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International Endodontic Journal Sep 1981
Topics: Dentin; Humans; Odontoblasts
PubMed: 6949875
DOI: 10.1111/j.1365-2591.1981.tb01087.x -
Biomimetic remineralization of human dentine via a "bottom-up" approach inspired by nacre formation.Materials Science & Engineering. C,... Apr 2022Nacre exhibited noticeable similarities in fundamental material buildup and biological characteristics with tooth hard tissue, so the present study aims to achieve...
Nacre exhibited noticeable similarities in fundamental material buildup and biological characteristics with tooth hard tissue, so the present study aims to achieve bionic dentine remineralization by duplicating nacre's "bottom-up" assembly concept. Inspired by nacre's mineralization mechanism, the present project starts to synthesize a "seawater-like" mineralizing precursor medium, then monitor its in vitro dentinal tubules occlusion effect, acid-resistant stability, the "fingerprint" dynamic components change in real time on in vitro sensitive tooth model as well as its in vitro cellular biological response towards human dental pulp stem cells. For the further exploration, a single-layer fibrillar collagen model was established to simulate the exposed collagen of demineralized dentine to appraise its intrafibrillar mineralization effect. The results demonstrated that the application of "seawater-like" mineralizing precursor medium effectively occluded dentinal tubules, reduced dentine permeability, increased surface microhardness, provided certain acid-resistant stability and possessed favorable in-vitro biocompatibility. In addition, the dynamic procedure of hierarchical intrafibrillar nanocrystalline assembly was observed, which offered a clue to uncover its remineralizing mechanism. It is attainable to realize the biomimetic remineralization of human dentine via the "bottom-up" concept inspired by nacre structure duplication, suggesting great potential for providing dentists a therapeutic strategy to counter dentine hypersensitivity in the future.
Topics: Biomimetics; Dentin; Humans; Nacre; Tooth; Tooth Remineralization
PubMed: 35577686
DOI: 10.1016/j.msec.2022.112670 -
International Endodontic Journal Aug 2021To introduce a methodology designed to simultaneously visualize dental ultrastructures, including cellular and soft tissue components, by utilizing phosphotungstic acid...
AIM
To introduce a methodology designed to simultaneously visualize dental ultrastructures, including cellular and soft tissue components, by utilizing phosphotungstic acid (PTA) as a contrast-enhancement agent.
METHODOLOGY
Sound third molars were collected from healthy human adults and fixed in 4% buffered paraformaldehyde. To evaluate the impact of PTA in concentrations of 0.3%, 0.7% and 1% on dental soft and hard tissues for CT imaging, cementum and dentine-pulp sections were cut, dehydrated and stained with immersion periods of 12, 24 h, 2 days or 5 days. The samples were scanned in a high-resolution nano-CT device using pixel sizes down to 0.5 µm to examine both the cementum and pulpal regions.
RESULTS
Dental cementum and periodontium as well as odontoblasts and predentine were made visible through PTA staining in high-resolution three-dimensional nano-CT scans. Different segments of the tooth required different staining protocols. The thickness of the cementum could be computed over the length of the tooth once it was made visible by the PTA-enhanced contrast, and the attached soft tissue components of the interior of the tooth could be shown on the dentine-pulp interface in greater detail. Three-dimensional illustrations allowed a histology-like visualization of the sections in all orientations with a single scan and easy sample preparation. The segmentation of the sigmoidal dentinal tubules and the surrounding dentine allowed a three-dimensional investigation and quantitative of the dentine composition, such as the tubular lumen or the ratio of the tubular lumen area to the dentinal surface.
CONCLUSION
The staining protocol made it possible to visualize hard tissues along with cellular layers and soft tissues in teeth using a laboratory-based nano-CT technique. The protocol depended on both tissue type and size. This methodology offers enhanced possibilities for the concomitant visualization of soft and hard dental tissues.
Topics: Adult; Dental Pulp; Dentin; Humans; Odontoblasts
PubMed: 33829522
DOI: 10.1111/iej.13527 -
Quintessence International (Berlin,... Feb 1990The most conservative cavity preparation, which takes full advantage of chemically adhesive composite resin, involves removal of only the infected outer carious dentin...
The most conservative cavity preparation, which takes full advantage of chemically adhesive composite resin, involves removal of only the infected outer carious dentin that is stainable by the caries detector. This preparation exposes in the cavity floor either the turbid layer at the top of the inner carious dentin or the underlying transparent layer. Examination by scanning electron microscope revealed that etching the cavity floor demineralized the intertubular dentinal surface slightly and produced tapered, cylindrical holes or ring-shaped holes at the dentinal tubule apertures of the turbid or transparent layer, respectively. The holes were blind with solid floors of intratubular crystal deposits of the transparent layer, suggesting that etching increases permeability little. Placement of the adhesive resin on the etched cavity floors produced a resin-impregnated dentinal layer and tapered, cylindrical or tubular-shaped resin tags, which apparently improved the bond and tubule aperture seal.
Topics: Acid Etching, Dental; Dental Bonding; Dental Caries; Dental Cavity Preparation; Dentin; Dentin Permeability; Humans
PubMed: 2197664
DOI: No ID Found -
Medical Hypotheses Oct 2009Dental disease affects human health and the quality of life of millions worldwide. Tooth decay (caries) and diseases of the dental pulp result in loss of tooth vitality...
Dental disease affects human health and the quality of life of millions worldwide. Tooth decay (caries) and diseases of the dental pulp result in loss of tooth vitality and function requiring invasive treatment to restore the tooth to health. "Therapeutic" low intensity pulsed ultrasound has been shown to accelerate bone fracture healing indicating that ultrasound may be used as a tool to facilitate hard tissue regeneration. We have shown recently that low frequency ultrasound is able to exert biological effects on odontoblast-like cells. In this paper, we postulate that low frequency, low intensity ultrasound may stimulate endogenous coronal tooth repair by stimulating dentine formation from existing odontoblasts or by activating dental pulp stem cells to differentiate into new reparative dentine-producing cells. Ultrasound therapy promoting dentine formation and repair may also have the potential benefit of alleviating dentine hypersensitivity by inducing occlusion of dentinal tubules. It is envisaged that therapeutic ultrasound may be used in future to facilitate dental tissue engineering and stem cell therapy applications for dental tissue regeneration. Further research is warranted in this clinically important area and we envisage that novel strategies in dental therapy will be realised that may ultimately lead to the development of novel non-invasive, multifunctional ultrasound devices for dental diagnostics, repair and regeneration.
Topics: Dentin; Humans; Models, Biological; Tooth Diseases; Ultrasonic Therapy
PubMed: 19553029
DOI: 10.1016/j.mehy.2009.05.032 -
Scanning electron microscopy evaluation of the link between a new dentinal desensitizer and dentine.Minerva Stomatologica Sep 2003The purpose of this study was to evaluate the interaction of a novel dentinal desensitizer Twin Pro with enamel-dentinal adhesive preparations or filling materials and... (Review)
Review
AIM
The purpose of this study was to evaluate the interaction of a novel dentinal desensitizer Twin Pro with enamel-dentinal adhesive preparations or filling materials and dentine using scanning electron microscopy (SEM) technology.
METHODS
Black's I class cavities were drilled extracted molar teeth free of caries or fissures, and the cavities disinfected. The specimens were divided into 4 groups of 2 teeth each treated as follows: Group A: Twin Pro, fluid (Tetric-Flow Vivadent) and micro-hybrid (Tetric-Ceram Vivadent) composites placed on the etched (Liner Bond 2V Clearfil) cavities. Group B: Twin Pro, PQ1-Ultradent loaded Primer-Bonding plus fluid and micro-hybrid composites applied to the acid-etched (37% orthophosphoric acid) cavities. Group C: Twin Pro plus Silver amalgam alloy (Phasealloy- Sybram Kerr). Group D (control group): self-etching primer plus fluid and micro-hybrid composite. Specimens were investigated by SEM.
RESULTS
The results obtained in all groups show that the application of Twin Pro does not alter the adhesiveness of the restorative composite materials to the dental wall. In fact the desensitizer and the adhesive layers are indistinguishable at SEM observation, and well adherent to the dentinal surface of the cavities.
CONCLUSION
The results of SEM investigations show that Twin Pro does not decrease the adhesion of restorative materials to the tooth surface, as it establishes an efficient interconnection with the different materials used, and it forms a uniform layer covering and occluding dentine tubules, and this might constitute an efficacious sealing of dentinal tubules which possibly contribute to decrease dentinal sensitivity to environmental nociceptive stimuli.
Topics: Acrylic Resins; Bicuspid; Composite Resins; Dental Amalgam; Dental Bonding; Dental Cavity Lining; Dental Pulp; Dentin; Dentin Sensitivity; Humans; In Vitro Techniques; Microscopy, Electron, Scanning; Polyurethanes; Solutions; Tissue Adhesions
PubMed: 14608247
DOI: No ID Found -
International Endodontic Journal Jan 1990This study was carried out to investigate the presence and types of bacteria invading the deep layers (0.5-2.0 mm from the surface of the root canal wall) of infected...
This study was carried out to investigate the presence and types of bacteria invading the deep layers (0.5-2.0 mm from the surface of the root canal wall) of infected dentine of human root canals by sampling with an anaerobic glove box system the split surfaces of eight freshly extracted teeth. More bacteria were recovered after incubation in an anaerobic glove box than after aerobic incubation in air with 30 per cent CO2. Out of 256 predominant bacterial isolated, 205 isolates (80 per cent) were obligate anaerobes. These findings suggest that the environment of deep layers of endodontic dentinal lesions is anaerobic and favours the growth of anaerobes. Among the obligate anaerobic isolates, strains belonging to Lactobacillus (30 per cent) and Streptococcus (13 per cent) were predominant, followed by Propionibacterium (9 per cent). No strains of obligate anaerobic Gram-negative rods were isolated. The microflora of deep layers of infected root dentine is somewhat similar to that of the deep layers of carious lesions in coronal dentine.
Topics: Bacteria, Anaerobic; Colony Count, Microbial; Dental Pulp Cavity; Dentin; Humans; Tooth Root
PubMed: 2391177
DOI: 10.1111/j.1365-2591.1990.tb00798.x -
Current Opinion in Periodontology 1994Dentine hypersensitivity is a common painful condition of the teeth for which little is known of the etiology and predisposing factors. This tends to compromise... (Review)
Review
Dentine hypersensitivity is a common painful condition of the teeth for which little is known of the etiology and predisposing factors. This tends to compromise management, and recurrence of the condition is frequent. Abrasive and erosive factors, by their effects on enamel and gingiva, are important in localizing sites of exposed dentine. Erosive agents are probably responsible for initiating sensitivity by opening dentinal tubules. Management should not only be treatment based. First, a differential diagnosis should be considered. Then, etiologic and predisposing factors should be identified and where possible removed, reduced, or modified. Treatments are largely aimed at blocking the hydrodynamic mechanism for stimulus transmission across dentine by occluding dentinal tubules. There is a need for further research into understanding the condition itself, its etiology, and the mode of action of the large number of varied but apparently effective therapeutic agents.
Topics: Dentin; Dentin Sensitivity; Humans; Hydrostatic Pressure
PubMed: 8032468
DOI: No ID Found -
American Journal of Physical... Jan 2021The histological identification of interglobular dentine (IGD) in archeological human remains with macroscopic evidence of rickets has opened a promising new avenue for...
The histological identification of interglobular dentine (IGD) in archeological human remains with macroscopic evidence of rickets has opened a promising new avenue for the investigation of metabolic disease in the past. Recent paleopathological studies have shown that histological analysis of archeological human teeth may allow the identification of periods of vitamin D deficiency occurring within very narrow developmental windows, yielding new information on the seasonality or even maternal-fetal transmission of this disease. However, currently available techniques for recording IGD rely on subjective scoring systems or visual estimations, potentially leaving them open to inter and intra-observer error and rendering comparisons of datasets difficult. Here we describe a new imaging protocol that utilizes open access software and may yield more objective and quantitative data on the amount of IGD present within a dentinal region of interest. We demonstrate that grayscale histograms in FIJI®/ImageJ® might be used to provide less subjective estimates of the percentage of a region of interest affected by IGD. Application of this technique may enable more accurate comparison of datasets between researchers.
Topics: Anthropology, Physical; Dentin; Histological Techniques; Humans; Image Processing, Computer-Assisted; Software; Tooth; Vitamin D Deficiency
PubMed: 32914865
DOI: 10.1002/ajpa.24143 -
Caries Research 1990In this paper the in vitro remineralization of human dentine with 0, 0.5, 2 and 10 ppm F in the remineralization solution is presented and analyzed by microradiography.... (Comparative Study)
Comparative Study
In this paper the in vitro remineralization of human dentine with 0, 0.5, 2 and 10 ppm F in the remineralization solution is presented and analyzed by microradiography. Furthermore, the remineralization data of human and bovine dentine are quantitatively compared. The main results of this paper are: (1) the efficacy of human (and bovine) remineralization is about proportional to the square root of the F level in the remineralizing solution, and (2) the amount of mineral effectively deposited in the dentine is most likely controlled by the diffusion of fluoride into the tissue. This study shows furthermore that although numerical differences exist in the remineralization of human and bovine dentine, the general remineralization behaviour is quite similar. The presence of F- in the parts per million range is essential for the remineralization efficacy in vitro and also for the 'overremineralization' of the outer dentine surface.
Topics: Adolescent; Animals; Cattle; Child; Dental Caries; Dentin; Fluorides; Humans; Tooth Remineralization
PubMed: 2289224
DOI: 10.1159/000261304