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Journal of Comparative Pathology May 2021Histopathological changes in tooth structures in dogs with calculus have not been described. The aim of this study was to evaluate the frequency of various...
Histopathological changes in tooth structures in dogs with calculus have not been described. The aim of this study was to evaluate the frequency of various histopathological changes in the dentine of teeth that had been surgically extracted from dogs with calculus. Data including breed, sex, age, reason for tooth extraction and dental history were obtained for each animal. A total of 158 teeth (45 incisors, 31 canines, 35 premolars and 47 molars) with calculus were extracted from 74 dogs of various ages and breeds. The teeth were decalcified, processed in paraffin wax and stained with haematoxylin and eosin for histopathological analysis. Of the 158 analysed teeth, 71 had dentinal changes, including 45 with external resorption cavities, 11 with osteodentine, six with internal resorption cavities, four with tertiary dentine, four with dentinal degeneration or fragmentation, and one with predentine degeneration or fragmentation. Canine teeth were the least commonly affected. Areas of dentinal degeneration or fragmentation unrelated to resorption cavities were only seen in the incisor and molar teeth. Dentinal changes and their frequencies were similar among the incisor, premolar and molar teeth. The presence or extension of dental calculus was not associated with the type or frequency of dentinal changes.
Topics: Animals; Dental Calculus; Dentin; Dog Diseases; Dogs; Tooth
PubMed: 34119235
DOI: 10.1016/j.jcpa.2021.03.004 -
Nederlands Tijdschrift Voor... Feb 2017Many people sometimes experience pain when they inhale breath across the cingula, or sensitivity and/or pain when they eat ice cream, for example. In some cases,... (Review)
Review
Many people sometimes experience pain when they inhale breath across the cingula, or sensitivity and/or pain when they eat ice cream, for example. In some cases, however, this can become seriously unpleasant. In those cases, one can speak of dentine hypersensitivity. In Europe, an average of 27% of the population suffers from this. Dentine hypersensitivity is characterised by a short, sharp pain reaction after a warm or cold sensation. The external sensation causes an accelerated or converse flow of fluid in the dentinal tubules that excites the extremities of the nerve cells, which results in the sensation pain. For the external sensation, it is necessary that the cingula are exposed and the dentinal tubules are open. Dentine hypersensitivity is diagnosed after other possibilities have been eliminated.
Topics: Dentin; Dentin Sensitivity; Humans; Prevalence; Preventive Dentistry
PubMed: 28186512
DOI: 10.5177/ntvt.2017.02.16235 -
Collegium Antropologicum Sep 2008The aims of this study were threefold: (1) to characterize and quantify the number, diameter and surface area of exposed dentinal tubules on the cross section of the...
The aims of this study were threefold: (1) to characterize and quantify the number, diameter and surface area of exposed dentinal tubules on the cross section of the human coronal dentin; (2) to determine if any such differences in these properties arise in relation to the distance from the dentinoenamel junction; and (3) to evaluate whether such differences can influence dentin hybridization. To accomplish these aims, scanning electron microscopy comparative observation was carried out on 60 prepared human premolars, which were divided into three groups of 20 samples each. The three sample groups were cut as follows: (1) in the central fissure region, one millimeter from the enamel-dentine junction; (2) halfway between the enamel-dentine junction and the pulp; and (3) one millimeter from the roof of the pulp chamber. Using one-way analysis of variance (one-way ANOVA) and a regression linear model, the data enumerated below were obtained. First, the mean number of the tubule openings was 19600/mm2 on the first level, 32400/mm2 on the second and 42300/mm2 on the third. The mean tubule diameter on the first level was 0.67 microm, 1.52 microm on the second and 2.58 microm on the third. Finally, exposed tubules on the first level occupied 2.79% of of total dentinal surface area, 23.90% on the second, and 87.78% on the third level. Therefore, significant statistical differences (p < 0.01) between all three groups of the specimens for all three properties were observed, as well as positive correlation between the dentin depth and each of these properties. This indicates that the dentin structural variety, which ultimately determines adhesion to dentine, involves a complex interaction between biological material (dentin) and the particular adhesion system applied.
Topics: Adolescent; Dental Bonding; Dental Cements; Dental Enamel; Dental Pulp; Dentin; Dentin-Bonding Agents; Humans; Microscopy, Electron, Scanning; Young Adult
PubMed: 18982768
DOI: No ID Found -
Zhonghua Kou Qiang Yi Xue Za Zhi =... May 2005To examine, in vitro study, the ultrastructure of resin-infiltrated sclerotic dentine following the application of a two-step self-etching dentin adhesive.
OBJECTIVE
To examine, in vitro study, the ultrastructure of resin-infiltrated sclerotic dentine following the application of a two-step self-etching dentin adhesive.
METHODS
Non-carious, natural cervical sclerotic lesions were bonded using Contax (DMG Hamburg, Germany), a self-etching dentin adhesive. Artificially prepared wedge-shaped lesions were also made in sound bicuspids and bonded using the same adhesive as controls. By SEM examination, the morphological change of the dentin surface treated by Contax Primer, and the hybrid layer and resin tag in the dentin-resin interface were studied.
RESULTS
Most dentinal tubules were occluded by rod-like sclerotic casts in the sclerotic dentin surface. Both hybrid layer and resin tag were observed in sclerotic dentin. The hybrid layer was almost similar to that in the sound dentin, but the resin tags were shorter than those in controls.
CONCLUSIONS
Bonding to sclerotic dentin is different from sound dentin and may be compromised by occluded dentin tubules. Based on the present ultrastructural features of hybrid layer and resin tags, the Contax, a self-etching dentin adhesive with a low pH value primer, may have some bonding efficacy to sclerotic dentin.
Topics: Dentin; Dentin-Bonding Agents; Humans; Microscopy, Electron, Scanning; Tooth Cervix
PubMed: 15938888
DOI: No ID Found -
Collegium Antropologicum Sep 2008The aim of this study is to investigate the influence of different etching times on demineralized dentin surface morphology using scanning electron microscopy and...
The aim of this study is to investigate the influence of different etching times on demineralized dentin surface morphology using scanning electron microscopy and qualitative line microanalysis of chemical structure. Two sample groups, consisting of 30 first premolar teeth in each group, were established. Teeth were cut at the half-distance between the enamel-dentin junction and the pulp. The first group of specimens was etched for 10 seconds and the second group for 30 seconds. 37% ortophosphoric acid was used. SEM (scanning electron microscopy) was utilized to observe the following parameters: number and diameter of dentinal tubules, dentinal and intertubular dentinal surface percentage, appearance of the dentin surface porous zone containing smear layer and demineralized residual collagen particles with dentin demineralization products in acid globules, and dissolved peritubular dentin cuff. After calculating measurements of central tendency (X,C, Mo, SD), Kolmogorov-Smirnov and Student t-test were performed to confirm the quantitative results, and the chi2-test was run to produce qualitative data. In contrast to the 10-second etching time, the increased etching time of 30 seconds resulted in the following findings: (1) an increased number of dentinal tubules (p < 0.05), (2) an increase in dentinal tubule diameter (p < 0.05), (3) an increase in dentinal tubule surface percentage (p < 0.001), (4) a decrease in intertubular dentinal surface percentage (p < 0.001), (5) appearance of dentin surface porous zone containing smear layer and demineralized residual collagen particles with dentin demineralization products in acid globules (p < 0.001), and (6) completely dissolved peritubular dentin cuff (p <0.001). Therefore, different etching times using the same phosphoric acid concentration result in different morphological changes in demineralized dentin surface. Moreover, based on a comparison with current studies, prolonged etching time causes morphological changes to dentin surface. Such changes, have, in turn, negative effects on the dentin hybridization process.
Topics: Acid Etching, Dental; Adolescent; Dentin; Humans; Microscopy, Electron, Scanning; Phosphoric Acids; Time Factors; Young Adult
PubMed: 18982767
DOI: No ID Found -
Scientific Reports Feb 2023The occlusion of dentinal tubules has become a rapid and effective method for treating dentin hypersensitivity. Accurate evaluation of dentin occlusion is critical to...
The occlusion of dentinal tubules has become a rapid and effective method for treating dentin hypersensitivity. Accurate evaluation of dentin occlusion is critical to illustrate the efficacy of oral care products and to optimize dental therapy in the clinics, which is limited by the conventional two-dimensional (2-D) characterization methods. Here, we demonstrate the visualization of the dentin occlusion via three-dimensional (3-D) characterization using a focused ion beam-scanning electron microscopy (FIB-SEM) tomography. Using the "Slice and View" approach, the material used for occluding dentin tubules is imaged with a very high-resolution voxel (10 nm × 10 nm × 20 nm) from 2-D SEM images and then reconstructed into a 3-D volume, which presents the mode of action of toothpaste for treating dentin hypersensitivity. Meanwhile, quantitative analysis of the depth of occlusion is successfully obtained. This work validates the feasibility of FIB-SEM tomography in the analysis of dentin occlusion within the complicated networks of dentine tubules at the nanoscale, and provides a novel approach to facilitate the research and development of oral care products.
Topics: Humans; Dentin; Dentin Sensitivity; Imaging, Three-Dimensional; Microscopy, Electron, Scanning; Dentin Desensitizing Agents
PubMed: 36755136
DOI: 10.1038/s41598-023-29155-1 -
Scanning Microscopy Jun 1987This study was performed to gain better insight into the mechanisms involved in carious destruction of human dentin by Streptococcus mutans. In particular, bacterial...
This study was performed to gain better insight into the mechanisms involved in carious destruction of human dentin by Streptococcus mutans. In particular, bacterial colonization of dentin surfaces and bacterial invasion in dentin were studied. Streptococcus mutans (S. mutans), strain NCTC 10449, was grown on sterile dentin blocks in a 10% CO2 atmosphere at 37 degrees C. After 72, 120, 144 and 288 h of incubation the specimens were processed for scanning electron microscopic examination. The colonization of the dentinal surface progressed slowly and was nearly complete after 288 h. Invasion of S. mutans into the dentinal tubules was found occasionally and was limited to the initial 5 micron of the tubular lumen. The acid metabolites produced by S. mutans, caused lesions of the dentinal structures in the close proximity of the bacteria. From the results of this in vitro study it appears that carious destruction of exposed dentinal surfaces by S. mutans mainly occurs at the exposed dentin after it has been colonized by bacteria. Destruction of the deeper dentinal layers by bacteria invading the dentinal tubules may play a less important role. However, in the few cases where S. mutans invaded the dentinal tubules, rapid destruction of the peritubular dentin sheath occurred. In addition, the possibility remains that acid metabolites produced by S. mutans diffuse into the dentinal tubules and cause tissue damage in the deeper parts of the dentin.
Topics: Dental Caries; Dentin; Humans; Microscopy, Electron, Scanning; Streptococcal Infections; Streptococcus mutans
PubMed: 3616564
DOI: No ID Found -
Archives of Oral Biology 1994Hypersensitive dentine responds to normal changes in touch or temperature with abnormal pain sensations. This paper reviews studies that have shown dynamic changes in... (Review)
Review
Hypersensitive dentine responds to normal changes in touch or temperature with abnormal pain sensations. This paper reviews studies that have shown dynamic changes in sensory nerve structure, cytochemistry and location after tooth injury, suggesting that those changes contribute to dentine hypersensitivity. Nerve fibres containing calcitonin gene-related peptide (CGRP) are the main type of sensory fibre to innervate dentine. Evidence that many of those dentinal nerve endings originate from small myelinated fibres is presented here. The location of CGRP nerve terminals correlates with the pulpal gradients of nerve growth factor that have been demonstrated in normal teeth by in situ hybridization histochemistry. When shallow cavities are drilled into the outer dentine of rat molars a five-to-eight-fold increase in pulpal nerve growth factor precedes the extensive structural changes in the sensory nerve reactions eventually subside if healing occurs, but both continue if inflammation continues. Evidence correlating pulpal inflammation with long-term changes in central trigeminal pain pathways is reviewed. There can be extensive neuroplasticity after tooth injury, both within dental pain fibres and in central pain pathways. The timing of those alterations of nerve structure, location, and cytochemistry is consistent with their involvement in mechanisms of dentine hypersensitivity.
Topics: Animals; Dental Pulp; Dentin; Dentin Sensitivity; Humans; Nerve Fibers; Nerve Tissue Proteins; Neuronal Plasticity; Neurons, Afferent; Pulpitis; Tooth Injuries; Trigeminal Nuclei
PubMed: 7702461
DOI: 10.1016/0003-9969(94)90183-x -
Dental Materials : Official Publication... Apr 2018Eight repetitive nucleotide sequences of aspartate-serine-serine (8DSS) derived from dentin phosphoprotein (DPP) has been proved to be a good remineralization agency. In...
OBJECTIVE
Eight repetitive nucleotide sequences of aspartate-serine-serine (8DSS) derived from dentin phosphoprotein (DPP) has been proved to be a good remineralization agency. In this study, 8DSS peptide was employed to induce dentinal tubule occlusion.
METHODS
Dentin samples were acid-etched, and then the samples were coated with 8DSS solution. The binding capacity of 8DSS to acid-etched dentin was tested by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). Subsequently, the 8DSS-treated dentin samples were immersed in artificial saliva for 1, 2 and 4 weeks. After 4 weeks, the remineralized dentin was treated with 6wt% citric acid (pH 1.5) solution for 1min. Dentin permeability measurement and scanning electron microscopy (SEM) were carried out after different periods. Energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) were used to identify the mineral phase of the regenerated minerals.
RESULTS
The results showed that 8DSS had a good binding capacity to the acid-etched dentin, and significantly reduced the dentin permeability by inducing minerals deposited within the dentinal tubules. After 4 weeks, all the dentinal tubules were occluded by large bulk of regenerated minerals, which largely decreased the diameters of the tubules. The regenerated minerals deposited with a deep depth within the dentinal tubules, ensuring an effective occlusion even after an acid challenge. The results of XRD and EDS confirmed that the regenerated minerals were mainly hydroxyapatite (HA).
SIGNIFICANCE
8DSS peptide induced strong dentinal tubule occlusion. 8DSS have a great potential to be used in the treatment of dentin hypersensitivity in the future.
Topics: Acid Etching, Dental; Dentin; In Vitro Techniques; Materials Testing; Microscopy, Electron, Scanning; Peptides; Saliva, Artificial; Spectroscopy, Fourier Transform Infrared; Surface Properties; X-Ray Diffraction
PubMed: 29395469
DOI: 10.1016/j.dental.2018.01.006 -
Journal of Dental Research Mar 1981The hydrodynamic theory of dentin sensitivity states that a stimulus applied at the orifice of exposed dentinal tubules causes movement of tubular fluid which stimulates...
The hydrodynamic theory of dentin sensitivity states that a stimulus applied at the orifice of exposed dentinal tubules causes movement of tubular fluid which stimulates nerve receptors. The fluid should obey principles of fluid movement through capillary tubes. Any decrease in the functional radius of the dentinal tubules should greatly reduce the rate of fluid flow, thus reducing dentinal sensitivity. The purpose of this study was to evaluate the ability of agents that have been used previously for clinical dentin desensitization to reduce the rate of fluid flow through dentin in vitro. Dentin discs prepared from extracted human third molars were treated with 50% citric acid to remove debris from tubular orifices. After placing the discs in a split chamber device, the rate at which buffer solution could filter across the dentin under 240 cm of water pressure was measured. The occlusal side of the disc was then treated with an agent thought to desensitize dentin to determine if it reduced fluid flow rate. Discs that had more than a 50% reduction in flow rate were examined by scanning electron microscopy to determine if those agents that decreased fluid flow also partially occluded tubular orifices. This in vitro model provided a useful quantitative method for screening a host of preparations that have been used in the past to decrease dentin sensitivity.
Topics: Adolescent; Adult; Dentin; Dentin Sensitivity; Female; Humans; In Vitro Techniques; Male; Pressure; Rheology
PubMed: 6937499
DOI: 10.1177/00220345810600030401