• Journal of Korean Dental Hygiene Science
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• v.3 no.2
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• pp.59-66
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• 2020

Dental hygienists handle periodontal tissue every day. Since periodontal tissue contains hard and soft tissue, dental hygienists need to cultivate scientific knowledge about bone tissue. This study introduces recent research results on cells and cytokines related to bone tissue. Recently, bisphosphonate-related osteonecrosis of the jaw has been reported, therefore we would like to present osteoporosis and osteoporosis treatment drugs and their side effects in this study.

• Journal of Periodontal and Implant Science
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• v.28 no.2
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• pp.205-221
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• 1998

The present study invetigates the effects of root planing only(control group), DFDBA alone(test group 1) and combined use of DFDB and Dura mater(test group 2) in dehiscence defects in dogs. The results of 8weeks post-surgery by histological comparison between the three groups are as follows. 1. The contol group showed minimum regeneration of new cementum and new bone with limited migration of epitheilal cells, and healed by connective tissue attachment. 2. The test group 1 showed minimum regeneration of new cementum and new bone with limited migration of epitheilal cells, and healed by connective tissue attachment. 3. The test group 2 showed significant amount of the new cementum and new bone. 4. Both control and test groups healed without any observable root resorption and ankylosis. The above the results suggest that the use of resorbable Dura mater only does not improve the regeneration of new bone and periodontal ligament due to difficulties of space making, but the combined use with DFDB may be more effective.

• Journal of Periodontal and Implant Science
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• v.41 no.3
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• pp.109-116
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• 2011

Purpose: The purpose of this study was to compare and quantify the expression of C-reactive protein (CRP), matrix metalloproteinase (MMP)-14, and tissue inhibitor of metalioproteinases (TIMP)-2 in gingival tissues of patients with chronic periodontitis accompanied with inflammatory reaction related to alveolar bone resorption with or without type 2 diabetes mellitus (DM). Methods: Twelve patients with type 2 DM and chronic periodontitis (group 3), twelve patients with chronic periodontitis (group 2), and twelve healthy individuals (group 1) were included in the study. Gingival tissue biopsies were collected from each patient and from healthy individuals at the time of periodontal surgery (including surgical crown lengthening) or tooth extraction. The concentrations of cytokines were determined by a western blot analysis. Results: The expression levels of CRP and MMP-14 increased in group 2 and 3, and they were highest in group 3. The expressions of TIMP-2 also increased in group 2 and 3. Conclusions: This study demonstrated that the expression levels of CRP, MMP-14, and TIMP-2 might be inflammatory markers in periodontal inflamed tissue. It can be assumed that CRP, MMP-14, and TIMP-2 may be partly involved in the progression of periodontal inflammation associated to type 2 DM.

• International Journal of Oral Biology
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• v.42 no.4
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• pp.169-174
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• 2017

Transient receptor potential melastatin 8 (TRPM8) plays a crucial role in innocuous cool sensation, acute cold pain and cold-induced hyperalgesia during pathologic conditions. To help understand TRPM8-mediated cold perception in the dental pulp and periodontal tissues, we examined the distribution of TRPM8-immunopositive (+) axons in molar and incisor pulp and periodontal tissues using transgenic mice expressing a genetically encoded axonal tracer in TRPM8+ neurons. In the radicular pulp of the molar teeth, a small number of TRPM8+ axons were observed. TRPM8+ axons branched frequently and extensively in the core of coronal pulp, forming a network in the peripheral pulp. Some TRPM8+ axons ascended between odontoblasts and were observed in the dentinal tubule. TRPM8+ axons were linear-shaped in the radicular pulp, whereas many TRPM8+ axons showed portions shaped like beads connected with thin axonal stands at the peripheral pulp. TRPM8 was densely expressed in the bead portions. In the incisor pulp, TRPM8+ axons were occasionally observed in the core of the coronal pulp and rarely observed at the peripheral pulp. TRPM8+ axons were occasionally observed and showed a linear shape rather than a bead-like appearance in the periodontal ligament and lamina propria of the gingival tissue. These findings, showing differential distribution of TRPM8+ axons between radicular and coronal portions of the molar pulp, between incisor and molar pulp, and between dental pulp and periodontal tissues, may reflect differential cold sensitivity in these regions.

• Journal of Periodontal and Implant Science
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• v.50 no.4
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• pp.226-237
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• 2020

Purpose: This study was conducted to assess the efficacy of prophylactic gingival grafting in the mandibular anterior labial area for preventing orthodontically induced gingival recession. Methods: Eight mongrel dogs received gingival graft surgery at the first (I1) and third (I3) mandibular incisors on both sides based on the following group allocation: AT group (autogenous connective tissue graft on I1), AT-control group (contralateral side in the AT group), CM group (xenogeneic cross-linked collagen matrix graft on I3) and CM-control group (contralateral side in the CM group). At 4 weeks after surgery, 6 incisors were splinted and proclined for 4 weeks, followed by 16 weeks of retention. At 24 weeks after surgery, casts were made and compared with those made before surgery, and radiographic and histomorphometric analyses were performed. Results: Despite the proclination of the incisal tip (by approximately 3 mm), labial gingival recession did not occur. The labial gingiva was thicker in the AT group (1.85±0.50 mm vs. 1.76±0.45 mm, P>0.05) and CM group (1.90±0.33 mm vs. 1.79±0.20 mm, P>0.05) than in their respective control groups. Conclusions: The level of the labial gingival margin did not change following labial proclination of incisors in dogs. Both the AT and CM groups showed enhanced gingival thickness.

• Journal of Periodontal and Implant Science
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• v.40 no.1
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• pp.33-38
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• 2010

Purpose: The purpose of this study was to observe and quantify the expression of interleukin-4 (IL-4), interferon-$\gamma$ (IFN-$\gamma$), and tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) in the gingival tissue of patients with type 2 diabetes mellitus (DM) and healthy adults with chronic periodontitis. Methods: Twelve patients with type 2 DM and chronic periodontitis (Group 3), twelve patients with chronic periodontitis (Group 2), and twelve healthy individuals (Group 1) were included in the study. Clinical criteria of gingival (sulcus bleeding index value, probing depths) and radiographic evidences of bone resorption were divided into three groups. The concentrations of cytokines were determined by a western blot analysis and compared using one-way ANOVA followed by Tukey's test. Results: The expression levels of IFN-$\gamma$ and TIMP-2 showed an increasing tendency in Groups 2 and 3 when compared to Group 1. On the other hand, the expression of IL-4 was highest in Group 1. Conclusions: The findings suggest that IFN-$\gamma$ and TIMP-2 may be involved in the periodontal inflammation associated with type 2 DM. IL-4 may be involved in the retrogression of the periodontal inflammation associated with type 2 DM.

• The Journal of the Korean dental association
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• v.57 no.12
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• pp.758-767
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• 2019

The classification of periodontal disease in 1999 has been widely used for determining a diagnosis, establishing a treatment plan, and evaluating the prognosis of the patient with periodontal disease. However, scientific evidence from many studies indicates the need for a new classification system for periodontal and peri-implant disease. Summary at 2017 world workshop as follows: 1) Periodontal health and peri-implant health was defined; 2) Chronic periodontitis and aggressive periodontitis were unified as periodontitis; 3) Periodontitis was further classified by staging and grading to reflect disease severity and management complexity, rate of disease progression, respectively; 4) Periodontal disease as manifestation of systemic disease is based on the International Statistical Classification of Diseases and Related Health Problems-10 (ICD-10) code; 5) Periodontal biotype and biologic width was replaced to periodontal phenotype and supracrestal tissue attachment, respectively; 6) The excessive occlusal force was replaced by a traumatic occlusal force; 7) ≥3 mm of radiographic bone loss, ≥6 mm of pocket probing depth and bleeding on probing indicates peri-implantitis in the absence of radiograph at final prosthesis delivery.

• The Journal of the Korean dental association
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• v.36 no.11 s.354
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• pp.794-799
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• 1998

Many references report that abnormal diastema except temporary diastema existing in mixed dentition period is caused by maxilary heavy labial frenum, malocclusion, progressive periodontal disease, and loss of posterior teeth. We can diagnose patient as diastema caused by periodontal disease, especially, in case of accompanying progressively destructed anterior maxillary alveolar bone defect, and interseptal bone defect. We report Multiple disciplinary approach for diastema associated with periodontal disease. Periodontal treatment(Guided Tissue -Regeneration, alveoloplasty, bone graft), or thodontic treatment (space closure, redistribution), and the final proshodontic restoration for retention were used.

• Journal of Periodontal and Implant Science
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• v.48 no.4
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• pp.224-235
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• 2018

Purpose: The purpose of this study was to evaluate the effects of platelet-rich plasma (PRP) on periodontal healing of replanted root surfaces in dogs histologically and histomorphometrically. Methods: A total of 36 roots of mandibular incisors and premolars from 6 mongrel dogs were used. The roots were randomly divided into 3 groups: 1) a positive control group (n=12), in which the periodontal ligament (PDL) and cementum were retained and the roots were soaked in saline; 2) a negative control group (n=12), in which the PDL and cementum were removed and the roots were soaked in saline; and 3) an experimental group (n=12), in which the PDL and cementum were removed and the roots were soaked in PRP. After soaking the root surfaces, the extracted roots were replanted into the extraction sockets. The roots were covered using a coronally repositioned flap Results: Histologically, irregular-thickness PDL-like and cementum-like tissues were observed in the 4-week experimental group and the positive control group. PDL-like tissue and cementum-like tissue with a more uniform thickness were observed at 8 weeks. In the negative control group, PDL-like tissue and cementum-like tissue were rarely found, and root resorption and ankylosis were observed. In the cross-sectional histomorphometric analysis, the experimental group demonstrated a higher rate of formation of cementum-like tissue and a lower tooth ankylosis rate than the positive and negative control groups at 4 and 8 weeks. Although there was a significant difference in the tooth ankylosis rate and the formation of cementum-like tissue across the 3 groups (P<0.05), no statistical significance was observed between any pair of groups (P>0.017). Conclusions: Applying PRP to root surfaces during tooth replantation in dogs can reduce tooth ankylosis and increase PDL-like and cementum-like tissue formation.

• Journal of Periodontal and Implant Science
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• v.26 no.3
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• pp.735-751
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• 1996

An ultimate goal of periodontal therapy is to stop the disease process and to regenerate a functionally-oriented periodontium destroyed as a result of periodontal disease. The purpose of this study was to observe the effect of grafting granulation tissue obtained from extraction socket on the regeneration of horizontal furcation defect. Six dogs were used in this study. All mandibular first and third premolars were extracted. At 2, 3, and 5 days after extraction, tissues were obtained from extraction socket of 1 mongrel dog and examined by light microscope. Granulation tissue obtained at 5 days after extraction was chosen as the graft material. Five days later, horizontal furcation defects were created surgically at mandibular second and fourth premolars in the right and left side of the 5 beagle dogs. The entrance area of the artificially prepared "key hole" defects were about $3\;4mm^2$. By random selections, 2 exposed furcation defects were grafted with granulation tissue obtained from extraction socket as experimental group and 1 furcation defect was as control. The flaps were replaced to their original position and sutured with 4-0 chromic cat-gut. Three dogs were sacrificed 4 weeks and two dogs 8 weeks after surgery, and the prepared specimens were examined by light microscope. At 4 weeks, furcations were filled with epithelial lining and fibrous connective tissue infiltrated with chronic inflammatory cells. New bone formation was observed in all groups. Only experimental group showed new cementum formation. At 8 weeks, new cementum, functional arrangement of new PDL fiber, root resorption, and some ankylotic union of newly formed alveolar bone and root surface were observed in all groups. Experimental group showed that epithelial downgrowth was inhibited and new bone formation was more active compared to control. The success rate of the furcation defect healing was higher in experimental group than control. These results suggested that grafting of granulation tissue obtained from extraction socket which combined with reconstructive periodontal flap surgery may promote periodontal regeneration of horizontal furcation defect.