Application to Frequency Domain Optical Coherence Tomography (OCT) to Dental composite resin restored tooth Sang

전상미,이영희,지형준,조혜중,김서진,김혜은,SUNQIAOCHU,안규현,최홍란,김옥준 대한구강악안면병리학회 2016 대한구강악안면병리학회지 Vol.40 No.4

Composite resins are developed as restorative materials to improve esthetics and mechanical properties. To improve the physical properties of resin material, resin filler have to be added. However, no imaging method is adopted for resin filler distribution. Optical coherence tomography (OCT) is a optical imaging technique to delineate microscopic structures within biological tissue. The OCT application to dental composites resin and its filler is not described yet. So, this new and advanced optical method is needed for clinical application for evaluation of dental composite resin. To analyze the spatial distribution of dental composite resin and to evaluate the resin restoration in cavity, frequency domain optical coherence tomography (FD-OCT) was used for their analysis. Resin restored tooth was prepared. For morphological observation, serially sectioned teeth, conventional X-ray taking and micro computed-tomography (CT) images were compared with OCT images. The experiment has done to evaluate the success of the resin restoration using 3 dimensional structure OCT image. In this research, OCT is evaluated as a new technique to image resin restoration. The evaluation of resin restored tooth was performed by OCT. Inappropriate restoration such as marginal adaptation, large porosities, internal integrity and poor contour could be detected. Resin filler also could be checked by OCT. The distribution, number, regularity and size of resin filler can be differentiated from several commercial products. Considering the characteristics of the OCT, it can be used to evaluate the defects of resin restoration, resin filler distribution, and internal integrity between resin material and tooth structure. The OCT can be considered to be a new and advanced method for the evaluation of resin restorations.

치과용 콤포짓트 레진의 물성에 관한 비교연구

김재찬,김철위 大韓齒科器材學會 1990 대한치과재료학회지 Vol.17 No.2

The purpose of this study was to evaluate the characteristics of eight commercially available chemically activated composite resins (CT, HP, LC, PFQ, MR, SR-R, P-10, and BF-II) and ten light activated comkposite resins (BFM, DR, GT, LFA, SL, SP, AD-II, BF-I, EP and LFP) being using in Korea. The following properties were studied: surface hardness, diametral tensile strength, surface roughness, solubility and water sorption, differential thermal analytical properties. These tests were performed according to the modified methods of ISO 4049 and ANSI/ADA Specification No. 27. From the experiments, the following results can be drawn: 1. The surface hardness value of the chemically activated composite resins showed considerable differences among to the products, but there was no significant differences among the light activated composite resins. 2. The diametral tensile strength of the composite resins showed considerable difference among to the products, and the light activated composite resins showed a higher strength than that of the chemically activated resins. 3. Surface roughness values (Ra) and the maximum peak/valley values (Rtm) for the light activated composite resins showed considerably lower values, and the higher values was attained for the chemically activated resins. 4. Water sorption of the light activated composite resins was considerably higher than that of the chemically activated resins, and the solubility of the light activated composite resins was significantly higher than that of the chemically activated resins. 5. The slightly exothermic temperature curves of the composite resins proceeded at 150℃∼188℃, and the broad endothermic temperature curves were appeared at 380℃∼494℃.

OCT 광학기기의 레진 컴파짓 수복평가의 응용

Sang Mi Jeon,Young Hee Lee,Hyeong Joon Ji,Hye Joung Cho,Seo Jin Kim,Hye Eun Kim,SUN QIAOCHU,Kyu Hyeon Ahn,Hong Ran Choi,Ok Joon Kim 대한구강악안면병리학회 2016 대한구강악안면병리학회지 Vol.40 No.4

Composite resins are developed as restorative materials to improve esthetics and mechanical properties. To improve the physical properties of resin material, resin filler have to be added. However, no imaging method is adopted for resin filler distribution. Optical coherence tomography (OCT) is a optical imaging technique to delineate microscopic structures within biological tissue. The OCT application to dental composites resin and its filler is not described yet. So, this new and advanced optical method is needed for clinical application for evaluation of dental composite resin. To analyze the spatial distribution of dental composite resin and to evaluate the resin restoration in cavity, frequency domain optical coherence tomography (FD-OCT) was used for their analysis. Resin restored tooth was prepared. For morphological observation, serially sectioned teeth, conventional X-ray taking and micro computed-tomography (CT) images were compared with OCT images. The experiment has done to evaluate the success of the resin restoration using 3 dimensional structure OCT image. In this research, OCT is evaluated as a new technique to image resin restoration. The evaluation of resin restored tooth was performed by OCT. Inappropriate restoration such as marginal adaptation, large porosities, internal integrity and poor contour could be detected. Resin filler also could be checked by OCT. The distribution, number, regularity and size of resin filler can be differentiated from several commercial products. Considering the characteristics of the OCT, it can be used to evaluate the defects of resin restoration, resin filler distribution, and internal integrity between resin material and tooth structure. The OCT can be considered to be a new and advanced method for the evaluation of resin restorations.

Wear resistance of indirect composite resins used for provisional restorations supported by implants

Akimasa Tsujimoto,Carlos Jurado,Jose Villalobos-Tinoco,Wayne Barkmeier,Nicholas Fischer,Toshiki Takamizawa,Mark Latta,Masashi Miyazaki 대한치과보철학회 2019 The Journal of Advanced Prosthodontics Vol.11 No.4

PURPOSE. The aim of this study was to investigate simulated localized and generalized wear of indirect composite resins used for implant supported provisional restorations. MATERIALS AND METHODS. The study investigated ten indirect composite resins. Two kinds of wear were simulated by 400,000 cycles in a Leinfelder-Suzuki (Alabama) machine. Localized wear was simulated with a stainless-steel ball bearing antagonist and generalized with a flat-ended stainless-steel cylinder antagonist. The tests were carried out in water slurry of polymethyl methacrylate beads. Wear was measured using a Proscan 2100 noncontact profilometer in conjunction with Proscan and AnSur 3D software. RESULTS. Both localized and generalized wear were significantly different (P<.05) among the indirect composite resins. SR Nexco and Gradia Plus showed significantly less wear than the other indirect composite resins. The rank order of wear was same in both types of wear simulation. CONCLUSION. Indirect composite resins are recommended when a provisional implantsupported restoration is required to function in place over a long period. Although only some indirect composite resins showed similar wear resistance to CAD/CAM composite resins, the wear resistance of all the indirect composite resins was higher than that of bis-acryl base provisional and polymethyl methacrylate resins.

디지털 이미지 상관법을 이용한 Methacrylate기질과 Silorane기질 복합레진의 치아 수복 시 중합수축거동

박정훈,최낙삼 한국복합재료학회 2020 Composites research Vol.33 No.3

The polymerization shrinkage behavior of dimethacrylate-based composite (Clearfil AP-X, Kuraray) and silorane-based composite (Filtek P90, 3M ESPE) used for dental composite restorations was measured using digital image correlation method. The stress distribution on the surface of specimen was calculated by finite element analysis with equivalent elastic modulus and was compared with the measured shrinkage distribution. Camera images were monitored by a CCD camera during and after the irradiation of light. As a result of the DIC analysis, a non-uniform shrinkage distribution was observed in both composite resins, and the resin core inside the ring specimen had free flowability, leading to in greater shrinkage strain than the resin/ring interfacial region. It was observed that as the distance from the center of the resin increased, the radial average shrinkage strain decreased. The radial average shrinkage strain during light irradiation occurred to be 33% for P90 and 57% for AP-X of the entire strain at the end of the test. The shrinkage behavior of P90 and AP-X was measured to be significantly different from each other during light irradiation. In the resin near the resin/ring interface, it was confirmed that the tensile strain rapidly formed to increase after light irradiation, causing a tensile stressed, interface weak. 치과용 복합레진 Filtek P90 (3M ESPE, USA)과 Clearfil AP-X (Kuraray, Japan)를 대상으로 디지털 이미지 상관법을 이용하여 광중합 시 발생하는 수축거동을 관찰하고 등가탄성계수를 적용한 유한요소해석을 통해 시편표면의 응력분포를 산출하여 수축률분포와 비교하였다. 광조사 중과 광조사 후의 촬영 조건을 달리하여 CCD 카메라를 이용한 시편의 변형사진을 획득하고 디지털 이미지 상관분석을 하였다. DIC 분석 결과 상기의 복합레진 모두에서, 비균일한 수축변형률 분포가 관찰되었으며 링시편 내부의 레진 중심부가 자유로운 유동성으로 레진/링의계면부보다 큰 수축 변형률이 발생하였다. 레진의 중심으로부터 거리가 멀어질수록 반경방향 평균수축률은 감소하였으며, 광조사동안에 발생한 반경방향 평균수축률은 경화시험종료(10 min) 후 발생한 반경방향 평균수축률 값을 기준으로 P90은 33%, AP-X는 57% 수준이었다. P90과 AP-X가 광조사 중의 수축거동이 크게 달랐음을 확인하였다. 레진/링의 계면부에 가까운 레진에서는 광조사 후에 인장변형률이 급격히 커져서 계면부가 인장응력을 받아취약하게 됨을 확인하였다.

광중합형 복합레진 및 치면열구전색 건강보험 급여화에 대한 인식에 따른 치과위생사의 직무만족도

문혜영,김은애,김지은,양윤형,이연경,전미경 한국치위생감염관리학회 2020 한국임상치위생학회지 Vol.8 No.2

Objectives: This study aimed to investigate the recognition of light curing composite resin filling and sealant by national health insurance coverage and identify differences in the job satisfaction of dental hygienists. Methods: A self-reported online questionnaire (Google form) was distributed to dental hygienists currently working in dentistry who consented to participate in the study. A total of 214 questionnaires were analyzed. Results: “The increase in health benefits at low prices” contributed the most (64%) to satisfaction with the conversion of light curing composite resin's medical expenses. The factor most affecting satisfaction with the implementation of pits and fissure sealing was the increase in health coverage at low prices (48.6%). Finally, job satisfaction was the highest among dental hygienists who wanted to expand national health insurance coverage items. Conclusions: Dental hygienists were found to be satisfied with the coverage of light curing composite resin filling and sealant. The expansion of coverage items among dental hygienists' work is an opportunity to improve job satisfaction among dental hygienists.

치과용 복합레진에 대한 첨가제의 영향

정진희,홍광일,고재영,안세영,안광덕,한동근 대한의용생체공학회 2002 의공학회지 Vol.23 No.2

2.2-Bis[P-(2-hydroxy-3-methacryloyloxypropoxyl)phenol]propane (Bis-GMA)는 광중합형 치과용 고분자 복합레진의 다관능성 유기물로 널리 사용되고 있다. Bis-GMA는 두 개의 히드록시기를 가지고 있어서 구강내에서 광중합되는 복합레진의 물흡수를 야기시켜 장기간 점진적으로 심미성이 감소하고 결국엔 복합레진의 기계적 특성까지 저하시키게 된다. 본 연구에서는 최종제품의 내구성과 저장안정성을 향상시키기 위하여 복합레진에 광안정제와 산화방지제를 첨가제로 사용하였다. 먼저 Tinuvin P의 광안정제를 첨가하면 색변화가 큰 것을 볼 수 있었으나 Irganox 245의 산화방지제를 첨가하였을 때 색안정성이 향상됨을 알 수 있었다. 또한 Tinuvin P와 Irganox 245가 동시에 첨가되었을 때 색안 정성이 향상되며 시료의 가속화 실험 전과 가속화 후 간접인장강도와 같은 기계적 성질도 크게 감소되지 않았다. 따라서 치과용 복합레진의 제조에 있어서 첨가제인 Tinuvin P와 Irganox 245가 각각 0.5% 및 0.1% 첨가되었을 때 내구성 및 색안정성이 향상되었으며 나아가 저장 안정성도 향상됨을 확인할 수 있었다. Bis-GMA, 2.2-bis[p(2-hydroxy-3-methacryloyloxypropokyl)phenyl]Propane, is an essential component as a multifunctional methacrylate prepolymer in the light-curable polymeric dental composite resins. Two hydroxyl groups of the Bis-GMA molecule are considered to induce water sorption of the photocured composite resin in a mouth, resulting in gradual long-term deterioration of aesthetics and mechanical properties of the composite resins. In this study, some additives such as light stabilizer and antioxidant were added to composite resins to promote durability and storage stability of the last product. First of all, color change increased as a light stabilizer. Tinuvin P, was added to the composed resins and color stability was improved as an antioxidant, Irganox 245, was added to ones. In addition, when Tinuvin P and Irganox 245 were added together to the composed resins. the color stability was enhanced and mechanical properties such as diametral tensile strength before and after acceleration tests were also not greatly decreased. Therefore, when 0.5 weight Percent of Tinuvin P and 0.1 weight percent of Irganox 245 were added together to dental composite resins. the durability and color stability were enhanced, and furthermore the storage stability was also improved for the composed resins.

Difference in color and color parameters between dental porcelain and porcelain-repairing resin composite

Kim, Sung-Hee,Lee, Yong-Keun,Lim, Bum-Soon,Rhee, Sang-Hoon,Yang, Hyeong-Cheol Wiley Subscription Services, Inc., A Wiley Company 2006 Journal of biomedical materials research. Part B, Vol.b76 No.1

<P>The objective of this study was to measure the differences in color and color parameters between dental porcelain and porcelain-repairing resin composites. The colors of three shades (A2, A3, A3.5) of one brand of dental porcelain, three original shades (A2, A3, A3.5), and three combinations (A2/A3, A3/3.5, A2/A3.5) of three brands of porcelain-repairing resin composites (ABT, FSP, TCR) were measured. The specimens were 2 mm thick, and 1 mm of each shade was layered to make combined shades. Differences in color (ΔE<EM><SUB>ab</SUB><SUP>*</SUP></EM>), lightness (ΔL*), chroma (ΔC<EM><SUB>ab</SUB><SUP>*</SUP></EM>), and hue (ΔH<SUP>*</SUP>) between porcelain and resin composite were calculated. Color difference was calculated as ΔE<EM><SUB>ab</SUB><SUP>*</SUP></EM> = (ΔL*<SUP>2</SUP> + Δa*<SUP>2</SUP> + Δb*<SUP>2</SUP>)<SUP>1/2</SUP>, chroma difference was calculated as ΔC<EM><SUB>ab</SUB><SUP>*</SUP></EM> = (Δa*<SUP>2</SUP> + Δb*<SUP>2</SUP>)<SUP>1/2</SUP>, and hue difference was calculated as ΔH<EM><SUB>ab</SUB><SUP>*</SUP></EM> = (ΔE<EM><SUB>ab</SUB><SUP>*2</SUP></EM> − ΔL*<SUP>2</SUP> − ΔC<EM><SUB>ab</SUB><SUP>*2</SUP></EM>)<SUP>1/2</SUP>. The influence of porcelain shade, brand of resin composites, and shade of resin composites were analyzed by three-way analyses of variance, and the differential influence of color parameters on color difference was analyzed with multiple regression analysis (α = 0.05). Differences in color and color parameters were influenced by the porcelain shade, brand and shade of resin composites. The ΔE<EM><SUB>ab</SUB><SUP>*</SUP></EM> value was in the range of 2.2–16.9. The ΔE<EM><SUB>ab</SUB><SUP>*</SUP></EM> value was correlated with ΔC<EM><SUB>ab</SUB><SUP>*</SUP></EM> (standardized correlation coefficient, β = − 0.85), ΔL* (β = − 0.52), and ΔH<EM><SUB>ab</SUB><SUP>*</SUP></EM> (β = 0.08). Between the same shade designated pairs of porcelain and repairing composite, color difference was perceptible. Therefore, studies to improve the color matching between porcelain and repairing resin are recommended. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006</P>

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.

Synthesis of a Novel Spiro Orthocarbonate Containing Bisphenol-A Unit and Its Application to the Dental Composites

유선화,김창근 한국고분자학회 2010 Macromolecular Research Vol.18 No.10

Dental restorative composites containing spiro orthocarbonates (SOCs) have been studied extensively to minimize the volumetric shrinkage that occurs during polymerization. Previous reports suggested that dental composites with low volumetric shrinkage could be obtained by mixing SOC with conventional resins. However,its inclusion had adverse effects on the mechanical properties of dental composites. A novel SOC (2,2-bis-4,4'-(7-phenyl-1,4,6,9-tetraoxaspiro[4.4]nona-2-ylmethoxyphenyl)propane), SOC-N, was synthesized to overcome these adverse effects resulting from the previously developed SOCs. The mechanical strength and volumetric shrinkage of the dental composites composed of 70 wt% inorganic fillers and resin matrices containing SOC-N,2,2-bis-[4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl] propane (Bis-GMA), and triethylene glycol dimethacrylate (TEGDMA) were explored. When compared to a control resin-containing composite (Bis-GMA/TEGDMA=70/30), the volumetric shrinkage of the composite containing new resin matrix, obtained through the addition of SOC-N to the Bis-GMA/TEGDMA=70/30 mixture, was reduced gradually by increasing the SOC-N content. Furthermore, the latter sample showed better mechanical strength than the former when the resin matrix contained 30 wt% SOC-N.