• Proceedings of the Korean Vacuum Society Conference
• /
• 2011.02a
• /
• pp.259-260
• /
• 2011

대기압 플라즈마는 멸균과 살균, 지혈, 피부재생, 치아 미백 등 여러 의학 분야를 대상으로 그 효과를 나타내고 있으며, 플라즈마 장비를 만들어 내기 위해 부피가 큰 진공 장비가 필요하지 않다는 점에서 대기압 플라즈마는 그 활용과 효과에 있어 큰 기대를 받고 있다. 대기압에서 플라즈마는 다양한 주파수를 이용하여 만들어져 왔으며, 본 연구실에서 연구하고 있는 수백 MHz-수 GHz 대역의 파워를 사용하는 플라즈마의 경우 대기압 플라즈마를 의학 분야에 사용할 때 만족해야 할 조건들에 만족하는 특성을 보여준다. 기존의 고주파를 사용하는 장비의 경우 추가적인 Matching 장비로 인해 플라즈마를 만들기 위해 큰 장비와 높은 파워가 필요한 단점이 있었다. 하지만 이 마이크로웨이브 장비는 전송선 이론을 기반으로 장비 자체가 구조적인 Matching이 이루어 지도록 설계되었다(그림 1). 즉, 추가적인 Matching 장비의 필요 없이 외부에서 파워를 주는 것만으로 플라즈마를 발생 시킬 수 있으며, 50% 이상의 파워 효율을 보여준다. 또한 그 크기도 손에 쥐고 사용할 수 있을 볼펜 정도의 크기이며, 3W의 정도의 저 전력으로 플라즈마를 발생 시켰다. 높은 에너지를 가지는 전자들은 공급되는 기체뿐만 아니라, 주변 공기와의 반응하여 여러 응용분야에 적합한 활성 종을 다량 만들어내게 된다. 본 연구실의 강점인 플라즈마 시뮬레이션으로 얻은 결과에서 주파수가 올라 갈수록 높은 에너지를 가지는 전자들이 많아지는 것을 보여준다. 그리고 발생시킨 플라즈마의 광학 특성에서도 생의학 분야에 적합한 많은 활성 종들이 발생 되는 것을 확인하였다. 일반적으로 의학 분야에 사용되는 플라즈마의 경우 플라즈마에서 발생하는 열에 의한 피해를 최소화 하는 것이 중요하다. 마이크로웨이브 플라즈마의 경우, 그 플라즈마의 온도가 50$50^{\circ}$C 미만으로 의학 분야에 사용하기 적합하다. 또한 구동 주파수가 올라갈수록 플라즈마를 유지하는데 필요한 전압이 상대적으로 낮아지게 되는데, 이는 전기적 쇼크 등 플라즈마 의용에서 발생하는 안전성 문제에 있어서도 마이크로 웨이브 장비가 좋은 점이다. 본 플라즈마 장비를 구동하기 위한 손바닥 크기 정도의 소형의 전용 파워 장치를 개발함으로써 저전력 소형 플라즈마 장치를 개발하는 것을 목표로 하고 있다. 마이크로 웨이브 장비는 여러 가지 분야에서 그 효과를 검증 받았다. 혈액 응고 실험에서 30초 정도의 짧은 처리만으로도 자연 응고에 비해 탁월한 지혈 효과를 보여줬다 (그림 2). 충치를 발생시키는 대표적인 구강균인 S.mutans의 살균 실험에서 Ti02와의 복합적인 처리를 통해 30초 미만의 처리로 처리하지 않은 것에 비해 10-6 만큼의 줄어드는 살균 효과를 보여줬다. 뿐만 아니라 치아의 미백에 있어서도 탁월한 효과를 나타냈다. 현재 본연구실에서는 마이크로 웨이브 장비의 기본적인 구조를 응용하여, 좀더 넓은 영역을 처리할 수 있는 대면적 마이크로 웨이브 장비를 위한 연구를 수행 중이다.

• The Journal of Korea Assosiation for Disability and Oral Health
• /
• v.15 no.1
• /
• pp.45-49
• /
• 2019

Bartter syndrome is an inherited renal tubular disorder characterized by hypokalemia, hypochloremic metabolic alkalosis, hyperreninemia, hyperprostaglandinism, and normal blood pressure. Bartter syndrome is classified by neonatal and classic type. Clinical manifestation of Bartter syndrome considered in dental treatment include tendency to dehydration, vomiting and erosion, attrition and abrasion of the teeth. A 2-year-4 month old boy with Bartter syndrome type III was referred to the Seoul National University Dental Hospital for dental evaluation and treatment. He showed hypokalemic hypochloremic metabolic alkalosis and had been treated with indomethacin and potassium chloride. He had hypocalcified teeth with or without multisurface caries lesions in all dentition and the erosion of maxillary teeth was detected. Dental procedure under general anesthesia was scheduled due to multiple caries and his medical condition. The dental procedure was successfully performed. This case suggests that electrolyte imbalances need to be treated prior to dental treatment and complete coverage restoration is necessary to protect the eroded teeth. An appropriate management plan for the patients with Bartter syndrome should include considerations of the need for close interaction with the pediatrician for pre- and post-operative care. General anesthesia may be recommendable to manage the patients having multiple caries with Bartter syndrome.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.49 no.4
• /
• pp.357-367
• /
• 2022

Sleep disordered breathing (SDB) is a disease characterized by repeated hypopnea and apnea during sleep due to complete or partial obstruction of upper airway. The prevalence of pediatric SDB is approximately 12 - 15%, and the most common age group is preschool children aged 3 - 5 years. Children show more varied presentations, from snoring and frequent arousals to enuresis and hyperactivity. The main cause of pediatric SDB is obstruction of the upper airway related to enlarged tonsils and adenoids. If SDB is left untreated, it can cause complications such as learning difficulties, cognitive impairment, behavioral problems, cardiovascular disease, metabolic syndrome, and poor growth. Pediatric dentists are in a special position to identify children at risk for SDB. Pediatric dentists recognize clinical features related to SDB, and they should screen for SDB by using the pediatric sleep questionnaire (PSQ), lateral cephalometry radiograph, and portable sleep monitoring test and refer to sleep specialists. As a therapeutic approach, maxillary arch expansion treatment, mandible advancement device, and lingual frenectomy can be performed. Pediatric dentists should recognize that prolonged mouth breathing, lower tongue posture, and ankyloglossia can cause abnormal facial skeletal growth patterns and sleep problems. Pediatric dentists should be able to prevent these problems through early intervention.

• Journal of Oral Medicine and Pain
• /
• v.18 no.2
• /
• pp.97-106
• /
• 1993

This study was performed to investigate the effects of infrared and visible light laser irradiation on cell viability of human gingival fibroblast. For the present study, the author used cultured fibroblast originated from sound gingiva which were fifth of sixth passage. Laser machine utilized here were stomalaser which irradiate infrared (GaAs diode) and red (HeNe) laser in turn with pulse wave pattern or continuous wave pattern, and the machine had several frequency mode presented by regeneration, relaxation and analgesic modalities. Cultured fibroblast samples were divided by this modalities of cell counts and laser exposure time which were 7-seconds of 150 seconds, respectively. 1 day after laser irradiation, each cell-well was treated with MTT and measured optical density with ELISA. The obtained results were as follows : 1. There was a tendency of increasing optical density in proportion to irradiation time in groups of $1\times10^4$ cell per well but in groups of $5\times10^3$ cell per well, reverse phenomena were observed. 2. The difference of optical density according to frequency modalities were not showed significantly except several cases in groups of $5\times10^3$ cell per well. 3. In general, cell viability of cultured human gingival fibroblast wer not showed consistent feature by low level laser irradiation.

• Journal of Oral Medicine and Pain
• /
• v.21 no.1
• /
• pp.153-171
• /
• 1996

저수준레이저를 이용하여 창상이나 병소의 치유과정에 대한 효과를 조사하기 위하여 많은 연구가 시행되었다. 연구에 의하면 갈륨비소 레이저광이 생체자극효과를 가진다고 하며, 저수준레이저를 조사하면 단백질과 핵산 (DNA) 합성을 자극하여 치은섬유아세포의 증식을 촉진한다고 보고하였다. 외상병소나 근육병소의 치료에 사용된 레이저치료법에 관한 관심이 점증함에 따라 저수준레이저요법 (LLLI)의 치유효과를 설명하기 위하여 분자생물학적 수준의 연구를 시행하기에 이르렀다. 보고에 의하면 Mutans Streptococcide 는 LLLI를 사용시 증식이 촉진되며, 다른 세균에서도 유사한 증식효과가 나타날 것이라고 주장하였다. 그러므로 LLLI가 피부감염을 야기하는 가장 흔한 원인인 Staphylococcus aureus 도 마찬가지로 증식이 촉진되는 지를 조사해볼 필요가 있으며, 또한 감염과 같이 특정 병적 상태에서의 저수준레이저광의 효과는 아직까지 명확하게 밝혀져 있지 않았다. 그러므로 본 연구의 목적은 첫째, Staphyloc occus aureus 의 증식에 대한 저수준레이저광의 효과를 조사하는 실험이며, 둘째 Staphylococcus aureus 로 가염된 피부창상에 대한 저수준레이저광의 효과를 판정하는데 있다. 34개의 Staphylococcus aureus 배양표본을 사용하여 48시간의 세포주기동안 조사기간과 조사시간, 그리고 레이저 펄스(laser pulse)형에 따라 3가지 실험을 시행하여 증식에 가장 효과적인 상태와 가장 비효과적인 상태의 갈륨비소 반도체 레이저펄스를 결정하였다. 이후 지름 약 6 mm의 개방창상을 44마리 백서의 양측 대퇴부에 형성하여 모든 창상에 S. aureus를 감염시켰다. 모든 표본은 펄스형과 조사방법 (중앙조사법과 주변조사법)에 따르는 실험을 하기 위하여 4가지로 분류하였다. 각 백서의 양측 창상중 하나는 1,3,5,7일 마다 각 실험의 방법에 따라 레이저를 조사하고 실험동물의 다른 창상은 대조군으로서 사용하였다. 모든 창상의 면적은 실험 1,3,5,7 일째에 일정한 거리에서 사진촬영하여 면적계를 이용, 측정한 후 통계적인 의의를 조사하였다. 본 연구의 결과는 저수준레이저는 특정 조건하에서 S. aureus의 증식을 촉진하였다. 그러나 S. aureus에 감염된 창상을 저수준레이저로 조사시 치유가 촉진되었다. 중앙 조사법고 주변조사법에 의한 창상치유효과는 통계적인 의의가 보이지 않았다. 따라서 결론적으로 S. aureus 에 감염된 창상에 직접 또는 간접적이든 pulse의 종류에 관계없이 조사하는 경우 치유효과가 나타나는 것은 정사주위 조직의 LLLI 자극효과가 염증의 확산을 억제한다고 말할수 있다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.28 no.1
• /
• pp.24-30
• /
• 2002

The facial patterns were expressed by the interrelation of variable factors such as heredity, function and environment. Such variable factors have an effect on the growth and development of maxillofacial bones. The malocclusions with skeletal discrepancies are caused by abnormal forms, sizes and positions of cranial base, maxilla and mandible. For the proper diagnosis and treatment planning, the analysis of such structures is necessary. Lateral cephalograms of 54 adults with class III malocclusion patients (test group) and 61 adults with normal occlusion (control group) were analyzed. Anteroposterior relations and sizes of cranial base, maxilla, mandible were estimated to compare with those of normal ones. In test group, the anterior cranial base length was within normal range, but posterior cranial base, maxilla and mandibular body were longer than those in control group, significantly. Based on the cranial base, the location of maxilla in test group was normal, but the location of mandible was more anterior than that in control. Based on the maxilla, the location of mandible was more anterior in test group than that in control. Both mandibular body and ramus anteroposterior lengths in test group were larger than those in control. Both mandibular plane angle and upper gonial angle were within normal range, but lower gonial angle was significantly high in test group.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.35 no.5
• /
• pp.346-352
• /
• 2009

There have been reports of successful bone formation with sinus floor elevation by simply elevating the maxillary sinus membrane and filling the sinus cavity below the lifted sinus membrane with a blood clot. But, in a review of the current literature, we found no animal study that substantiated blood clot's ability in this respect. The aim of this study was to investigate the effect of the method of maxillary sinus floor augmentation using the patient's own venous blood in conjunction with a sinus membrane elevation procedure. An implant was placed bilaterally in the maxillary sinus of six adult mongrel dogs so that it protruded 8 mm into the maxillary sinus after sinus membrane elevation. On one side of the maxillary sinus, the resultant space between the membrane and the sinus floor was filled with autologous venous blood retrieved from the dog. On the opposite side, the maxillary sinus was left untreated as a control. The implants were left in place for six months. The mean height of the newly formed bone in the sinus was 3.7 mm on the side without venous blood and 3.5 mm on the side with venous blood (p>0.05). There was no difference between the two sides regarding new bone height in the sinus. Our results indicate that filling the space between the lifted sinus membrane and the sinus floor with venous blood has no effect on bone formation around implants placed in the maxillary sinus cavity.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.32 no.1
• /
• pp.152-157
• /
• 2005

Hypophosphatemia rickets, also known as Vitamin D-resistant rickets(VDRR) and refractory rickets, is a form of rickets which is resistant to the usual doses of vitamin D. VDRR is characterized by decreased renal tubular reabsorption of inorganic phosphate and is easily diagnosed by a normal blood calcium, hypophosphatemia, and slightly elevated alkaline phosphatase. Clinical features of Hypophosphatemia rickets included lateral bowing deformities of the legs, short stature, scoliosis, and enlargement of wrist and ankles. Dental finding in patient with VDRR were spontaneous dental abscesses in caries free teeth and other dental findings included delayed eruption, delayed apical closure, thin and hypoplastic enamel, absent or poorly defined lamina dura, enlarged pulp chambers, and numerous accessory canals and pulp horns that extend up and into the dentinoenamel junction. we reported the clinical feature and treatment of VDRR child who was referred from the department of pediatrics for early loss of primary teeth and its treatment.

• Journal of Oral Medicine and Pain
• /
• v.20 no.1
• /
• pp.53-65
• /
• 1995

The growth and synthetic activities of fibroblasts are regulated by cytokines and growth factors derived from activated inflammatory cells. Stimulatory effect of low level laser (LLL) radiation on wound healing seems to be in part due to direct stimulatory action on cell proliferation and synthetic activities of fibroblasts. Also indirect stimulatory effect on the fibroblast function through inflammatory or immune cells is another possible mechanism of biostimulatory action of LLL. This study was performed to determine the growth rate of human gingival fibroblasts obtained biopsy and culture, fibroblast cell line, and immune cell line by using $[^3H]-$ thymidine incorporation test. And gene expression pattern was also analyzed by using the DNA probe such as Hsp70, IL-1$\beta$, MIP-1$\alpha$ and actin cDNA. Proliferation rate of gingival fibroblast was increased by LLL irradiation, but no more effect was added by LPS or IL-1$\beta$ pretreatment Enhanced Hsp70 gene expression was found from gingival fibroblasts and fibroblast cell line COS by LLL irradiation., which was not more increased by LPS or IL-1$\beta$ pretreatment. LLL-irradiated promyelcytic cell line HL-60 and macrophage cell line RAW264.7 showed significant stimulatory effect of proliferation rate when compared with respective control. However there were no changes in growth rate of other immune cell tested in this study, such as B cell line WR19n.l and 230, helper T cell line Jurkat and Hut78, cytolytic T cell line CTLL-r8. By LLL-irradiation Hsp70 gene expression was increased in RAW246.7 and HL-60, not in CTLL-R8. And IL-1$\beta$ and MIP-1$\alpha$ gene expression were induced only from LLL-irradiated RAW264.7. These results led us to presume that LLL radiation may affect to the immune cells, especially to macrophage, through which it might promote wound healing process.

• Journal of The Korean Dental Society of Anesthesiology
• /
• v.12 no.2
• /
• pp.99-104
• /
• 2012

Anticoagulation therapy with warfarin sodium is used to reduce the risk of thromboembolic events in patients with valvular heart disease, prosthetic heart valve, recurrent myocardiac infarction, etc. To keep anticoagulation state and minimize bleeding risk, patients with high risk of thromboembolism have been usually hospitalized for heparinization before oral surgery like extraction. However, this protocol requires time and high expense because of the long period of hospitalization and this is why low-molecular-weight heparin (LMWH) therapy is receiving attention in medical field as well as dentistry. LMWH has several advantages over unfractionated heparin (UFH) including predictable anticoagulant response which makes coagulation monitoring unnecessary in most patients and longer half-life than heparin which enables the patients to give themselves a subcutaneous injection once or twice daily. These advantages of LMWH make patients get oral surgery on an outpatient basis so that they can save time and cost. This case report introduces the use of LMWH in dental surgery and suggests proper use of LMWH. Though LMWH bridging therapy is widely used most of the previous studies are observational studies. Therefore randomized controlled trials are necessary to evaluate the safety and efficacy of LMWH bridging therapy.