• 제목/요약/키워드: Dental inlay

검색결과 63건 처리시간 0.017초

CERAMIC INLAY RESTORATIONS OF POSTERIOR TEETH

  • Jin, Myung-Uk;Park, Jeong-Won;Kim, Sung-Kyo
    • 대한치과보존학회:학술대회논문집
    • /
    • 대한치과보존학회 2001년도 춘계학술대회
    • /
    • pp.235-237
    • /
    • 2001
  • ;Dentistry has benefited from tremendous advances in technology with the introduction of new techniques and materials, and patients are aware that esthetic approaches in dentistry can change one's appearance. Increasingly. tooth-colored restorative materials have been used for restoration of posterior teeth. Tooth-colored restoration for posterior teeth can be divided into three categories: 1) the direct techniques that can be made in a single appointment and are an intraoral procedure utilizing composites: 2) the semidirect techniques that require both an intraoral and an extraoral procedure and are luted chairside utilizing composites: and 3) the indirect techniques that require several appointments and the expertise of a dental technician working with either composites or ceramics. But, resin restoration has inherent drawbacks of microleakage. polymerization shrinkage, thermal cycling problems. and wear in stress-bearing areas. On the other hand, Ceramic restorations have many advantages over resin restorations. Ceramic inlays are reported to have less leakage than resin restoration and to fit better. although marginal fidelity depends on technique and is laboratory dependent. Adhesion of luting resin is more reliable and durable to etched ceramic material than to treated resin composite. In view of color matching, periodontal health. resistance to abrasion, ceramic restoration is superior to resin restorationl. Materials which have been used for the fabrication of ceramic restorations are various. Conventional powder slurry ceramics are also available. Castable ceramics are produced by centrifugal casting of heat-treated glass ceramics. and machinable ceramics are feldspathic porcelains or cast glass ceramics which are milled using a CAD/CAM apparatus to produce inlays (for example, Cered. They may also be copy milled using the Celay apparatus. Pressable ceramics are produced from feldspathic porcelain which is supplied in ingot form and heated and moulded under pressure to produce a restoration. Infiltrated ceramics are another class of material which are available for use as ceramic inlays. An example is $In-Ceram^{\circledR}$(Vident. California, USA) which consists of a porous aluminum oxide or spinell core infiltrated with glass and subsequently veneered with feldspathic porcelain. In the 1980s. the development of compatible refractory materials made fabrication easier. and the development of adhesive resin cements greatly improved clinical success rates. This case report presents esthetic ceramic inlays for posterior teeth.teeth.

  • PDF

일부(一部) 대학생(大學生) 신체발육(身體發育) 및 건강상태(健康狀態)에 관(關)한 조사(調査) (A Study on the Physical Growth and Health Status in University Students)

  • 권이혁;차철환
    • Journal of Preventive Medicine and Public Health
    • /
    • 제1권1호
    • /
    • pp.67-78
    • /
    • 1968
  • For the purpose of ascertaining the status of physical growth and health status of the University students, a intensive survey was conducted by the authors towards a total of 2,638(male; 2,228, female; 410) who passed the written entrance examination at the Seoul National University. The items included the measurements on physical growth, various physical indixes, visual acuity, tuberculosis and dental status. The findings and results can be summarized as follows: 1. Physical Growth No significant difference was found in the physical growth between classes(literature and science) and by ages. In males, the means of body height, body weight, chest-girth and sittingheight were $168.0{\pm}5.07cm,\;55.7{\pm}5.71kg,\;85.8{\pm}4.4cm\;and\;91.5{\pm}2.21cm$, respectively. In females, these were $157.4{\pm}4.57\;cm,\;00.4{\pm}5.75kg,\;80.3{\pm}4.51cm\;and\;86.1{\pm}3.30cm$, respectively. Basing on the above measurements several physical indixes were calculated as follows ; Relative body weight 33.15 in males and 32.02 in females. Relative chest-girth 51.07 and 51.01, relative sitting-height 54.46 and 54.70 $R\ddot{o}hrer$ index 1.00 and 1.02, Kaup index 1.97 and 2.04, Vervaeck index 83.63 and 83.03, and Pelidisi index 89.94 and 92.45. 2. Visual Acuity Among the students of science classes those of 0.8 and below in vision on left and right occupied 46.4% and 45.0%, those of 0.6 and below 39.1% and 41.2%, respectively. Among the students of literature classes those of 0.8 and below occupied 46.3% and 42.9%, and those of 0.6 and below occupied 41.4% and 39.0, respectively. In males those of 0.8 and below occupied 46.8% and 44.5% and 0.6 and below occupied 41.9% and 39.7%, while in females 0.8 and below occupied 43.9%, and 42.4%, and 0.6 and below occupied 38.3% and 37.3%, respectively. In males those of 0.8 and below in corrected vision occupied 12.1% and 10.3%, while in females 12.9% and 12.2%, respectively. More students of abnormal vision were found among science classes and the proportions of corrected vision were 38.9% and 37.4% in males, and 33.9% and 33.2% in females, respectively. 3. Tuberculosis Among the total, 55 students were diagnosed as tuberculosis, of whom 50 were minimal cases, 2 were moderately advanced cases and 3 were far advanced cases. 4. Dental Status Among the total, 81.2% were of decayed teeth, 20.8% filled, 9.5% missed, 5.0% extraction needed, 9.1% sunplatinum bridges, 3.3% golden bridges and 5.5% golden inlay. Regarding tartar on teeth moderate, heavy and light grades occupied 49.5%, 29.7% and 20.3%, respectively and 0.8% had none. 5. Comprehensive evaluation According to criteria 4 grades were applied to comprehensive evaluation as follows : A...excellent in physical status B...with some physical defects but no difficulties in study C...need treatment D...need treatiment and rest Out of the total, A grade occupied 21.6%, B 76.2% and C. and D 2.2.

  • PDF

두경부 양성자 치료계획 시 MVCT를 이용한 Metal Volume 평가 및 양성자 선량분포 평가 (Evaluation of Metal Volume and Proton Dose Distribution Using MVCT for Head and Neck Proton Treatment Plan)

  • 서성국;권동열;박세준;박용철;최병기
    • 대한방사선치료학회지
    • /
    • 제31권1호
    • /
    • pp.25-32
    • /
    • 2019
  • 목 적: 두경부 방사선 치료 시 Dental Implant에 의한 Metal Artifact로 인해 보철물의 크기, 모양 및 Volume이 달라지고 이로 인해 타겟 및 주변 정상조직에 대한 방사선치료계획의 정확성이 떨어진다. 본 연구는 치아크기를 재현한 Metal을 KVCT, SMART-MAR CT, MVCT를 통해 영상을 획득 하여 Volume을 평가하고 양성자 치료계획에 적용시켜 선량분포의 차이를 분석해 보고자 한다. 대상 및 방법: 치과에서 치료하는 방법을 고려하여 인레이, 크라운, 브릿지와 비슷한 크기의 A보철물($0.5{\times}0.5{\times}0.5cm$), B보철물($1{\times}1{\times}1cm$), C보철물($1{\times}2{\times}1cm$)을 저용융점납합금(Cerrobend, $9.64g/cm^3$) 사용하여 제작하였다. In House Head & Neck Phantom 안에 보철물를 위치시키고 CT Simulator(Discovery CT 590RT, GE, USA)를 이용해 Slice thickness 1.25 mm로 KVCT 영상과 SMART-MAR 영상을 획득하였다. MVCT 영상은 $RADIXACT^{(R)}$ Series(Accuray $Pricision^{(R)}$, USA)을 이용해 동일한 방법으로 획득하였다. MVCT, SMART-MAR CT, KVCT를 통해 획득한 보철물의 형상을 전산화 치료계획장비 Pinnacle(Ver 9.10, Philips, Palo Alto, USA)의 Autocontour Thresholds Raw Values를 통해 X, Y, Z축의 크기 및 Volume을 비교하였다. 양성자 치료계획은 위의 실험에서 얻은 보철물B($1{\times}1{\times}1cm$)의 각 CT별 치아 Contour를 KVCT 상에 fusion하여 양성자 치료계획(Ray station 5.1, RaySearch, USA)을 세우고 선량의 차이를 비교 평가하였다. 결 과: 실측 사이즈 대비 A보철물(MVCT : 1.0배, SMART-MAR CT : 1.84배, KVCT : 1.92배), B보철물(MVCT : 1.02배, SMART-MAR CT : 1.47배, KVCT : 1.82배), C보철물(MVCT : 1.0배, SMART-MAR CT : 1.46배, KVCT : 1.66배)로 각 크기의 보철물에서 MVCT가 가장 실제 Volume과 유사하게 측정되었다. 양성자 치료계획에서 B보철물의 Volume을 각각 적용하여 측정한 결과 $D_{99\%}$ volume의 선량이 기준 3082 CcGE 대비 MVCT:3094 CcGE, SMART-MAR CT:2902 CcGE, KVCT:2880 CcGE로 측정되었다. 결 론: 전체적인 Volume과 X축 Z축의 크기는 MVCT에서 실제 크기와 가장 일치했고 superior-Inferior방향인 Y축은 CT에 따라 차이 없이 길이가 일정했다. 두경부 양성자 치료 시 보철물의 크기, 모양 및 Volume이 비슷한 MVCT에서 가장 실제 값과 비슷한 선량분포를 보였고 MVCT를 이용한 보철물의 contour를 KVCT에 fusion하여 양성자치료계획에 적용 시 매우 유용할 것으로 사료된다.