-
Dental Bleaching with Phthalocyanine Photosensitizers: Effects on Dentin Color and Collagen Content.Molecules (Basel, Switzerland) May 2023With the increasing demand for tooth bleaching in esthetic dentistry, its safety has been the focus of a comprehensive body of literature. In this context, the aim of...
With the increasing demand for tooth bleaching in esthetic dentistry, its safety has been the focus of a comprehensive body of literature. In this context, the aim of the present study was to evaluate the application effects of pentalysine β-carbonylphthalocyanine zinc (ZnPc(Lys))-mediated photodynamic therapy in dentin bleaching and its effects on dentin collagen. We first established a new and reproducible tooth staining model using dentin blocks stained by Orange II and then bleached with ZnPc(Lys) (25 μM) and hydrogen peroxide (10% or 30%). Data were analyzed with one- and two-way ANOVA and a significance level of < 0.05. ZnPc(Lys) effectively bleached the dentin samples to an extent comparable to hydrogen peroxide at either 10% or 30% concentrations. Further studies on the dentin morphology, chemical element distribution, and protein constituents, using an electron microscope, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and SDS-PAGE, demonstrated that treatment with the photosensitizer preserved the dentin structure and, at the same time, the major organic component, collagen type I. For comparison, hydrogen peroxide (10% or 30%) treatment significantly degraded the collagen protein. This work indicated that the photosensitizer exerts potent bleaching effects on dentin staining; importantly, does not damage dentin and its collagen content; and opens up a new strategy to further explore various photosensitizers for the bleaching of both tooth enamel and dentin.
Topics: Hydrogen Peroxide; Tooth Bleaching; Photosensitizing Agents; Dentin; Hypochlorous Acid; Collagen; Color
PubMed: 37241963
DOI: 10.3390/molecules28104223 -
International Journal of Nanomedicine 2023To investigate the effects of proanthocyanidins (PA), myricetin, resveratrol, and kaempferol on the modification of dentin collagen and the inhibition of matrix...
OBJECTIVE
To investigate the effects of proanthocyanidins (PA), myricetin, resveratrol, and kaempferol on the modification of dentin collagen and the inhibition of matrix metalloproteinase (MMP) activity, and to evaluate their contributions to the biomimetic remineralization and resin-dentin bonding performance.
METHODS
Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and in situ zymography were applied to verify the collagen modification and MMP activity inhibition induced by these four polyphenols. Scanning electron microscopy/energy dispersive spectrometer (SEM/EDS) analysis, X-ray diffraction (XRD), ATR-FTIR, Vickers hardness numbers (VHN), and micro-computed tomography (micro-CT) were performed to characterize the remineralized dentin. Microtensile bond strength (μTBS) and nanoleakage were investigated to evaluate the effects of the four polyphenols on resin-dentin bonding durability.
RESULTS
ATR-FTIR and in situ zymography confirmed that these four polyphenols could modify dentin collagen and inhibit MMP activity, respectively. Chemoanalytic characterization exhibited the efficacies of the four polyphenols in promoting dentin biomimetic remineralization. The surface hardness of PA-pretreated dentin was the greatest. Micro-CT results demonstrated that the PAs group possessed the highest amount of dentin surface minerals and the lowest amount of deep-layer minerals. The surface and deep-layer mineral contents of the Myr group were higher than Res and Kae groups. Treatment with these four polyphenols significantly increased the initial μTBS compared with the control group without primer conditioning. μTBS decreased significantly during aging, and the decrease was more severe in the PAs and Kae groups than in the Myr and Res groups. With or without aging, the polyphenol groups exhibited relatively less fluorescence. However, the Myr and Res groups showed less serious nanoleakage after aging.
CONCLUSION
PA, myricetin, resveratrol, and kaempferol can modify dentin collagen, inhibit MMP activity, promote biomimetic remineralization, and improve resin-dentin bond durability. Compared with PA and kaempferol, myricetin and resveratrol are more effective in improving resin-dentin bonding.
Topics: Kaempferols; Polyphenols; Resveratrol; X-Ray Microtomography; Dentin; Minerals; Proanthocyanidins; Nanoparticles; Collagen; Tensile Strength; Materials Testing; Dental Bonding; Resin Cements
PubMed: 36998600
DOI: 10.2147/IJN.S395631 -
Tissue Engineering. Part B, Reviews Aug 2022The recent discovery of mesenchymal stem cells within periapical lesions (PL-MSC) has presented novel opportunities for managing periradicular diseases in adult teeth by... (Review)
Review
The recent discovery of mesenchymal stem cells within periapical lesions (PL-MSC) has presented novel opportunities for managing periradicular diseases in adult teeth by way of enhancing tissue regeneration. This discovery coincides with the current paradigm shift toward biologically driven treatment strategies in endodontics, which have typically been reserved for non-vital immature permanent teeth. One such approach that shows promise is utilizing local endogenous non-collagenous dentine extracellular matrix components (dECM) to recruit and upregulate the intrinsic regenerative capacity of PL-MSCs . At picogram levels, these morphogens have demonstrated tremendous ability to enhance the cellular activities in and animal studies that would otherwise be necessary for periradicular regeneration. Briefly, these include proliferation, viability, migration, differentiation, and mineralization. Therefore, topical application of dECMs during ortho- or retrograde root canal treatment could potentially enhance and sustain the regenerative mechanisms within diseased periapical tissues that are responsible for attaining favorable clinical and radiographic outcomes. This would provide many advantages when compared with conventional antimicrobial-only therapies for apical periodontitis (AP), which do not directly stimulate healing and have had stagnant success rates over the past five decades despite significant advances in operative techniques. The aim of this narrative review was to present the novel concept of exploiting endogenous dECMs as clinical tools for treating AP in mature permanent teeth. A large scope of literature was summarized to discuss the issues associated with conventional treatment modalities; current knowledge surrounding PL-MSCs; composition of the dECM; inductive potentials of dECM morphogens in other odontogenic stem cell niches; how treatment protocols can be adapted to take advantage of dECMs and PL-MSCs; and finally, the challenges currently impeding successful clinical translation alongside directions for future research. Impact statement Apical periodontitis (AP) is an inflammatory condition that is associated with a great degree of morbidity and ultimately leads to tooth loss. The purpose of this review was to summarize the current evidence pertaining to stem cell therapy in endodontics and present a novel clinical methodology through which they may be utilized to address AP. A comprehensive overview of the basic science, clinical translation, and potential challenges are presented in this review.
Topics: Animals; Cell Differentiation; Dentin; Periapical Periodontitis; Root Canal Therapy; Tissue Engineering
PubMed: 34309453
DOI: 10.1089/ten.TEB.2021.0074 -
The Journal of International Medical... Feb 2021The effects of saliva on demineralized dentin and silver diamine fluoride (SDF) were investigated
OBJECTIVE
The effects of saliva on demineralized dentin and silver diamine fluoride (SDF) were investigated
METHODS
Dentin samples stored in deionized water (DIW), buffer solution (BS), basal medium mucin (BMM), and unstimulated whole saliva (UWS) were demineralized for 3 days and immersed in the same storage media. SDF as a 38 mass% solution was applied to the dentin samples for 3 minutes after they had been replaced in their respective medium. Surfaces were analyzed by scanning electron microscopy, energy-dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD).
RESULTS
Scanning electron microscopy showed various surface deposits and coatings, including occlusion of dentinal tubules. DIW resulted in the thinnest coating, whereas BMM resulted in the thickest. EDX and XPS showed the formation of metallic silver and silver compounds in all four media, with the greatest formation in BS. XRD indicated that the main product was silver chloride except in DIW. Sulphur was found in BMM and UWS. EDX and XPS detected fluoride and XRD detected calcium fluoride and fluorohydroxyapatite in BS, BMM, and UWS.
CONCLUSION
The interaction between SDF and demineralized dentin was dependent upon the storage medium. BMM provided an outcome most similar to human saliva.
Topics: Dentin; Fluorides, Topical; Humans; Quaternary Ammonium Compounds; Silver Compounds
PubMed: 33615855
DOI: 10.1177/0300060520985336 -
Dental Materials Journal Oct 2022This study investigated how the double application of adhesives and dentin moisture level influence the microtensile bond strength (µTBS) of universal adhesives...
This study investigated how the double application of adhesives and dentin moisture level influence the microtensile bond strength (µTBS) of universal adhesives containing different hydrophilic monomers to bur-cut dentin. Four universal adhesives (Scotchbond Universal, Clearfil Universal Bond Quick, Prime&Bond Universal, BeautiBond Universal) were applied to wet and dry bur-cut dentin either in one or two layers. The µTBS test was performed after 25,000 thermal cycles, and scanning electron microscopy was used for the analysis of failure mode and interfacial ultrastructure. Double application significantly improved µTBS on wet dentin (p<0.001), but the effect was not significant on dry dentin (p>0.050). Double application also enhanced the formation of resin tags and limited voids within the adhesive layer of BeautiBond Universal. Dentin moisture had a significant effect on µTBS only if the adhesives were applied in a single layer (p=0.007). Except for Prime&Bond Universal, the tested universal adhesives performed better on dry dentin.
Topics: Adhesives; Dental Bonding; Dental Cements; Dentin; Dentin-Bonding Agents; Materials Testing; Resin Cements; Tensile Strength
PubMed: 35676046
DOI: 10.4012/dmj.2021-310 -
Acta Bio-medica : Atenei Parmensis Dec 2023Congenital heart disease (CHD) is an abnormality in the structure or function of the cardio-circulatory system present at birth and the ventricular septal defect (VSD)...
Congenital heart disease (CHD) is an abnormality in the structure or function of the cardio-circulatory system present at birth and the ventricular septal defect (VSD) is the most common CHD in children. This study aimed to determine any differences in the histological structure of primary teeth between both healthy children and those children with ventricular septal defects in Erbil City. Methods enrolled children were divided into two groups. Group I (control) & group II (CHD) aged between 6-10 years old. A total of 44 children were collected, (22 children) in each group. Enamel, dentin, and odontoblast layers were examined histologically. Unpaired t-test used for statistical analysis. Results: The histopathological sections showed a significant difference in enamel, dentin, and odontoblast layer thickness (255.8 ± 41.68- 406.4 ±46.39), (1156 ± 116.0 - 1320 ± 117.4) and (29.74 ± 7.66 -41.38 ± 12.06) respectively, with p values (P < 0.0001) for enamel and dentin layer, and P < 0.0004 for odontoblast layer. A study of the images in the CHD group showed that the tooth tissue lost its integrity and cohesion in some places, and the thickness of the enamel and dentin layer in this group was significantly reduced compared to group I. Tissue loss in enamel, pulp, and dentin cell were observed. Also, connective tissue layers in the pulp were disrupted. Conclusions: CHD can alter the natural structure formation of primary teeth. Histologically, enamel, dentin, and odontoblasts layer thickness reduction are found in primary teeth in children with ventricular septal defects.
Topics: Infant, Newborn; Humans; Child; Dentin; Odontoblasts; Heart Defects, Congenital; Tooth, Deciduous; Heart Septal Defects, Ventricular
PubMed: 38054687
DOI: 10.23750/abm.v94i6.14567 -
International Journal of Nanomedicine 2021Dentin hypersensitivity (DH) is a common dental clinical condition presented with a short and sharp pain in response to physical and chemical stimuli. Currently no...
BACKGROUND
Dentin hypersensitivity (DH) is a common dental clinical condition presented with a short and sharp pain in response to physical and chemical stimuli. Currently no treatment regimen demonstrates long-lasting efficacy in treating DH, and unesthetic yellow tooth color is a concern to many patients with DH.
AIM
To develop a bi-functional material which can occlude dentinal tubules in-depth and remineralize dentin for long-lasting protection of the dentin-pulp complex from stimuli and bleach the tooth at the same time.
METHODS
A mixture containing CaO, HPO, polyethylene glycol and HO at a specific ratio was mechanically ground using a planetary ball. The mineralizing complex paste was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Dentin was exposed to the synthesized paste for 8 h and 24 h . The mineralizing property was evaluated using SEM and microhardness tests. Red tea-stained tooth slices were exposed to the synthesized paste for 8 h and 24 h . The bleaching effect was characterized by a spectrophotometer.
RESULTS
The complex paste had very a fine texture, was injectable, and had a gel-like property with 2.6 (mass/volume) % HO concentration. The X-ray diffraction pattern showed that the inorganic phase was mainly monetite (CaHPO). The mineralizing complex paste induced the growth of inorganic crystals on the dentin surface and in-depth occlusion of dentin tubules by up to 80 μm. The regenerated crystals were integrated into the dentin tissue on the dentin surface and the wall of dentinal tubules with a microhardness of up to 126 MPa (versus 137 Mpa for dentin). The paste also bleached the stained dental slices.
CONCLUSION
The mineralizing complex paste is a promising innovative material for efficient DH management by remineralizing dentin and in-depth occlusion of dentin tubules, as well as tooth bleaching.
Topics: Calcium Phosphates; Dentin; Hardness; Humans; Hydrogen Peroxide; Phosphoric Acids; Tooth Bleaching; Tooth Remineralization; X-Ray Diffraction
PubMed: 33442248
DOI: 10.2147/IJN.S287393 -
Brazilian Dental Journal 2022The aim of this study was to evaluate the efficacy of an ultrasound device and the dentin surface morphology after removal of the caries dentin lesions by removal rate...
The aim of this study was to evaluate the efficacy of an ultrasound device and the dentin surface morphology after removal of the caries dentin lesions by removal rate and scanning electron microscopy (SEM). The Knoop hardness test on the bovine dentin blocks (n = 20, 4x4x2mm) was performed to standardize the samples and only those with 38 ± 2 KHN were included. The dentin blocks were submitted to induction of artificial caries lesions, using the bacterial model. Strains of Streptococcus mutans and Lactobacillus acidophilus were used for 7 days. The caries dentin lesion was removed for 1 min, according to two methods: G1 - carbide bur under low-speed rotation (control group) and G2 - ultrasound device under refrigeration. For the removal rate, the samples were weighed 3 times: T0 (before induction), T1 (after induction) and T2 (after removal). Morphology evaluation of the residual dentin surface was performed by SEM. Data normality was verified by Shapiro-Wilk test (p ≥ 0.240). T-test for independent samples was applied to evaluate the removal rate. A significance level of 5% was adopted. G2 provided lower removal rate than G1 (G1: 3.68 mg and G2 = 2.26 mg). SEM images showed different morphological characteristics between the groups. G2 showed absent of smear layer, while G1 showed a visible smear layer over the surface. We concluded that ultrasound device provides minimally invasive removal with residual dentin exhibiting open dentin tubules and no smear layer formation and no bacteria, which infer the removal of the infected tissue.
Topics: Animals; Cattle; Dental Caries; Dental Caries Susceptibility; Dentin; Microscopy, Electron, Scanning; Smear Layer
PubMed: 35262554
DOI: 10.1590/0103-6440202203878 -
Journal of Natural Products Feb 2022To enable the further exploration of structure-activity relationships (SARs) of proanthocyanidins (PACs) with dentin biomodification abilities, was selected for...
To enable the further exploration of structure-activity relationships (SARs) of proanthocyanidins (PACs) with dentin biomodification abilities, was selected for scaled-up purification of mixed A-/B-type, medium-size PAC oligomers. Sequential purification by centrifugal partition chromatography (CPC), Sephadex LH-20, and semiprep HPLC chromatography yielded four underivatized tetrameric (-) and two pentameric (-) PACs. Their unambiguous structural characterization involved extensive spectral and chemical degradation approaches to show that epicatechin units are connected by plant-specific combinations of doubly linked A- and singly linked B-type interflavanyl bonds. The biomechanical properties (via dynamic mechanical analysis) and physicochemical structure (via infrared spectroscopy) were assessed to evaluate the biomodification potency of PAC-treated collagen in a preclinical dentin model. This study revealed that (4→8) versus (4→6) bonds in PAC interflavan linkages have limited influence on biomechanical outcomes of dentin. By exhibiting a 25-fold increase in the complex modulus of treated dentin compared to control, aesculitannin E () was found to be the most potent PAC known to date for enhancing the mechanical properties of dentin in this preclinical model.
Topics: Catechin; Cinnamomum zeylanicum; Dentin; Plant Bark; Proanthocyanidins
PubMed: 35107279
DOI: 10.1021/acs.jnatprod.1c00972 -
Journal of Applied Oral Science :... 2023Irrigation solutions might affect dentin surface characteristics and, consequently, endodontic sealers adhesion. This study analyzed the effect of different final...
Irrigation solutions might affect dentin surface characteristics and, consequently, endodontic sealers adhesion. This study analyzed the effect of different final irrigation protocols on push-out bond strength (BS) of AH Plus to dentin seven days and 20 months after obturation. Scanning electron micrographs were obtained from the dentin surface of one sample/group after final irrigation. Canals of bovine incisors were instrumented and received final irrigation with (n=21): G1 - 2.5% sodium hypochlorite (NaOCl) + distilled water; G2 - 2.5% NaOCl + 17% EDTA; G3 - 2.5% NaOCl + 17% EDTA + 2.5% NaOCl; G4 - 2.5% NaOCl + 17% EDTA + 2% chlorhexidine (CHX); G5 - mixture 5% NaOCl + 18% etidronate (HEDP); and G6 - mixture 5% NaOCl + 10% tetrasodium EDTA (Na4EDTA). After irrigation, one root/group was split and images were obtained by scanning electron microscopy (SEM). The other 20 roots/group were filled with only AH Plus sealer. Three slices/root were used for push-out assessment seven days and 20 months after obturation. One-way analysis of variance and Tukey (α<0.05) were used to compare the results among experimental groups, and unpaired t-test (α<0.05) was used to compare the results of the same group over time. The photomicrographs showed that, excepting G1, all groups completely removed the smear layer from the samples. In G2 and G4, the opening of the dentin tubules enlarged. In G3, erosion was observed in the peritubular and intertubular dentin. Values of the BS in the seven days were G2=G3=G4=G5>G6=G1 and in the 20 months were G3=G5>G6=G4>G1=G2. G3, G5, and G6 presented values of BS in 20 months similar to the values of seven days (P>0.05). The final irrigation protocols tested produced dentin surfaces with different characteristics. Only G3 and G5 presented high BS values that were stable over time.
Topics: Animals; Cattle; Edetic Acid; Dentin; Root Canal Irrigants; Root Canal Filling Materials; Sodium Hypochlorite; Etidronic Acid; Dental Pulp Cavity; Root Canal Preparation
PubMed: 37255081
DOI: 10.1590/1678-7757-2023-0005