Biological Activities of Calcium Polyphosphate / 대한치주과학회지

No abstract available.

The Frequency of Detecting Prevotella intermedia and Prevotella nigrescens in Korean Adult Periodontitis Patients / 대한치주과학회지

Prevotella intermedia has been implicated as a potent pathogen in many kinds of periodontal, pulpal and periapical diseases. However, it has been isolated from periodontally healthy adults and from edentulous children as well. The intraspecies heterogeneity of Prevotella intermedia has been demonstrated in early studies and finally Shah & Gharbia confirmed the existence of 2 DNA homology groups and proposed dividing Prevotella intermedia into 2 species, Prevotella intermedia and Prevotella nigrescens. This study was designed to examine the frequency of Prevotella intermedia and Prevotella nigrescens in diseased periodontal pockets and healthy gingival sulcus of Korean people by PCR based on 16s ribosomal DNA sequence. One hundred adults who had adult periodontitis but not taken any periodontal treatment or antibiotics during previous 6 months and 50 adults who had healthy periodontal tissue were selected for this study. The sulcular fluid was collected into VMGA by sterilized paper point and diluted to 1,000 times in anaerobic chamber. 100ml of sample was cultured in 37degrees C for 10 days. Among the bacterial colonies, BPB were selected and cultured in BHI broth and then Prevotella intermedia was identified through Gram staining and biochemical test. Identified Prevotella intermedia was cultured again and centrifuged. DNA was extracted from the pellet using several reagents. PCR was performed by previously designed primer. The results were followed. 1.BPB were isolated from 39 of 100 samples of diseased periodontal pockets(39%). 2.Prevotella intermedia was identified from 24 of 39 BPB samples. 3.Among 24 Prevotella intermedia, 21 were confirmed as Prevotella intermedia(87.5) and 2 were confirmed as Prevotella nigrescens(8.33%). 4.BPB were isolated from 9 of 50 samples of periodontally healthy patients. Among them only two were identified as Prevotella intermedia, that is, one was confirmed as Prevotella intermedia and the other was Prevotella nigrescens.

Antibacterial Effects and Cytotoxicity of Crassirhizomae Rhizoma / 대한치주과학회지

The purpose of this study was to evaluate the antimicrobial activity of Crassirhzimae rhizoma and its possible use as an oral antiseptics for prevention of periodontitis. Its antibacterial activity against periodontopathic microorganisms including Actinobacillus actiomycetemcomitans, Capnocytophaga ochracea, Streptococcus mutans, Porphyromonas gingivalis, Prevotella intermedia, Actinomyces viscosus, Fusobacterium nucleatumwas evaluated via modified stab culture method. The cytotoxicity against gingival fibroblasts and rat osteoblasts was investigated via [3H]thymidine incorporation and cellular activity was investigated via MTT assay. Chlorhexidine was used as control group. Crassirhizomae rhizoma was prepared at concentrations of 0.2, 0.15, 0.1, 0.05%. Chlorhexidine was also prepared at the same concentration. Crassirhizomae rhizoma showed lower antimicrobial antivity against these microorganism than chlorhexidine, but this difference was not significant. And, Crassirhzomae rhizoma showed more cellular activity and less cytotoxicity than chlorhexidine on human gingival fibrablast and rat osteoblast. This study suggests that Crassirhzomae rhizoma might be a candidate for a safe oral antiseptic for the prevention and treatment of periodontal disease.

Relationship between Preterm Low Birth Weight and Periodontal Disease Activity in Pregnancy / 대한치주과학회지

PURPOSE We designed this study for the purpose of determining the relationship between periodontal disease activity and PLBW, using the evaluation of probing pocket depth, loss of attachment, gingival index, gingival crevicular fluid amount and subgingival microflora. METHODS A total of 100 volunteer mothers(mean age 30.44) at the Department of Obstetrics and Gynecology Seoul National University Hospital were selected for this study.Pregnancy outcomes were categorized into cases and controls in two ways. our definition was based on the following; Group 1 : Any PLBW cases Vs. All NBW controls Group 2 : PLBW cases Vs. NBW controls A periodontal exam was performed on the Ramfjord(#16, 21, 24, 36, 41, 44) teeth and Clinical evaluation consisted of probing pocket depth, loss of attachment, gingival index and gingival crevicular fluid amount. Subgingival plaque samples were collected by three sterile #35 paper points. The total number of anaerobic colonies and aerobic bacteria were enumerated after incubation. Antisera to P. gingivalis, P. intermedia, A. actinomycetemcomitans were produced in white rabbits with live whole cells suspensions. The specific fluorescent bacteria obtained by immunofluorescence and total cell counts obtained by dark-field microscopy were counted on four fields. The percent of each specific microorganism in the total cell count was determined. RESULTS Any PLBW and PLBW cases showed significantly greater probing depth and attachment loss than all NBW and NBW controls. Cases group had significantly increased anaerobic bacterial counts compared with control group and no differences in the other microbes. This study confirmed that periodontal disease is a statistically significant risk factor for PLBW by investigating clinical parameters and subgingival plaque analysis.

The Effect of TitaniumI Surface Treatment on Osteoblast-Like Cell Attachment and Proliferation / 대한치주과학회지

In clinical therapy, the current goal of dental implants is to enhance quantity and quality of osseointegration. Surface roughness and oxide structure are considered to influence the behavior of adherent cells. The purpose of this study is to evaluate the effect of different surface treatment on cellular response. The attachment and proliferation of osteoblast-like cell on sandblasted, sandblasted and etched, thermal oxidated surfaces have been compared. Sandblasting was done with Al2O3 particles(grain size of 50micrometer), etching was processed with NH4OH : H2O2 : H2O(1:1:5) at 90degrees C for 1 minute. Thermal oxidation was followed sandblasting and etching at 400degrees C, 600degrees C, 800degrees C for 2 hours. Measurement of surface roughness after the different treatment did not show any differences of Ra value between terated surfaces. Cell attachment and proliferation were increased during experiment period, but no difference was observed. SEM evaluation revealed a similar pattern of osteoblastlike cells, well attached with dendritic extension and producing numerous matrix vesicles on cell surface. The results of this study showed that oxide layer alteration by thermal oxidation did not affect the attachment and proliferation of osteoblast-like cells. This suggests the possibility that the cellular responses are further influenced by surface roughness than titaniun oxide structure. This study was supported by a grant(HMP-98-G-2-035-B) of the HAN(highly advanced National) Projected, Ministry of Health & Welfare, R.O.K