scholarly journals Macroscopic analysis of dental and periodontal tissues of pig (Sus domesticus) exposed to high temperatures

2017 ◽  
Vol 21 (1) ◽  
pp. 28-34
Author(s):  
Sebastián Medina ◽  
Sandra Henao ◽  
Viviana Muñóz ◽  
Carolina López ◽  
Juan Esteban Gutiérrez ◽  
...  

SUMMARYObjective: To describe the physical changesofmacro-structural dental tissues (enamel,dentin and cement) and periodontal(oral mucous membrane, alveolar compactbone and cancellous alveolar bone) ofdomestic pig (Sus domesticus) expose tohigh temperatures.Materials and methods: This descriptivestudy observed the physical changes in macro-structural dental tissues and periodontalin 25 teeth of domestic pigs subjected tohigh temperatures (200°C, 400°C, 600°C,800°C and 1000°C).Results: Dental and periodontal tissues studiedshow great resistance when subjectedto high temperatures without changing significantlytheir macro-structure. At 200°Cno color changes and cracks appear in theenamel. At 400°C there was an increase ofthe fissure and no separation between thehard tissues, initiating carbonization. At600°C fractures in the dental tissues andbone are most apparent. At 800°C burningof the tissues initiated. At 1000°C there wasno evidence of soft tissue.Conclusions: Macroscopic analysis of theteeth articulated in their alveolar-dentalunits constitutes a experimental model thatssimulates the changes of dental and periodontaltissues expose to high temperature.It is recommended to conduct astudy onhuman teeth in their respective unit articulatedalveolar to determine whether themacro-structural physical changes describedare repeated and can be extrapolated,and which can eventually be used duringthe process of dental identification anddocumentation of the medical legal autopsyused in the case of bodies or human remainsburned, charred and burned.Key words: Forensic dentistry, domesticpig (Sus domesticus), dental and periodontaltissues, temperature exposition, animalmodel.

2017 ◽  
Vol 19 (2) ◽  
Author(s):  
Johanna Aramburo ◽  
Angela Zapata ◽  
Sugey Zúñiga ◽  
Freddy Moreno

Objective: To describe the physical estereomicroscopical changes that occur in dental tissues and materials employed in a conventional endodontic treatment after application of high temperatures. Materials and methods: An in Vitro study was carried out to observe microscopic, structural and physical changes on hard dental tissues (enamel, dentine and cement) and on endodontic materials (gutta-percha Maillefer Dentsply®, endodontical cement based on oxide of zinc-eugenol Eufar®, cement based on epoxic resin Top Seal® Dentsply®, glass ionomer Fuji I® GC America®, silver amalgam GS80® SDI® and composite Point 4® Kerr®) in 124 human teeth, submitted to five temperature ranks (200ºC, 400ºC, 600ºC, 800ºC, 1000ºC). Results: The studied tissues and dental materials presented great resistance to the high temperatures without varying considerably their micro structure, such as that the physical changes (dimensional stability, cracks, pits, fractures, texture, color, carbonization and incineration) can be observed through estereomicrophotographies and can be associated to each specific rank of temperature. Conclusions: Some macrostructural changes of dental tissues and the dental materials occur of specific form in each rank of temperature, and for this reason they can be employed in the comparison before and postmortem during the process of identification of burned or charred corpse and human remains. Key words: Forensic dentistry, human identification, stereomicroscopy, dental materials, high temperatures.


DYNA ◽  
2016 ◽  
Vol 83 (195) ◽  
pp. 34-41 ◽  
Author(s):  
Sebastián Medina ◽  
Liliana Salazar ◽  
Carlos Mejía ◽  
Freddy Moreno

This paper details a cross-sectional, descriptive observational in vitro study of a pseudo-experimental nature that analyzes Electron Microscopy (SEM) by scanning the physical behavior of enamel and dentin calcium hydroxyapatite. The purpose is to describe the separation of these two mineralized dental tissues at the dentin-enamel junction (DEJ) when the teeth are subjected to high temperatures. This study provides scientific evidence that may broaden the discussion on the use of separation of the dentin-enamel junction as a constant and repetitive reliable marker for forensic use (use in forensic sciences) that can contribute to the dental identification process and documentation in a legal medical autopsy, given a situation in which bodies or human remains have been burned, carbonizated or incinerated.


1980 ◽  
Vol 28 (11) ◽  
pp. 1215-1223 ◽  
Author(s):  
H M Wang ◽  
V Nanda ◽  
L G Rao ◽  
A H Melcher ◽  
J N Heersche ◽  
...  

Specific antibodies to porcine gingival type III collagen were raised in sheep. After purification on collagen affinity columns the antibodies were used for immunohistochemical localization of type III collagen in porcine periodontal and dental tissues employing the peroxidase-antiperoxidase (PAP) procedure. The extent of staining of the periodontal tissues was found to approximate the amount of type III collagen measured biochemically. A fairly uniform distribution of type III collagen was observed in the periodontal ligament and gingiva with more intense staining often being associated with blood vessels. A regular pattern of weakly staining fibers could be demonstrated throughout the cementum and in parts of the alveolar bone tissue. In addition, occasional sites in the cementum having a different morphological appearance from the rest of the cementum exhibited bundles of positively stained fibers. Although the bone tissue was essentially unstained, fibers in the endosteal spaces stained strongly. Sharpey's fibers passing from the soft connective tissues into alveolar bone and cementum also stained strongly. Three distinct arrangements of collagen fibers stained by the type III collagen antibodies could be identified: first, a reticular pattern, which was seen at the junction of the gingival epithelium and connective tissue, and in the endosteal spaces and dental pulp; second, a more diffuse pattern of fibers intermingled with type I collagen in the soft connective tissues; and third, a coating of some Sharpey's fibers, having a core believed to be type I collagen, and of fibers in the cementum inclusions.


2017 ◽  
Vol 21 (1) ◽  
pp. 12-21 ◽  
Author(s):  
Johanna Aramburo ◽  
Herney Garzón ◽  
Juán Camilo Rivera ◽  
Sebastián Medina ◽  
Freddy Moreno

SUMMARYObjective: To describe the macroscopicchanges of titanium and fiberglass postscemented in human premolars subjectedto high temperatures for forensic purposes.Materials and methods: An in Vitro experimentalstudy was conducted to observethe macroscopic physical changes of dentaltissues (enamel, dentine and cement), ofmaterials of conventional endodontic use(gutta-percha Wave One® Maillefer Dentsply®, endodontic cement with epoxic resinTop Seal® Maillefer Dentsply®), postscement Relyx TM ARC 3M ESPE®) andof the titanium posts (Tenax® EndodonticPost System Coltene®) and fiberglassposts (Tenax® Fiber Trans Coltene®) in124 human teeth, exposed to five ranks oftemperature 200ºC, 400ºC, 600ºC, 800ºC,1000ºC (three teeth at each temperature).Results: The studied tissues and dentalmaterials used in this study, offer greatresistance to high temperatures, exhibitingconsiderably variation of their macrostructure,in a way that the physical changes(dimensional stability, fissures, cracks,fractures, texture, color, carbonization andincineration) can serve to identify them andto associate such changes to each rank ofspecific temperature.Conclusion: The titanium and fiberglassposts cemented in human premolars offergreat resistance to the action of high tem-peratures. In the same way, they presentspecific changes associated to the dentaltissues that can contribute with the processof identification and medico-legal necropsyof a corpse or burned, incinerated or carbonizedhuman rests.Key words: Forensic dentistry, humanidentification, dental tissues, dental materials,endodontics, high temperatures.


2014 ◽  
Vol 02 (02) ◽  
pp. 084-090
Author(s):  
Krishma Sharda ◽  
Varun Jindal ◽  
Ajay Chhabra ◽  
◽  

Abstract Aim: The present study was done to evaluate and compare the effect of different temperatures (400 C, 800 C and 1000 C) on Composite as post endodontic restoration using Naked eye, Digital camera and Radiovisiography (RVG) in forensic analysis. Methodology: An in vitro study was conducted on 42 human teeth with composite as post endodontic restoration exposed to three temperature ranges: 400°C, 800°C and 1,000°C. Results: Composite material studied in the present research offered great resistance to high temperatures, without exhibiting considerable macrostructure variation, in such a way that physical changes (dimensional stability, fissures, cracks, fractures, texture, color, carbonization and incineration) can be identified and associated to each specific temperature range. Conclusion: Dental tissues and materials offer great resistance to the effect of high temperatures. Moreover, they present specific changes (color, texture, fissures, cracks fractures, fragmentation) which might contribute to the process of identifying a corpse, or burned, incinerated or carbonized human remains.


Author(s):  
M. L. Zimny ◽  
A. C. Haller

During hibernation the ground squirrel is immobile, body temperature reduced and metabolism depressed. Hibernation has been shown to affect dental tissues varying degrees, although not much work has been done in this area. In limited studies, it has been shown that hibernation results in (1) mobilization of bone minerals; (2) deficient dentinogenesis and degeneration of alveolar bone; (3) presence of calculus and tears in the cementum; and (4) aggrevation of caries and pulpal and apical tooth abscesses. The purpose of this investigation was to study the effects of hibernation on dental tissues employing scanning electron microscopy (SEM) and related x-ray analyses.


2021 ◽  
pp. 002203452110199
Author(s):  
Y. Xie ◽  
Q. Tang ◽  
S. Yu ◽  
W. Zheng ◽  
G. Chen ◽  
...  

Orthodontic tooth movement (OTM) depends on periodontal ligament cells (PDLCs) sensing biomechanical stimuli and subsequently releasing signals to initiate alveolar bone remodeling. However, the mechanisms by which PDLCs sense biomechanical stimuli and affect osteoclastic activities are still unclear. This study demonstrates that the core circadian protein aryl hydrocarbon receptor nuclear translocator–like protein 1 (BMAL1) in PDLCs is highly involved in sensing and delivering biomechanical signals. Orthodontic force upregulates BMAL1 expression in periodontal tissues and cultured PDLCs in manners dependent on ERK (extracellular signal–regulated kinase) and AP1 (activator protein 1). Increased BMAL1 expression can enhance secretion of CCL2 (C-C motif chemokine 2) and RANKL (receptor activator of nuclear factor–κB ligand) in PDLCs, which subsequently promotes the recruitment of monocytes that differentiate into osteoclasts. The mechanistic delineation clarifies that AP1 induced by orthodontic force can directly interact with the BMAL1 promoter and activate gene transcription in PDLCs. Localized administration of the ERK phosphorylation inhibitor U0126 or the BMAL1 inhibitor GSK4112 suppressed ERK/AP1/BMAL1 signaling. These treatments dramatically reduced osteoclastic activity in the compression side of a rat orthodontic model, and the OTM rate was almost nonexistent. In summary, our results suggest that force-induced expression of BMAL1 in PDLCs is closely involved in controlling osteoclastic activities during OTM and plays a vital role in alveolar bone remodeling. It could be a useful therapeutic target for accelerating the OTM rate and controlling pathologic bone-remodeling activities.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Hui Yu ◽  
Tianyi Zhang ◽  
Haibin Lu ◽  
Qi Ma ◽  
Dong Zhao ◽  
...  

Abstract Background Granulocyte colony-stimulating factor (G-CSF) is an important immune factor that mediates bone metabolism by regulating the functions of osteoclasts and osteoblasts. Bone loss is a serious and progressive result of periodontitis. However, the mechanisms underlying the effects of G-CSF on periodontal inflammation have yet not been completely elucidated. Here, we examined whether an anti-G-CSF antibody could inhibit bone resorption in a model of experimental periodontitis and investigated the local expression of G-CSF in periodontal tissues. Methods Experimental periodontitis was induced in mice using ligatures. The levels of G-CSF in serum and bone marrow were measured; immunofluorescence was then performed to analyze the localization and expression of G-CSF in periodontal tissues. Mice with periodontitis were administered anti-G-CSF antibody by tail vein injection to assess the inhibition of bone resorption. Three-dimensional reconstruction was performed to measure bone destruction‐related parameters via micro-computed tomography analysis. Immunofluorescence staining was used to investigate the presence of osteocalcin-positive osteoblasts; tartrate-resistant acid phosphatase (TRAP) staining was used to observe osteoclast activity in alveolar bone. Results The level of G-CSF in serum was significantly elevated in mice with periodontitis. Immunofluorescence analyses showed that G-CSF was mostly expressed in the cell membrane of gingival epithelial cells; this expression was enhanced in the periodontitis group. Additionally, systemic administration of anti-G-CSF antibody significantly inhibited alveolar bone resorption, as evidenced by improvements in bone volume/total volume, bone surface area/bone volume, trabecular thickness, trabecular spacing, and trabecular pattern factor values. Immunofluorescence analysis revealed an enhanced number of osteocalcin-positive osteoblasts, while TRAP staining revealed reduction of osteoclast activity. Conclusions G-CSF expression levels were significantly up-regulated in the serum and gingival epithelial cells. Together, anti-G-CSF antibody administration could alleviates alveolar bone resorption, suggesting that G-CSF may be one of the essential immune factors that mediate the bone loss in periodontitis.


2021 ◽  
Vol 22 (2) ◽  
pp. 539
Author(s):  
Yüksel Korkmaz ◽  
Behrus Puladi ◽  
Kerstin Galler ◽  
Peer W. Kämmerer ◽  
Agnes Schröder ◽  
...  

Nitric oxide (NO) binds to soluble guanylyl cyclase (sGC), activates it in a reduced oxidized heme iron state, and generates cyclic Guanosine Monophosphate (cGMP), which results in vasodilatation and inhibition of osteoclast activity. In inflammation, sGC is oxidized and becomes insensitive to NO. NO- and heme-independent activation of sGC requires protein expression of the α1- and β1-subunits. Inflammation of the periodontium induces the resorption of cementum by cementoclasts and the resorption of the alveolar bone by osteoclasts, which can lead to tooth loss. As the presence of sGC in cementoclasts is unknown, we investigated the α1- and β1-subunits of sGC in cementoclasts of healthy and inflamed human periodontium using double immunostaining for CD68 and cathepsin K and compared the findings with those of osteoclasts from the same sections. In comparison to cementoclasts in the healthy periodontium, cementoclasts under inflammatory conditions showed a decreased staining intensity for both α1- and β1-subunits of sGC, indicating reduced protein expression of these subunits. Therefore, pharmacological activation of sGC in inflamed periodontal tissues in an NO- and heme-independent manner could be considered as a new treatment strategy to inhibit cementum resorption.


2009 ◽  
Vol 88 (8) ◽  
pp. 752-756 ◽  
Author(s):  
A. Miyagawa ◽  
M. Chiba ◽  
H. Hayashi ◽  
K. Igarashi

During orthodontic tooth movement, the activation of the vascular system in the compressed periodontal ligament (PDL) is an indispensable process in tissue remodeling. We hypothesized that compressive force would induce angiogenesis of PDL through the production of vascular endothelial growth factor (VEGF). We examined the localization of VEGF in rat periodontal tissues during experimental tooth movement in vivo, and the effects of continuous compressive force on VEGF production and angiogenic activity in human PDL cells in vitro. PDL cells adjacent to hyalinized tissue and alveolar bone on the compressive side showed marked VEGF immunoreactivity. VEGF mRNA expression and production in PDL cells increased, and conditioned medium stimulated tube formation. These results indicate that continuous compressive force enhances VEGF production and angiogenic activity in PDL cells, which may contribute to periodontal remodeling, including angiogenesis, during orthodontic tooth movement.


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