Dentin Remineralization Research Articles

Contemporary Update of Mouth Rinse

Introduction : Inadequate oral health control is a major risk of oral diseases. Regular home-based care is essential to maintain good oral hygiene. In particular, mouthrinses can support conventional tooth brushing in reducing accumulation of oral plaque. Effect : Antimicrobial mouthrinses are used as part of daily oral care to reduce plaque and gingivitis. Mouthrinses contains fluoride could help remineralization of enamel and dentin. The most common molecules contained in mouthrinses are chlorhexidine, essential oils, cetyl pyridinium chloride, triclosan, hyaluronic acid. Currently, chlorhexidine is the most efficacious compound, with both antiplaque and antibacterial activities. Similar results are reported for essential oils and cetyl pyridinium chloride, although with a somewhat reduced efficacy. Considering the adverse effects of chlorhexidine and its time-related characteristics, this molecule may best be indicated for acute/short term use, while essential oils and cetyl pyridinium chloride may be appropriate for long-term, maintenance treatment. Conclusion and suggestion : Antimicrobial mouthrinses are safe and effective, and when used in conjunction with brushing and flossing, they are an important method of reducing plaque and gingivitis. To improve compliance, dental health care professionals should adapt oral health care recommendations to fit patients' specific needs.

How effectively do hydraulic calcium-silicate cements re-mineralize demineralized dentin

ObjectiveTo characterize the chemical interplay and to quantify the re-mineralization potential of hydraulic calcium-silicate cements (hCSCs) at demineralized dentin. MethodsPairs of class-I cavities were prepared in non-carious human third molars. One dentin cavity was demineralized with 10% formic acid (5h); the other served as control. The cavities were filled with two resin-free hCSCs (Biodentine, Septodont; ProRoot MTA, Dentsply Sirona) or one resin-based hCSC (TheraCal LC, Bisco). After 1-week, 1-, 3-, and 6-month storage in simulated body fluid (SBF), polished specimen cross-sections were chemically characterized using Field-emission-gun Electron Probe Micro-Analysis (Feg-EPMA) and micro-Raman spectroscopy (μRaman). ResultsFeg-EPMA line-scans and elemental mappings confirmed early re-mineralization induced by all three hCSCs at 1week. The relative depth and intensity of re-mineralization were for the resin-free hCSCs in the range of 50.5%–84.8% and 68.1%–89.2%, respectively. Re-mineralization did not significantly differ for the storage periods (p>0.05). Significantly less re-mineralization was achieved by the resin-based hCSC TheraCal LC that reached only at 6months a re-mineralization level that was no longer significantly different from that achieved by the resin-free hCSCs at 1week (p>0.05). Re-mineralization of intertubular dentin, including tubular occlusion, was observed; Si was occasionally detected to have infiltrated the dentin tubules. Dentin re-mineralization by hCSCs was confirmed using μRaman that revealed an increased phosphate peak at 960cm−1. SignificancehCSCs do re-mineralize demineralized dentin. The resin-free cements induced re-mineralization at a higher speed/intensity than the resin-based hCSC. However, re-mineralization was incomplete for all hCSCs tested, this even at 6months.

Structural analysis of fluorine-containing bioactive glass nanoparticles synthesized by sol-gel route assisted by ultrasound energy.

In the last decades, studies about the specific effects of bioactive glass on remineralization of dentin were the focus of attention, due to their excellent regenerative properties in mineralized tissues. The incorporation of Fluorine in bioactive glass nanoparticles may result in the formation of fluorapatite (FAP), which is chemically more stable than hydroxyapatite or carbonated hydroxyapatite, and therefore is of interest for dental applications. The aim of this study was to synthesize and characterize a new system of Fluorine-containing bioactive glass nanoparticles (BGNPF). A sol-gel route assisted by ultrasound was used for the synthesis of BGNPF. The particles obtained were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), atomic force microscopy (AFM), X-ray diffraction (XRD), dynamic light scattering (DLS), nitrogen adsorption, and X-ray photoelectron spectroscopy (XPS). SEM micrographs showed that the particles are quite uniform spherical nanostructures, occurring agglomeration or partial sinterization of the particulate system after heat treatment. XRD and XPS analysis results suggest the formation of fluorapatite crystals embedded within the matrix of the bioactive glass nanoparticles. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 360-366, 2018.

Combining Bioactive Multifunctional Dental Composite with PAMAM for Root Dentin Remineralization.

Objectives. The objectives of this study were to: (1) develop a bioactive multifunctional composite (BMC) via nanoparticles of amorphous calcium phosphate (NACP), 2-methacryloyloxyethyl phosphorylcholine (MPC), dimethylaminohexadecyl methacrylate (DMAHDM) and nanoparticles of silver (NAg); and (2) investigate the effects of combined BMC + poly (amido amine) (PAMAM) on remineralization of demineralized root dentin in a cyclic artificial saliva/lactic acid environment for the first time. Methods. Root dentin specimens were prepared and demineralized with 37% phosphoric acid for 15 s. Four groups were prepared: (1) root dentin control; (2) root dentin with BMC; (3) root dentin with PAMAM; (4) root dentin with BMC + PAMAM. Specimens were treated with a cyclic artificial saliva/lactic acid regimen for 21 days. Calcium (Ca) and phosphate (P) ion concentrations and acid neutralization were determined. The remineralized root dentin specimens were examined via hardness testing and scanning electron microscopy (SEM). Results. Mechanical properties of BMC were similar to commercial control composites (p = 0.913). BMC had excellent Ca and P ion release and acid-neutralization capability. BMC or PAMAM alone each achieved slight mineral regeneration in demineralized root dentin. The combined BMC + PAMAM induced the greatest root dentin remineralization, and increased the hardness of pre-demineralized root dentin to match that of healthy root dentin (p = 0.521). Significance. The excellent root dentin remineralization effects of BMC + PAMAM were demonstrated for the first time. BMC + PAMAM induced effective and complete root dentin remineralization in an acid challenge environment. The novel BMC + PAMAM method is promising for Class V and other restorations to remineralize and protect tooth structures.

The remineralization effectiveness of PAMAM dendrimer with different terminal groups on demineralized dentin in vitro

The aim of this study was to examine the dentin remineralization extent that poly(amido amine) (PAMAM) induces quantitatively, and select the most effective kind of PAMAM with a certain terminal group for dentin remineralization, both for the first time.

Intrafibrillar mineralization of polyacrylic acid-bound collagen fibrils using a two-dimensional collagen model and Portland cement-based resins.

The biomimetic remineralization of apatite-depleted dentin is a potential method for enhancing the durability of resin-dentin bonding. To advance this strategy from its initial proof-of-concept design, we sought to investigate the characteristics of polyacrylic acid (PAA) adsorption to desorption from type I collagen and to test the mineralization ability of PAA-bound collagen. Portland cement and β-tricalcium phosphate (β-TCP) were homogenized with a hydrophilic resin blend to produce experimental resins. The collagen fibrils reconstituted on nickel (Ni) grids were mineralized using different methods: (i) group I consisted of collagen treated with Portland cement-based resin in simulated body fluid (SBF); (ii) group II consisted of PAA-bound collagen treated with Portland cement-based resin in SBF; and (iii) group III consisted of PAA-bound collagen treated with β-TCP-doped Portland cement-based resin in deionized water. Intrafibrillar mineralization was evaluated using transmission electron microscopy. We found that a carbonyl-associated peak at pH 3.0 increased as adsorption time increased, whereas a hydrogen bond-associated peak increased as desorption time increased. The experimental resins maintained an alkaline pH and the continuous release of calcium ions. Apatite was detected within PAA-bound collagen in groups II and III. Our results suggest that PAA-bound type I collagen fibrils can be mineralized using Portland cement-based resins.

Poly (amido amine) and nano-calcium phosphate bonding agent to remineralize tooth dentin in cyclic artificial saliva/lactic acid

The objectives of this study were to develop a novel method to remineralize dentin lesions, and investigate the remineralization effects of poly (amido amine) (PAMAM) dendrimer plus a bonding agent with nanoparticles of amorphous calcium phosphate (NACP) in a cyclic artificial saliva/lactic acid environment for the first time. Dentin lesions were produced via phosphoric acid. Four groups were tested: (1) dentin control, (2) dentin with PAMAM, (3) dentin with NACP bonding agent, and (4) dentin with PAMAM plus NACP bonding agent. Specimens were treated with cyclic artificial saliva/lactic acid. The remineralized dentin was examined using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), hardness and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). NACP bonding agent yielded a dentin shear bond strength similar to commercial controls (Prime & Bond NT, Dentsply; Scotchbond Multi-purpose, 3M) (p>0.1). Increasing NACP in bonding agent from 0 to 40% did not affect bond strength. NACP bonding agent neutralized the acid and released Ca ions with concentrations of 4 to 20mmol/L, and P ions of 2 to 9mmol/L. PAMAM or NACP bonding agent alone achieved slight remineralization. The PAMAM+NACP group achieved the greatest dentin remineralization p<0.05). At 20days, PAMAM+NACP increased the hardness of pre-demineralized dentin to reach the normal dentin hardness (p>0.1). In conclusion, superior remineralization of PAMAM+NACP bonding agent was demonstrated for the first time. PAMAM+NACP bonding agent induced dentin remineralization under acid challenge, when conventional remineralization methods such as PAMAM alone did not work well. The novel PAMAM+NACP bonding agent method is promising to improve the longevity of resin-dentin bonds, inhibit caries, and protect teeth.

Ex vivo detection and characterization of remineralized carious dentin, by nanoindentation and single point Raman spectroscopy, after amalgam restoration

The aim of this study was to assess the mechanical and chemical performance of sound and caries‐affected dentin, after Zn‐free versus containing amalgam restorations placement and thermocycling. Dentin surfaces were studied by Atomic Force Microscopy analysis for surface morphological characterization (including fibril diameter assessment), nano‐indentation (to measure nano‐hardness‐Hi and modulus of Young‐Ei), and single point Raman spectroscopy for chemical analysis. Measurements were performed before amalgam placement, after amalgam removal, and after 3 months of thermocycling (100 000 cy/5 °C and 55 °C). Restorations increased both Hi and Ei at intertubular dentin of caries‐affected dentin. The highest values of Hi were achieved at intertubular dentin after restoring with Zn‐containing amalgams. Remineralization of dentin was attributed to the increase of both amorphous and crystalline new mineral, as lower degrees of crystal imperfections in junction with crystal disorders, and improvement in structural stability of collagen were found. Higher presence of minerals was also confirmed after the decrease of fluoridated apatite. The increase of bands assigned to vibration of carbonate calcium phosphate contributed to a decrease of crystallinity. Copyright © 2016 John Wiley &amp; Sons, Ltd.

Frequency of intake and amount of fluoride in milk for remineralisation of artificial caries on enamel and dentine: Ex vivo/in situ study

ObjectivesThis study analysed the effect of frequency of intake and amount of fluoride in milk on the remineralisation of artificial enamel and dentine caries lesions ex vivo/in situ. Materials and methodsPre-demineralised bovine enamel and dentine slabs were randomly allocated into 5 groups and fixed in removable appliances used by subjects for 7days in each phase. Each treatment comprised milk containing 2.5ppm fluoride daily (T1), or every other day (T2), 5.0ppm F daily (T3), or every other day (T4) or no treatment (T5). ResultsEnamel alterations were quantified by surface hardness recovery (%SHR) and transversal microradiography (TMR), and in dentine by TMR only. Data were analysed by ANOVA and Tukey’s test (p<0.05). For enamel, the highest %SHR was found for T1 and T3 compared to control, without significant differences between them. All groups showed positive values of ΔΔZ − T1 (247.3±198.5); T2 (110.9±303.2); T3 (226.0±299.2); T5 (5.0±288.0), except T4 (−274.5±407.3). For dentine, the only group that presented remineralisation was T2 (350.0±657.5). ConclusionsFluoridated milk daily seems to have higher remineralising effect on enamel than its use every other day. Dentine, does not seem to benefit from daily use of fluoridated milk.

Scanning electron microscopic analysis of using agarose hydrogel microenvironment to create enamel prism-like tissue on dentine surface

ObjectiveTo investigate remineralisation of dentine in the hydrogel microenvironment for the management of hypersensitivity. MethodsHuman dentine slices were prepared from extracted sound human molars. They were acid-etched with phosphoric acid and put into the polyethylene tubes. The etched dentine surfaces were covered by a 2-mm-thick layer of CaCl2 agarose hydrogel. Another 2-mm-thick layer of ion-free agarose hydrogel was added on top of the CaCl2 agarose hydrogel. They were immersed into a solution containing phosphate and fluoride after gelification. The solution was replaced every 24h and the agarose hydrogels were replaced every 48h. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to evaluate the formed crystals on dentine surface after 2, 4 and 6days. SEM was used to study the mineral formed in the replaced agarose hydrogels. ResultsObservation under SEM showed that crystals occluded the dentinal tubules and an enamel prism-like tissue formed on the etched dentine surface. XRD and FTIR analyses confirmed the crystals were hydroxyapatite. Numerous calcium phosphate globules were found in the replaced calcium chloride agarose hydrogel. ConclusionThe hydrogel acts as the remineralisation microenvironment to initiate occlusion of dentinal tubules and formation of enamel prisms-like tissue on human dentine surface. Clinical significanceRemineralisation of dentine induced in this hydrogel microenvironment can be an alternative therapeutic technique for the management of dentine hypersensitivity.

Zinc-Containing Restorations Create Amorphous Biogenic Apatite at the Carious Dentin Interface: A X-Ray Diffraction (XRD) Crystal Lattice Analysis

The aim of this research was to assess the ability of amalgam restorations to induce amorphous mineral precipitation at the caries-affected dentin substrate. Sound and caries-affected dentin surfaces were subjected to both Zn-free and Zn-containing dental amalgam restorations. Specimens were submitted to thermocycling (100,000 cycles/5°C-55°C, 3 months). Dentin surfaces were studied by atomic force microscopy (nanoroughness), X-ray diffraction, field emission scanning electron microscopy, and energy-dispersive analysis, for physical and morphological surface characterization. Zn-containing amalgam placement reduced crystallinity, crystallite size, and grain size of calcium phosphate crystallites at the dentin surface. Both microstrain and nanoroughness were augmented in caries-affected dentin restored with Zn-containing amalgams. Caries-affected dentin showed the shortest mineral crystallites (11.04 nm), when Zn-containing amalgams were used for restorations, probably leading to a decrease of mechanical properties which might favor crack propagation and deformation. Sound dentin restored with Zn-free amalgams exhibited a substantial increase in length of grain particles (12.44 nm) embedded into dentin crystallites. Zn-containing amalgam placement creates dentin mineralization and the resultant mineral was amorphous in nature. Amorphous calcium phosphate provides a local ion-rich environment, which is considered favorable for in situ generation of prenucleation clusters, promotong further dentin remineralization.

Dentin remineralization in acid challenge environment via PAMAM and calcium phosphate composite

ObjectivesThe objective of this study was to investigate the effects of poly (amido amine) (PAMAM), composite with nanoparticles of amorphous calcium phosphate (NACP), and the combined PAMAM+NACP nanocomposite treatment, on remineralization of demineralized dentin in a cyclic artificial saliva/lactic acid environment for the first time. MethodsDentin specimens were prepared and demineralized with 37% phosphoric acid for 15s. Four groups were prepared: (1) dentin control, (2) dentin coated with PAMAM, (3) dentin with NACP composite, (4) dentin with PAMAM+NACP. Specimens were treated with a cyclic artificial saliva/lactic acid regimen for 21days. Acid neutralization and calcium (Ca) and phosphate (P) ion concentrations were measured. The remineralized dentin specimens were examined by scanning electron microscopy (SEM) and hardness testing. ResultsNACP nanocomposite had mechanical properties similar to commercial control composites (p>0.1). NACP composite had acid-neutralization and Ca and P ion release capability. PAMAM or NACP composite each alone achieved remineralization and increased the hardness of demineralized dentin (p<0.05). PAMAM+NACP nanocomposite achieved the greatest mineral regeneration in demineralized dentin and the greatest hardness increase in demineralized dentin, which approached the hardness of healthy dentin (p>0.1). SignificanceThe superior remineralization efficacy of PAMAM+NACP was demonstrated for the first time. PAMAM+NACP induced remineralization in demineralized dentin in an acid challenge environment, when conventional remineralization methods such as PAMAM did not work well. The novel PAMAM+NACP composite approach is promising for a wide range of dental applications to inhibit caries and protect tooth structures.

Bonding performance of experimental bioactive/biomimetic self-etch adhesives doped with calcium-phosphate fillers and biomimetic analogs of phosphoproteins

ObjectivesThis study examined the bonding performance and dentin remineralization potential of an experimental adhesive containing calcium-phosphate (Ca/P) micro-fillers, and self-etching primers doped with phosphoprotein biomimetic analogs (polyacrylic acid-(PAA) and/or sodium trimetaphosphate-(TMP)). MethodsExperimental self-etching primers doped with biomimetic analogs (PAA and/or TMP), and an adhesive containing Ca2+, PO4−3-releasing micro-fillers (Ca/P) were formulated. Sound human dentin specimens were bonded and cut into sticks after aging (24h or 6 months) under simulated pulpal pressure (20cm H2O), and tested for microtensile bond strength (μTBS). Results were analyzed using two-way ANOVA and Tukey’s test (p<0.05). Interfacial silver nanoleakage was assessed using SEM. Remineralization of EDTA-demineralized dentin was assessed through FTIR and TEM ultrastructural analysis. ResultsApplication of the Ca/P-doped adhesive with or without dentin pre-treatments with the primer containing both biomimetic analogs (PAA and TMP) promoted stable μTBS over 6 months. Conversely, μTBS of the control primer and filler-free adhesive significantly decreased after 6 months. Nanoleakage decreased within the resin-dentin interfaces created using the Ca/P-doped adhesives. EDTA-demineralized dentin specimens treated the Ca/P-doped adhesive and the primer containing PAA and TMP showed phosphate uptake (FTIR analysis), as well as deposition of needle-like crystallites at intrafibrillar level (TEM analysis). SignificanceThe use of Ca/P-doped self-etching adhesives applied in combination with analogs of phosphoproteins provides durable resin-dentin bonds. This approach may represent a suitable bonding strategy for remineralization of intrafibrillar dentin collagen within the resin-dentin interface.

Effect of Nanohydroxyapatite with and without Chlorhexidine on Remineralization of Carious Dentine at Different Intervals: An in vivo study

This invivo study was carried out to evaluate the effect of nanohydroxyapatite (n-HAp); applied with or without prior application of chlorhexidine (CHX), on remineralization of caries- affected and caries infected dentine types. Forty molars in eight patients having class I caries and no pulpal involvement were selected. In each selected molar, caries was removed except from the pulpal floor. Thereafter, molars were divided into two groups (n= 20) according to the type of carious dentine left on the pulpal floor; caries- affected or infected dentine. Each group was further subdividedinto two subgroups (n=10) according to the material that was applied on carious dentine; n-HAp with or without 2% CHX. All cavities were finally sealed with glass ionomer restoration. Assessment of mineral density was performed at base line, one and three months using digitized radiography. The results showed increased mineral density in caries- affected dentine group; with no significant difference neither n-HAp was applied with or without CHX, nor was the application time increased more than one month. In caries- infected dentine group, however, mineral density was decreased. Suchdecrease was significantly evident at the third month; when n-HAp was applied without CHX. It was concluded that n- HAp could only promote remineralization of cariesaffected dentine. Additionally, although application of CHX prior to n-HAp showed no considerable influence on remineralization, yet, it could be recommended in case of caries- infected dentine as an antiseptic.

Glutaraldehyde-induced remineralization improves the mechanical properties and biostability of dentin collagen

The purpose of this study was to induce a biomimetic remineralization process by using glutaraldehyde (GA) to reconstruct the mechanical properties and biostability of demineralized collagen. Demineralized dentin disks (35% phosphoric acid, 10s) were pretreated with a 5% GA solution for 3min and then cultivated in a calcium phosphate remineralization solution. The remineralization kinetics and superstructure of the remineralization layer were evaluated by Raman spectroscopy, transmission electron microscopy, scanning electron microscopy and nanoindentation tests. The biostability was examined by enzymatic degradation experiments. A significant difference was found in dentin remineralization process between dentin with and without GA pretreating. GA showed a specific affinity to dentin collagen resulting in the formation of a cross-linking superstructure. GA pretreating could remarkably shorten remineralization time from 7days to 2days. The GA-induced remineralized collagen fibrils were well encapsulated by newly formed hydroxyapatite mineral nanocrystals. With the nano-hydroxyapatite coating, both the mechanical properties (elastic modulus and hardness) and the biostability against enzymatic degradation of the collagen were significantly enhanced, matching those of natural dentin. The results indicated that GA cross-linking of dentin collagen could promote dentin biomimetic remineralization, resulting in an improved mechanical properties and biostability. It may provide a promising tissue-engineering technology for dentin repair.

Application of Fluorine Containing Bioactive Glass Nanoparticles in Dentin Hypersensitivity Treatment

The effect of Bioactive Glass on remineralization of dentin is the focus of the present study due to its excellent regenerative properties in mineralized tissues. It is known that the effect of Bioactive Glass can be enhanced at the nanoscale. In addition, the incorporation of Fluorine in the glass structure makes possible the formation of Fluorapatite (FAP). The aim of this study was to synthesize and characterize a new system of Fluorine containing Bioactive Glass Nanoparticles (FBGNP), and evaluate the potential for in vitro dentin remineralization by occlusion of dentinal tubules. The FBGNPs produced were uniform, with spherical shape and nanoscale size. Agglomeration or partial sinterization of the particulate system probably occurred after heat treatment. The results suggest the formation of FAP crystals embedded within the matrix of the Bioactive Glass. The gel containing FBGNP produced was effective in obliterating the dentinal tubules in vitro, showing that FBGNP is a potential material to be used for treatment of dentin hypersensitivity.

In vitro dentine remineralization with a potential salivary phosphoprotein homologue

ObjectiveAdvantages of introducing a salivary phosphoprotein homologue under standardized in vitro conditions to simulate the mineral-stabilizing properties of saliva have been proposed. This study longitudinally investigates the effects of casein, incorporated as a potential salivary phosphoprotein homologue in artificial saliva (AS) solutions with/without fluoride (F) on in vitro dentine lesion remineralization. DesignThin sections of bovine root dentine were demineralized and allocated randomly into 6 groups (n=18) having equivalent mineral loss (ΔZ) after transverse microradiography (TMR). The specimens were remineralized using AS solutions containing casein 0μg/ml, F 0ppm (C0–F0); casein 0μg/ml, F 1ppm (C0–F1); casein 10μg/ml, F 0ppm (C10–F0); casein 10μg/ml, F 1ppm (C10–F1); casein 100μg/ml, F 0ppm (C100–F0) or casein 100μg/ml, F 1ppm (C100–F1) for 28days with TMR taken every 7 days. ResultsSurface mineral precipitation, evident in group C0–F1, was apparently inhibited in groups with casein incorporation. Repeated measures ANOVA with Bonferroni correction revealed higher ΔZ for non-F and non-casein groups than for their counterparts (p<0.001). Subsequent multiple comparisons showed that mineral gain was higher (p<0.001) with 10μg/ml casein than with 100μg/ml when F was present in the earlier stages of remineralization, with both groups achieving almost complete remineralization after 28 days. ConclusionCasein is a potential salivary phosphoprotein homologue that could be employed for in vitro dentine remineralization studies. Concentration related effects may be clinically significant and thus must be further examined.

Создание рациональной лекарственной формы для лечения кариеса дентина

The wide distribution of caries determines not only its clinical, but also its social value. Remineralizing gel was produced for the treatment of medium and deep caries, it contains basic mineralizing ions - calcium, phosphorus and fluorine at the same time. The gel has a structured water space, it provides a protective effect on the interaction of Са 2+, НРО4 2- and F¯. This allows you to retain components in a free active state and to provide a substantial increase in their penetration into the dentin. The simulation is carried out on the ratio of phosphorus to calcium of dentin 2:1. Gel usage in case of dentin remineralization on the first stage of deep caries treatment allows us to fill cavities without lining treatment, therefore, this gel may find wide application in dentistry.

Zinc-modified nanopolymers improve the quality of resin-dentin bonded interfaces.

Demineralized collagen fibers at the hybrid layer are susceptible to degradation. Remineralization may aid to improve bond longevity. The aim of the present study was to infiltrate zinc and calcium-loaded polymeric nanoparticles into demineralized dentin to facilitate hybrid layer remineralization. Zinc or calcium-loaded polymeric nanoparticles were infiltrated into etched dentin, and Single Bond Adhesive was applied. Bond strength was tested after 24h and 6months storage. Nanomechanical properties, dye-assisted confocal laser microscopy, and Masson's trichrome staining evaluation were performed to assess for the hybrid layer morphology, permeability, and remineralization ability after 24h and 3months. Data were analyzed by ANOVA and Student-Newman-Keuls multiple comparisons tests (p<0.05). Immediate bond strength was not affected by nanoparticles infiltration (25 to 30MPa), while after 6months, bond strengths were maintained (22 to 24MPa). After 3months, permeability occurred only in specimens in which nanoparticles were not infiltrated. Dentin remineralization, at the bottom of the hybrid layer, was observed in all groups. After microscopy analysis, zinc-loaded nanoparticles were shown to facilitate calcium deposition throughout the entire hybrid layer. Young's modulus at the hybrid layer increased from 2.09 to 3.25GPa after 3months, in specimens with zinc nanoparticles; meanwhile, these values were reduced from 1.66 to 0.49GPa, in the control group. Infiltration of polymeric nanoparticles into demineralized dentin increased long-term bond strengths. Zinc-loaded nanoparticles facilitate dentin remineralization within the complete resin-dentin interface. Resin-dentin bond longevity and dentin remineralization at the hybrid layer were facilitated by zinc-loaded nanoparticles.

Biomineralization and Biomaterial Considerations in Dentin Remineralization

ABSTRACTDentin is a composite hard tissue, comprising of inorganic and organic matrices, and regulated by many proteins during development. The demineralization of dentin results from the loss of inorganic matrix [mainly hydroxyapatite (HAP)], but the organic matrix (mainly type I collagen) will sustain for a period of time after demineralization. Over the past decade, there has been a growing interest on the remineralization of demineralized dentin, primarily in connection with minimally invasive caries management. More and more biomaterials and methods are currently being evaluated to achieve newer approaches for the remineralization of demineralized dentin. These strategies are mostly based on biomimetic approaches and aim to achieve the characteristics of natural hard tissue. This article will present a complete review on the basic compositions and properties of dentin, which formed the basis for the biomimetic remineralization of demineralized dentin.How to cite this articleZhang X, Xiao Z, Wang H, Kishen A. Biomineralization and Biomaterial Considerations in Dentin Remineralization. J Oper Dent Endod 2016;1(1):7-12.