• Restorative Dentistry and Endodontics
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• v.30 no.3
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• pp.193-203
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• 2005

The induction of the IL-8 and MCP-1 by the stimulation of Substance P and TNF-${\alpha}$ (IL-8 agonist) and the specificity for SP using Spantide (SP antagonist) in the dental pulp tissues was measured quantitatively. In addition, the secretion of the IL-8 in the human dental pulp tissue 36 hrs after the stimulation of SP was observed after the stimulation of SP qualitatively. According to this study the results were as follows: 1. There was the significant IL-8 induction at 36 h after SP (10$^{-4}$M) stimulation of the pulp tissue comparing with the unstimulated dental pulp tissues (p < 0.05) . IL-8 irnmunostaining was weakly detected along the periphery of the pulp tissue after Mock stimulation and IL-8 immunostaining was detected around the fibroblast in the pulp tissue 36h After SP (10$^{-4}$M) stimulation, 2. The secretion of MCP-1 from the dental pulp tissues comparing with Mock stimulation was induced at 36 hrs after TNF-$\alpha$ (40 ng/ml) stimulation, but no induction with SP(10$^{-4}$M) TNF-${\alpha}$ (40 ng/ml) did not induce the IL-8 secretion from the pulp tissue, weak IL-8 imrnunostaining was detected along the periphery of the pulp tissue 3. Spantide (10$^{-5}$M) inhibited IL-8 induction from the pulp tissues 36 h after SP (10$^{-4}$M) stimulation These results suggest that SP significantly induces IL-8 recruiting neutrophils in localized human dental pulp tissue MCP-1 appears to be less involved in the early establishment of pulpal inflammation in response to irritation such as mechanical insult of dentin. SP may have positive relation with the inflammation of the human dental pulp tissues.

• The Journal of the Korean dental association
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• v.56 no.10
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• pp.572-580
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• 2018

Adequate access cavity is the key to achieving endodontic success. The aims of the access cavity can be considered as follows: 1) Creation of a smooth unimpeded pathway for instruments to canal orifices 2) Removal of the entire roof of the pulp chamber in order to inspect the pulp floor, 3) Preservation of natural tooth substance consistent with the above. Recently, contracted endodontic cavities based on minimally invasive endodontics has introduced. This has the benefit of preserving the pericervical dentin more than traditional access cavity with achieving long-term success. However, some studies reported controversial results regarding root canal detection, instrumentation efficacy (noninstrumented canal area, hard tissue debris accumulation, canal transportation, and centering ratio) as well as fracture resistance. Therefore, further studies are required for accepting contracted access cavity, and modified form of traditional and contracted access cavity could be considered.

• Restorative Dentistry and Endodontics
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• v.21 no.1
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• pp.35-53
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• 1996

The development and repair requires the formation of new tissues comprised of various extracellular matrix components. The present study investigated the formation and distribution of the major ECM components such as type I collagen, type III collagen, fibronection, bone sialoprotein, and osteonection during development and repair. For developing observation. Sprague-Dawley rats weighing $27{\pm}1gm$ were sacrificed. For repair observation, Sprague-Dawley rats weighing $110{\pm}5gm$ were used. The pulp perforation were prepared on mesial surface of the maxillary first molar by using 1/2round bur. At 5 days after perforation, rats were sacrificed by perfusion with 3 % paroformaldehyde. The maxillary first molar region were cut, demineralized, dehydrated and embedded in paraffin. Immunostaining the ECM components was achieved by the avidin-biotin complex method. The results as follows : 1. Bright immunoreaction for fibronectin was present in the basement membrane at the inner epithelial-mesenchymal interface, especially concentrated in the blood vessel walls, cell membrane of odontoblasts, and initial predentin. 2. Type I and III collagen was observed in the newly formed pulp tissue, predentin, and its intensity increased as more of these components during repair. 3. Strong immunostaining for bone sialoprotein and osteonectin was found in dentin while no or weaker staining was observed loose connective tissue of the pulp. 4. These results suggest that develpment and repair is achieved through a series of cell differentiation and attachment by the specific ECM components.

• Restorative Dentistry and Endodontics
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• v.21 no.1
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• pp.218-226
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• 1996

This study was performed to evaluate the possibility of pulpal damage by measuring temperature change occured in dentin according to the thickness of dentin, the time of irradiation and the output of laser energy when the dentin surfaces were irradiated with Nd-YAG laser under water coolant and no water coolant. Sound upper and lower molar teeth were sectioned with 1mm, 1.5mm and 2mm thickness of dentin discs and divided into 4 groups by dentin thiness. 0.5 watt, 1 watt, 1.5 watt and 2 watt-energied beam of pulsed 10 p.p.s of Nd : YAG laser was applied respectively to dentin surfaces for 8 secs and 16 secs when water coolant is used or not.Ant then the temperature changes occurd in dentin were measured at opposite surfaces of laser-irradiated dentin surfaces with digital thermometer. The results were as follow. 1. When the amount of irradiated energy was same, the temperatue changes of dentin were higher as the thickness of dentin discs was thinner(p<0.01). 2. When the amount of irradiated energy and the thickness of dentins were same, The temperature changes of dentin were lower under water coolant than under no water coolant in all groups(p<0.01). 3. With the increase of time of irradiation, the temperature changes of Dentin became higher in all groups and were steeply increased at initial period of irradiation of laser. 4. Under the same thickness of dentin, the temperature changes of dentin became higher as irradiated energy was increased. These results suggest that when the beam of Nd : YAG Laser is irradiated to dential hard tissue, amount of irradiating energy, thickness of dentin, using water coolant must be considered in order to minimize thermal damage of the pulp.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.1
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• pp.19-26
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• 1997

Odontodysplasia is a rare developmental anomaly of tooth formation in which hard tissue are affected. Odontodyplasia affects the primary and permanent dentitions in the maxilla, mandible, or both jaws. The maxilla is involved twice as often as the mandible. The condition is more common in female than in male patients and in the anterior than in the posterior regions. The clinical manifestation of odontodysplasia are hypoplasia and hypocalcification of the enamel and dentin of affected teeth. Teeth tend to be small and discolored, with short roots and widely open pulp canal. Delayed eruption of affected teeth with abscess formation is common. Radiographically teeth assume a faint radiolucent image ("ghost teeth"). enamel and dentin appear thin and are similar in radiodensity. The pulp chambers are often larger than normal, calcifications(pulp stone and denticle) are found within them. The etiology of regional odontodysplasia is unknown. However, several causes have been discussed, including somatic mutation, local circulatory disorders, local trauma, failure of migration and differentiation of neural crest cells, local infection.

• Restorative Dentistry and Endodontics
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• v.40 no.3
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• pp.179-187
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• 2015

Traditionally, apexification has been used to treat immature permanent teeth that have lost pulp vitality. This technique promotes the formation of an apical barrier to close the open apex so that the filling materials can be confined to the root canal. Because tissue regeneration cannot be achieved with apexification, a new technique called regenerative endodontic treatment was presented recently to treat immature permanent teeth. Regenerative endodontic treatment is a treatment procedure designed to replace damaged pulp tissue with viable tissue which restores the normal function of the pulp-dentin structure. After regenerative endodontic treatment, continued root development and hard tissue deposition on the dentinal wall can occur under ideal circumstances. However, it is difficult to predict the result of regenerative endodontic treatment. Therefore, the purpose of this study was to summarize multiple factors effects on the result of regenerative endodontic treatment in order to achieve more predictable results. In this study, we investigated the features of regenerative endodontic treatment in comparison with those of other pulp treatment procedures and analyzed the factors that have an effect on regenerative endodontic treatment.

• The Journal of the Korean dental association
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• v.48 no.11
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• pp.803-812
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• 2010

Regenerative endodontic procedure (REP) is a treatment option to replace damaged pulp tissue with the viable tissue which restores the normal function of the pulp-dentin complex. Possible reason for doing REP is not clearly known, however, clinicians perform REP in order to recover the histological structure as well as function of the traumatized and diseased tooth so that this tooth can restore its original root shape and thickness. This REP can be explained by the concept of revascularization or revitalization after induction of blood clot formation in the canal space. For this purpose, several treatment strategies have been suggested. In this regard, the rationale for the application of triantibiotics, calcium hydroxide or mineral trioxide aggregate is discussed in this paper. As a result, we will try to find the best method for REP by reviewing each available technique and their advantages and disadvantages.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.2
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• pp.475-483
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• 1997

Fracture of the crown in a permanent incisor is relatively common. When it occurs with pulp exposure, it presents both restorative and endodontic problems. In the restoration of a fractured incisor, reattachment of the original fragment or restoration with a composite resin is preferred over a temporary crown. If fractured fragment is intact, the tooth can be restored with reattachment of the fragment. An exposed pulp in a young crown-fractured incisor is usually treated with either pulp capping or pulpotomy depending on the size of an exposure and time elapsed since injury. However, in teeth showing vital and/or hyperplastic pulp tissue at the exposure, only superficial layers of the pulp and surrounding dentin should be removed : i.e. partial pulpotomy can be performed in immature as well as mature teeth. This paper reports 2 cases of crown-fractured permanent incisors with pulp exposure that had been treated by reattachment of original fragment followed by partial pulpotomy or partial pulpectomy. The following results are obtained. ; 1. Fragment reattachment is an acceptable semi-permanent restoration of crown fractured young permanent incisor. 2. Partial pulpotomy is recommended as the treatment of choice in crown-fractured permanent teeth with pulp exposure.

• Restorative Dentistry and Endodontics
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• v.20 no.2
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• pp.744-757
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• 1995

Implantation of demineralized bone matrices was done into the amputated pulp in vivo and sequential reaction of the pulpal ectomesenchymal cells was observed. The bone matrices, obtained from cat long bone were crushed into below $700{\mu}m$, demineralized with 0.5N HCl and allografted into pulp of molar teeth. At seven days after implantation many undifferentiated mesenchymal cells aggregated near the matrices in the pulpal tissue. At fourteen days after implantation, the cells differentiated into preosteoblast-like cells which have secretory cell characteristics. At one or two months after implantation osteoid tissue was formed. The cells, which are located at the surface of the tissue, contained abundant dilated rough endoplasmic reticulum, Golgi apparatus and secretory granules in the cytoplasm. The matrix of the tissue has less collagen fibers than those in normal dentin. These results suggest that the interaction of pulpal mesenchymal cells with demineralized bone matrix can be a model which induces mineralization.

• Restorative Dentistry and Endodontics
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• v.25 no.4
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• pp.509-526
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• 2000

It is known that injuries to the dentin have a corresponding inflammatory effect on the pulp and these inflammatory effects frequently result in pulpal pathoses due to progressive degradation of pulpal connective tissue. It was supposed that the tissue degradation in different inflammatory process was controlled by proteinase activity and antiproteinase activity. Therefore, the purpose of this study was to examine the pulp and periapical pathoses in terms of the activities of proteinase and proteinase inhibitor, 37 pulpal tissues were divided by clinical diagnostic criteria into normal pulp, acute inflamed pulp, and chronic inflamed pulp, and then those groups were subdivided by histopathological findings into 5 pulpal pathoses groups, i.e. normal pulp (P1, n=8), chronic pulpitis with fibrotic change (P2, n=2), chronic pulpitis with dystrophic calcification (P3, n=11), chronic pulpitis with pulp abscess (P4, n=7), acute pulpitis with necrotic change (P5, n=4), 26 periapical tissues were also divided by ordinary histopathological findings into 3 periapical pathoses group, i.e., granuloma (A1, n=17), cyst (A2, n=2) and abscess (A3, n=7). The activities of proteinases (cathepsin G, MMP-3) and proteinase inhibitors (${\alpha}1$-AT, TIMP-1 and, SLPI) were evaluated by RT-PCR and immunohistochemical methods. The results were as follows. 1. Generally, the intensity of immunohistochemical staining of proteinases and proteinase inhibitors increased in P2 and P5 groups compared to P1 group. 2. The immunohistochemical stain of proteinases and proteinase inhibitors was intensely detected in P2 group, showing low inflammatory reaction and low tissue degradation, but it was reduced in P3 and P4 groups, showing severe tissue degradation. 3. The distribution of proteinases and proteinase inhibitors in pulpal pathoses was consistently presented by immunohistochemical staining, while the expression of proteinase and/or proteinase inhibitors mRNAs in pulpal pathoses was occasionally detected by RT-PCR methods. 4. RT-PCR of proteinase and proteinase inhibitors was usually positive in P2, showing rare tissue degradation, but it was almost negative in P3 and P4, showing severe tissue degradation. 5. We presume that the reason why the level of proteinase and proteinase inhibitors was so sparse in RT-PCR method is due to the abrupt decrease of mRNA synthesis or degradation of synthesized mRNA of proteinase and/or proteinase inhibitors depend on the inflammatory reaction and/or on the degradation of pulp tissues(P3, P4). 6. Pulpal pathoses groups showed significant lower RT-PCR detection of proteinases and proteinase inhibitors than the periapical pathoses group(p<0.05), and there is no significant difference among the periapical pathoses groups(p>0.05).