• International Journal of Oral Biology
• /
• v.36 no.4
• /
• pp.187-194
• /
• 2011

Periodontitis is an inflammatory disorder of the periodontium, characterized by destruction of the tooth supporting tissues including alveolar bone and mediated by various pro-inflammatory mediators. Here, we demonstrated that HP08-0106, composed of four crude drugs-Gardenia jasminoides Grandiflora, Angelica gigas Nakai, Rehmannia glutinosa, and Schizonepeta tenuifolia in a weight ratio of 2:2:1:2, perturbs inflammatory responses, osteoclast formation in LPS-induced RAW 264.7 cells and alveolar bone resorption in ligature-induced periodontitis. HP08-0106 decreased the protein level of iNOS and COX2 as well as the secreted level of IL-$1{\beta}$, indicating that HP08-0106 has antiinflammatory effects. HP08-0106 also inhibited the expression of genes associated with osteoclastogenesis including c-Fos, MMP-9 and TRAP. Moreover, HP08-0106 exhibited a protective effect from alveolar bone loss in ligature-induced periodontitis animal models. Our results strongly suggest that HP08-0106 represent an important therapeutic tool to treat inflammatory disorders associated with bone loss such as periodontitis.

• Journal of Periodontal and Implant Science
• /
• v.43 no.4
• /
• pp.147-152
• /
• 2013

Purpose: An animal periodontitis model is essential for research on the pathogenesis and treatment of periodontal disease. In this study, we have introduced a lipopolysaccharide (LPS) of a periodontal pathogen to the alveolar bone defect of experimental animals and investigated its suitability as a periodontitis model. Methods: Alveolar bone defects were made in both sides of the mandibular third premolar region of nine beagle dogs. Then, the animals were divided into the following groups: silk ligature tied on the cervical region of tooth group, Porphyromonas gingivalis LPS (P.g. LPS)-saturated collagen with silk ligature group, and no ligature or P.g. LPS application group as the control. The plaque index and gingival index were measured at 0 and 4 weeks postoperatively. The animals were then euthanized and prepared for histologic evaluation. Results: The silk ligature group and P.g. LPS with silk ligature group showed a significantly higher plaque index at 4 weeks compared to the control (P<0.05). No significant difference was found in the plaque index between the silk ligature group and P.g. LPS with silk ligature group. The P.g. LPS with silk ligature group showed a significantly higher gingival index compared to the silk ligature group or the control at 4 weeks (P<0.05). Histologic examination presented increased inflammatory cell infiltration in the gingival tissue and alveolar bone of the P.g. LPS with silk ligature group. Conclusions: An additional P.g. LPS-saturated collagen with silk ligature ensured periodontal inflammation at 4 weeks. Therefore, P.g. LPS with silk ligature application to surgically created alveolar bone defects may be a candidate model for experimental periodontitis.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.44 no.2
• /
• pp.138-146
• /
• 2017

The aim of this study was to estimate time of biomineralization in developmental stages of rat lower incisors. Eruption length was measured. Four stages of incisor development were identified on histologic and microscopic computerized tomography (micro-CT) sections: (1) preodontoblast, (2) dentin matrix secretion, (3) enamel matrix secretion, and (4) enamel calcification. The overall eruption rate of the rat lower incisor was $600{\pm}70{\mu}m/day$ ($mean{\pm}SD$; n = 12). The length of the enamel secretion was $4.59{\pm}0.75mm$ in histologic section, was $3.64{\pm}0.63mm$ in radiographic section, which converts to $180.4{\pm}30.0hours$, $145{\pm}25hours$ respectively (n = 24). These findings suggested that the four biomineralizing developmental stages of the rat incisor took only several days. The significance of this animal study was to provide understanding for the rapid biomineralization process of developing rat tooth germ by analysis of tooth forming period.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.31 no.5
• /
• pp.856-861
• /
• 2002

It has been reported in animal and human studies that green tea shows a health protective characteristics. In the present study, we investigated the disease prevalence according to chronic green tea consumption in 92 subjects (mean age: 59.548.9, men: 41, women: 51) living in green tea cultivation village. The consumption of green tea and other life-style characteristics were ascertained by a questionnaire. The subjects were divided into three groups according to the period of green tea consumption (0, < 10 year, and $\geq$ 10 year). For green tea consumption groups, most of the subjects have been drinking green tea in order to protect disease and recognized the effects of green tea as detoxification of alcohol and smoking, protection of cold or release from fatigue. There were no significant differences in drinking and smoking, physical activity, and a cold prevalence among the groups. Green tea consumption was associated with lower levels of prevalence of tooth decay as well as the osteoporosis. The score of dietary habits was higher by increasing green tea consumption period (p<0.05). Consequently, chronic green tea consumption can be considerably effective in health promotion.

• Animal Systematics, Evolution and Diversity
• /
• v.20 no.2
• /
• pp.179-184
• /
• 2004

Some hydromedusae were collected from the East Sea ($36^{\circ}$30'124'N and $130^{\circ}$06'446'E), Yousu and Youngkwang with horizontal plankton net during from Nov. 2001 to Dec. 2002. They were identified into Proboscidactyla flavicirrata in the order Limnomedusae, and Muggiaea bargmannae and Diphyes bojani in the suborder Calycophorae of the order Siphonophora, respectively. P. flavicirrata is similar with P. stellata in the shape and size, but it is distinguished from later species in that P. stellata has six radial canals, 24 short marginal tentacles and dichotomous branching pattern. The suborder Calycophorae is the first recorded in Korea and posseses only develop a nectosome. In Muggiaea bargmannae, anterior nectophore is simillar with Dimophyes arctica in the shape of nectophore, but it is distinguished from the later in that D. arctica has a undivided mouth plate and deeper hydroecium. In Diphyes bojani, anterior nectophore is simillar with Diphyes dispar in the shape of nectophore, but it is distinguished from the later in which D. dispar has a deeper hydroecium and more prominant dorsal tooth. No posterior nectophores of Muggiaea bargmannae and Diphyes bojani have been observed.

• Journal of the Korea Convergence Society
• /
• v.2 no.4
• /
• pp.47-52
• /
• 2011

Periodontal disease is a common inflammatory disorder that is being considered as a risk factor for atherosclerotic complication. Recent epidemiological evidence also supports that its potential association with increased blood pressure levels and hypertensive prevalence. Data from cross-sectional studies suggest that in hypertensive patients periodontal disease may enhance the risk and degree of target organ damage. So dental infections have been associated with cardiovascular diseases. There are potential pathophysiologic links between hypertension and periodontits. The role of the inflammatory pathway include C-reactive protein(CRP). CRP is an inflammatory mediator that has been shown to predict the development of hypertension independently of baseline BP and traditional risk factors, has been consistently reported as at least mildly elevated in patients with periodontal disease. Reactive oxygen species produced by locally infiltrating neutrophils participate in periodontal tissue destruction. Periodontits can lead to inflammatory responses in the atrial myocardium, which disturbs the structural and electrophysiologic properties of the atrium and facilitates atrial fibrillation in the animal experiment.

• International Journal of Oral Biology
• /
• v.37 no.2
• /
• pp.63-68
• /
• 2012

It has been documented that SPA0355 exerts antiinflammatory effects via the inhibition of nuclear factor-kappaB activation. In present study, we investigated the inhibitory effects of SPA0355 on periodontitis in an animal model. Periodontitis was induced by ligation of the cervix of the 1st molar in the left mandible in rats. After ligature, the rats were randomly divided into four groups and topically applied with SPA0355 (0.5, 1, and 2%) or the vehicle alone once daily for 10 days. Body weight and food intake were measured daily throughout the experimental period. At day 10 post-ligature, the infiltration of inflammatory cells and distance of the cementoenamel junction (CEJ) to the alveolar bone crest (ABC) in the distal area of ligatured tooth were estimated histopathologically. No changes in body weight or food intake were found between the control and SPA0355 groups. The degree of inflammation was decreased in all three SPA0355 application groups. A decrease CEJ-ABC distance was observed in the 0.5% and 1% SPA0355 groups. These results indicate that SPA0355 inhibits the infiltration of inflammatory cells and alveolar bone resorption and suggests its potential as a therapeutic agent for periodontitis.

• Journal of Periodontal and Implant Science
• /
• v.46 no.5
• /
• pp.291-302
• /
• 2016

Purpose: The aim of the present study was to evaluate the effectiveness of using a mineralized bone cortical allograft (MBCA), with or without a resorbable collagenous membrane derived from bovine pericardium, on alveolar bone remodeling after immediate implant placement in a dog model. Methods: Six mongrel dogs were included. The test and control sites were randomly selected. Four biradicular premolars were extracted from the mandible. In control sites, implants without an allograft or membrane were placed immediately in the fresh extraction sockets. In the test sites, an MBCA was placed to fill the gap between the bone socket wall and implant, with or without a resorbable collagenous membrane. Specimens were collected after 1 and 3 months. The amount of residual particles and new bone quality were evaluated by histomorphometry. Results: Few residual graft particles were observed to be closely embedded in the new bone without any contact with the implant surface. The allograft combined with a resorbable collagen membrane limited the resorption of the buccal wall in height and width. The histological quality of the new bone was equivalent to that of the original bone. The MBCA improved the quality of new bone formation, with few residual particles observed at 3 months. Conclusions: The preliminary results of this animal study indicate a real benefit in obtaining new bone as well as in enhancing osseointegration due to the high resorbability of cortical allograft particles, in comparison to the results of xenografts or other biomaterials (mineralized or demineralized cancellous allografts) that have been presented in the literature. Furthermore, the use of an MBCA combined with a collagen membrane in extraction and immediate implant placement limited the extent of post-extraction resorption.

• International Journal of Oral Biology
• /
• v.38 no.3
• /
• pp.87-92
• /
• 2013

Periodontal inflammation increases the risk of tooth loss, particularly in cases where there is an associated loss of alveolar bone and periodontal ligament (PDL). Histological and morphometric evaluation of periodontal inflammation is difficult. Especially, the lengths of the periodontal ligament and interdental alveolar bone space have not been quantified. A quantitative imaging procedure applicable to an animal model would be an important clinical study. The purpose of this study was to quantify the loss of alveolar bone and periodontal ligament by evaluation with micro-computed tomography (micro-CT). Another purpose was to investigate differences in infections with systemic E. coli LPS and TNF-${\alpha}$ on E. coli lipopolysaccharide (LPS) in loss of alveolar bone and periodontal ligament model on mice. This study showed that linear measurements of alveolar bone loss were represented with an increasing trend of the periodontal ligament length and interdental alveolar process space. The effects of systemic E. coli LPS and TNF-${\alpha}$ on an E. coli LPS-induced periodontitis mice model were investigated in this research. Loss of periodontal ligament and alveolar bone were evaluated by micro-computed tomography (micro-CT) and calculated by the two- and three dimensional microstructure morphometric parameters. Also, there was a significantly increasing trend of the interdental alveolar process space in E. coli LPS and TNF-${\alpha}$ on E. coli LPS compared to PBS. And E. coli LPS and TNF-${\alpha}$ on E. coli LPS had a slightly increasing trend of the periodontal ligament length. The increasing trend of TNF-${\alpha}$ on the LPS-induced mice model in this experiment supports the previous studies on the contribution of periodontal diseases in the pathogenesis of systemic diseases. Also, our findings offer a unique model for the study of the role of LPS-induced TNF-${\alpha}$ in systemic and chronic local inflammatory processes and inflammatory diseases. In this study, we performed rapidly quantification of the periodontal inflammatory processes and periodontal bone loss using micro-computed tomography (micro-CT) in mice.

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