• Restorative Dentistry and Endodontics
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• 제24권2호
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• pp.286-298
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• 1999

The endodontic-periodontic combined lesions have been difficult to get correct diagnosis and predictable treatment. This study was to make the experimental endodontic-periodontic combined defects in dogs for the study of the periodontal regeneration and to evaluate the efficacy of the enamel matrix protein and e-PTFE membrane in the experimental endodontic-periodontic combined defects. 5 mongrel dogs were used. The pulp chambers were opened and the plaque was inserted into the chambers to induce the periapical lesions on the mandibular second, third and fourth premolars of the dogs. 1 month later, the root canal treatments were done with gutta perch a and ZOE sealer. On the day of surgery, the periapical defects were standardized by trephine bur. The buccal dehiscence defects were made by the dental bur and bone chisels. The apicoectomy with retrofilling was done. The prepared roots were randomly selected for test and control groups. In the experimental groups, the enamel matrix derivative and e-PTFE membrane were used. Nothing was placed on the control group. Fluroscent labelling was used to evaluate the bone formation. After 4 and 12 weeks, the dogs were sacrificed and undecalcified sections were prepared and stained with toluidine blue. Those histologic sections were examined by fluorescent microscopy and light microscopy. The results were as follows. 1. In the control group, new bone was formed in the periapical defects and scarcely in the buccal dehiscence defects. New cementum was not detected at 4 and 12 weeks. 2. In the experimental groups, new bone, new cementum and periodontal ligament were found in the periapical and buccal dehiscence defects. The relative amount and the quality of the new bone, new cementum and periodontal ligament tissue that had formed on the experimental groups were superior to those of the control group. 3. The current observation implicated that e-PTFE membrane and enamel matrix protein could be the effective tools for the guided tissue regeneration of the endo-perio combined defects.

• Journal of Periodontal and Implant Science
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• 제51권3호
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• pp.163-178
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• 2021

Purpose: The aim of this study was to evaluate clinical factors affecting the longevity of fixed retainers and the influence of fixed retainers on periodontal health in periodontitis patients. Methods: In total, 52 patients with at least 2 years of follow-up after periodontal and orthodontic treatment were included in this study. After scaling and root planing, orthodontic treatment with fixed appliances or clear aligners was performed. Fixed retainers with twist-flex stainless steel wires were bonded to the palatal or lingual sides of anterior teeth. Changes in clinical parameters, including the plaque index, gingival index, calculus index (CI), probing pocket depth, and radiographic bone levels, were evaluated before bonding of fixed retainers and at a 12-month follow-up. Cumulative survival rates (CSRs) for retainer failure were evaluated according to sex, site, CI, stage of periodontitis, and the severity of the irregularity with the log-rank test and hazard ratios (HRs). Results: Twelve months after bonding of fixed retainers, improvements were observed in all clinical parameters except CI and radiographic bone gain. The overall CSR of the retainers with a CI <1 at the 12-month follow-up after bonding of fixed retainers was significantly higher than that of the retainers with a CI ≥1 at the 12-month follow-up (log-rank test; P<0.001). Patients with stage III (grade B or C) periodontitis had a higher multivariate HR for retainer failure (5.4; 95% confidence interval, 1.22-23.91; P=0.026) than patients with stage I (grade A or B) periodontitis. Conclusions: Although fixed retainers were bonded in periodontitis patients, periodontal health was well maintained if supportive periodontal treatment with repeated oral hygiene education was provided. Nonetheless, fixed retainer failure occurred more frequently in patients who had stage III (grade B or C) periodontitis or a CI ≥1 at 12-month follow-up after bonding of fixed retainers.

• Journal of Periodontal and Implant Science
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• 제34권1호
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• pp.71-81
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• 2004

Peri-implantitis could be the result of biomechanical and occlusal overload as well as microbiologic invasion. The dental implant may be more susceptible to dental plaque than the natural tooth, as the predictability of a stable soft tissue attachment complex has not yet been confirmed. With the development of peri-implantitis, the implant surface would be exposed to the oral environment and becomes coated with bacteria. The objective of therapy for this condition is to regain integration of the implant with bone. Since fibroblast adherence to surfaces is impeded by endotoxin, it would seem that decontamination would be desirable to obtain maximum osseointegration. The purpose of this study was to determine whether various chemotherapeutic and mechanical treatments(distilled water, air-powder abrasive, hypersaturated citric acid, tetracycline) can detoxify contaminated titanium implant surface by means of kinetic LAL test. Experimental rough surface titanium disks were fabricated. All of them were divided into two groups(A.a group and P.g group) and each contaminated by A. actinomycetemcomitans and P. gingivalis suspension. Contaminated disks were treated with distilled water, air-powder abrasive, citric acid and tetracycline, and then all disks were placed into LPS-free water for elution. The results were as follows : 1. In A.a group, LPS elute level of all test groups were significantly lower than control group(p<0.05). 2. In A.a group, LPS elute level of test 2, test 3 and test4 groups were significantly lower than that of control group(p<0.05). But, among the test 2, test 3, test4 groups, the significant differences were not detected. 3. In P.g group, LPS elute level of test 2, test 3 and test 4 groups were lower than that of control group(p<0.05). But, among the test groups, the significant differences were not detected. From the result of this study, it would be concluded that air-powder abrasive, hypersaturated citric acid and tetracycline treatments may be effective at reducing endotoxin level on rough titanium implant surfaces, and can be clinically used. But the treatments in peri-implantitis differentially impact osseointegration making one method clinically superior. To gain this knowledges, further molecular biologic and histopathologic studies should be developed.

• 대한소아치과학회지
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• 제35권1호
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• pp.1-10
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• 2008

치아 우식증과 침식증의 진단과 예방에 있어 구강 내 환경, 특히 산도를 정밀하게 평가하는 것은 매우 중요한 일이다. 본 연구는 구강 내의 산도측정을 위한 기존 방법들의 단점을 보완하고자 구강 내 무선 pH 원격측정 방법을 개발하고, 실제로 측정시의 효율성을 얻기 위해 시행되었다. 구강 외로 부착되는 부가적인 장치 없이 구강 내에만 장착하여 24시간 이상 수소이온농도지수(이하 pH)를 측정할 수 있는 무선 원격측정장치를 개발하고, 정확한 산도의 측정이 가능한지를 검증하였다. 그리고 이 장치를 실제 구강 내에 장착하여 피검자로 하여금 24시간 동안의 시간별 상세한 섭식과 활동 내용, 수면 상태를 기록하도록 하고 24시간 후 구강으로부터 수거하여 지난 24시간 동안의 pH의 변화를 획득하고 분석하였다. 그 결과, 구강 내 장치와 구강 외 장치로 이루어진 구강 내 무선 pH 원격측정방법의 개발에 성공하였으며 24시간 동안 피검자의 구강 내 pH 변화를 측정한 결과, 피검자가 실제 섭취하였던 시간과 음식 종류에 일치하게 측정치를 얻을 수 있었다. 본 연구를 통하여 장시간 무선 pH 원격측정방법을 이용하여 구강 내 pH를 측정할 수 있게 됨으로써, 기존의 유선 pH 원격측정방법이 가진 한계점을 극복할 수 있게 되어 구강 내 환경이나 우식학과 관련된 보다 광범위한 연구가 가능하게 될 것이다.

• Journal of Periodontal and Implant Science
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• 제24권1호
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• pp.1-14
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• 1994

Dental calculus which is calcifing and/or calcified dental plaque is divided into supragingival calculus and subgingival calculus according to the position of deposit to gingival margin. Subgingival calculus has more important clinical significance in diagnosis and treatment of periodontal disease than supragingival calculus. In order to investigate the deposition pattern of subgingival calculus on each root surface of different tooth type, extracted 192 teeth due to excessive destruction of periodontal tissue were divided according to tooth type and the deposition pattern of subgingival calculus was classified into linear type, veneer type, scattered type, and aggregated type according to the configuration and the extent of deposit. The difference of percentage between each deposition pattern was statistically analyzed by Chi-Square test. Following results were obtained : l. In maxillary incisors, linear type and aggregated type were predominant deposition pattern of subgingival calculus on labial(45.5%, 36.4%) and palatal(36.4%, 36.4%) root surface, aggreated type(72.7%) was on mesial surface, and aggregated type(54.5%) and scattered type(36.4%) was on distal suface. 2. In mandibular incisors, scattered type, linear type and aggregated type were predominant deposition pattern of subgingival calculus on labial(33.3%, 30.6%, 27.8%) and lingual(36.1%, 30.6%, 25.0%) root surface, aggregated type(33.3%), scattered type(27.8% ), and veneer type(27.8%) were on mesial surface, and aggregated type(38.9%) and scattered type(33.3%) on distal surface. 3. In maxillary peremolars, the predominant deposition patterns of subgingival calculus were linear type(28.6%) on buccal root suface, scattered type(35.7%) and linear type(28.6%) on palatal surface, scattered type(39.3%) on mesial surface, aggregated type(46.4%) on distal surface, and aggregated type(53.6%) on furcation area. 4. In mandibular premolars, scattered type was predominant deposition pattern of subgingival calculus on buccal(39.3%) and lingual(50.0%) root surface, scattered type(32.1%) and aggregated type(32.1% ) were on mesial surface, and aggregated type(42.9%) was on distal surface. 5. In maxillary molars, aggregated type(40.0%) and scattered type(32.5%) were predominat deposition pattern of subgingival calculus on buccal root surface, aggregated type was on distal(40.0%) and furcation area(50.0%), but there was no predominat pattern on palatal and mesial root surfaces. 6. In mandibular molars, aggregated type(39.5%) and scattered type(28.9%) were predominant deposition patterns of subgingival calculus on buccal root surface, aggregated type(36.8%) was on lingual surface, linear type(39.5%) and aggregated type(34.2%) were on furcation area, but there was no predominant pattern on mesial and distal root surfaces.

• 대한본초학회지
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• 제31권5호
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• pp.7-13
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• 2016

Objectives : Camellia sinensis (Theaceae) possesses a various beneficial effects such as free radical-scavenging, inactivation of urokinase in cancer cell proliferation, antibacterial, and hypotensive. Dental caries is one of the most common oral infectious disease in a human. Oral microorganisms play a significant role in the etiology of dental caries. An aberration to this ecology due to dietary habits, improper oral hygiene or systemic factors lead to an increase in cariogenic microorganisms. Cariogenic microorganisms like Streptococcus mutans and Streptococcus sobrinus encourage the accumulation and adherence of plaque biofilm by metabolizing sucrose into glucans. The purpose of this study was to investigate the antimicrobial activity of phenolic compounds of Camellia sinensis and R-carvone, monoterpenes, is can be found naturally in numerous essential oils, on Streptococcus mutans and Streptococcus sobrinus .Methods : The antimicrobial activity of these compounds was determined by the broth microdilution method and checkerboard dilution assay to investigate the potential synergistic effects of each five compounds of Camellia sinensis (C. sinensis) and R-carvone.Results : C. sinensis-isolated compounds and R-carvone were determined with MIC of more than 1,000 ㎍/mL. However, the combination test showed significant synergism against S. mutans and S. sobrinus, implicated in the lowered MICs.Conclusions : These results suggest that combinatory application of phenolic five compounds (theophyllin, l-theanine, epicatechin, epicatechin gallate, and caffeine) from C. sinensis and R-carvone has a potential synergistic effect and thus may be useful as a mouthrinse in helping control cariogenic microorganism.

• Journal of Periodontal and Implant Science
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• 제44권3호
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• pp.126-133
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• 2014

Purpose: Smokeless tobacco-based oral-use products like gutka are popular in India. Gutka usage leads to increased periodontal destruction and inflammation; however, the relevant mechanism remains unknown. This study aimed to elucidate the role of gutka in periodontitis by examining its effect on the levels of interleukin (IL) $1{\beta}$ and IL-8 from the gingival crevicular fluid (GCF). Methods: A total of 45 patients were enrolled in this study. Thirty patients with periodontitis (15 gutka chewers [GCP] and 15 nongutka chewers [NGC]) and 15 periodontally healthy controls (HC) were selected. The full-mouth plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL), and recession (RC) were recorded. The IL-$1{\beta}$ and IL-8 levels in the GCF of all subjects were assessed through an enzyme-linked immunosorbent assay (Quantikine). Results: The IL-$1{\beta}$ and IL-8 levels were not significantly higher in the GCP group (IL-$1{\beta}$, $369.01{\pm}273.44{\mu}L$; IL-8, $205.97{\pm}196.78{\mu}L$) as compared to those in the NGC group (IL-$1{\beta}$, $195.57{\pm}96.85{\mu}L$; IL-8, $178.61{\pm}149.35{\mu}L$). More gingival RC and loss of attachment was seen among the GCP group (RC: $2.02{\pm}0.31$, P=0.013; CAL: $4.60{\pm}0.56$, P<0.001) than among the NGC group (RC, $1.21{\pm}1.15$; CAL, $3.70{\pm}0.32$); however, PD was deeper among the NGC subjects (P=0.002). PI and GI were significantly higher for the periodontitis group (P<0.001) when compared to the HC, but there was no difference among gutka chewers and non-chewers (P=0.22 and P=0.89). A positive correlation was found between the IL-8 levels and the duration of gutka chewing (r=-0.64, P<0.01). Conclusions: Gutka chewing leads to increased gingival RC and clinical loss of attachment. There was no effect seen in the proinflammatory cytokine levels in the GCF of gutka users.

• 구강회복응용과학지
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• 제32권3호
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• pp.149-157
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• 2016

성공적인 라미네이트 치료를 위해서는 치아형성 방법이 매우 중요하다. 법랑질에 국한된 보존적인 치아형성, 치태조절이 용이한 치은연선상(equigingival) 변연, 가능한 존재하는 접촉점의 유지 등의 조건이 일반적으로 알려져 있으나 구체적인 치아형성 디자인에 관하여는 논쟁의 여지가 존재한다. 생역학적으로 고려해볼 때, 다음과 같은 사항들이 추천된다. 절단면 피개는 심미적 요구와 전방유도의 재설정 필요 여부 측면에서 결정해야 하며, 법랑질 두께가 충분한 경우에는 구개측 연장을 하는 것이 좋으나 응력 집중이 큰 구개오목(palatal concavity)에 변연이 위치하는 것은 부적절하다. 인접면 연장은 증례에 따라 선택적으로 시행하며, 인접면에 레진수복물이 존재하는 경우에는 표면처리 후 레진 수복물을 절반 이상 피개하는 형태의 라미네이트로 수복한다. 변색이 심하지 않은 근관치료가 시행된 치아의 경우 라미네이트 수복을 고려해 볼 수 있으며, 이 때 섬유강화레진 포스트를 사용하는 것을 추천한다.

• The Journal of Advanced Prosthodontics
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• 제7권6호
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• pp.468-474
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• 2015

PURPOSE. The aim of this study was to characterize and compare bacterial diversity on the removable partial denture (RPD) framework over time. MATERIALS AND METHODS. This descriptive pilot study included five women who were rehabilitated with free-end mandibular RPD. The biofilm on T-bar clasps were collected 1 week ($t_1$) and 4 months ($t_2$) after the RPD was inserted ($t_0$). Bacterial 16S rDNA was extracted and PCR amplified. Amplicons were cloned; clones were submitted to cycle sequencing, and sequences were compared with GenBank (98% similarity). RESULTS. A total of 180 sequences with more than 499 bp were obtained. Two phylogenetic trees with 84 ($t_1$) and 96 ($t_2$) clones represented the bacteria biofilm at the RPD. About 93% of the obtained phylotypes fell into 25 known species for $t_1$ and 17 for $t_2$, which were grouped in 5 phyla: Firmicutes ($t_1=82%$; $t_2=60%$), Actinobacteria ($t_1=5%$; $t_2=10%$), Bacteroidetes ($t_1=2%$; $t_2=6%$), Proteobacteria ($t_1=10%$; $t_2=15%$) and Fusobacteria ($t_1=1%$; $t_2=8%$). The libraries also include 3 novel phylotypes for $t_1$ and 11 for $t_2$. Library $t_2$ differs from $t_1$ (P=.004); $t_1$ is a subset of the $t_2$ (P=.052). Periodontal pathogens, such as F. nucleatum, were more prevalent in $t_2$. CONCLUSION. The biofilm composition of the RPD metal clasps changed along time after RPD wearing. The RPD framework may act as a reservoir for potentially pathogenic bacteria and the RPD wearers may benefit from regular follow-up visits and strategies on prosthesis-related oral health instructions.

• 대한미생물학회지
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• 제22권3호
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• pp.309-321
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• 1987

For the investigation of microbiological and immunological specificity of Bacteroides gingivalis, Bacteroides gingivalis were isolated, enumerated and characterized from 13 Korean rapidly progressive periodontitis and 7 healthy control by anaerobic culture technique. The total proportion of black-pigmented Bacteroides from Korean R.P.P. patients and healthy control were 8.78% and 0.92%, respectively, among total isolated black-pigmented Bacteroides. In antibiotic susceptibility test, Bacteroides gingivalis isolated from R.P.P. patients were sensitive to Ampicillin and Tetracycline, and resistant to Gentamicin and Erythromycin in disc diffusion method. In antibiotic broth dilution method, the minimum inhibitory concentration(MIC) to Bacteroides gingivalis was 2 unit/ml of Penicillin and $0.25{\sim}1{\mu}g/ml$ of Tetracycline, respectively. The concentration of serum IgG in rapidly progressive periodontitis patients were sigificantly higher than that of healthy control, and concentration of diluted gingival crevicular IgG has not any significant differences between two groups. Serum and gingival crevicular IgG antibody to Bacteroides gingivalis were significantly higher titer in rapidly progressive periodontitis patients to compare with healthy control. The lipopolysaccharide profiles of 2 Korean B. gingivalis in silver stained sodium dodecyl sulfate-polyacrylamide gel electrophoresis were similar to type strains of B. gingivalis and typical LPS band were appeared around the 24-Kd molecular weight. Immunodiffusion test and immunoelectrophoresis of the L.P.S. extracted from 2 Korean B. gingivalis and 2 kinds of type strains of B. gingivalis showed that B. gingivalis Korean-1 was reacted identically to B. gingivalis ATCC 33277. In trypsin and ${\alpha}$-glucosidase activity test of 2 Korean B. gingivalis, both of them revealed positive trypsin and negative ${\alpha}$-glucosidase activity, respectively. These investigation suggested that B. gingivalis is important pathogenic plaque bacteria for the pathogenesis of periodontitis and further study is needed to purify and characterize of the species-specific antigens of this organisms to develop monoclonal antibody and potential diagnostic reagents.