• 대한치과의사협회지
• /
• 제49권5호
• /
• pp.279-285
• /
• 2011

Currently there is no dental ceramic material can be used in all dental situations need to be restored. However, in view of recent clinical reports, the most viable alternative is zirconia ceramic. Clinical success of dental zirconia restorations strongly depends on proper selection of materials, accurate laboratory procedure and final cementation, which can be achievable with the correct understanding of zirconia. As dental materials, zirconia ceramics have a very bright future, because they are being used increasingly in the anterior region as implant fixtures, as well as crown and bridge restorations and implant abutments. Many dental ceramics showing poor clinical performance have been gone from the dental market. However, in terms of outstanding mechanical properties and esthetic nature, new dental materials can replace zirconia ceramics will not be available in the foreseeable future.

• 대한치과의사협회지
• /
• 제53권3호
• /
• pp.195-200
• /
• 2015

Cementation is the last procedure and an important factor to access successful fixed prosthodontic treatment. Even though there are many kinds of luting materials in dental field, the resin cements are popularly used in now. Metals, polymers and ceramics are used as a material of fixed dental prosthesis. The bonding mechanisms between teeth and fixed restorations are composed of mechanical and chemical mechanism. In dentistry, we are relying on mechanical bonding, but we tried to get chemical bonding and many ways are introduced. So, we have to approach luting procedure differently by the materials of prosthesis for clinical success. In this article, let us think the proper cementation ways according to each prosthesis material.

• The Journal of Advanced Prosthodontics
• /
• 제12권6호
• /
• pp.329-337
• /
• 2020

PURPOSE. To verify the influence of computer-aided design/computer-aided manufacturing (CAD/CAM) implant-supported prostheses manufactured with cobalt-chromium (Co-Cr) and zirconia (Zr), and whether ceramic application, spark erosion, and simulation of masticatory cycles modify biomechanical parameters (marginal fit, screw-loosening torque, and strain) on the implant-supported system. MATERIALS AND METHODS. Ten full-arch fixed frameworks were manufactured by a CAD/CAM milling system with Co-Cr and Zr (n=5/group). The marginal fit between the abutment and frameworks was measured as stated by single-screw test. Screw-loosening torque evaluated screw stability, and strain analysis was explored on the implant-supported system. All analyses were performed at 3 distinct times: after framework manufacturing; after ceramic application in both materials' frameworks; and after the spark erosion in Co-Cr frameworks. Afterward, stability analysis was re-evaluated after 106 mechanical cycles (2 Hz/150-N) for both materials. Statistical analyses were performed by Kruskal-Wallis and Dunn tests (α=.05). RESULTS. No difference between the two materials was found for marginal fit, screwloosening torque, and strain after framework manufacturing (P>.05). Ceramic application did not affect the variables (P>.05). Spark erosion optimized marginal fit and strain medians for Co-Cr frameworks (P<.05). Screw-loosening torque was significantly reduced by masticatory simulation (P<.05) regardless of the framework materials. CONCLUSION. Co-Cr and Zr frameworks presented similar biomechanical behavior. Ceramic application had no effect on the biomechanical behavior of either material. Spark erosion was an effective technique to improve Co-Cr biomechanical behavior on the implant-supported system. Screw-loosening torque was reduced for both materials after masticatory simulation.

• Restorative Dentistry and Endodontics
• /
• 제45권4호
• /
• pp.50.1-50.11
• /
• 2020

Objectives: In this study, we investigated the potential of amoxicillin-loaded polymeric microspheres to be delivered to tooth root infection sites via a bioactive reparative cement. Materials and Methods: Amoxicillin-loaded microspheres were synthesized by a spray-dray method and incorporated at 2.5% and 5% into a mineral trioxide aggregate cement clinically used to induce a mineralized barrier at the root tip of young permanent teeth with incomplete root development and necrotic pulp. The formulations were modified in liquid:powder ratios and in composition by the microspheres. The optimized formulations were evaluated in vitro for physical and mechanical eligibility. The morphology of microspheres was observed under scanning electron microscopy. Results: The optimized cement formulation containing microspheres at 5% exhibited a delayed-release response and maintained its fundamental functional properties. When mixed with amoxicillin-loaded microspheres, the setting times of both test materials significantly increased. The diametral tensile strength of cement containing microspheres at 5% was similar to control. However, phytic acid had no effect on this outcome (p > 0.05). When mixed with modified liquid:powder ratio, the setting time was significantly longer than that original liquid:powder ratio (p < 0.05). Conclusions: Lack of optimal concentrations of antibiotics at anatomical sites of the dental tissues is a hallmark of recurrent endodontic infections. Therefore, targeting the controlled release of broad-spectrum antibiotics may improve the therapeutic outcomes of current treatments. Overall, these results indicate that the carry of amoxicillin by microspheres could provide an alternative strategy for the local delivery of antibiotics for the management of tooth infections.

• 대한치과의사협회지
• /
• 제51권1호
• /
• pp.6-11
• /
• 2013

Dental ceramics is well known to have excellent esthetics, biocompatibility as well as high compressive strength. However, the fragility of ceramics against tensile and shear loads leading to the delayed fracture of micro crack on ceramic surface and the backwardness of ceramic fabrication technique limit the usage of ceramic materials in dentistry. Among all ceramic materials, zirconia has been introduced to overcome the drawback of conventional dental ceramics in the field of dentistry due to the nature of zirconia featuring proper opalescence and high fracture toughness. Also, novel manufacturing techniques enable ceramic materials to prepare high esthetic anterior and posterior all ceramic system. In this paper, it is introduced and discussed that novel techniques characterizing the bond strength between zirconia core and veneering ceramics and analyzing the fluorescence of dental ceramics in order to overcome the gap between the results of basic research and the feasibility of the results in the field of dental clinics.

• 디지털융복합연구
• /
• 제16권4호
• /
• pp.195-203
• /
• 2018

본 연구에서는 우리나라 치과임상에서 사용되고 있는 치과인상재의 종류 및 채득 방법에 대해 조사해보기 위해 실시되었으며, 설문조사는 전국치과병(의)원 치과의사를 대상으로 기관당 1부씩 자기기입식 방법을 통해 조사하였으며, 수집된 자료는 SPSS 20.0을 사용하여 통계 처리하여 분석하였다. 그 결과 인상재의 종류별 진료 내용에서는 대부분의 진료에서 부가중합형 인상재의 사용빈도가 가장 높았다. 인상채득방법은 점도에 분류에 의한 light body와 heavy body를 사용하는 흐름성이 다른 인상재를 한번에 채득하는 방법을 가장 선호하는 것을 확인할 수 있었고, 임플란트 인상채득방법에는 직접법과 간접법 모두 흐름성이 다른 두 가지 고무인상재를 한번에 채득하는 방법이 가장 선호되었다. 일반적인 특성에 따른 주조수복재와 보철물의 인상채득방법에서는 각각 연령과 임상경력에서 통계적으로 유의한 차이를 보였다. 본 연구결과는 임상에서 주로 사용되고 있는 인상재의 종류를 파악해보고 치과전문가에게 요구되는 인상재의 선호도에 따른 이론과 실무에 대한 업무개발에 도움이 될 수 있으리라 판단된다.

• 대한소아치과학회지
• /
• 제50권4호
• /
• pp.443-451
• /
• 2023

The purpose of this study was to evaluate whether the newly introduced calcium silicate-based materials with fast-setting properties could be appropriately used as basement materials in indirect pulp treatment (IPT). This was performed by quantifying the durability of adhesion between the material and composite resin, measured by the shear bond strength (SBS). Five calcium silicate-based materials, TheraCal LC^® (TLC), TheraCal PT^® (TPT), TheraBase^® (TB), Well-Root^TM PT (WPT), and Endocem^® MTA (EMTA), as well as two glass ionomer-based materials, Fuji II and Fuji II LC, were included. Specimens containing these materials were manufactured and bonded to composite resin with a universal adhesive applied in self-etch mode. The SBS values and failure modes were recorded, and the mean SBSs of the materials were compared. Both TPT and TB exhibited SBS values that were similar to TLC, while both WPT and EMTA appeared to have statistically lower SBS values. Mixed failure was commonly observed in TLC and TPT, while all WPT and EMTA samples showed cohesive failure. In comparison with TLC and TPT, more samples with cohesive failure were observed in TB, implying that this material forms a stronger bond with composite resin. Together with the ability of TB to chemically bind to dentin due to its 10-methacryloyloxydecyl dihydrogen phosphate component, TB seems to be a promising material for IPT within the limitations of this in vitro study.

• 대한치과의사협회지
• /
• 제54권6호
• /
• pp.448-456
• /
• 2016

Dental care is becoming more available on the NHI(National Health Insurance) in Korea. Especially, complete denture, partial denture, dental scaling, and dental implant has been applied by NHI from 2012 to 2014. Although, the entire nation is not eligible for the benefit now, the more dental coverage of NHI is extended, the more regulaition is tightened. Essential documents for proof of correctness of dental treatment covered by NHI are dental records and the receipt book. Summary of regal regulation about them is as follows 1. Chief complaints of patients, diagnosis, progress, and act of treatment, drugs and materials of treatment, doctor's sign, date and hour should be placed accurately on dental record 2. Dental clinic should collect patients sharing of the dental cost covered by NHI. 3. Dental clinic should keep the receipt as proof of purchase of dental drugs or materials.

• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2015년도 춘계학술대회 논문집
• /
• pp.63-63
• /
• 2015

• 대한치과의사협회지
• /
• 제48권12호
• /
• pp.893-918
• /
• 2010

This article is purposed of reviewing the development history of Japanese dental devices and instrument, and their related advertisement activities during the Japanese colonized period in Korea in early 20th century. Japanese dental devices and instrument were redesigned to accommodate their ergonomic shape above the simple imitation, and it implies the excessive desires brought them frustrations. The tragic earthquake on Sep. l, 1923, medical insurance law enforcement on Jan. 1, 1927, celebration of "Cavity prevention Day" started on Jun. 4, 1928, and the attack of Manchuria and China by Japan after 1931, all of these historical incidents become the preliminary requirement for the development of dental devices. On Nov. 1, 1937, Japanese government started to control dental materials, driving the campaigns for excluding foreign products and encourging the use of local products. In 1939, Nakajima dental manufacturers used this political and social atmosphere on their advertisement as saying "Our Nakajima's products have no compromise with the short raw materials, but only commitment to our quality". Since after 1940, the price and supply have been strongly under control, and the control group was appeared to manage all of supply and distribution of raw materials, regular price system, and specifications. At last, the Japanese national power were devastated in its production and distribution capacities, and get to the frustrated period. The main advertised dental devices and instruments in Korea during the Japanese colonized period were 1) dental chair, unit and cabinet, 2) dental x-ray, 3) compressors, 4) dental needles, 5) small instrument and carryon medical(emergency) kit, 6) oral hygiene and pyorrhea alveolaris, infrared rays, sunlight lamp, ultrashort wave treatment devices, 7)crown former, electric furnace, casting machine, articulator, electric lathe, and laboratory equipments, etc.