Factors influencing unmet needs for health care by income groups

학위논문(석사) --서울대학교 보건대학원 :보건학과(보건정책관리전공),2010.2.Maste

일체형 지대주의 Diamond Like Carbon 표면 처리와 나사 조임 시기가 풀림 현상에 미치는 영향

본 연구의 목적은 내측연결형 임플랜트와 일체형 지대주를 사용하여 최종 보철물을 시적한 뒤에 5만 번의 반복하중 후에 다시 체결하고 20만 번의 반복하중을 가한 후의 지대주 풀림토크와 20만 번의 반복하중을 받은 지대주 풀림토크가 어떻게 달라지는지를 비교하고자 하는 것이다. 실험 재료로는 타이타늄 지대주와 DLC 코팅된 지대주를 사용하였다. 실험군은 4군으로 모두 8개의 ITI SLA 를 사용하였다. A군과 B군은 5만번, 20만번 반복하중을 가하고 Periotest값과 풀림 토크값을 측정하였으며 C군과 D군은 20만번 반복하중을 가하고 Periotest 값과 풀림토크값을 측정하였다. 풀림 토크값의 측정은 디지털 토크 게이지를 사용하였고, 반복하중은 MTS. (Bionix 850 II, MTS, U.S.A.)를 사용하였으며 100N/cm의 힘을 20도의 경사, 14Hz 의 조건으로 가하였다. A군과 C군은 코팅하지 않은 타이타늄 지대주를 사용하였으며, B군과 D군은 DLC 코팅한 지대주를 사용하였다. 1. 5만번 반복하중을 가한 뒤 측정한 풀림 토크는 B군에서 약간 더 큰 평균값을 보였다. 하지만 통계학적으로 두 군간에 유의한 차이를 보이지 않았다 (P>0.05). 2. 20만번 반복하중을 가한 뒤 측정한 최종 풀림 토크 값은 A군은 C군보다, B군은 D군보다 약간 더 큰 평균값을 보였으나 통계학적으로 두 군간에 유의한 차이를 보이지 않았다 (P>0.05). 3. 20만번 반복하중을 가한 최종 풀림 토크 값은 A, B군과 C, D군 사이에 통계학적으로 유의할 만한 차이가 없었다 (P>0.05). Statement of problem: It is difficult about assessing the loosening tendency of conical connection type implant after cyclic loading with diamond like carbon coating one-piece abutments, and also about the retightening effect. Purpose: This study was performed to investigate the influence of one-piece abutment screw retightening after cyclic loading and Diamond like coating Material and methods: Thirty two ITI implant were divided to 4 groups. Group 1,3-titanium abutment, group 2,4 - diamond like carbon coated abutment. Group 1,2 - cyclic loading after cyclic loading, Group 3,4- after Cyclic loading. After cyclic loading, periotest values were taken and removal torque values of abutments were measured with a digital torque gauge. Results: 1. The removal torque of group 2 after cyclic loading is slightly greater than the other groups but not significantly higher than others (P>0.05). 2. The final removal torque values after cyclic loading of group 1 is bigger than group 3, and group 2 is bigger than group 4, but not significantly higher (P>0.05). 3. The final removal torque values after cyclic loading of all groups are not significantly different (P>0.05)

A STUDY ON THE MANDIBULAR MOVEMENTS OF TMD PATIENTS

The purpose of this study was to evaluate the mandibular movements of TMD patients comparing to normal persons. Sirognathograph was used to measure five parameters of mandibular movements of twenty normal persons and eight TMD patients. Five parameters were (1) Maximum opening during maximum opening and closing, (2) Mean velocity during maximum opening and closing, (3) Maximum opening during unilateral chewing, (4) Mean velocity during unilateral chewing, (5) Consistency of mandibular movement during unilateral chewing. Based on above results, new Mandibular Movement Index(M.M.I.) was formulated and compared to Helkimo's Clinical Dysfunction Index by measuring two indices before treatment and 2 weeks, 4 weeks, 6 weeks, 8 weeks after treatment. The conclusions were as follows: 1, The amounts of maximum opening and mean velocity during maximum opening and closing of TMD patients were less than those of normal persons(p<0.01). 2. The amounts of maximum opening and mean velocity during unilateral chewing of TMD patients were less than those of normal persons(p<0.05) (P<0.01). 3. Although TMD patients showed limited mandibular movements during unilateral chewing, the consistency of mandibular movements was better than that of normal persons(p<0.05). 4. Both mandibular movement index and Helkimo's Clinical Dysfunction Index, were useful in diagnosing TMD patients

파절된 임프란트 고정체의 분석과 처치

Among the numerous factors contributing to implant failure, the most common are infection, failure of proper healing and overload. These factors may occur combined. Implant fractures are one of the complications resulting from overload. Implant fracture is not a common feature, but once it occurs it causes very unpleasant circumstances for the patient as well as for the practitioner. Only few studies have been reported regarding this subject. Thus, little is known about its solutions. It is important that analyzing reasons for implant fracture and finding appropriate solutions. Factors leading to implant fracture are design, material defects, nonpassive fit of prosthetic framework and biomechanical overload. Previous studies have reported that implant fractures ares associated with marginal bone loss and occur mostly in the posterior regions and that most patients showing parafunctional habits also have implant fracture. Abutment and gold screw loosening or fracture were also observed in some of the cases previous to implant fracture. Similar observations were seen in our hospital as well. The following cases will present implant fracture cases which have been successfully treated regarding function and biomechanics. This was achieved by means of using increased number of futures, increasing fixture diameter and establishing proper occlusion.본 논문은 보건복지부 선도기술 의료공학 기술개발사업의 지원에 의하여 이루어졌습니다

Strains of abutment and bones on implant overdentures

Statements of the problem: Over the past decades, conventional complete dentures were used for various patients although they have incomplete function. Overdentures using dental implants could help the improvement of denture function. Purpose: The purpose of this study was to compare the strains of abutment and bone on implant overdenture between splinted and unsplinted type of prosthesis. Additionally, the strain values of parallel placed implant model and unparallel placed implant model were compared. Material and methods: Two acrylic resin model were prepared and two implants were placed at the canine positions in each model. In the first model, two implant were placed parallel. In the second model, two implants were placed with 10 degree labiolingual divergence. Two types of abutment were connected to the fixtures alternatively. One was splint type of Hader bar, the other was unsplint type of ball abutment. Overdentures were fabricated with corresponding attachment systems and seated on abutments. Strains of abutments and labial bone simulants were measured with electric resistance strain gauges when static load from 100 N to 200 N were applied to overdentures. Results: 1. Splinted type of overdentures using bar and clip showed higher absolute strain values. But the strain was compressive and the load was shared by two implants(P<.05). 2. Unsplinted type overdentures using ball and O-ring showed low absolute strain values(P<.05). 3. Labially inclined implant showed higher tensile strain values in unsplinted type of prosthesis than in splinted type of prosthesis. Lingually inclined implant showed rather low strain values under load(P<.05). 4. Non parallel implant model showed higher absolute strain values than parallel placed implant model comprehensively(P<.05)

의치상 레진의 세포독성에 관한 연구

The purpose of this study was to investigate the cytotoxicity and mutagenicity of denture base resins. According to manufacturer's instructions, resin specimens were made. Group 1 : heat-polymerizing acrylic resin (Luciton ) Group 2 : heat-polymerizing acrylic resin containing polyhedraloligosilsesquioxane(POSS resin) Group 3 : auto-polymerizing acrylic resin (Repair ) Group 4 : direct relining auto-polymerizing acrylic resin (Tokuso ). Fresh specimens 24 hrs. and 72 hrs. soaked specimens in distil)ed water were made. Responses with metabolic assay and mutagenesis assay to eluates from resin specimens were measured. Cultures with medium alone provided controls. Cytotoxicity was assessed with agar overlay test. The results were as follows; 1. Group 4 showed higher cytotoxicity than Group 1, Group 2 and Group 3 in fresh, 24-an4 72-hour immersion caries (p<.05). Group 3 showed higher cytotoxicity than Group 2 in fresh cases and showed higher cytotoxicity than Group 1 and Group 2 in 24-and 72-hour immersion cases (p<.05) . Group 1 and Group 2 showed no significant difference. 2. All acrylic denture base resins skewed significant increase of cell activity as immersion time increased (p<.05). 3. Auto-polymerizing acrylic denture base resins skewed higher cytotoxicity than heat-polymerizing acrylic denture base resins (p<.05). 4. All acrylic denture base resins showed lower mutagenicity than controls (p<.05)