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Nederlands Tijdschrift Voor... Jan 1987
Topics: Dental Pulp Diseases; Dentin; Dentin Permeability; Dentin, Secondary; Humans
PubMed: 3470621
DOI: No ID Found -
Stomatologia 1989This is a review of the literature about the contemporary aspects of microbial permeability of dentin. They are discussed the factors that are responsible for this... (Review)
Review
This is a review of the literature about the contemporary aspects of microbial permeability of dentin. They are discussed the factors that are responsible for this question and analytically: the structure of dentin, the composition of dentin in organic and inorganic ingredients, the response mechanisms of dentin, that is the irritation dentin and sclerotic dentin, the hypermineralized zone under carious lesions, the role of saliva and dentinal fluid, the role of pulp and its microcirculation against the invasion of microbes and, the role of smear layer. Also this article refers to the immunological reaction of the pulp and finally to the role of dentist in the permeability of dentin, because the more conservative is a tooth preparation the less is the permeability of dentin. In conclusion, the microbial permeability of dentin is a very complicated biological phenomenon that needs more study and further investigations.
Topics: Dental Pulp; Dentin; Dentin Permeability; Humans; Saliva; Tooth Permeability
PubMed: 2701201
DOI: No ID Found -
Cryobiology Jun 2023This study focused on the biomechanical properties and microstructural changes in dentin of teeth in different age groups after cryopreserved for different durations....
This study focused on the biomechanical properties and microstructural changes in dentin of teeth in different age groups after cryopreserved for different durations. Ninety third molars from three age groups (youth group, middle-age group, and elderly group), were collected and randomly divided into three groups according to freezing time at -196 °C (7 days, 30 days, and 90 days). Control group was shored at ordinary temperature. After rewarming, the compressive strength and elastic modulus of the dentin were measured with an electronic universal tester. Scanning electron microscopy was used to evaluate the microstructure of dentin after cryopreservation. After cryopreservation, the compressive strength of the teeth in each experimental group was not significantly different from control group. With the increase of freezing time and age, dentin's elastic modulus showed a decreasing trend. There were statistically significances between the control group and freezing 90d group, freezing 7d and 90d group, youth and middle-aged group, youth and elderly group (P < 0.05). Both freezing time and age factors were significant for the elastic modulus of dentin(P<0.05). There was no interaction effect for age and freezing time. In transverse sections of scanning electron microscopy, the dentinal tubule became narrower, partially occluded, and more easily adhered to impurities in the long freezing time and elderly group. In longitudinal sections, with freezing time and age, the inner wall of the dentinal tubules became rough especially in the aged group cryopreserved for 90 days. No significant microcracks exited in any of the longitudinal sections of dentin.
Topics: Humans; Aged; Middle Aged; Adolescent; Infant; Cryopreservation; Dentin; Freezing; Microscopy, Electron, Scanning
PubMed: 37121387
DOI: 10.1016/j.cryobiol.2023.04.002 -
Journal of the Indian Society of... 2010Dentin is the fundamental substrate of restorative dentistry and its properties and characteristics are key determinants of nearly all restorative, preventive and... (Comparative Study)
Comparative Study
UNLABELLED
Dentin is the fundamental substrate of restorative dentistry and its properties and characteristics are key determinants of nearly all restorative, preventive and disease processes of the teeth. The intrinsic permeability of dentin is responsible for permitting bacterial or chemical substances to diffuse across the dentin and irritate the pulpal and periradicular tissues. Improved understanding of the dentin structure and nature will have important consequences for today's dental procedures. The aims of the study were to observe the direction of dentinal tubules, interglobular dentin, incremental lines of dentin and the dead tracts.
MATERIALS AND METHODS
A total of 30 teeth (15 primary and 15 permanent molars), unrestored, noncarious, hypoplastic extracted molars were used. Longitudinal ground sections of teeth were obtained using hard tissue microtome.
RESULTS
Examination of ground sections of the primary teeth dentin showed "s"-shaped curvature in four (26.7%) specimens and a straight course of dentinal tubules in 11 (73.3%) specimens out of 15 teeth examined whereas in permanent teeth, all 15 (100%) specimens showed an "s"-shaped curvature. These results are statistically highly significant (P < 0.001).
CONCLUSION
Dentinal tubules followed an "s"-shaped course in all the 15 (100%) permanent molars and in four (26.7%) primary molars. There was no significant difference in the occurrence of interglobular dentin of primary and permanent molars. But, they were at angles in the primary teeth.
Topics: Dentin; Dentin Permeability; Humans; Microscopy, Polarization; Molar; Tooth, Deciduous
PubMed: 21157048
DOI: 10.4103/0970-4388.73793 -
Lasers in Medical Science May 2015Attrition and wear of tooth surface occur with aging and result in loss of enamel, with exposure and histological changes in dentin. Dealing with attrited teeth and...
Attrition and wear of tooth surface occur with aging and result in loss of enamel, with exposure and histological changes in dentin. Dealing with attrited teeth and restoration of the lost tissue are clinically challenging. The main objective of this study is to characterize the exposed transparent dentin in the occlusal surface of attrited teeth by optical coherence tomography (OCT). Naturally attrited, extracted human teeth with occlusal-transparent dentin were investigated in comparison to sound and carious teeth. The teeth were subjected to OCT imaging and then cross-sectioned and polished. OCT B-scans were compared to light microscopy images of the same cross section. In OCT images, some changes were evident at the transparent dentin in attrited teeth. An OCT attenuation coefficient parameter (μ t) was derived based on the Beer-Lambert law as a function of backscatter signal slope. The mean values of μ t were 1.05 ± 0.3, 2.23 ± 0.4, and 0.61 ± 0.27 mm(-1) for sound, carious, and transparent dentins, respectively. One-way ANOVA with Tukey's post-hoc showed a significant difference between groups (p < 0.05). Physiological changes in transparent dentin that involve deposition of mineral casts in the dentinal tubules lead to lower attenuation of OCT signal. OCT has a potential role to detect transparent dentin on the surface of attrited teeth and can be used in the future as a clinical adjunct tool.
Topics: Dental Caries; Dental Enamel; Dentin; Humans; Tomography, Optical Coherence; Tooth
PubMed: 24532117
DOI: 10.1007/s10103-014-1541-4 -
Journal of Esthetic and Restorative... Oct 2021This study aimed to compare the color and fluorescence of five dentin ceramic systems with human dentin to enhance shade matching.
OBJECTIVES
This study aimed to compare the color and fluorescence of five dentin ceramic systems with human dentin to enhance shade matching.
MATERIALS AND METHODS
Five dentin ceramic systems, including Vita, GC, Creation, Noritake, and Ivoclar in 16 shades, and 12 human dentins, were prepared. The fluorescence and color coordinates were measured at 380-780 nm. A light source including a visible and a ultraviolet (UV) complemented with a geometry 45° illumination and 0° observer was used. The mean minimum difference in color coordinates and fluorescence efficiency was statistically analyzed before and after UV excitation by one-way ANOVA (p < 0.05). Post-hoc multiple comparisons were performed using the LSD test (p < 0.05).
RESULTS
While the fluorescence efficiency of Noritake and Ivoclar ceramics displayed no significant difference with natural dentin, Vita, GC, and Creation ceramics presented a lower fluorescence compared to the natural dentin (p < 0.05). Noritake and Ivoclar had a better color match with human dentin than the other ceramics. Studying the color differences under UV showed that just Creation offers statistically worse performance than the other ceramic.
CONCLUSIONS
The color and fluorescence of the used different brands of dentin ceramic are not the same as the human dentin. However, Noritake and Ivoclar presented the most similarity.
CLINICAL SIGNIFICANCE
Knowledge of ceramic and natural teeth fluorescence is essential for acceptable reproduction of optical properties in esthetic restorations.
Topics: Ceramics; Color; Dental Porcelain; Dentin; Fluorescence; Humans; Materials Testing
PubMed: 34101330
DOI: 10.1111/jerd.12792 -
Monographs in Oral Science 2006Dentine hypersensitivity is a common oral complaint, affecting the teeth of many individuals. The aetiology is multifactorial; however, over recent years the role of... (Review)
Review
Dentine hypersensitivity is a common oral complaint, affecting the teeth of many individuals. The aetiology is multifactorial; however, over recent years the role of erosion has become more and more important. For dentine hypersensitivity to occur, the lesion must first be localised on the tooth surface and then initiated to exposed dentine tubules which are patent to the pulp. The short, sharp pain symptoms are thought to be derived from the hydrodynamic theory of pain. This episodic pain condition is likely to become a more frequent dental complaint in the future due to the increase in longevity of the dentition and the rise in tooth wear. However, conclusive evidence of successful treatment regimens still eludes us despite a multitude of products available for treatment. In explanation, pain studies are notoriously difficult to conduct due to the subjective nature of pain and the complexity of pain assessment. The basic principles of treatment are altering fluid flow in the dentinal tubules with tubule occlusion or modifying or blocking pulpal nerve response, chemically with agents like potassium or physically.
Topics: Dental Materials; Dental Pulp; Dentin; Dentin Sensitivity; Dentinal Fluid; Humans; Pain; Tooth Erosion
PubMed: 16687894
DOI: 10.1159/000093362 -
Monographs in Oral Science 2023Pathology is the science of how a tissue changes during the process of the disease. The pathology is of important knowledge for understanding subsequent treatment... (Review)
Review
Pathology is the science of how a tissue changes during the process of the disease. The pathology is of important knowledge for understanding subsequent treatment concepts of a disease. In the cariology field, pathological features of caries are often presented using tooth sections, whereby the sequence and spread can be monitored. It is optimal to describe such changes using thin undecalcified tooth sections as an overview can be given of both enamel demineralization and pulp-dentine reactions. Also, an optimal understanding is achieved if the clinical status of carious lesion activity is known. Different studies using human teeth have shown the principle changes in progressive stages of carious lesions; the growth of the enamel lesion reflects the growth condition of the cariogenic biofilm. Surprisingly, the pulp (the odontoblast) is aware of the cariogenic stimuli even before mineral alteration has taken place within the dentine. The microorganisms mainly invade the dentine during enamel cavitation. In this chapter, the current improvement of knowledge on advanced carious lesions has been assessed in detail both histologically and radiographically. From a radiographic point of view, well-defined deep and extremely deep carious lesions and their difference are presented. Recent advances in artificial intelligence (AI) in medicine have raised the possibility of increasing the accuracy and speed of histopathological examination techniques. However, the literature involving AI-based histopathological features of hard and soft dentinal tissue pathologic changes is still scarce.
Topics: Humans; Dentin; Artificial Intelligence; Dental Caries Susceptibility; Dental Caries; Dental Pulp
PubMed: 37364550
DOI: 10.1159/000530557 -
Photomedicine and Laser Surgery Jun 2011We have developed a novel technique of utilizing a stainless steel meshwork mask during treatment of dentin with the Er,Cr:YSGG laser. It is the purpose of this study to...
OBJECTIVE
We have developed a novel technique of utilizing a stainless steel meshwork mask during treatment of dentin with the Er,Cr:YSGG laser. It is the purpose of this study to observe the surface modifications produced by this method.
BACKGROUND DATA
Many techniques have been developed to facilitate bonding of various materials to dentin. However, an optimal bond has not yet been achieved.
METHODS
Four teeth ground to dentin were randomly assigned to two groups. Group 1: Er,Cr:YSGG laser treatment; and Group 2: laser treatment while a 100 μm aperture stainless steel mesh was situated over the dentinal surface.
RESULTS
Group 1 samples appeared rugged but relatively flat. Group 2 samples presented a surface with uniformly aligned craters ∼100 μm wide, 150 μm deep.
CONCLUSIONS
Masking the dentinal surface with a stainless steel mesh during laser irradiation produces a surface texture that appears to facilitate mechanical retention.
Topics: Dental Bonding; Dentin; Humans; In Vitro Techniques; Lasers, Solid-State; Low-Level Light Therapy; Microscopy, Electron, Scanning
PubMed: 21214364
DOI: 10.1089/pho.2010.2881 -
Journal of Dentistry Feb 1995The value of the concept of a pulpo-dentinal complex was assessed on human teeth treated according to the ISO test on biological evaluation. The teeth were extracted... (Review)
Review
OBJECTIVES AND METHODS
The value of the concept of a pulpo-dentinal complex was assessed on human teeth treated according to the ISO test on biological evaluation. The teeth were extracted after 1 or 3 months and examined histologically. Biochemical and biological data available from the dental literature were also re-examined.
RESULTS
During the early development of the tooth, pulp and dentine establish close links and form an undivided organ. However, examination of the tissues at later stages of development casts doubt on the validity of such a concept. Major differences are reviewed in this report between the cells (odontoblasts and heterogeneous pulpal cells) and extracellular matrix (collagens, non-collagenic proteins and phospholipids) located either in the odontoblast-dentine area or in the pulp. It seems also that clear-cut differences are detected during inflammatory and repair processes.
CONCLUSION
It is concluded that, although the existence of a dentino-pulpal reaction cannot be denied, the concept of a pulpo-dentinal complex is an oversimplification and should be revisited. This may have implications in the evaluation of restorative treatments and in the design of a tissue repair strategy.
Topics: Adolescent; Adult; Child; Dental Pulp; Dentin; Dentin, Secondary; Extracellular Matrix; Humans; Odontoblasts; Odontogenesis
PubMed: 7876411
DOI: 10.1016/0300-5712(95)90655-2