• The Journal of Korean Academy of Prosthodontics
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• v.35 no.2
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• pp.255-264
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• 1997

The conventional osseointegration protocol calls for waiting up to 12 months for ossification of an extraction socket to heal before placing an endosseous implant. In this study, the possibility of placing a pure titanium implant directly into an extraction socket immediately after extraction was investigated. And the marginal bone loss of immediate nonsubmerged and submerged endosseous dental implants placed into extraction sockets was also compared. Pure titanium Nobelpharma Branemark implants and solid screw type ITI implants were placed into premolar extraction sockets of two adult dogs and allowed to heal for a period of 3 months, followed by functional loading of the implant. Radiographic examination was performed before implantation, immediately after implantation and 3, 6, 9, 12 months after implantation. The results obtained were as follows : 1. Immediately placed nonsubmerged ITI implants and submerged Branemark implants showed favorable radiographic osseointegration status and there were minimum marginal bone loss. 2. There were no significant differences in radiographic finding of osseointegration between conventional and immediate implantation. 3. Gingival tissue around implants showed more inflammatory signs than that of adjacent natural teeth. This study suggest that pure titanium Branemark implants and submerged ITI implants have the potential to integrate when placed immediatly after extraction of the teeth and warrants further investigation.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.1
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• pp.73-79
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• 2000

A material of 48 patients with 60 avulsed and replanted permanent teeth were followed retrospectively in the period of 1996. 1 to 1998. 12 (mean observation period=1year 7months). The age of the patients at the time of replantation ranged from 9 to 63 years (mean=24 years). Clinical records of patients were reviewed to obtain valid data concerning the extent of injury and treatment provided. Pulpal and periodontal healing states were examined with periapical x-rays and clinical examination procedures (i.e. percussion test and mobility test) at their recall visit. Root ankylosis was found in fifty-two teeth(87%) and root resorption in twenty-four(40%). Only two of the replanted teeth(3%) showed partial regeneration of the periodontal ligament. Six teeth(10%) resulted in tooth loss, but the remaining fifty-four were clinically well functioning. Most of teeth have mild marginal bone loss accompanied by gingival retraction without pathological periodontal pockets. The incidence of root resorption was much higher in younger age group. However, it was not affected by the interval between avulsion and replantation, the condition of supporting tissues, the degree of root formation and the type of splinting, indicating that multiple factors involved in determining the prognosis of replanted teeth. Based on these findings, avulsed teeth in unfavorable conditions (i.e. long extra-alveolar periods, etc.) should be preserved if possible.

• Restorative Dentistry and Endodontics
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• v.26 no.6
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• pp.492-498
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• 2001

The purpose of this study was to evaluate four different composite resins in vitro for microleakage in Class II box type restorations that have gingival margins apical to the cementoenamel junction. Forty caries free extracted human molars were used in this study. The Class II cavities were prepared 1.0mm below cementoenamel junction with a #701 carbide bur. The teeth were randomly divided into four groups, each group comprising 20 treated cavities according to adhesives and filling materials ; Group 1: Scotchbond Multipurpose/Z 100. Group 2: Ariston Liner/Ariston pHc, Group 3: One Step/Pyramid, Group 4: Prime & Bond NT/SureFil. To simulate the clinical situation during restoration placement, a restoration template was fabricated and composite resin was filled using a three sited light-curing incremental technique. The specimens were stored in the 100% humidity for 7 days prior to thermocycling. The specimens were immersed in 2% methylene blue dye solution for 24 hours and then embeded in transparent acrylic resin and sectioned mesiodistally with a diamond wheel saw. The degree of marginal leakage was scored under the stereomicroscope($\times$20) and the data were analyzed by Kruskal Wallis test and Mann Whitney test. (omitted)

• The Journal of the Korean dental association
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• v.50 no.8
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• pp.474-481
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• 2012

The periodontal flap surgery is the most widely utilized surgical procedure to reduce the pocket depth and to access the subgingival root surfaces for scaling and root planing. The diagnosis of the periodontal lesion and the objective of the surgery will dictate the type of flap procedure which will be utilized to obtain the best result. The incisions, type of flap and the selection of suturing design must be planned and executed to fit the problem. Periodontal flaps are designed to preserve gingival integrity and to gain access to root surfaces for residual calculus removal and to thoroughly remove granulation tissue so bone defects can be visualized and treated. Gentle and efficient procedures result in optimum healing and minimal postoperative pain. When flaps need to be repositioned apically or less often, coronally, then the flaps must sit passively at the appropriate level before suturing. To ensure this, buccal and lingual flaps need to be elevated beyond the mucogingival junction so the elasticity of the mucosa allows for flap mobility. Sometimes it may be necessary to extend the flap elevation apically with a split incision approach to minimize the effect of the less elastic periosteum. Vertical incisions can aid in flap positioning by allow ing the clinician to suture the flap at a different level to the adjacent untreated gingiva. In osseous periodontal surgery, flaps are apically positioned to minimize postoperative pocket depth. In regenerative periodontal surgery including implant surgery, soft tissue cove rage of bony defects, graft materials, membranes, and bio logic agents is important so sulcular incisions and light suturing techniques are crucial.

• Journal of Periodontal and Implant Science
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• v.50 no.2
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• pp.83-96
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• 2020

Purpose: The present study aimed to evaluate the clinical benefit of additional toothbrushing accompanying non-surgical periodontal treatment on oral and general health in patients with type 2 diabetes mellitus (T2DM). Methods: We conducted a doubled-blind randomized controlled trial in 60 T2DM patients between June 2013 and June 2014. The patients were randomly assigned to the scaling and root planing (SRP) group; the scaling and root planing with additional toothbrushing (SRPAT) group, in which additional toothbrushing was performed by toothpick methods; or the control group. Microbiological and oral examinations were performed for up to 12 weeks following treatment. Non-surgical treatment was conducted in the experimental groups. The SRP group received scaling and root planing and the SRPAT group received additional toothbrushing with the Watanabe method once a week from the first visit through the fifth visit. The primary outcomes were changes in haemoglobin A1c (or glycated haemoglobin; HbA1c) levels, serum endotoxin levels, and interleukin-1 beta levels. Periodontal health status was measured by periodontal pocket depth, the calculus index, and bleeding on probing (BOP). Results: Both the SRP and SRPAT groups showed improvements in periodontal health and HbA1c, but the SRPAT group showed significantly less BOP than the SRP group. Furthermore, only the SRPAT group showed a statistically significant decrease in serum endotoxin levels. Conclusions: Non-surgical periodontal treatment was effective in improving HbA1c and serum endotoxin levels in T2DM patients. Furthermore, non-surgical treatment with additional tooth brushing had a more favourable effect on gingival bleeding management. Trial RegistrationClinical Research Information Service Identifier: KCT000416.

• The Journal of Korean Medicine
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• v.39 no.1
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• pp.63-74
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• 2018

Objectives: Periodontitis is an inflammatory disease with the destruction of periodontal ligament, alveolar bone loss and inflammation of gingva, leading to teeth loss. Eclipta prostrata L. (Ecliptae Herba) has been used to treat the inflammatory disease as a Korean traditional medicine. The aim of this study is to investigate the effects of E. prostrata L. on periodontitis. Methods: E. prostrata L. was extracted with water and lyophilized. The aqueous extract of E. prostrata L. (EP) was topically applied to the periodontal lesion for 2 weeks. To induce the periodontitis, a 3-0 nylon ligature was placed around the cervix of the lower first molar in rat. Rats were divided into 3 groups (n = 7); NL group (non-ligatured and non-treated), L group (ligatured and vehicle-treated) and EP group (ligatured and EP-treated). After sacrifice, the mandibles was dissected and stained with methylene blue solution to analyze the alveolar bone loss. The expression of MMP-9 was determined in gingival tissues. To confirm the effect of EP on recovery of gingiva, mRNA expressions of type I pro-collagen and MMP-9 levels were investigated in LPS-treated HS68 fibroblast cells. In addition, inflammatory mediators were evaluated in LPS-treated RAW264.7 cells. Results: Alveolar bone loss was significantly inhibited by EP treatment. The mRNA expression of MMP-9 was attenuated in rats treated with EP. In addition, treatment with EP increased the expression of type I pro-collagen, while the expression of MMP-9 was decreased in LPS-stimulated HS68 fibroblast cells. Furthermore, EP down-regulated the LPS-induced IL-6, $TNF-{\alpha}$, COX-2 and iNOS production in RAW264.7 cells. Conclusions: These results suggest that EP have ameliorative effects on periodontitis through inhibiting alveolar bone loss and modulating the inflammatory mediators. Therefore, E. prostrata L. may be an alternative on patients with periodontitis.

• International Journal of Oral Biology
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• v.32 no.1
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• pp.35-43
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• 2007

Tooth loss in elderly is mainly caused by alveolar bone loss via severe periodontitis. Although the severity of periodontitis is known to be affected by age, the aging process or the genetic changes during the aging of periodontal tissue cells are not well characterized. In this study, we investigated the effect of in vitro aging on the change of gene expression pattern in periodontal fibroblasts. Gingival fibroblasts (GF) and periodontal ligament fibroblasts (PDL) were obtained from two young patients and replicative senescence was induced by sequential subcultivation. When more than 90% cells were positively stained with senescence-associated ${\beta},-galactosidase$, those cells were regarded as aged cells. In aged GF and PDL, the level of phosphorylated retinoblastoma (RB) and $p16^{INK4A}$ protein was significantly decreased and increased, respectively. However, the protein level of p53 and p21, well known senescence-inducing genes, did not increase in aged GF and PDL. Although $p27^{Kip1}$ and $p15^{INK4B}$, another cyclin-dependent kinase inhibitors, were reported to be involved in replicative senescence of human cells, they were decreased in aged GF and PDL. Because senescent cells showed flattened and enlarged cell shape and are known to have increased focal adhesion, we examined the protein level of several integrins. Aged GF and PDL showed increased protein level of integrin ${\alpha}2$, ${\alpha}v$, and ${\beta}1$. When the gene expression profiles of actively proliferating young cells and aged cells were compared by cDNA microarray of 3,063 genes and were confirmed by reverse transcription-polymerase chain reaction, 7 genes and 15 genes were significantly and commonly increased and decreased, respectively, in aged GF and PDL. Among them, included are the genes that were known to be involved in the regulation of cell cycle, gene transcription, or integrin signaling. The change of gene expression pattern in GF and PDL was minimally similar to that of oral keratinocyte. These results suggest that $p16^{INK4A}/RB$ might be involved in replicative senescence of periodontal fibroblasts and the change of gene expression profile during aging process is cell type specific.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.2
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• pp.107-112
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• 2013

Complications increases when crown height space is excessive and one should be careful of choosing type of fixed prosthesis in case crown height space is over 12 mm. In this condition, tooth seems to be longer, therefore, it is needed to use gingival shade in aesthetically important area for fixed prosthesis. In this case, fixed prosthesis which has inappropriate maintenance and hygiene could hold food, plaque, calculus, thus increase incidence of inflammation and infection. Moreover, it could lead to chronic inflammation and infection and in that case surgical improvement could be necessary. In present case report, gingival inflammation and swelling developed around prosthesis after having made it considering articulation and aesthetic view in patient who had excessive crown height space. Finding out that design of prosthesis is a factor to make it hard to maintain oral hygiene, a temporary prosthesis which has enough interproximal space and proper emergence profile was fabricated. After two months of observation, significant abnormal symptoms are not found and oral reconstruction is performed using fixed prosthesis with zircornia infrastructure and porcelain build-up based on convenient self hygiene design. Through serial treatment, inappropriate soft tissue response is not observed and satisfactory result in functional aspect comes out.

• Journal of Periodontal and Implant Science
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• v.27 no.4
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• pp.883-908
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• 1997

Bone remodeling is characterized by the coupling of osteoclast-mediated bone resorption and osteoblast-mediated bone formation. The process is tightly regualted at the local level by an incompletely known netwotk of peptide and non-peptide fators. Nitric oxide(NO), synthesized by nitric oxide synthetase(NOS) from L-arginine, is becoming recognized as an important bioregualtory molecule in a variety of tissue, but little is known about its possible role in periodontal tissue. The purpose of this study is to investigate the expression of nitric oxide synthetase(NOS) in inflamed gingiva and the effects of cytokine on the expression of NOS protein. The expression of NOS in gingival tissue was evaluated by immunohistochemical staining for $NOS_1$, $NOS_2$, $NOS_3$. The effect of cytokine on the expression of NOS in human periodontal ligament cells and osteoblast-like HOS cells by western blot analysis. Further, we studied that NO functions in periodontal ligament cells as a regulatory molecule. PDL cells incubated with NOS inhibitor and donor. The protein expression, type I collagen & non-collagenous protein, nitrate production and cell proliferation were evaluated The results were as follows. 1. $NOS_1$, $NOS_2$, $NOS_3$ was rarely distributed in healthy gingiva, but stronger stained in gingival epithelium, endothelial cells, and mononuclear cells of inflammed gingiva. 2. The cytokine stimulated $NOS_1$, and $NOS_3$ protein were not inducing or inhibitory effect to compared with control in PDL and HOS cells. 3.Incubation of cells with combination of $TNF-{\alpha}$, $IFN-{\gamma}$, LPS result in a time dependant increase in $NOS_2$ expression, reaching a maximal level after 24 hours of stimulation. 4. The osteonectin protein inhibitory effect of NMA, inhibitor of NOS, was reversed by Larginine in dose dependant manner. 5. NMA decreased cell poliferation and nitrate production, but the inhibitory efffect of NMA was also prevented by the NO donor, sodium nitropruiside. These results suggest that exogenously synthesized NO was playing a stimulating effect on cell proliferation or on non-collagenous protein expression. Therefore NO have an important role in mediation of localized bone destruction associated inflammatory bone disease such as periodontitis.

• Journal of the korean academy of Pediatric Dentistry
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• v.39 no.4
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• pp.412-417
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• 2012

Mucopolysaccharidosis (MPS) is a disorder which is caused by the defect of the lysosomal enzyme that is essentially needed for resolution of glycosaminoglycans (GAGs). Metabolite of GAGs will accumulate in the lysosome of cells and will result in the dysfunction of cells, tissues, and organs. Eventually, patients will manifest both mental retardation and physical disorders. In worst cases, mucopolysaccharidosis can cause premature death. The current clinical types have been classified as MPS from type I to type IX according to the defect of certain enzyme. The dental complications have been reported as delay of eruption, enamel hypoplasia, microdontia, malocclusion, condylar defects, gingival hyperplasia and dentigerous cystlike follicle. This clinical report presents the case of a boy with MPS type II, Hunter Syndrome which has various dental complications.