A comparative study of metal artifacts from common metal orthodontic brackets in magnetic resonance imaging

Kajan, Zahra Dalili,Khademi, Jalil,Alizadeh, Ahmad,Hemmaty, Yasamin Babaei,Roushan, Zahra Atrkar Korean Academy of Oral and Maxillofacial Radiology 2015 Imaging Science in Dentistry Vol.46 No.1

Purpose: This study was performed to compare the metal artifacts from common metal orthodontic brackets in magnetic resonance imaging. Material and Methods: A dry mandible with 12 intact premolars was prepared, and was scanned ten times with various types of brackets: American, 3M, Dentaurum, and Masel orthodontic brackets were used, together with either stainless steel (SS) or nickel titanium (NiTi) wires. Subsequently, three different sequences of coronal and axial images were obtained: spin-echo $T_1$-weighted images, fast spin-echo $T_2$-weighted images, and fluid-attenuated inversion recovery images. In each sequence, the two sequential axial and coronal images with the largest signal-void area were selected. The largest diameters of the signal voids in the direction of the X-, Y-, and Z-axes were then measured twice. Finally, the mean linear values associated with different orthodontic brackets were analyzed using one-way analysis of variation, and the results were compared using the independent t-test to assess whether the use of SS or NiTi wires had a significant effect on the images. Results: Statistically significant differences were only observed along the Z-axis among the four different brands of orthodontic brackets with SS wires. A statistically significant difference was observed along all axes among the brackets with NiTi wires. A statistically significant difference was found only along the Z-axis between nickel-free and nickel-containing brackets. Conclusion: With respect to all axes, the 3M bracket was associated with smaller signal-void areas. Overall, the 3M and Dentaurum brackets with NiTi wires induced smaller artifacts along all axes than those with SS wires.

A comparative study of metal artifacts from common metal orthodontic brackets in magnetic resonance imaging

Zahra Dalili Kajan,Jalil Khademi,Ahmad Alizadeh,Yasamin Babaei Hemmaty,Zahra Atrkar Roushan 대한영상치의학회 2015 Imaging Science in Dentistry Vol.45 No.3

Purpose: This study was performed to compare the metal artifacts from common metal orthodontic brackets in magnetic resonance imaging. Material and Methods: A dry mandible with 12 intact premolars was prepared, and was scanned ten times with various types of brackets: American, 3M, Dentaurum, and Masel orthodontic brackets were used, together with either stainless steel (SS) or nickel titanium (NiTi) wires. Subsequently, three different sequences of coronal and axial images were obtained: spin-echo T1-weighted images, fast spin-echo T2-weighted images, and fluid-attenuated inversion recovery images. In each sequence, the two sequential axial and coronal images with the largest signalvoid area were selected. The largest diameters of the signal voids in the direction of the X-, Y-, and Z-axes were then measured twice. Finally, the mean linear values associated with different orthodontic brackets were analyzed using one-way analysis of variation, and the results were compared using the independent t-test to assess whether the use of SS or NiTi wires had a significant effect on the images. Results: Statistically significant differences were only observed along the Z-axis among the four different brands of orthodontic brackets with SS wires. A statistically significant difference was observed along all axes among the brackets with NiTi wires. A statistically significant difference was found only along the Z-axis between nickel-free and nickel-containing brackets. Conclusion: With respect to all axes, the 3M bracket was associated with smaller signal-void areas. Overall, the 3M and Dentaurum brackets with NiTi wires induced smaller artifacts along all axes than those with SS wires.

세라믹 자가결찰 브라켓 제거 시 파절률 및 접착제 잔존 양상의 비교

김유리(Yu Ri Kim),임성훈(Sung-Hoon Lim) 대한치과교정학회 2024 대한치과교정학회 임상저널 Vol.14 No.1

Introduction: The purpose of this study was to measure the fracture rates and adhesive remnant indices of two ceramic self-ligating orthodontic brackets after dental debonding. Methods: Clippy-C 2G (Tomy, Tokyo, Japan) and Majesty-SLC brackets (Osstem Orthodontics, Uiwang, Korea) were bonded on 72 premolars of 27 patients. Only maxillary and mandibular first premolar brackets were bonded. Debonding was done at least four weeks after the bonding using a debonding plier for Majesty-SLC brackets. After the debonding procedure, the fracture rate was examined and the resin remnants were measured using modified adhesive remnant index (ARI) scores. Results: No statistical significance in ARI scores was observed between the two brackets (P=0.101). The bracket fracture rate during debonding was significantly higher in the Clippy-C 2G brackets in maxillary premolars (P=0.002). Conclusions: The amount of residual resin remnants on the enamel surface suggested that both ceramic self-ligating brackets can be debonded safely with little damage to the enamel. Clippy-C 2G brackets for maxillary first premolars showed a significantly higher fracture rate. (Clin J Korean Assoc Orthod 2024;14(1):1-8)

교정용 브라켓과 호선 간의 마찰 저항력의 비교

서충환,정혜승,조진형,강경화 대한치과교정학회 2005 대한치과교정학회지 Vol.35 No.2

본 연구는 고정성 장치를 이용한 교정 치료에서 브라켓과 교정용 호선 사이의 활주 이동 동안 발생하는 마찰력에 디자인과 재질이 다른 각각의 브라켓과 여러 종류의 호선, 다양한 브라켓-호선 각도 등이 어떤 영향을 미치는가를 알아보기 위하여 4종의 브라켓(stainless steel twin 브라켓인 Gemini^(?), 좁은 근원심 폭경과 single bracket의 디자인이 포함된 Mini Uni-Twin^(?), metal-reinforced 세라믹 브라켓인 Clarity^(?), 세라믹 브라켓인 Transcend^(?)을 사용하고, 3종의 교정용 호선(0.016˝. 0.016×0.022˝ stainless steel호선, 0.016˝Nitinol)을 이용하여 브라켓-호선 각도를 0˚, 3˚, 9˚로 조절하면서 실험한 결과, Gemini^(?)는 유의하게 가장 낮은 정지, 운동 마찰력을 보였으며(P<0.001), Clarty^(?)는 0˚의 브라켓-호선 각도에, Transcend^(?)는 6˚와 9˚의 각도에서 유의하게 가장높은 정지, 운동 마찰력을 보였고(P<0.001), 0.016×0.022˝ stainless steel 각형 호선은 유의하게 가장 높은 정지, 운동 마찰력을 보였으며(P<0.01),0.016˝ stainless steel 원형호선은 0˚와3˚의 브라켓-호선 각도에서(P<0.01), 0.016˝ Nitinol은 6˚와9˚의 각도에서 (P<0.001)유의하게 가장 낮은 정지, 운동마찰력을 보였고 브라켓-호선 각도가 증가함에 따라 유의하게 정지, 운동마찰력도 증가 하였다(P<0.001) The object of this study was to evaluate how friction that occurs during the sliding movement of an orthodontic archwire through orthodontic brackets is differently affected by variant designs and ingredients of brackets and archwires and bracket-archwire angles. In order to simulate the situations which could occur during orthodontic treatment with fixed appliances, 4 types of brackets(Gemini^(?), a stainless steel twin bracket:Mini Uni-Twin^(?), a stainless steel bracket with a single bracket design and narrow mesio-distal width: Clarity^(?), a metal-reinforced cermic braket: T ranscend^(?), a ceramic bracket)and 3 types of orthodontic archwires (0.016˝, 0.016×0.022 stainless steel, 0.016˝ Nitinol)were used and the bracket-archwire angles were controlled as 0˚,3˚,6˚, and 9˚, Gemini^(?) significantly showed the lowest static and kinetic frictions (P<0.001). Clarity showed the highest static and kinetic frictions with a bracket-archwire angle of 0˚, and Transcend at 6˚ and 9˚(P<0.001). An 0.016×0.022˝ stainless steel rectangylar archwire significantly showed the highest static and kinetic frictions(P<0.01). The lowest static and kinetic frictions were observed when the bracket-archwire angles were 0˚ and 3˚ with 0.016˝ stainless steel round archwires(P<0.01), and 6˚ and 9˚ with 0.016 Nitinol(P<0.001). The static and kinetic frictions were increased as the bracket-archwire angles were increased(P<0.001).

교정용 브라켓과 강선 사이의 운동마찰저항력에 관한 실험적 연구

이재환,이기수 대한치과교정학회 2001 대한치과교정학회지 Vol.31 No.4

이 연구의 목적은 호선으로 유도되는 치아이동을 실험실에서 실현하는 동안 브라켓과 선재의 운동 마찰저항에 대한 브라켓 수, 브라켓 폭경, 선재 크기가 미치는 영향을 관찰하기 위한 것이다 상악 제 1, 2 소구치, 제 1 대구치와 유사한 크기의 레진 치아를 사용하였으며, 치주인대와 탄성계수가 비슷한 폴리 에테르 인상재를 사용하였다. 스테인레스 스틸 트윈 에지와이즈 브라켓으로 좁은 폭경 (2.4 mm), 중간 폭경 (3.0 mm), 넓은 폭경 (4.3 mm)을 사용하 였으며, 강선으로는 0.016, 0.018, 0.016 × 0.022, 0.019 × 0.025인치의 굵기를 사용하였고, 결찰은 합성고무링을 이용하고, 제1소구치에 부착된 좁은 폭경 브라켓 1개, 제 1, 2소구치에 부착된 2개의 중간 폭경 브라켓 및 제 1, 2소구치와 제 1 대구치에 부착된 3개의 중간 폭경 브라켓과 각 강선 사이의 운동 마찰저항력을 계측하여 다음의 결론을 얻었다. 1.좁은 폭경, 중간 폭경, 넓은 폭경 세 종류의 브라켓 모두에서 교정용 선재의 단면 크기가 증가할수록 마찰저항력도 증가하였다. 2. 0.016, 0.018인치 원형 강선은 브라켓 폭경이 증가하면 운동마찰저항력은 감소하며, 0.016 × 0.022, 0.019 × 0.025인치 각형 강선은 브라켓 폭경이 증가하면 운동마찰저항력이 증가하는 경향이 있었고 0.016인치 원형 강선과 폭경이 다른 브라켓과의 운동마찰저항력 사이에는 통계적으로 유의차가 없었다. 3.중간 폭경 브라켓의 수가 증가할수록 마찰저항력은 크게 나타났으며, 그 증가율은 브라켓의 수에 비례하였으나 정수배로 증가하지는 않았고 강선의 굵기에 따라 차이가 있었다. (주요 단어 : 운동마찰저항, 교정용 브라켓수, 브라켓 폭경, 교정용 선재) This investigation was designed to determine the effects of wire size, bracket width and the number of bracket on bracket-wire dynamic frictional resistance during simulating arch wire-guided tooth movement in vitro. For simulation of an arch wire-guided tooth movement, we simulated tooth, periodontal ligament and cancellous bone. Maxillary premolar and 1st molar were simulated as real sized resin teeth, the simulated resin teeth which its root was coated by polyether impression material which its elastic modulus is similar to periodontal ligament were embedded in steel housing with inlay wax which its elastic modulus is similar to cancellous bone. Stainless steel wires in four wire size (0.016, 0.018, 0.016 × 0.022, 0.019 × 0.023 inch) were examined with respect to three (stainless steel) bracket widths (2.4, 3.0, 4.3mm) and the number of medium bracket(one, two, three) included in the experimental assembly under dry condition. The wires were ligated into the brackets with elastomeric module. The results were as follows : 1.In all the brackets, frictional resistance increased with increase in wire size. But, statistically similar levels of frictional resistance were observed between 0.018 inch and 0.016 × 0.022 inch wires in narrow bracket and also between 0.016 inch and 0.018 inch wire in wide backet. 2.The frictional forces produced by 0.016 inch wire were statistically similar levels in all the brackets. In 0.018 inch round wire, wide bracket was associated with lower amounts of friction than both narrow and medium brackets. In 0.016 × 0.022, 0.019 × 0.025 inch rectangular wire, wide bracket produced larger friction than both narrow and medium brackets. In all the wires, narrow and medium bracket demonstrated no statistical difference in levels of frictional resistance. 3.Frictional resistance increased with increase in number of medium bracket. 0.016 inch round wire demonstrated the greatest increment in frictional resistance, followed by 0.019 × 0.025, 0.016 × 0.022 inch rectangulal wire which were similar level in increment of frictional resistance, 0.018 inch wire demonstrated the least increment. The increments of frictional resistance were not constantly direct proportion to number of bracket. ※ Key words : Dynamic frictional resistance, Number of orthodontic bracket. Bracket width. Orthodontic wire

최적구조설계를 이용한 교정브라켓 성능향상에 관한 연구

권현규,이정화,권동재,박상준,전유진 한국반도체디스플레이기술학회 2022 반도체디스플레이기술학회지 Vol.21 No.1

There has always been a demand for orthodontic treatment. Orthodontic treatment allows tooth to be arranged by flexible arch wire fixed with tooth-attached brackets. Arch wire generate constant pressure to tooth brackets which moves the teeth to proper place. When the bracket transmits force, the braced wing of the bracket may deform. Deformed tie wing will lead to lost tension of elastic ligature. Then, lacking grip between tie wing and ligature might delay the tooth movement. Furthermore, tooth brackets used for orthodontic treatment make contact with in direct oral surface and this cause feeling of irritation that comes from height of tooth braces. This study suggests an optimal teethe bracket design to make up for inconvenience by shorten the height of bracket and complement the shape of bracket to reduce strain rate using finite element analysis. As a result, new optimal design of teethe bracket indicates lower strain rate of the bracket wing and takes good effects of shorten body height in terms of convenience.

Antimicrobial Activity of TiO2-coated Orthodontic Ceramic Brackets against Streptococcus mutans and Candida albicans

F. Özy ld z,A. Uzel,I. Karaboz,M. Güden,O. Akil,H. Bulut 한국생물공학회 2010 Biotechnology and Bioprocess Engineering Vol.15 No.4

Polycrystalline alumina ceramic orthodontic brackets were coated with anatase TiO2 film via a sol-gel dip-coating method. The surface structure morphology and composition of the films were evaluated via scanning electron microscopy, atomic force microscopy, and X-ray diffraction. The antimicrobial activity of the ceramic brackets was assessed against two oral pathogens, S. mutans and C. albicans. The results demonstrated that TiO2-coated brackets exposed to low energy UV-A illumination efficiently reduced the populations of test microorganisms relative to the uncoated brackets. The reduction efficiencies were 98% for S. mutans ATCC 10449 and 93% for C. albicans ATCC 60193.

교정용 브라켓의 종류와 각도, 호선의 코팅 여부에 따른 마찰력의 비교

장태호(Tae-Ho Jang),김상철(Sang-Cheol Kim),조진형(Jin-Hyoung Cho),채종문(Jong-Moon Chae),장나영(Na-Young Chang),강경화(Kyung Hwa Kang) 대한치과교정학회 2011 대한치과교정학회지 Vol.41 No.6

본 연구의 목적은 코팅된 호선, 다양한 브라켓, 그리고 브라켓-호선 각도가 교정용 호선이 브라켓을 활주 이동하는 동안 발생되는 마찰력에 어떠한 영향을 미치는지에 대하여 평가해보는 것이었다. 고정식 장치를 이용한 교정치료 시 발생할 수 있는 상황을 시뮬레이션하기 위하여 4종류의 브라켓(금속 브라켓인 Micro-arch, 단결정 세라믹 브라켓인 Perpect Clear2, active type의 자가결찰 브라켓인 Clippy-C, passive type의 자가결찰 브라켓인 Damon3)과 5종류의 교정용 호선(0.014", 0.016", 0.016" × 0.022" inch coated Ni-Ti 호선, 0.016", 0.016" × 0.022" inch Ni-Ti 호선)이 사용되었고 브라켓-호선 각도는 각각 0˚, 3˚, 6˚, 9˚로 조절되었다. 모든 실험군에서 자가결찰 브라켓군, Micro-arch군, Perpect Clear2이 순으로 정지, 운동 마찰력이 유의하게 높았다 (p < 0.001). 0˚와 3˚의 브라켓-호선 각도에서 같은 크기의 Ni-Ti 호선은 코팅 여부에 따른 정지, 운동 마찰력의 유의한 차이가 없었으나, 3˚에서 자가결찰 브라켓군의 0.016" × 0.022" inch Ni-Ti 호선에서만 코팅된 경우에 마찰력이 유의하게 높았으며 (p < 0.001), 6˚와 9˚의 브라켓-호선 각도에서 원형과 각형 호선은 모두 같은 크기의 코팅된 호선에서 정지, 운동 마찰력이 유의하게 높았다 (p < 0.001). 코팅된 호선은 크기가 커질수록 정지, 운동 마찰력이 유의하게 높아졌다 (p < 0.001). 각형 호선은 원형 호선 보다 정지, 운동 마찰력이 유의하게 높았으나, 9˚의 브라켓-호선 각도에서 0.016" inch coated Ni-Ti 호선만은 0.016" × 0.022" inch Ni-Ti 호선보다 마찰력이 높았다 (p < 0.001). 브라켓-호선 각도가 증가함에 따라 정지, 운동 마찰력도 유의하게 높아졌으나 (p < 0.001), Micro-arch군과 Perpect Clear2군에서 0.016 inch Ni-Ti 호선과 이루는 각도 0˚, 3˚에서는 마찰력의 유의한 차이가 없었다. (대치교정지 2011;41(6):399-410) Objective: The purpose of this study was to evaluate the difference in frictional resistance among metal, ceramic, self-ligation brackets and coated or non-coated Ni-Ti archwires at various bracket-archwire angulations during the sliding movement of an orthodontic archwire, using an orthodontic sliding simulation device. Methods: Four types of bracket (Micro-arch Perpect Clear2 Clippy-C and Damon3 and 5 types of orthodontic archwire (0.014", 0.016", and 0.016" × 0.022" inch coated Ni-Ti, and 0.016" and 0.016" × 0.022" inch Ni-Ti) were used. Further, the bracket-archwire angles were set at 4 different angulations: 0°, 3°, 6°, and 9°. Results: The frictions from all the experimental groups were found to be significantly increased in order of self-ligation brackets, Micro-arch and Perpect Clear2 (p < 0.001). The presence of a coat had no effect on the friction of the same sized archwires at 0° and 3° bracket-archwire angles (p < 0.001). Coated archwires had significantly higher frictions than the same sized non-coated archwires at 6° and 9° bracket-archwire angles (p < 0.001). The frictions increased significantly as the bracket-archwire angles were increased (p < 0.001). Conclusions: The use of self-ligation brackets will be beneficial in clinical situations where a low frictional force is required. Further, in cases where crowding is not severe, the use of coated archwires should not cause problems. However, more additional explanation is required considering the fact that the damage of coated archwire and exposure of the metal portion in case of binding and notching and the effects of saliva were not taken into account. (Korean J Orthod 2011; 41(6):399-410)

녹차 및 결명자 추출물의 교정용 브라켓과 치면 사이의 경계부에서 분리된 mutans streptococci에 대한 항균작용

임성훈,서정순,윤영주,김광원,유소영,김화숙,국중기,이병래,차종희,박재윤 대한치과교정학회 2003 대한치과교정학회지 Vol.33 No.5

본 연구는 치아우식증에 관련된 Mutans streptococci 표준균주 및 임상분리 균주의 성장억제를 유도할 수 있는 천연 생약추출물을 검색하기 위하여 실시되었다. 녹차추출물은 CHMC-2032를 사용하였으며, 결명자 추출물은 50% 에탄올을 이용하여 얻었다. 이들 추출물의 Mutans streptococci 표준균주 및 교정환자들에서 브라켓과 치면 사이의 경계부에서 분리된 각각 10 균주씩의 S. mutans 및 S. sobrinus에 대한 최소성장억제농도를 액체배지 희석법으로 구하였다. 그 결과 CHMC-2032의 S. mutans 및 S. sobrinus의 표준 균주, S. sobrinus의 대부분 임상분리 균주에 대한 최소성장억제농도는 5 mg/ml이었다. 그러나 결명자 추출물에 의한 S. mutans 및 S. sobrinus에 대한 세균 성장억제 효과는 미미하였다. 본 연구 결과 치아우식증의 예방적 측면에서 결명자차보다는 녹차를 마시는 것이 유리하며, CHMC-2032를 이용하여 구강양치용액을 제조하여 사용할 경우 교정환자를 포함하여 대부분의 사람에게서 치아우식증 예방 효과가 있으리고 추정된다. Mutans streptococci is the major causative factor in dental caries. Especially, orthodontic patients with fixed appliance are a risk group for dental caries. Because fixed appliances attached on teeth may change the environment of dental plaque, the enamel decalcification or dental caries around the bracket and band is a major side effect of orthodontic treatment. The aim of this study was to search plant extracts that have antimicrobial effect on mutans streptococci. Seed-extract of Casio tora were prepared with ethanol and CHMC-2032, the leaf-extracts from Camellia sinensis extract, was obtained extract, 2 type strains and 20 clinical isolates of mutans streptococci isolated from the interface between orthodontic brackets and tooth surfaces in the orthodontic patients were used in this study. The minimal inhibitory concentration of CHMC-2032 was 5 mg/ml on the S. mutans KCTC 3065, S. sobrinus KCTC 3088, and 8 clinical isolates of S. sobrinus. However, there was no antibacterial effect of seed-extract of C. tora on mutans streptococci. These data suggest that green tea may be more effective than the tea prepared from C. tora in the prevention of enamel decalcification or dental caries around brackets.

Orthodontic bracket bonding to glazed full-contour zirconia

Kwak, Ji-Young,Jung, Hyo-Kyung,Choi, Il-Kyung,Kwon, Tae-Yub The Korean Academy of Conservative Dentistry 2016 Restorative Dentistry & Endodontics Vol.41 No.2

Objectives: This study evaluated the effects of different surface conditioning methods on the bond strength of orthodontic brackets to glazed full-zirconia surfaces. Materials and Methods: Glazed zirconia (except for the control, Zirkonzahn Prettau) disc surfaces were pre-treated: PO (control), polishing; BR, bur roughening; PP, cleaning with a prophy cup and pumice; HF, hydrofluoric acid etching; AA, air abrasion with aluminum oxide; CJ, CoJet-Sand. The surfaces were examined using profilometry, scanning electron microscopy, and electron dispersive spectroscopy. A zirconia primer (Z-Prime Plus, Z) or a silane primer (Monobond-S, S) was then applied to the surfaces, yielding 7 groups (PO-Z, BR-Z, PP-S, HF-S, AA-S, AA-Z, and CJ-S). Metal bracket-bonded specimens were stored in water for 24 hr at $37^{\circ}C$, and thermocycled for 1,000 cycles. Their bond strengths were measured using the wire loop method (n = 10). Results: Except for BR, the surface pre-treatments failed to expose the zirconia substructure. A significant difference in bond strengths was found between AA-Z ($4.60{\pm}1.08MPa$) and all other groups ($13.38{\pm}2.57-15.78{\pm}2.39MPa$, p < 0.05). For AA-Z, most of the adhesive remained on the bracket. Conclusions: For bracket bonding to glazed zirconia, a simple application of silane to the cleaned surface is recommended. A zirconia primer should be used only when the zirconia substructure is definitely exposed.