signs of failure as shown by CBCT. Clinical Significance: The results show no significant differences in radiographic outcomes (quality and quantity of tertiary dentin formed, increase in root length, absence of secondary caries, and other signs of failure) when using SDF+KI, SDF, and RMGIC in IPC. The results of this study can help guide treatment decision-making regarding use of SDF and SDF+KI as IPC materials in deep cavitated lesions.

Effect of Zinc Oxide Incorporation on the Antibacterial, Physicochemical, and Mechanical Properties of Pit and Fissure Sealants.

This study aimed to evaluate the antibacterial, physicochemical, and mechanical properties of pit and fissure sealants containing different weight percentages of zinc oxide nanoparticles (ZnO NPs). The following amounts of ZnO NPs were added to a commercially available pit and fissure sealant (BeautiSealant, Shofu, Japan) to prepare the experimental materials: 0 wt.% (commercial control (CC)), 0.5 wt.% (ZnO 0.5), 1 wt.% (ZnO 1.0), 2 wt.% (ZnO 2.0), and 4 wt.% (ZnO 4.0). The antibacterial effect against S. mutans was confirmed by counting the colony-forming units (CFUs) and observing live/dead bacteria. In addition, ion release, depth of cure, water sorption and solubility, and flexural strength tests were conducted. When compared with the CC, the experimental groups containing ZnO NPs showed zinc ion emission and significantly different CFUs (p < 0.05) with fewer live bacteria. ZnO NP addition reduced the depth of cure and water solubility and increased water sorption in comparison with the CC (p < 0.05). However, all groups showed similar flexural strength (p > 0.05). The pit and fissure sealants containing ZnO NPs exhibited antibacterial activity against S. mutans with no negative effects on physicochemical and mechanical properties, and thus, these sealants can be ideal secondary caries prevention material.

Sodium aluminum silicate composite ceramics with secondary caries prevention for dental crown restoration

Secondary caries caused by plaque accumulation at the edge of crown restorations is still a significant reason for crown restoration treatment failures. To prevent secondary caries, it is urgent to develop dental crown restorative materials with good antibacterial ability and mechanically stable properties. In this work, functionalized dental crown restorations were successfully prepared by doping the human trace element Zn into sodium aluminum silicate ceramics (NAS/Zn). The results demonstrated that the NAS/Zn composite ceramics killed Streptococcus mutans (S. mutans) effectively. The Zn ions released by NAS/Zn composite ceramics disrupted the bacterial membrane integrity and DNA proliferation, promoted the outflow of protein, and eventually led to bacterial death. Most notably, NAS/Zn composite ceramics exhibited excellent biocompatibility. This study will provide a new strategy to prevent the occurrence of secondary caries via the construction of dental crown restorative materials.

Improving antibacterial performance of dental resin adhesive via co-incorporating fluoride and quaternary ammonium

Aiming to achieve improved antibacterial performance for dental application, sodium fluoride (NaF) nanoparticles and photopolymerizable N,N-dodecylvinylimidazole (DCV) were co-introduced into the dental resin adhesive at different ratios. The respective effect of NaF and DCV on adhesive curing kinetic, antibacterial activities against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Bacterial Flora of Human saliva (HSBF) were comprehensively evaluated. Then, the synergistic effects of NaF nanoparticles and DCV on adhesive performance were studied in terms of fluoride ion (F-) release, antibacterial activity, hydrophilicity, surface potential, cytotoxicity, and bonding strength. DCV monomer could polymerize with other adhesive monomers without influencing C=C double conversion rate, while the addition amount of DCV would affect the hydrophilicity and bonding strength of the cured adhesives. The cationic quaternary ammonium group could reduce the burst release of negative F- for the adhesive at a NaF/DCV ratio (1:1, 2%), hence achieving both non-contact and contact antibacterial activity in an extended term without causing cytotoxicity. Mixing NaF nanoparticles and DCV into the dental resin adhesive can slow down the initial burst release of F- and prolong the release-type antibacterial effect. The ionic interaction between F- and quaternary ammonium groups, as well as, the effect of DCV on adhesive hydrophilicity, simultaneously influence the release behavior of F-. Co-incorporation of quanternary ammonium and fluoride improves adhesive's antibacterial performance for dental application. Incorporating both NaF nanoparticles and DCV into dental resin adhesive could provide an efficient strategy for dental restoration as well as the prevention of secondary caries.

Comparative Analysis Of Adhesion Of Oral Microorganisms To The Surface Of Filling Materials

This article provides an overview of the current issues of the interaction of filling materials with the microflora of the oral cavity. An increase in the efficiency of restoration of dental hard tissues and the prevention of secondary caries, periodontal diseases by optimizing the choice of filling materials is considered, and the mechanism of adhesion of oral microorganisms to filling materials will also be studied. Purpose Study of the properties of composite filling materials in order to compare their ability to attach strains of various microorganisms contained in the oral cavity . Materials and research methods For the purpose of researching the topic, I will conduct a comprehensive medical and social examination of persons with restorations from various filling materials. Research results Study of adhesion of cariogenic microorganisms of the oral cavity on Estelite composites (Estelite LV Low Flow, Estelite Flow Quick, Estelite LV High Flow). Obtaining information on the effect of the organic matrix, the filling of composites on the adhesion ability of cariogenic microorganisms.

Remineralization effectiveness of adhesive containing amorphous calcium phosphate nanoparticles on artificial initial enamel caries in a biofilm-challenged environment.

Dental caries is closely associated with acid-producing bacteria, and Streptococcus mutans is one of the primary etiological agents. Bacterial accumulation and dental demineralization lead to destruction of bonding interface, thus limiting the longevity of composite. The present study investigated remineralization effectiveness of adhesive containing nanoparticles of amorphous calcium phosphate (NACP) in a stimulated oral biofilm environment. The enamel blocks were immersed in demineralization solution for 72 h to imitate artificial initial carious lesion and then subjected to a Streptococcus mutans biofilm for 24 h. All the samples then underwent 4-h demineralization in brain heart infusion broth with sucrose (BHIS) and 20-h remineralization in artificial saliva (AS) for 7 days. The daily pH of BHIS after 4-h incubation, lactic acid production, colony-forming unit (CFU) count, and content of calcium (Ca) and phosphate (P) in biofilm were evaluated. Meanwhile, the remineralization effectiveness of enamel was analyzed by X-ray diffraction (XRD), surface microhardness testing, transverse microradiography (TMR) and scanning electron microscopy (SEM). The NACP adhesive released abundant Ca and P, achieved acid neutralization, reduced lactic acid production, and lowered CFU count (P < 0.05). Enamel treated with NACP adhesive demonstrated the best remineralization effectiveness with remineralization value of 52.29 ± 4.79% according to TMR. Better microhardness recovery of cross sections and ample mineral deposits were also observed in NACP group. The NACP adhesive exhibited good performance in remineralizing initial enamel lesion with cariogenic biofilm. The NACP adhesive is promising to be applied for the protection of bonding interface, prevention of secondary caries, and longevity prolonging of the restoration.

The Antibacterial and Remineralizing Effects of Biomaterials Combined with DMAHDM Nanocomposite: A Systematic Review.

Researchers have developed novel nanocomposites that incorporate additional biomaterials with dimethylaminohexadecyl methacrylate (DMAHDM) in order to reduce secondary caries. The aim of this review was to summarize the current literature and assess the synergistic antibacterial and remineralizing effects that may contribute to the prevention of secondary caries. An electronic search was undertaken in MEDLINE using PubMed, Embase, Scopus, Web of Science and Cochrane databases. The initial search identified 954 papers. After the removal of duplicates and screening the titles and abstracts, 15 articles were eligible for this review. The amalgamation of 2-methacryloyloxyethyl phosphorylcholine (MPC) and silver nanoparticles (AgNPs) with DMAHDM resulted in increased antibacterial potency. The addition of nanoparticles of amorphous calcium phosphate (NACP) and polyamidoamine dendrimers (PAMAM) resulted in improved remineralization potential. Further clinical studies need to be planned to explore the antibacterial and remineralizing properties of these novel composites for clinical success.

Development of a Bioactive Flowable Resin Composite Containing a Zinc-Doped Phosphate-Based Glass.

Flowable resins used for dental restoration are subject to biofilm formation. Zinc has antibacterial properties. Thus, we prepared a zinc-doped phosphate-based glass (Zn-PBG) to dope a flowable resin and evaluated the antibacterial activity of the composite against Streptococcus mutans (S. mutans) to extrapolate the preventative effect toward secondary caries. The composites were prepared having 0 (control), 1.9, 3.8, and 5.4 wt.% Zn-PBG. The flexural strength, elastic modulus, microhardness, depth of cure, ion release, inhibition zone size, and number of colony-forming units were evaluated and analyzed using ANOVA. The flexural strength of the control was significantly higher than those of Zn-PBG samples (p < 0.05). However, all samples meet the International Standard, ISO 4049. The microhardness was not significantly different for the control group and 1.9 and 3.8 wt.% groups, but the 5.4 wt.% Zn-PBG group had a significantly lower microhardness (p < 0.05). Further, the composite resins increasingly released P, Ca, Na, and Zn ions with an increase in Zn-PBG content (p < 0.05). The colony-forming unit count revealed a significant reduction in S. mutans viability (p < 0.05) with increase in Zn-PBG content. Therefore, the addition of Zn-PBG to flowable composite resins enhances antibacterial activity and could aid the prevention of secondary caries.

Assessment Of The Clinical Effectiveness Of The Drug "Denta-Fluo" For Prevention Of Secondary Caries In Treatment With Deep Fluoridation Method

The article examines the assessment of the clinical efficacy of the drug "Denta-Fluo" for the prevention of secondary caries in the treatment of deep fluoridation.

Resin-Based Sealant with Bioactive Glass and Zwitterionic Material for Remineralisation and Multi-Species Biofilm Inhibition.

Since pits and fissures are the areas most commonly affected by caries due to their structural irregularity, bioactive resin-based sealant (RBS) may contribute to the prevention of secondary caries. This study aims to investigate the mechanical, physical, ion-release, enamel remineralisation, and antibacterial capabilities of the novel RBS with bioactive glass (BAG) and 2-methacryloyloxyethyl phosphorylcholine (MPC). For the synthesis, 12.5 wt% BAG and 3 wt% MPC were incorporated into RBS. The contact angle, flexural strength, water sorption, solubility, and viscosity were investigated. The release of multiple ions relating to enamel remineralisation was investigated. Further, the attachments of bovine serum albumin, brain heart infusion broth, and Streptococcus mutans on RBS were studied. Finally, the thickness and biomass of a human saliva-derived microsm biofilm model were analysed before aging, with static immersion aging and with thermocycling aging. In comparison to commercial RBS, BAG+MPC increased the wettability, water sorption, solubility, viscosity, and release of multiple ions, while the flexural strength did not significantly differ. Furthermore, RBS with MPC and BAG+MPC significantly reduced protein and bacteria adhesion and suppressed multi-species biofilm attachment regardless of the existence of aging and its type. The novel RBS has great potential to facilitate enamel remineralisation and suppress biofilm adhesion, which could prevent secondary dental caries.

Substituted Nano-Hydroxyapatite Toothpastes Reduce Biofilm Formation on Enamel and Resin-Based Composite Surfaces.

Background: Toothpastes containing nano-hydroxyapatite (n-HAp) substituted with metal ions provide calcium and phosphate ions to dental hard tissues, reducing demineralization, and promoting remineralization. Few data are available about the effect of these bioactive compounds on oral microbiota. Methods: This in vitro study evaluated the influence of two commercially-available substituted n-HAp-based toothpastes (α: Zn-carbonate substituted n-HAp; β: F, Mg, Sr-carbonate substituted n-HAp) on early colonization (EC, 12 h) and biofilm formation (BF, 24 h) by oral microbiota. Controls were brushed with distilled water. Artificial oral microcosm and Streptococcus mutans biofilms were developed using human enamel and a resin-based composite (RBC) as adherence surfaces. Two test setups, a shaking multiwell plate and a modified drip-flow reactor (MDFR), were used to simulate clinical conditions during the night (low salivary flow and clearance) and daytime, respectively. Energy-dispersive X-ray spectrometry (EDS) was used to evaluate specimens’ surfaces after toothpaste treatment. Fluoride release from β toothpaste was evaluated. Viable adherent biomass was quantified by MTT assay, and biofilms’ morphology was highlighted using confocal microscopy. Results: EDS showed the presence of remnants from the tested toothpastes on both adherence surfaces. β toothpaste showed significantly lower EC and BF compared to control using the artificial oral microcosm model, while α toothpaste showed lower EC and BF compared to control, but higher EC and BF compared to β toothpaste. The effect shown by β toothpaste was, to a minimal extent, due to fluoride release. Interestingly, this result was seen on both adherence surfaces, meaning that the tested toothpastes significantly influenced EC and BF even on RBC surfaces. Furthermore, the effect of toothpaste treatments was higher after 12 h than 24 h, suggesting that toothbrushing twice a day is more effective than brushing once. Conclusions: The efficacy of these treatments in reducing microbial colonization of RBC surfaces may represent a promising possibility in the prevention of secondary caries.

Prevention of Secondary Caries Using Resin-Based Pit and Fissure Sealants Containing Hydrated Calcium Silicate

The objective of this study was to investigate the effects of hydrated calcium silicate filler (hCS) on resin-based pit and fissure sealants’ acid neutralization, calcium ion release, and mechanical and physical properties. To produce the hCS filler, Portland cement (CS) was mixed with distilled water and ground into fine particles. The particles were then mixed with silanized glass filler and added to a photo-activated resin matrix. To evaluate the acid neutralization and calcium ion release properties, the specimens were immersed in a pH 4.0 lactic acid solution and distilled water for 28 days. Also, the flexural strength, depth of cure, water sorption, and solubility were tested. All of the groups containing hCS and CS required less than one minute to increase the pH from 4.0 to 5.5. With 50% hCS, the calcium ion release was higher than 50% CS in the distilled water at the initial time. The flexural strength and depth of cure decreased according to the increasing proportion of hCS added. The water sorption and solubility had an increasing trend as increasing proportions of hCS were added. These findings showed that pit and fissure sealant containing hCS exhibit superior acid neutralization and calcium release properties, and may be promising for caries-inhibiting dental material.

Effect of Polyols and Selected Dental Materials on the Ability to Create a Cariogenic Biofilm-On Children Caries-Associated Streptococcus Mutans Isolates.

Secondary caries is a disease associated with the formation of biofilm on the border of the tooth and dental filling. Its development is strongly influenced by the dietary sweet foods and the type of dental material. The aim of the study was to assess the effect of sweeteners on the ability of clinical Streptococcus mutans strains to form biofilm on dental materials. Strains were isolated from plaque samples from 40 pediatric patients from the 3–6 ICADS II group. The ability to form biofilm was tested on composite and glass ionomer dental materials used for milk teeth filling in the presence of sucrose, xylitol, sorbitol, and erythritol. The bacterial film mass after 12, 24, 48, and 72 h and the number of bacterial colonies significantly decreased (p < 0.01) compared to the initial value for 5% erythritol and sorbitol on examined materials. A greater inhibitory effect was noted for glass ionomers compared to composites. Sucrose and xylitol supported biofilm formation, while erythritol had the best inhibitory effect. The use of fluoride-releasing glass ionomers exerted an effect synergistic to erythritol, i.e., inhibited plaque formation and the amount of cariogenic S. mutans. Selection of proper type of dental material together with replacing sucrose with polyols can significantly decrease risk of secondary caries development. Erithritol in combination with glass ionomer seems to be the most effective in secondary caries prevention.