• 제목/요약/키워드: Soft-Hard

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외과적 악교절수술에 있어서 측모연조직예측의 재평가에 대한 연구 (REAPPRAISAL OF SOFT TISSUE PREDICTION IN ORTHOGNATHIC SURGERY FOR MANDIBULAR PROGNATHISM)

  • 정무혁;남일우
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제13권1호
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    • pp.37-43
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    • 1991

  • 두부방사선사진을 이용한 안모의 측모예측은 악교정수술에 있어서 가장 중요한 수술전 치료계획의 한부분으로 술후 경조직과 연조직의 변화를 예상하며 술자와 환자간에 술후 결과를 의논하는 대화의 재료로서도 그 중요성이 크다. 그러나, 술후 환자의 최종적인 측모와 수술 직전에 수술 계획에 따라 시행한 술후 측모의 예측과는 차이가 있다. 이러한 수술 전 시행하는 측모 예측의 부정확성을 감소시키기 위하여 새로운 경조직 대 연조직 변화비율 등을 추정하는 많은 연구가 시행되어 왔으나 측모방사선 예측의 부정확도를 조사하고 이러한 부정확성에 영향을 미치는 변수를 확인함이 측모방사선예측의 부정확성을 이해하고 감소시키는 데에 있어서 그 중요성이 크다고 생각된다. 이에 저자들은, 이미 시행되어 수술에 사용된 술후 측모예측기록을 수술직후 두부방사선 사진 및 술후 최소 6개월 추적 방사선 사진에 중첩하여 측모 예측의 부정확도를 조사한 바 총 30명의 환자에서 20명(66.6%)이 부정확도를 보였고 악골 및 치열의 술후 위치 불안정성도 측모 예측 정확군과 부정확군에 모두 19명(63.3%)에서 발생하여 측모 예측의 부정확도 영향을 주는 중요한 요인으로 확인되었다.

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DS-CDMA 셀룰라 시스쳄에서의 소프트 핸드오프율에 대한 분석 (Analysis of the soft handoff rate in DS-CDMA cellular systems)

  • 조무호;김광식;조경록
    • 한국통신학회논문지
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    • 제22권8호
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    • pp.1659-1667
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    • 1997

  • In DS-CDMA cellular systems, using the same frequency channel at the adjacent cells simultaneously makes soft handoff possible. In soft handoff, mobiles use multiple radio resources for the space diversity of signal in the overlapped region. The previous traffic models of hard handoff are not applicable to the system with soft handoff due to switching radio channels in that region. The handoff rate can be calculated by the mobility of mobiles, which is a function of the size and shape of a cell, and the speed and density of the mobiles. In this paper, we propose an analytical traffic model to study the soft handoff rate. We assume that the system uses a two-way handoff scheme for practical purposes, which connects only two cells to a mobile during soft handoff. We performed a computer simulation to confirm the accuracy of the proposed soft handoff model. The simulation results show good agreement with the analytical model.

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Advanced peri-implantitis cases with radical surgical treatment

  • McCrea, Shane J.J.
    • Journal of Periodontal and Implant Science
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    • 제44권1호
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    • pp.39-47
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    • 2014

  • Purpose: Peri-implantitis, a clinical term describing the inflammatory process that affects the soft and hard tissues around an osseointegrated implant, may lead to peri-implant pocket formation and loss of supporting bone. However, this imprecise definition has resulted in a wide variation of the reported prevalence; ${\geq}10%$ of implants and 20% of patients over a 5- to 10-year period after implantation has been reported. The individual reporting of bone loss, bleeding on probing, pocket probing depth and inconsistent recording of results has led to this variation in the prevalence. Thus, a specific definition of peri-implantitis is needed. This paper describes the vast variation existing in the definition of peri-implantitis and suggests a logical way to record the degree and prevalence of the condition. The evaluation of bone loss must be made within the concept of natural physiological bony remodelling according to the initial peri-implant hard and soft tissue damage and actual definitive load of the implant. Therefore, the reason for bone loss must be determined as either a result of the individual osseous remodelling process or a response to infection. Methods: The most current Papers and Consensus of Opinion describing peri-implantitis are presented to illustrate the dilemma that periodontologists and implant surgeons are faced with when diagnosing the degree of the disease process and the necessary treatment regime that will be required. Results: The treatment of peri-implantitis should be determined by its severity. A case of advanced peri-implantitis is at risk of extreme implant exposure that results in a loss of soft tissue morphology and keratinized gingival tissue. Conclusions: Loss of bone at the implant surface may lead to loss of bone at any adjacent natural teeth or implants. Thus, if early detection of peri-implantitis has not occurred and the disease process progresses to advanced peri-implantitis, the compromised hard and soft tissues will require extensive, skill-sensitive regenerative procedures, including implantotomy, established periodontal regenerative techniques and alternative osteotomy sites.

  • https://doi.org/10.5051/jpis.2014.44.1.39 인용 PDF KSCI