PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Dental Pulp”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

[The expression of hepatocyte growth factor in human dental pulp and dental pulp cells].

PURPOSE: To study the expression of hepatocyte growth factor in the dental pulp cell cultured in vitro and the human's healthy dental pulp. METHODS: The 4th generation dental pulp cell cultured in vitro and the extracted tooth for orthodontic therapy were used as study targets. The gene expressions of HGF and C-MET and the expression of C-METmRNA induced by HGF were detected by RT-PCR technique in dental pulp cell cultured in vitro. The expression of HGF was checked by immunohistochemical method in both dental pulp tissue and dental pulp cell cultured in vitro. SPSS10.0 software package was used for SNK-q test. RESULTS: HGFmRNA and C-METmRNA could be detected in dental pulp cell cultured in vitro by real-time reserve transcriptase-polymerase chain reaction. HGF up regulated the expression of C-METmRNA. HGF was positively expressed in the cytoplasms of the dental pulp cell cultured in vitro whereas weak expression was seen in the odontoblast layer and vascular endothelium of the dental pulp tissue. CONCLUSION: HGF expresses by dental pulp cell cultured in vitro and dental pulp tissue of ex vivo healthy teeth.

Cells, Cultured↗

Vascular and cellular responses to pro-inflammatory stimuli in rat dental pulp.

Dental pulp reactivity to various pro-inflammatory stimuli was independently evaluated in rats in terms of a vascular permeability increase and leukocyte recruitment. Substance P, calcitonin-gene related peptide (CGRP) and prostaglandin E(2) (in the picomol range) were applied to the exposed pulp from anesthetised animals and the plasma extravasation measured by the Evans blue content in the tissue following 10 min of administration. Leukocyte recruitment was evaluated morphometrically by counting the cell number present in serial sections of 1:3 4 microm pulp tissue 6 h after bacterial endotoxin (LPS; 0.06-1.2 microg/site) administration. Increase in pulp vascular permeability and cellular recruitment due to the injection of mentioned mediators in the skin or LPS in the peritoneal cavity were used as positive controls. Increase in vascular permeability in the pulp occurred in the same dose-range as observed in the skin, being CGRP the most active substance in both cases. However, it was necessary a higher dose of LPS (1.2 microg) to induce a similar cell recruitment in the pulp as that observed in the rat peritoneal cavity (0.3 microg). These data indicate that dental pulp reactivity presents the same pattern of increase in vascular permeability to other tissues in the rat, being CGRP the most potent mediator in this respect. In addition, they suggest the presence of CGRP receptors in the dental pulp. However, an adequate leukocyte recruitment response to bacterial endotoxin was not mounted, suggesting a deficiency in adhesion molecules in blood vessels in the rat dental pulp.

Analysis of Variance↗

Gene expression of bone matrix proteins in a calcified tissue appeared in subcutaneously transplanted rat dental pulp.

Dental pulp self-mineralizes or induces calcified tissue formation, when it is subcutaneously transplanted. This study aims to clarify the nature and process of this tissue calcification by using histochemical techniques and in situ hybridization methods. The dental pulps of incisors from Sprague-Dawley strain rats were homogeneously transplanted into the subcutaneous tissue of the head of another rat. On the 1st day of transplantation, the mRNAs of type I collagen (COL I) and bone sialoprotein (BSP) were expressed in the transplant. On the 5th to 7th days after transplantation, von Kossa-positive, calcified tissues appeared in the transplanted tissues. The mRNAs of COL I, BSP and osteopontin (OPN) were expressed with the same distributions as those of the von Kossa-positive areas, but those of type II collagen (COL II) and bone morphogenic protein 2 (BMP-2) were not expressed in the transplant. When the cellular incorporation of BrdU was examined after its subcutaneous injection into the animals, positive cells were present in the von Kossa-positive calcified foci as well as in their surrounding areas. These results indicate that the transplanted dental pulp possesses the ability to induce cell proliferation resulting in the synthesis of several bone matrix proteins and the formation of calcified tissue. This may give us an insight into the nature and processes of pulp obliteration, which occurs in a human tooth following an episode of trauma.

Animals↗

Glycosaminoglycans of human dental pulp.

Dental pulps were obtained from sound human permanent molars and premolars. The pulps were treated to remove lipid, protein and nucleic acid and glycosaminoglycans were finally isolated by ethanol precipitation. Electrophoretic examination and CPC-cellulose profiles revealed the presence of hyaluronic acid, dermatan sulphate, chondroitin 4 sulphate and chondroitin 6 sulphate. Hyaluronic acid accounted for only a low percentage of the total glycosaminoglycan content while dermatan sulphate was present in unusually high amounts. Chondroitin 4 and 6 sulphates represented the major glycosaminoglycan fraction.

Chondroitin Sulfates↗

Laser-induced thermal events in empty and pulp-filled dental pulp chambers.

BACKGROUND AND OBJECTIVE: The purpose of this investigation was to evaluate: 1. thermal events during laser irradiation @2.1 microns of the pulp; 2. whether these effects are adequately modeled using an empty pulp chamber/root canal. STUDY DESIGN/MATERIALS AND METHODS: In extracted human teeth, pulpal access was prepared and thermocouples placed 2, 3 mm apical to the center of the irradiation spot. Pulp-filled or empty pulp chambers were irradiated using a Ho:YAG laser: Spot Size: 1 mm; Power: 1, 2, 3.5, 4.5 W; PRR: 5, 12 Hz; DURATION: 10 sec. Thermal measurements were repeated 3x. RESULTS: Thermal trends did not differ significantly and correlated positively with power (P < 0.01), PRR (P < 0.01), irradiation duration (P < 0.05). No significant difference was determined between temperatures in empty and pulp-filled chambers at all parameters at 5 Hz and at 1-2 W at 12 Hz (P < 0.05, 2-tailed Student's t-test). At 12 Hz and > 3.5 W, pulp chamber temperatures exceeded those in pulpal tissue (P < 0.05). CONCLUSION: Pulp tissues must be present to ensure clinical relevance of thermal measurements.

Animals↗

[The characteristics of cultured dental pulp cells and the localization of dental pulp stem cells].

PURPOSE: This study was aimed to investigate the localization of dental pulp stem cells (DPSCs) by comparing the characteristics of cultured dental pulp cells in coronal and root pulp. METHODS: Human dental coronal and root pulp cells were cultured in tissue-explant method, the cell culture successfulness, attachment efficiency, cell viality, morphology, proliferation pattern, and the mineralization ability were observed, the localization of DPSCs was investigated in the functional respect of DPSCs. RESULTS: The human dental root pulp cells have more culture successfulness,more attachment efficiency,more cell viality, more primary characteristics, and stronger induced mineralization ability than that of coronal pulp cells. Root and coronal pulp cells showed same proliferation patterns. CONCLUSIONS: DPSCs may exist in both dental root and coronal pulp, and the density of DPSCs in the root pulp may be higher than the coronal pulp.

Adolescent↗

Expression of intermediate filaments and actins in human dental pulp and embryonic dental papilla.

The localization of different cytoskeletal proteins (keratin, vimentin, desmin, actin, and alpha-smooth muscle actin) was examined by immunohistochemistry in normal human adult dental pulp and compared with dental papilla of tooth germs. Keratin and actin were localized in enamel organ. Vimentin and actin were observed in the dental papilla and in the adult dental pulp. Desmin and alpha-smooth muscle actin were present only in the vessel walls. These data are discussed paying particular attention to the origin and the peculiar functional characters of the dental papilla and pulp.

Actins↗

Expression of bone morphogenetic protein genes in the human dental pulp cells.

Dental pulp has a potential to induce ectopic bone formation, but little is known about its mechanism. We thought that bone morphogenetic proteins (BMPs), members of the transforming growth factor-beta (TGF-beta) superfamily, are involved in the osteoinductive activity of dental pulp. In order to prove this assumption, we constructed a cDNA library from primary culture cells of human dental pulp (HDP cells), and screened the library with previously cloned cDNAs for mouse BMP-2 and -6 as probes. Three distinct cDNA clones encoding human BMP-2, -4 and -6 were isolated. By Northern blot analysis, specific transcripts of the genes of those BMPs were detected in the HDP cells. It was concluded that the BMPs were expressed in a certain population of dental pulp cells and might play some roles in ectopic bone formation by dental pulp.

Adolescent↗

MC3T3-E1-conditioned medium-induced mineralization by clonal rat dental pulp cells.

Dental pulp is thought to participate in supplementary mineralization, such as reparative dentin and pulp stones, but no direct proof of this has been reported. To study this process at a molecular level, we investigated the matrix mineralization of dental pulp using a clonal cell line (RPC-C2A) derived from rat incisor dental pulp. Mineralized nodules in extracellular matrix were formed by RPC-C2A cells cultured in the presence of conditioned medium (CM) from confluent osteoblastic MC3T3-E1 cells. These nodules were stained by the von Kossa method and with alizarin red S and quantified by the measurement of acid-soluble calcium deposition. This CM was most effective when collected 3-6 days after confluency and added at 50% to the culture medium. The CM-treated RPC-C2A cells showed high alkaline phosphatase activity, a high mRNA level of osteocalcin and decreases in the mRNA levels of osteopontin and osteonectin, but undetectable levels of mRNA of dentin sialophosphoprotein by Northern blot analyses. A pan-specific anti-transforming growth factor (TGF)-beta antibody and a soluble form of receptor for bone morphogenetic protein (BMP)-2/-4 did not neutralize the CM-induced mineralization. These results suggest that some soluble factor(s) other than TGF-beta or BMP-2/-4 in the CM from MC3T3-E1 cells cause differentiation of RPC-C2A cells to osteoblast-like cells.

Alkaline Phosphatase↗

Sulfated glycosaminoglycan synthesis and its regulation by transforming growth factor-beta in rat clonal dental pulp cells.

Dental pulps contain sulfated glycosaminoglycans (GAGs), such as chondroitin 4-sulfate (CSA/4CS), dermatan sulfate (CSB/DS), and chondroitin 6-sulfate (CSC/6CS). Sulfated GAGs play important roles in mineralization and collagen fibrillogenesis during primary, secondary, and reparative dentin formations. Transforming growth factor-beta (TGF-beta) is a potent regulator for several extracellular matrix (ECM) components and modulates the proliferation and differentiation. Using rat clonal dental pulp cells (RPC-C2A), we investigated the constituents of GAGs synthesized by the cells and the effect of TGF-beta on their synthesis by measuring the radioactivity of [35S]sulfate incorporated into GAG fractions. Cellulose acetate electrophoresis analysis revealed that RPC-C2A cells synthesized CSA and CSB but not CSC and that 10 ng/ml of TGF-beta increased the production of CSA and CSB in the cell/ECM fraction. Measurement of [35S]sulfate incorporation showed a significant increase in the amount of GAGs by TGF-beta, 1.3-fold CSA, and 1.2-fold CSB in the cell/ECM fraction. In the medium fraction the most secreted GAG was CSA, whereas CSB was stored in the cell/ECM fraction. Secreted CSA in the medium was markedly increased by 10 ng/ml of TGF-beta (1.7-fold). These findings indicate that CSA and CSB are major sulfated GAGs synthesized by RPC-C2A cells and that TGF-beta acts as a stimulator of sulfated GAG synthesis in dental pulp cells.

Animals↗

Pulp capping of dental pulp mechanically exposed to oral microflora: a 1-2 year observation of wound healing in the monkey.

Four adult Rhesus monkeys provided 120 teeth for buccal Class V cavities. Twenty-nine were non-exposed controls and 91 were exposed for 3 intervals. All 120 teeth were capped with a hard set Ca(OH)2 medicament, restored with amalgam, 57 evaluated after 1 year and 63 after 2 years. Of the 91 exposed pulps, 45 showed complete healing, 25 showed pulpal inflammation varying from acute to chronic, 12 showed severe pulpal breakdown and abscess formation and 9 were necrotic. No difference was observed in the healing response between the 3 exposure times. New hard tissue formed at, or subjacent to, the medicament in 77 of 91 exposed pulps with a tunnel defect frequently present, running from the medicament interface to the pulp. This study demonstrates that recurring pulp inflammation observed after 1 & 2 year direct pulp capping, is associated with bacterial contamination.

Animals↗

Soluble matrix from osteoblastic cells induces mineralization by dental pulp cells.

Dental pulp cells have a capacity to differentiate into mineralization-inducing cells. To clarify the molecular mechanism, we established an in vitro mineralization-inducing system by rat clonal dental pulp cell line, RPC-C2A, and tried to purify a mineralization-inducing factor in conditioned medium (CM) from pre-osteoblastic MC3T3-E1 cells. The active factor was impermeable to an ultrafiltration membrane, and sedimented by ultracentrifugation. The sedimented factor was found as a needle-like structure about 1.3 microm in average length as observed by transmission electron microscopy. The factor contained type I collagen, suggesting not a matrix vesicle, but a soluble matrix. The mineralization-inducing activity was also detected in CM from primary culture of rat calvaria (RC) cells. These results suggested that the soluble matrices from osteoblastic cells serve, at least in part, as differentiation-inducing agents.

Animals↗