• International Journal of Oral Biology
• /
• 제37권3호
• /
• pp.85-90
• /
• 2012

Periodontal disease induces an increased incidence of tooth loss, particularly in cases with an associated loss of alveolar bone and periodontal ligaments. In this study, alveolar bone loss was detected by micro-computed tomography (CT) following exposure to E. coli lipopolysaccharide (LPS) in a streptozotocin (STZ)-induced diabetic mouse model. A 10 mg/ml dosage of E. coli LPS was applied between the first, second and third molars of the mice three times a week for 10 weeks. The loss of periodontal ligaments and alveolar processes was then evaluated by micro-CT using two and three dimensional microstructure morphometric parameters. In the diabetic mice, E. coli LPS induced the destruction of periodontal ligaments and loss of alveolar process spaces. The distances between periodontal ligaments were significantly widened in the STZ-LPS group compared with the untreated STZ group. The 10 mg/ml exposure to E. coli LPS in the STZ mice also resulted in a significant decrease in the alveolar bone volume fraction. The results of our study suggest that alveolar bone loss can be readily detected by volumetric micro-CT analysis as an increase in the distance between periodontal ligaments and in the alveolar process length.

• 대한치과교정학회지
• /
• 제9권1호
• /
• pp.9-14
• /
• 1979

The purpose of this study was to pursue the biosynthesis of proteins of human and bovine periodontal ligaments in vitro system. The excised periodontal ligaments from human and bovine were incubated in Krebs-glucose medium containing $^3H$-proline. After incubation the incubated periodontal ligaments were homogenized and the proteins were treated with 0.1%sodium dodecyl sulfate and $\beta$-mercaptoethanol. Separation of the protein fractions was performed with agarose gel column chromatography and SDS acrylamide gel electrophoresis. The results indicated as follow: 1. Only a small percentage of $^3H$-proline incorporated into proteins was hydroxylated to $^3H$-hydroxyproline. 2. The labeled proteins in periodontal ligaments showed a wide distribution of molecular weight. But only small amounts of labeled protein were found that were characteristics of the molecular weight of collagen. 3. In all of the combined fractions of gel filtration, the degree of hydroxylation was small.

• 대한치과보철학회지
• /
• 제9권1호
• /
• pp.17-22
• /
• 1969

Intra-oral films of 155 patients were taken on the areas of Gold Crown-Bridges, S. P. Bridges and Partial Dentures. And the author observed periodontal ligaments widening rates, the presence of periapical lesions and the alveolar bone patterns on the Partial Denture Saddle portions. The results were as follows : 1. Periodontal ligaments a) Periodontal ligaments widening rate increased obviously with the duration of wearing those prosthetic appliances. b) Periodontal ligaments widening rate was the highest in partial denture wearing patients, and then that of S. P. Crown Bridge patients, Gold Crown Bridge wearing females, Gold Crown Bridge males were the sequences. 2. Periapical lesions a) Periapical lesions increased with the wearing duration of those prosthetic appliances. But they did not increase in proportion to the duration. Periapical lesions were about the same in the teeth with those appliances showing relatively higher rate in Partial Denture abutment teeth and the lowest in Gold-Bridge abutment teeth. 3. Alveolar bone of Partial Denture saddle portion One third of all(32%) were normal with their smooth and compact bone pattern so that they were considered to perform normal function.

• 대한치과교정학회지
• /
• 제19권1호
• /
• pp.21-44
• /
• 1989

Incipient changes of the periodontal tissue in the pressure zones of rat molar subjected to the experimental force were studied by the transmission electron microscope. Experimental animals were consisted in 3 control and 21 experimental rats, of which one maxillary first molar was moved buccally with a fixed appliance which were exerting the force of 15 gm. After experimental period of 1 hour, 3 hours, 6 hours, 24 hours, 2 days, 3 days and 7 days, the animal were sacrificed with cardiac perfusion of $2.5\%$ glutaraldehyde in the sodium cacodylate buffer and the experimental teeth with surrounding periodontal structures were processed for electron microscope. At the beginning of the tooth movement, periodontal ligaments of the pressure were compressed and collagenous fibers were arranged parallel to the root of the teeth and cell free zones in company with cell necrosis were followed. Cell free zones at the periodontal ligaments appeared in the 3 hour survival group, and getting severe with time lapse it became widespread in 2-3 day survival group and undermining bone resorption as a healing process was observed in 7 day survival group. Dilatation of mitochondria and swelling of the rER in the fibroblast and other connective tissue cells in the periodontal ligament were observed in the 3 hour survival group, which were characteristics of the incipient changes in the compressed periodontal ligament. Dilatation of nuclear membrane and pyknosis were followed by the destruction of the nucleus and cell membrane. There were no evidence in cell damage or necrosis of the alveolar bone adjacent to the hyalinized area of periodontal ligaments.

• Restorative Dentistry and Endodontics
• /
• 제38권4호
• /
• pp.194-203
• /
• 2013

Objectives: To investigate the effect of enamel matrix derivative (EMD) on periodontal healing of replanted teeth in animal models. Materials and Methods: The authors searched MEDLINE, PubMed, EMBASE, Cochrane Library, Web of Knowledge and Scopus for articles published up to Oct 2012. Animal studies in which EMD was applied in transplanted or replanted teeth with adequate controls and histological data were considered. Normal periodontal healing or root resorption determined by histology after EMD was applied in replanted teeth with adequate controls was used as outcome measures. The following search strategy was used: ('Emdogain' OR 'enamel matrix proteins' OR 'enamel matrix derivative') AND ('avulsion' OR 'transplantion' OR 'autotransplantation' OR 'replantation'). Results: Six animal studies were included in the final review. There was great heterogeneity in study design among included studies. Two studies with similar study designs were identified and analyzed by a meta-analysis. The pooled estimates showed a significantly higher normal healing and surface resorption and significantly less inflammatory and replacement resorption in EMD-treated groups compared with non-EMD-treated groups. Conclusions: With the limitations of this systematic review, the use of EMD led to greater normal periodontal healing and surface root resorption and less inflammatory and replacement root resorption in the presence of periodontal ligaments. However, no definite conclusion could be drawn with regard to the effect of EMD on periodontal healing and root resorption when no periodontal ligaments exist.

• 대한치과교정학회지
• /
• 제11권2호
• /
• pp.65-70
• /
• 1981

In the present study orthodontic force was applied to the molars of control group and experimental group treated with the lathyrogen beta-aminopropionitrile (BAPN). Observation resulted in the following conclusions : 1) New alveolar bone formation in response to orthodontic force in BAPN-treated rats exceeded corresponding bone formation in control of cup when measured at two tension sites in the periodontal ligament. 2) BAPN administration produced disorganization of the collagenous fibers of the periodontium of experimental group. Multiple eosinophilic cell-free areas were found distributed throughout the radicular portions of affected periodontal ligaments. 3) The areas of periodontium surrounding orthodontically treated teeth exhibited relatively normal organization under these conditions, while the periodontium of adjacent nonorthodontically treated teeth was disorganized. 4) The present results suggest that the typical histologic response to orthodontic force application can occur in the presence of a chemically and physically altered periodontium.

• Restorative Dentistry and Endodontics
• /
• 제25권3호
• /
• pp.338-358
• /
• 2000

The effect of bench drying or removal of the periodontal ligament with NaOCl upon periodontal healing and root resorption after replantation of molars was studied in rats. A total of 40 Sprague-Dawley female rats were used and fed a powdered purina rat chow diet containing 0.4% beta-aminoproprionitrile. The maxillary first molars were extracted and the periodontal ligaments were removed either by bench drying for 15 minutes or by immersion in 2.5% NaOCl solution. The rats were sacrificed at 5, 10, and 21 days by heart infusion. In order to observe the effect of 0.5% stannous fluoride, $10^{-4}M$, $10^{-2}M$, and 1M etidronate disodium on the early stage of periodontal healing, the periodontal ligament was removed with 2.5% NaOCl followed by immersion of the molar in the respective solutions for 5 minutes. The rats were sacrificed after 10 days and the following results were obtained. 1. The removal of the periodontal ligament with 2.5% NaOCl seemed to be more effective than bench drying, since the resorption area in the NaOCl treated group showed a gradual increase whereas a decline in resorption area from 5 days to 21 days was observed in the bench dried group. 2. The application of 0.5% stannous fluoride seemed to enhance the periodontal ligament attachment and active migration of fibroblasts could be observed. 3. The application of $10^{-4}M$, $10^{-2}M$, and 1M etidronate disodium led to a good periodontal ligament attachment. No evident areas of root resorption were found. 4. The use of ${\beta}$-APN made it possible to extract the maxillary first molar with all five roots intact.

• Journal of Periodontal and Implant Science
• /
• 제26권1호
• /
• pp.188-201
• /
• 1996

One of the initial events required for periodontal regeneration is the attachment, spreading and proliferation of fibroblasts at the healing sites. These have been reported that minocycline stimulates the attachment of gingival fibroblasts and periodontal ligament cells and $TGF-{\beta}1$ enhances the proliferation of periodontal ligament cells. The purpose of this study was to evaluate and confirm the effect of minocycline and $TGF-{\beta}1$ on human gingival fibroblasts and periodontal ligament cells. That gingival fibroblasts and periodontal ligament cells used in this study were obtained from the explants of healthy periodontal ligaments and gingival tissues of extracted 3rd molars or premolar teeth extracted from the patients with orthodontic treatment. The cells were cultured in ${\alpha}-MEM$(minimal essential medium) supplemented with antibiotics and FBS(fetal bovine serum) at $37^{\circ}C$ in a humidified atmosphere of 5% carbon dioxide-95% air. Cells were used between the 5th to 8th passage in this study. The attachment and activity of both cells were evaluated by MTT assay. The results were as follows: 1. Maximum gingival fibroblast attachment was seen at a $50{\mu}g/ml$ dose of minocycline, while maximum periodontal ligament cell attachment was seen at a $100{\mu}g/ml$, and exposure of both cells to minocycline above maximal attachment dose results in a decline from maximum attachment. 2. The activity values of both cells tested minocycline were below to the control activity values at all concentrations. 3. The attachment values of both cells tested $TGF-{\beta}1$ were below or similar to control attachment values. On the above the findings, minocycline stimulated the cell attachment of gingival fibroblasts and periodontal ligament cells and $TGF-{\beta}1$ enhances the cell activity of periodontal ligament cells.

• Journal of Periodontal and Implant Science
• /
• 제27권2호
• /
• pp.347-361
• /
• 1997

The present study investigates the effects of DFDB graft combined with Calcium sulfate membrane on the periodontal wound healing in dehiscence defects of dogs. Following the initiation of general anesthesia by I.V. administration of 30mg/kg of pentobarbital, first premolar was extracted and full-thickness flap was elevated from the second to the fourth premolar. The portion of premolars coronal to the alveolar crest was removed and mesial and distal roots separated to produce single rooted teeth. Exposed root canals were sealed with Caviton and covered completely with flaps sutured. Following the healing period of 12 weeks, the surgical sites were uncovered and $4{\times}4mm$ dehiscence defects were surgically created. Those defects with DFDB graft combined with Calcium sulfate membrane following root planing, were designated as test sites and those with flap surgery-only were designated as controls. 1. No foreign-body reaction or inflammation were observed in either groups. Calcium sulfate was completely resorbed in the test sites. 2. Significantly greater amounts of new cementum was observed in test sites compared with the controls. Significant amounts of functionally orientated collagens were observed in the test sites. 3. New bone formation was observed in significantly greater amounts in test sites. The results suggest that combined graft of DFDB and calcium sulfate is extremely biocompatible with a potential for new bone and cementum formation, and functional alignment of periodontal ligaments.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제32권5호
• /
• pp.426-429
• /
• 2006

The fibroblast in the periodontal ligaments received various stress. Among them, compression and tension are quite important and they are related to the remodeling of tooth and alveolar bone. We studied the change of expression of interleukin-6 (IL-6) and interleukin-8 (IL-8) in the fibroblasts of the periodontal ligaments by real-time RT-PCR and ELISA. In results, the relative activity of IL-6 mRNA in 2 hours after was 1.54${\pm}$0.08 and 1.00${\pm}$0.05 in control and test, respectively (P<0.05). Its 12 hours after was 1.23${\pm}$0.06 and 2.78${\pm}$0.14 in control and test, respectively (P<0.05). The relative activity of IL-8 mRNA in 2 hours after was 1.00${\pm}$0.05 and 0.24${\pm}$0.01 in control and test, respectively (P<0.05). Its 12 hours after was 1.23${\pm}$0.06 and 0.63${\pm}$0.03 in control and test, respectively (P<0.05). The concentration of IL-6 was 1.02${\pm}$0.16 ng/ml, 0.90${\pm}$0.14 ng/ml, and 1.32${\pm}$0.12 ng/ml (P<0.05) in control, 2, and 12 hours after, respectively. The concentration of IL-8 was 2.26${\pm}$0.17 ng/ml, 1.70${\pm}$0.26 ng/ml (P<0.05), and 0.84${\pm}$0.47 ng/ml (P<0.05) in control, 2, and 12 hours after, respectively. In conclusion, the expression of IL-6 was significantly increased after the application of the static compressive force, but IL-8 was significantly decreased. Considering their known function, their expression is quite important in tooth and bone resorption.