• 대한소아치과학회지
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• 제26권3호
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• pp.479-485
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• 1999

복합레진을 이용한 수복은 재료의 낮은 강도와 중합수축으로 인한 변연 누출 그리고 상아질과의 결합력 등으로 인해 제한된 범위에서만 사용되었으나, 최근 물성의 향상 및 상아질 결합제의 발달로 심미수복이 필요한 여러 부위에 이용되고 있다. 반직접법을 이용한 레진 인레이는 와동의 크기가 너무 크거나 직접 수복이 곤란한 경우 사용될 수 있으며, 어린 환자의 영구구치 수복시 적절한 비용으로 가급적 오랫동안 보철치료를 받지 않고 사용할 수 있도록 한다. 반직접법의 장점으로는 중합수축으로 인한 변연누출이 적고, 2차 중합을 통해 중합도가 증가하여 강도가 증가되며, 간접법시 필요한 기공실 과정이 불필요하여 1회의 내원으로 치료 가능하다는 것 등이 있다. 본 증례는 심미적 치료를 원하는 환자의 구치부 수복시 반직접법을 이용한 레진 인레이를 사용하여 양호한 치료결과를 얻었기에 이를 보고하는 바이다.

• Structural Engineering and Mechanics
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• 제64권4호
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• pp.427-436
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• 2017

Concrete technologists have used ultrasonic pulse velocity test for decades to evaluate the properties of concrete. However, the presented research work focuses on the use of ultrasonic pulse velocity test to study the degradation in steel-concrete bond subjected to increasing loading. A detailed experimental investigation was conducted by testing five identical beam specimens under increasing loading. The loading was increased from zero till failure in equal increments. From the experimentation, it was found that as the reinforced concrete beams were stressed from control unloaded condition till complete failure, the propagating ultrasonic wave velocity reduced. This reduction in wave velocity is attributed to the initiation, development, and propagation of internal cracking in the concrete surrounding the steel reinforcement. Using both direct and semidirect methods of testing, results of reduction in wave velocity with evidence of internal cracking at steel-concrete interface are presented. From the presented results and discussion, it can be concluded that the UPV test method can be successfully employed to identify zones of poor bonding along the length of reinforced concrete beam. The information gathered by such testing can be used by engineers for localizing repairs thereby leading to saving of time, labor and cost of repairs. Furthermore, the implementation strategy along with real-world challenges associated with the application of the proposed technique and area of future development have also been presented.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2001년도 춘계학술대회
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• pp.235-237
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• 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.