• 대한소아치과학회지
• /
• 제39권2호
• /
• pp.174-180
• /
• 2012

성장 중인 아동에서는 치근의 성장이 계속됨에 따라 치수가 괴사되어 치근의 병변이 있는 미성숙 영구치에서도 치수의 재혈관화가 실제로 일어날 수 있다는 가능성이 제시 되고 있다. 치수의 재혈관화를 위해서는 근관 내의 감염의 조절과 함께 적절한 scaffold가 필요하며, platelet-rich plasma(PRP)가 이상적인 scaffold로 제시되었다. 최근 임상에서는 PRP의 단점을 극복한 platelet-rich fibrin(PRF)가 응용되고 있다. 본 증례에서는 치외치의 교두 파절로 인한 치수 감염으로 치근단 병변을 가진 미성숙 영구치의 근관 내에 ciprofloxacin, metronidazole, minocycline의 세 가지 항생제 적용 후 이와 함께 PRF를 적용하였다. 정기적인 검진 결과 치근단 병변의 치유와 함께 치근 성장이 관찰되었다. 이러한 보존적인 근관 치료는 미성숙 영구치에서 치근단 형성술의 대안적인 치료로서 이용될 수 있을 것이며, 향후 장기간의 임상적 관찰이 필요할 것이다.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제27권3호
• /
• pp.238-247
• /
• 2005

The placement of different graft materials and/or the use of occlusive membranes to cover the extraction socket entrance are techniques aimed at reducing alveolar ridge resorption and enhancing bone formation. However, in spite of its clinical advantage, the use of graft materials in fresh extraction socket has been questioned because particles of the grafted material have been found in alveolar sockets with fibrous union. The purposes of this study were to evaluate whether alveolar ridge resorption following tooth extraction could be reduced and bone formation could be enhanced by the application of absorbable gelatin spongy or gelatin spongy soaked with platelet rich plasma(PRP) used as a space filler in clinical and radiographic aspects. Eighty patients who were scheduled for extraction of both third molars were participated and carried out by one experienced surgeon. Following extraction of teeth, one extracted socket were treated with gelatin spongy as an experimental group A and the other were treated with gelatin spongy and PRP as an experimental group B. The routine extracted socket were healed without any treatment as a control group. From the period of extraction to 12 weeks postoperatively, we examined the clinical course and radiographic evaluation on socket at regular interval. Both experimental groups showed faster wound healing process than control clinically. Vertical gingival height of the extraction socket were less changed statistically in both experimental groups than control. The horizontal width change of the extraction socket were not significant statistically in any group. Radiographic changes of the alveolar bone height were less changed in both experimental groups and bone density were showed higher than control. There were a little difference between experimental group A and B. In conclusion, absorbable gelatin sponge and with PRP were considered as having preservation effects of extraction socket and stimulation of bone formation process after extraction.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제30권2호
• /
• pp.158-164
• /
• 2008

Purpose : Recently, various materials were developed for enhancing bone formation capacity. Platelet rich plasma(PRP) is an autologous source with several growth factors and obtained by sequestering and concentrating platelets by gradient density centrifugation. This study was to evaluate the effect of PRP on healing of grafted bone. Materials and methods : Two blood samples were obtained and analysed for measuring platelet counts of normal blood and PRP. In experimental group, two defects of mandibular bone, 10mm in diameter and 4.0mm deep, were created in the mandible and immediately grafted with autogenous bone chips mixed with PRP. In control group, same bone defects were prepared and grafted with autogenous bone chips. Gelform was used for carrier of PRP. 2 weeks, 4 weeks, 8 weeks later, each group was evaluated with histologi-cal and histomorphometric analyses. Results : According to histological observation, experimental group was showed more anastomosing newly-formed woven bone having osteoblastic activation than control group. According to histomorphometric analysis, there were 9.11% more newly-formed bone volume in experimental group than control group at 2 weeks, 7.91% more at 4 weeks, 20.08% more at 8 weeks. Conclusion: Our results demonstrated PRP in autogenous bone graft could enhance the bone formation.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제29권6호
• /
• pp.474-484
• /
• 2007

Purpose: The effect of platelet-rich plasma(PRP) on osteogenesis of marrow-derived osteoblasts on histomorphometric analysis in the mandible of rabbit was assessed. Materials and Method: Bone marrow cells were obtained from iliac bone of rabbits and were cultured in a Dulbecco's Modified Eagle's Medium(DMEM) with Dexamethasone, L-Ascortic acid, ${\beta}$-Glycerophosphate to proliferate and differentiate into osteoblasts for $4{\sim}5$ weeks. The expression of osteogenic mar-kers was detected by reverse transcription-polymerase chain reaction(RT-PCR) and silver nitrate stain. Then we prepared bony defects in the mandible of rabbit, 10.0mm in diameter and 4.0mm deep, by trephine bur. In the control group, the defects were filled with autogenous bone and cultured osteoblasts. In the experimental group, the defects were filled with autogenous bone, cultured osteoblasts and PRP. 2 weeks, 4 weeks, 8 weeks later, each group was evaluated with histological and histomorphometric analyses. Results: In vitro, osteoblasts were identified on RT-PCR and silver nitrate stain. According to histological observation, at 2 weeks well-developed anasto-mosing newly-formed woven bone was observed, at 4 weeks anastomosing newly-formed woven bone having osteoblastic activation was observed, and at 8 weeks thick newly-formed woven bone was observed in both control and experimental groups. According to histomorphometric analysis, there were 1.5% more newly-formed bone volume in experimental group than control group at 2 weeks, 28.4% more at 4 weeks, 4.3% more at 8 weeks. Particularly there were significant differences in bone volume at 4 weeks and 8 weeks new bone. Conclusion: Our results demonstrated PRP may enhance osteogenesis of marrow-derived osteoblasts at 4 weeks, 8 weeks.

• 약학회지
• /
• 제55권5호
• /
• pp.374-378
• /
• 2011

This study was performed to evaluate enhanced effect of fermented Galgeun tang (GGT) and Ssanghwa tang (SHT) on the anti-platelet aggregation. Platelet aggregation assay was performed In vitro using human platelet rich plasma(PRP) and In vivo using SD-rat plasma by platelet aggregometer. Pharmacodynamic parameters, $E_{max}$ and $EC_{50}$, were calculated using Winnolin. SD-rats administered 1 g/kg of oriental medicine every 12 hr for 8 days. Platelet aggregation was measured by optical method with collagen inducer (4 ${\mu}g$/ml). In In vitro anti-platelet study, $EC_{50}$ of GGT-A was lower than that of GGT-con about 79.13 ${\mu}g$/ml. And $EC_{50}$ of SHT-A and SHT-B was lower than that of SHT-con about 122.73 and 110.15 ${\mu}g$/ml, respectively. It is assumed that fermented GGT and SHT were more effective than original medicine. In multiple administration study, anti-platelet effect was significantly increased both GGT and SHT. Fermented GGT and SHT were more effective than original herbal medicine on anti-platelet aggregation.

• 생약학회지
• /
• 제33권2호통권129호
• /
• pp.120-123
• /
• 2002

The possibility of Galla Rhois(GR) water extract as an antithrombotic agent was investigated. The effect of GR on platelet aggregation in human platelet-rich plasma(PRP) induced by collagen and ADP in vitro and coagulation parameters in a pathological model induced by endotoxin and hydrocortisone acetate(HA) in vivo were examined. In platelet aggregation assay, GR extract significantly inhibited platelet aggregation induced by collagen and ADP in a dose-dependent manner. GR extract significantly increased the number of platelet and shortened prothrombin time(PT) and activated thromboplastin time(APTT) as compared with the control in pathological model induced by endotoxin and HA. Also, GR extract significantly increased fibrinogen level as compared with the control in a pathological model induced HA. These results suggest that GR may be a promising antithrombotic agent.

• 대한약리학회지
• /
• 제20권1호
• /
• pp.41-46
• /
• 1984

카드뮴중독으로 혈소판응집이 항진되어 고혈압 또는 동맥경화증이 발생한다는 연구보고를 감안하여 가토와 흰쥐의 생체내 실험으로서 미세혈전의 형성, Malondialdehyde(MDA) 및 thromboxane $B_2(TXB_2)$치에 미치는 카드뮴의 효과를 검토하고, in vitro실험으로 카드뮴을 처치한 가토 대동맥절편이 혈소판응집에 미치는 영향을 관찰하였으며, prostacyclin의 합성능력을 측정하여 그 결과를 다음과 같이 요약하였다. 1)Cadmium chloride 2mg/kg을 매주 동물의 복강내에 주입하였을 때 미세혈전형성이 증가되었다. 2) 카드뮴 중독동물의 platelet-rich plasma (PRP)는 MDA와 $TXB_2$형성이 정상동물에서 보다 현저히 증가되었다. 3) 카드뮴을 중독시킨 가토의 platelet-poor plasma (PPP)에서의 lipid peroxide치는 대조군과 차이가 없었다. 4) In vitro 실험으로, 가토대동맥 절편에서의 6-keto-$PGF_{1{\alpha}}$의 생성은 카드뮴 농도에 비례하여 억제되었고 이때 혈소판 응집률의 증가와 평행하였다. 5) 이상의 결과로서 카드뮴은 동맥내피세포에서 prostacyclin 합성을 억제할 뿐만 아니라 혈소판에서 $TXA_2$합성을 촉진시켜 그 결과로 혈소판 응집률을 증가시켰음을 알 수 있었다.

• Journal of Periodontal and Implant Science
• /
• 제48권4호
• /
• pp.224-235
• /
• 2018

Purpose: The purpose of this study was to evaluate the effects of platelet-rich plasma (PRP) on periodontal healing of replanted root surfaces in dogs histologically and histomorphometrically. Methods: A total of 36 roots of mandibular incisors and premolars from 6 mongrel dogs were used. The roots were randomly divided into 3 groups: 1) a positive control group (n=12), in which the periodontal ligament (PDL) and cementum were retained and the roots were soaked in saline; 2) a negative control group (n=12), in which the PDL and cementum were removed and the roots were soaked in saline; and 3) an experimental group (n=12), in which the PDL and cementum were removed and the roots were soaked in PRP. After soaking the root surfaces, the extracted roots were replanted into the extraction sockets. The roots were covered using a coronally repositioned flap Results: Histologically, irregular-thickness PDL-like and cementum-like tissues were observed in the 4-week experimental group and the positive control group. PDL-like tissue and cementum-like tissue with a more uniform thickness were observed at 8 weeks. In the negative control group, PDL-like tissue and cementum-like tissue were rarely found, and root resorption and ankylosis were observed. In the cross-sectional histomorphometric analysis, the experimental group demonstrated a higher rate of formation of cementum-like tissue and a lower tooth ankylosis rate than the positive and negative control groups at 4 and 8 weeks. Although there was a significant difference in the tooth ankylosis rate and the formation of cementum-like tissue across the 3 groups (P<0.05), no statistical significance was observed between any pair of groups (P>0.017). Conclusions: Applying PRP to root surfaces during tooth replantation in dogs can reduce tooth ankylosis and increase PDL-like and cementum-like tissue formation.

• 약학회지
• /
• 제56권6호
• /
• pp.382-389
• /
• 2012

Effects of citrate-capped silver nanoparticles (AgNPs) on the blood coagulation and platelet aggregation were investigated using whole blood, platelet rich plasma (PRP) and washed platelet obtained from SD male rats. To confirm the stability of AgNPs in the test, size distribution of the nanoparticles was measured in the vehicles including distilled water, serum, and platelet buffers. The average size of AgNPs was 20 nm in the vehicles, which means that the stability was maintained during the whole experimental period. When blood coagulation was monitored by using whole blood impedance aggregometer, coagulation was not observed at the concentration of 1, 10 and 50 ppm. Platelets in plasma or in buffer were not aggregated by AgNPs at the concentration of 1, 2 and 4 ppm, respectively. The test concentration of AgNPs could not be increased because the dark color of the nanoparticles impeded the transmission of light, which is an indicator of aggregation. Although the blood or platelets were pre-activated by collagen, thrombin, or ADP with sub-threshold level, aggregation was not observed at the test concentration. Microscopic observation also supported the result obtained by the aggregometer.

• Journal of Nutrition and Health
• /
• 제32권5호
• /
• pp.561-569
• /
• 1999

In the atherosclerotic subjects, arterial endothelial cell injury and plaque formation are suspected to be strong causable factors in developing acute coronary syndrome, and it was revealed that platelets have a very important role in this case. Women are exposed to atherosclerosis at a different degree after menopause or oral contraception. The purpose of this study was to determine the effects of endogenous and exogenous estrogen on the degree of platelet aggregation in platelet rich plasma(PRP) in twenty nonsmoking healthy Korean women for 12 weeks. The subjects were assigned to three groups: (1) eight women aged 49 to 60(yr) for the postmenopausel(Pst) group, (2) eight, aged 22 to 30(yr) for the premenopausa(Pre) group, (3) four, aged 23 to 30(yr) for the oral contraceptive (OC) group which used triphasic OC formulation. Fasting blood sample were obtained from the subjects, (1) once per 6 weeks in the Pst group, (2) every phase of the menstrual cycle in the Pre group, (3) each once during and after OC administration in the OC group. ADP, collagen and epinephrine were used as aggregating reagents, and platelet aggregation and time(Δt: time reaching to the maximum point of aggregation) in PRP were measured at the maximum point of aggregation in five minutes. All the data were adjusted for dietary effects, personality type and body mass index(BMI) by using analysis of covariation(ANCOVA). Platelet aggregation to ADP and collagen(MADP and MCOLL) were not significantly different among the three groups, and Δt to ADP and collagen(TADP and TCOLL) were not either. But maximum platelet aggregability and Δt to epinephrine(MEPIN and TEPIN) were significantly different among the three groups, and the OC group showed the lowest value (p<0.01). Maxtimum platelet aggregability and Δt during the menstrual cycle were not significantly different in the Pre group. Any other significant differences in the maximum platelet aggregability and Δt were found between oral contraception phase and washing out phase(menstruation) in the OC group. In results, maximum platelet aggregability and aggregation time to ADP and collagen seemed not to be affected by endogenous and exogenous estrogen, even though MEPIN and TEPIN showed significantly low in the OC group among the three groups.