광조사기의 최신지견

방난심,정복영,최석근,박원서,김기덕,정지은,신정훈 대한통합치과학회 2019 대한통합치과학회지 Vol.8 No.1

As dentin bonding systems develop, resin composites are widely used as restorative materials for anterior and posterior teeth. QTH(Quartz-Tungsten-Halogen), PAC (plasma arc curing) light, LED (light emitting diode) light and laser have been developed and used since UV light was first used for light curing of resin composite in 1970. However, failure to adequately polymerize the resin composite can lead to premature failure of the restoration due to fracture, secondary caries, or excessive wear of the restoration. This review summarizes the types and characteristics of the light curing unit, the photoinitiator of the composite resin, the appropriate light intensity and time of the light curing unit for resin polymerization, the irradiation distance, the polymerization mode, and the risk of blue light. It is possible to reduce the unpolymerization of the resin restoration and increase the longevity of the resin composite restoration by appropriately using light curing unit 상아질 접착 시스템이 발전함에 따라 레진컴포짓은 전치부 및 구치부 치아의 수복 재료로 널리 사용된다. 1970년대 초반 레진컴포짓의 중합에 UV light 이 처음 사용된 이래로 QTH (Quartz-Tungsten-Halogen), PAC (Plasma arc curing) light, LED (Light emitting diode) linght 및 레이저가 광조사기로 개발되어 사용되고 있다. 레진컴포짓은 적절히 중합되지 않으면 수복물의 파절, 이차 우식, 또는 수복물의 과도한 마모로 인한 수복물의 조기 실패를 초래할 수 있다. 이 종설은 광조사기의 종류 및 특성, 레진컴포짓의 광개시제, 레진컴포짓의 중합에 효과적인 광조사기의 광도와 조사시간, 조사 거리, 중합 모드 및 청색광의 위험성에 대한 내용을 정리하였으며 이를 통해 광조사기를 적절히 사용함으로써 미중합 레진을 줄여 수복물의 수명을 연장시키는데 목적이 있다.

Change of Vickers Hardness by Cavity Depth by Kind of Visible Light-curing Units and Composite Resins

김주원,정인호 대한예방치과학회 2010 International Journal of Clinical Preventive Denti Vol.6 No.2

Objective: With result that observe several studies of ancient sages, we can know that element that get in contraction and hardness of composite resin is various. Therefore, in this study, select each one in QTH LCU, PAC LCU, LED LCU and select 3 in dental composite resin. and observing Vickers hardness by cavity depth, I wished to help that select visible light-curing unit and composite resin. Materials and Method: Dental light curing units (LCU) that use in photo-polymerization are EXCELLED 2 (JOVIDENT, Germany), MONITEX LD-105 (FOMED DENTAL INC, Taiwan) and EXCELLED 2 (JOVIDENT, Germany) three kinds and dental composite resins that use in cavity restorations are Filtek Flowⓡ (3M-ESPE Co., USA), Filtek Supremeⓡ (3M-ESPE Co., USA) and CharmFilⓡ Plus (Dentkist, Korea) three kinds. Measurement machine that use in harness measurement is MVK-H1 (Akashi, Japan). Results and Conclusion: 1. When used composite resin-Filtek Supremeⓡ and polymerized by visible light-curing units-Apollo 95 E, vickers hardness high appear on the whole. 2. When used visible light-curing units-EXCELLED2, vickers hardness by cavity depth was significance in all composite resin, but when it is composite resin, hardness change by cavity depth was less best. 3. When used Apollo 95 E, Vickers hardness by cavity depth did not appear significance in all composite resin. When used visible light-curing units-MONITEX LD-105, only Filtek Flowⓡ-composite resin significance in Vickers hardness by cavity depth, but Filtek Supremeⓡ and CharmFilⓡ plus-composite resin significance did not appear. 4. When uses all visible light-curing units and packed by composite resin of 3 kinds, significance appeared in Vickers hardness in surface (0 mm), middle (3 mm), base (6 mm) of cavity.

레진기질과 생체활성 필러에 따른 콤포짓트레진의 특성

이용근,임범순,김철위 大韓齒科器材學會 2003 대한치과재료학회지 Vol.30 No.2

In dentistry, since composite resins are used to restore teeth, their chemical and physico-mechanical characteristics should be similar to those of natural tooth. The mineral phase of bone and teeth is mainly hydroxyapatite. Therefore, synthetic hydroxyapatite would seem a good choice as an inorganic filler to he used in dental restoration or bone implant. The purpose of this study was to gain more insight into the possibility of the bioactive filler incorporated composite resin as restorative material, limns; material or pulp capping material through the evaluation of mechanical properties and cytotoxicity. Bioactive fillers such as apatite-wollastonite (AW) glass ceramic, bioglass (BG) and hydroxyapatite (HA) powders, and conventional glass fillers were incorporated into light-curing resin matrices composed of Bis-GMA and TEGDMA (6:4 by wt.), Bis-GMA and HEMA (6:4 by wt.), Bis-GMA, HEMA and TEGDMA (3:4:3 by wt.). and UDMA and TEGDMA (6:4 by wt.). Compressive, diametral tensile and flexural strength of light-cured specimens immersed in 37℃ DW for 24 hours was measured. Cytotoxicity by MTT method was also evaluated. When Bis-GMA and TEGDMA mixture was used as the resin matrix, compressive, diametral tensile and flexural strength of bioactive filler incorporated composite resin was 17.72∼128.22 ㎫. 39.57∼84.46 ㎫ and 21.35∼57.36 ㎫, respectively. When Bis-GMA and HEMA mixture was used as the resin matrix, BG filler incorporated composite resin did not cure, and the highest compressive and diametral tensile strength of bioactive filler incorporated composite resins was 40.24 ㎫ and 35.30 ㎫, respectively. When Bis-GMA, HEMA and TEGDMA mixture was used as the resin matrix, BG filler incorporated composite resin did not cure, and three strength values were highest after incorporating HA filler. When UDMA and TEGDMA mixture was used as the resin matrix, compressive, diametral tensile and flexural strength of bioactive filler incorporated composite resin was 38.61∼137.31 ㎫, 32.59∼110.47 ㎫ and 17.10∼48.70 ㎫, respectively. Generally, cytotoxicity of bioactive filler incorporated composite resin was higher than those of conventional glass filler incorporated resins. From the above result, mechanical properties of bioactive filler incorporated composite resins made of conventional Bis-GMA, UDMA and TEGDMA matrices were moderate; however, those of HEMA-incorporated matrices were low.

Effects of 3 different light-curing units on the physico-mechanical properties of bleach-shade resin composites

Farzad Azin,Kasraei Shahin,Haghi Sahebeh,Masoumbeigi Mahboubeh,Torabzadeh Hassan,Panahandeh Narges 대한치과보존학회 2022 Restorative Dentistry & Endodontics Vol.47 No.1

Objectives This study investigated the microhardness, flexural strength, and color stability of bleach-shade resin composites cured with 3 different light-curing units. Materials and Methods In this in vitro experimental study, 270 samples were fabricated of bleach and A2 shades of 3 commercial resin composites (Point 4, G-aenial Anterior, and Estelite Sigma Quick). Samples (n = 5 for each trial) were cured with Bluephase N, Woodpecker LED.D, and Optilux 501 units and underwent Vickers microhardness and flexural strength tests. The samples were tested after 24 hours of storage in distilled water. Color was assessed using a spectrophotometer immediately after preparation and 24 hours after curing. Data were analyzed using 3-way analysis of variance and the Tukey test (p ≤ 0.001). Results Samples cured with Optilux exhibited the highest and those cured with LED.D exhibited the lowest microhardness (p = 0.023). The bleach shade of Point 4 composite cured with Optilux displayed the highest flexural strength, while the same composite and shade cured with Sigma Quick exhibited the lowest (p ≤ 0.001). The color change after 24 hours was greatest for the bleach shade of G-aenial cured with Bluephase N and least for the A2 shade of Sigma Quick cured with Optilux (p ≤ 0.001). Conclusions Light curing with polywave light-emitting diode (LED) yielded results between or statistically similar to those of quartz-tungsten-halogen and monowave LED in the microhardness and flexural strength of both A2 and bleach shades of resin composites. However, the brands of light-curing devices showed significant differences in color stability. Objectives This study investigated the microhardness, flexural strength, and color stability of bleach-shade resin composites cured with 3 different light-curing units. Materials and Methods In this in vitro experimental study, 270 samples were fabricated of bleach and A2 shades of 3 commercial resin composites (Point 4, G-aenial Anterior, and Estelite Sigma Quick). Samples (n = 5 for each trial) were cured with Bluephase N, Woodpecker LED.D, and Optilux 501 units and underwent Vickers microhardness and flexural strength tests. The samples were tested after 24 hours of storage in distilled water. Color was assessed using a spectrophotometer immediately after preparation and 24 hours after curing. Data were analyzed using 3-way analysis of variance and the Tukey test (p ≤ 0.001). Results Samples cured with Optilux exhibited the highest and those cured with LED.D exhibited the lowest microhardness (p = 0.023). The bleach shade of Point 4 composite cured with Optilux displayed the highest flexural strength, while the same composite and shade cured with Sigma Quick exhibited the lowest (p ≤ 0.001). The color change after 24 hours was greatest for the bleach shade of G-aenial cured with Bluephase N and least for the A2 shade of Sigma Quick cured with Optilux (p ≤ 0.001). Conclusions Light curing with polywave light-emitting diode (LED) yielded results between or statistically similar to those of quartz-tungsten-halogen and monowave LED in the microhardness and flexural strength of both A2 and bleach shades of resin composites. However, the brands of light-curing devices showed significant differences in color stability.

아르곤 레이저와 가사광선의 복합레진 및 Glass ionomer 중합에 관한 연구

장기택,이상훈,이광수 大韓小兒齒科學會 1996 大韓小兒齒科學會誌 Vol.23 No.1

Following results were obtained after measuring microhardness value of top and bottom surface of the specimens, which were made of either light curing glass ionomer or composite resin, polymerized with visible light and argon laser varying curing time. 1. In Fuji Ⅱ-LC and Vitremer, significant difference was found in microhardness value, only in less than 10 seconds of curing time between using visible light and argon laser, and in the basis of microhardness value of the bottom surface, curing time of the argon laser takes only a half than that of visible light. 2. In Prisma, significant difference was found in microhardness value, only in less than 20 seconds of curing time between using of visible light and argon laser, and in the basis of microhardness value of the bottom surface, curing time of the argon laser takes only a half than that of visible light. 3. In Z-100, significant difference was found in microhardness value, only in less than 30 seconds of curing time between using of visible light and argon laser, and curing time of the argon laser takes only a quater than that of visible light. 4. In Clearfil, significant difference was found in microhardness value, in every each curing time between using of visible light and argon laser, and curing time of the argon laser takes only a quater than that of visible light.

3종의 간접수복용 복합레진의 굴곡강도 비교 및 표면관찰

김지환,김준태,박진영,김웅철 대한치과기공학회 2017 대한치과기공학회지 Vol.39 No.1

Purpose: The purpose of this study was to evaluate flexural strength, composite surface and fractured surface of three different indirect composite resins. Methods: Fifteen bar-shaped specimens (25mm x 2mm x 2mm) were fabricated for each FL group (Flow type and Light curing) and PLP group (Putty type and Light, Pressure curing) and PL group (Putty type and Light curing) according to manufacturer’s instructions and ISO 10477. Fabricated specimens were stored in the distilled water for 24 hours at the temperature of 37℃. Three-point bending strength test was performed to measure flexural strength using universal testing machine at a crosshead speed of 1mm/min (ISO 10477). Surface and fractured surface of specimens were observed by digital microscope. Results were analyzed with Kruskal-wallis tests (α = 0.05). Results: Mean (SD) of three different indirect composite resins were 83.38 (6.67) MPa for FL group, 139.90(16.53) MPa for PLP group and 171.72(16.74) MPa for PL group. Flexural strength were statistically significant (p<0.05). Differences were not observed at fractured surface among three groups. However, many pores over 100㎛ were observed at PL group in observing surface of specimen. Conclusion: Flexural strength of composite resins was affected by second polymerization method and content of inorganic filler.

광 전달 쐐기를 이용한 중합 방법이 레진 충전물의 미세 누출과 미세 경도에 미치는 효과

김종수,김용기,서용석 大韓小兒齒科學會 1998 大韓小兒齒科學會誌 Vol.25 No.4

The purpose of this study was to test the hypothesis that the more thorough cure of lightactivated composite resin could be obtained if a new way of delivering the light source deep through the resin body is developed when compared to the conventional bulk cure or incremental cure. Using cylindrical resin blocks and natural teeth, various curing conditions were tested for their effects on the degree of microleakage and microhardness. Data were analyzed statistically using One-Way ANOVA and Scheff's Multiple Range test. The results of the present study were as follows: 1. The increment of reduction in microhardness with depth was shown to be higher in group Ⅰ and Ⅱthan in group Ⅱand Ⅴ. 2. At the level of lower inner surface and the bottom surface, significantly lower micrehardness values were obtained in group I and Ⅱ when compared to group Ⅲ, Ⅳand Ⅴ. Group Ⅳshowed the lowest value among three groups (Ⅲ,Ⅳ,Ⅴ) representing the only statistically significant difference from group Ⅴ(p<.05). 3. Differences between groups in the degree of microleakage detected were shown to be statistically significant (p<.05) with the exception of group Ⅳ and Ⅴ at both occlusal and gingival margins. 4. Based upon the above-mentioned results, commonly cited recommendation of incremental curing is strongly supported and the light-transmitting wedge insertion method can be considered as a effective and feasible clinical procedure for the better curing of composite resin. However, more studies under a variety of conditions should be compoeted before this method is applied actually to the clinical setting.

Degree of conversion of resin composite cured by light through a translucent fiber posts

Urapepon, Somchai The Korean Academy of Prosthodonitics 2014 The Journal of Advanced Prosthodontics Vol.6 No.3

PURPOSE. This study evaluated the depth of cure of resin composite cured by light through a translucent fiber post. MATERIALS AND METHODS. The opaque plastic tubes in various lengths of 2, 4, 6, 8, 10, 12, 14 mm. were filled with resin composite in which two different translucent fiber posts were inserted into the center and photo-polymerized for 40 seconds. The degree of conversion of the cured composite at bottom surface were examined using Fourier transform infrared attenuated total reflection spectrometer (FTIR/ATR) at 0.1, 0.5 and 1.0 mm apart from the post surface. RESULTS. The degree of conversion of the 0.1 mm, 0.5 mm, 1.0 mm apart from the post surface was highest at the 2 mm level and continuously decreased when the distance from the light source was increased and drastically decreased when the depth from the top of the post was greater than 4-6 mm. For each level, the highest degree of conversion was at 0.1 mm from the post surface and decreased continuously when the distance apart from the post surface was increased. CONCLUSION. The quantity of light transmission depends on the type of post and the light transmission capability of the post, especially after 4-6 mm depth and the area further apart from the post surface, are insufficient for clinical light activation of resin composite.

광중합 Glass lonomer Cement의 결합 강도에 대한 실험적 연구

김보혜,손흥규 大韓小兒齒科學會 1993 大韓小兒齒科學會誌 Vol.20 No.2

The purpose of study was to compare bond strength of Light-cured Glass Ionomer Cement with those of Chemically-cured Glass Ionomer Cement and Composite Resin to enamel and dentin surface. Each extracted molars, the buccal surfaces of which were flattened, were divided into two groups, so that 40 teeth their enamel exposed and the other 40 had their dentin exposed. The materials used were: 1) FujiⅡ LC(Light-cured Glass Ionomer Cement) 2) FujiⅡ&Shofu G.I typeⅡ(Chemically-cured Glass Iomomer Cement) 3) Silux Plus(Composite Resin) Each of the materials was applied to the exposed surface of 10 teeth by insertion into a cylindericalshaped matrix which is 3mm diameter and 2mm in height. The completed specimens were stored at 37。c under 100% humidity for 24 hours: then the shear bond strength of each material to enamel and dentin surface were measured with Instron universal testing machine. The following results were obtained: 1. Bond strength to enamel surface increased in order of Shofu G.I typeⅡ, FujiⅡ, FujiⅡLC, and Silux Plus. Statistical significance was obserbed except for Shofu G.I typeⅡ and FujiⅡ, which are chemically-cured materials(p<0.01). 2. Bond strenght to dentin surface increased in order of Shofu G.I typeⅡ, FujiⅡ, Silux Plus, FujiⅡLC. There was statistical significance(p<0.05). 3. Bond strength to enamel surface was greater than that to dentin. There was statistical significance(p<0.01). From such results, it can be concluded that when Glass Ionomer Cement is used for esthetic restoration, light-cured type, which has greater bond strenth to tooth structure, is preferred to chemically-cured type.

Errors in light-emitting diodes positioning when curing bulk fill and incremental composites: impact on properties after aging

Balhaddad Abdulrahman A.,Garcia Isadora M.,Maktabi Haifa,Ibrahim Maria Salem,Alkhubaizi Qoot,Strassler Howard,Collares Fabrício M.,Melo Mary Anne S. 대한치과보존학회 2021 Restorative Dentistry & Endodontics Vol.46 No.4

Objectives This study aimed to evaluate the effect of improper positioning single-peak and multi-peak lights on color change, microhardness of bottom and top, and surface topography of bulk fill and incremental composites after artificial aging for 1 year. Materials and Methods Bulk fill and incremental composites were cured using multi-peak and single-peak light-emitting diode (LED) following 4 clinical conditions: (1) optimal condition (no angulation or tip displacement), (2) tip-displacement (2 mm), (3) slight tip angulation (α = 20°) and (4) moderate tip angulation (α = 35°). After 1-year of water aging, the specimens were analyzed for color changes (ΔE), Vickers hardness, surface topography (Ra, Rt, and Rv), and scanning electron microscopy. Results For samples cured by single-peak LED, the improper positioning significantly increases the color change compared to the optimal position regardless of the type of composite (p < 0.001). For multi-peak LED, the type of resin composite and the curing condition displayed a significant effect on ΔE (p < 0.001). For both LEDs, the Vickers hardness and bottom/top ratio of Vickers hardness were affected by the type of composite and the curing condition (p < 0.01). Conclusions The bulk fill composite presented greater resistance to wear, higher color stability, and better microhardness than the incremental composite when subjected to improper curing. The multi-peak LED improves curing under improper conditions compared to single-peak LED. Prevention of errors when curing composites requires the attention of all personnel involved in the patient's care once the clinical relevance of the appropriate polymerization reflects on reliable long-term outcomes.