Objective:To study the effect of heat-activated nickel-titanium arch wire for orthodontic treatment on local tissue inflammation and bone destruction.Methods:Patients who received orthodontic treatment with nickel-tit...Objective:To study the effect of heat-activated nickel-titanium arch wire for orthodontic treatment on local tissue inflammation and bone destruction.Methods:Patients who received orthodontic treatment with nickel-titanium arch wire in Hancheng People's Hospital between March 2012 and October 2017 were retrospectively studied, and according to the nickel-titanium arch wire materials in history data, the patients were divided into the experimental group who used heat-activated nickel-titanium arch wire and the control group who used common nickel-titanium arch wire. 1 week after treatment, the gingival crevicular fluid was collected to determine the contents of inflammatory cytokines as well as the mRNA expression of osteoblast markers and osteoclast markers.Results: 1 week after treatment, IL-1α, IL-1β, sTREM1 and HMGB1 contents as well as RANKL, 5-LOX, LTB4, TRACP5b and ODF mRNA expression in gingival crevicular fluid of experimental group were significantly lower than those of control group whereas OPG, Wnt3a, Runx2, OC, ALP and OCIF mRNA expression were significantly higher than those of control group.Conclusion: Heat-activated nickel-titanium arch wire for orthodontic treatment can be more effective than common nickel-titanium arch wire to reduce the local tissue inflammation and inhibit the bone destruction.展开更多
Background As the only active component in final treatment phase of Tip-Edge Plus technique, the activation of nickel-titanium orthodontic archwires is one of the factors that affect the torque expression. It is neces...Background As the only active component in final treatment phase of Tip-Edge Plus technique, the activation of nickel-titanium orthodontic archwires is one of the factors that affect the torque expression. It is necessary to evaluate the mechanical properties of the nickel-titanium wire used in the final treatment phase in simulated oral environments to forecast the treatment outcomes. Methods The mechanical properties of 171 thermal nickel-titanium wires of 0.35 mm （0.014-in） in diameters with different deflection of 40 mm in length were investigated with three-point bending test. The samples were divided into 2 groups： as-received and bended groups. In the bended group, samples were divided into 7 subgroups according to the amounts of deflection and named by the canine angulations （-25~, -19~, -13~, -7~, -1~, ＋5~, ＋11~）. The deflection of wires was made by inserting the wires into the deep tunnel of Tip-Edge Plus brackets positioned in plaster casts with different canine angulations to mimic the use of nickel-titanium wires in the final treatment phase. Immersed the bended group in artificial saliva （pH 6.8） and preserved at 37.0~C. Eight durations of incubation were tested： 1 to 8 weeks. Three analogous samples of each group and subgroups were tested per week. Stiffness （YS：E） and the load-deflection characteristics of unloading plateau section were obtained. Results Significant changes in specific mechanical properties were observed in long-term immersed and large deflected wires compared with as-received groups. Both immersion time and deflection affected the mechanical properties of wires in the simulated oral environment, and the two factors had synergistic effect. In groups -25~, -19~ and -13~, stiffness （YS：E） increased then decreased and average plateau force and ratio of variance decreased then increased correspondingly at specific time. Conclusions In the final treatment phase of Tip-Edge Plus technique, the mechanical properties of nickel-titanium wire are associated with the using time and amounts of deflection and it may affect treatment outcomes. As the main reason for wire deflection, canine crown angulation plays an important role in the wire performance. It may be wise to focus on the canine crown angulations and using time in clinic with Tip-Edge Plus technique and make proper adjustment to help to make sure the treatment outcomes.展开更多
Background The shape memory effect of nickel-titanium （NiTi） archwires is largely determined by the phase transition temperature. It is associated with a reversible transformation from martensite to austenite. The a...Background The shape memory effect of nickel-titanium （NiTi） archwires is largely determined by the phase transition temperature. It is associated with a reversible transformation from martensite to austenite. The aim of this study was to characterize austenite, martensite and R phase temperatures as well as transition temperature ranges of the commonly used clinical NiTi orthodontic arch wires selected from several manufacturers. Methods Differential scanning calorimetry （DSC） method was used to study the phase transformation temperatures and the phase transition processes of 9 commonly used clinical NiTi alloys （types： 0.40 mm （0.016 inch）, 0.40 mm × 0.56 mm （0.016 inch × 0.022 inch））.Results The austenite finish temperatures （Af） of 0.40 mm Smart, Ormco and 3M NiTi wires were lower than the room temperature, and no phase transformation was detected during oral temperature. Therefore, we predicted that these types of NiTi did not possess shape memory property. For 0.40 mm and 0.40 mm × 0.56 mm Youyan I NiTi wires, no phase transformation was detected during the scanning temperature range, suggesting that these two types of wires did not possess shape memory either. The Af of 0.40 mm × 0.56 mm Smart, L＆H, Youyan II Ni-Ti wires were close to the oral temperature and presented as martensitic-austenitic structures at room temperature, suggesting the NiTi wires listed above have good shape memory effect. Although the 0.40 mm × 0.56 mm Damon CuNiTi wire showed martensitic- austenitic structures at oral temperature, its Af was much higher than the oral temperature. It means that transformation from martensite to austenite for this type of NiTi only finishes when oral temperature is above normal. Conclusion The phase transformation temperatures and transformation behavior varied among different commonly used NiTi orthodontic arch wires, leading to variability in shape memory effect.展开更多
Shape memory alloys (SMA) have been applied to a wide variety of applications in a number of different fields such as aeronautical applications, sensors/actuators, medical sciences as well as orthodontics. It is a hot...Shape memory alloys (SMA) have been applied to a wide variety of applications in a number of different fields such as aeronautical applications, sensors/actuators, medical sciences as well as orthodontics. It is a hot topic to enhance the anti-corrosion ability of orthodontic wires for clinical applications. In this letter, a very nice fractal structure, micro-domains with identical nanometer sized grooves, was ob- tained on the surfaces of the orthodontic wires with an oxygen plasma and acid corrosion. The concave parts of the grooves were dominated by titanium and convex parts were the same as the bulk wires. The micro-nano fractal structure generated a hydrophobic surface with the largest contact angle to water being about 157°. The titanium dominated nanolayer and the hydrophobicity of the surface resulted in jointly the great improvement of the anti-corrosion ability of the orthodontic wires. Because the fractal structures of the wires were formed automatically when they immersed in acidic environment, hence, the self-protection of the oxygen plasma-treated orthodontic wires in acidic environment indicates their potential applications in orthodontics, and should be also inspirable for other applications of SMA materials.展开更多
目的:比较Reciproc Blue R25、S3小旋风(BS+B套装)和ORODEKA plex2.0(06锥度)三种机用镍钛器械预备弯曲根管的根管偏移和中心定位能力。方法:选取30颗模拟离体牙的弯曲树脂根管,随机分为三组,每组10颗。分别用Reciproc Blue R25、S3小...目的:比较Reciproc Blue R25、S3小旋风(BS+B套装)和ORODEKA plex2.0(06锥度)三种机用镍钛器械预备弯曲根管的根管偏移和中心定位能力。方法:选取30颗模拟离体牙的弯曲树脂根管,随机分为三组,每组10颗。分别用Reciproc Blue R25、S3小旋风和ORODEKA plex2.0三种不同的机用镍钛器械采用冠向下法预备根管,使用相机拍摄根管预备前后的根管图像,借助制图软件进行预备前后对比收集数据,评价预备后的根管偏移和中心定位能力。结果:Reciproc Blue R25(组1)的预备时间最短,显著小于S3小旋风(组2)和ORODEKA plex2.0(组3)(P<0.05);在根尖区,Reciproc Blue R25(组1)的根尖偏移大于S3小旋风(组2)和ORODEKA plex2.0(组3)(P<0.05);根管弯曲段ORODEKA plex2(组3)根管中心定位能力优于其余两组(P<0.05);弯曲上段,三组间差异无统计学意义(P>0.05)。结论:三种镍钛器械均能维持根管原始形态,Reciproc Blue R25可有效、快速地预备根管;与Reciproc Blue R25相比,S3小旋风和ORODEKA plex2.0具有更好的根管成形能力,更适合弯曲根管的预备。展开更多
文摘Objective:To study the effect of heat-activated nickel-titanium arch wire for orthodontic treatment on local tissue inflammation and bone destruction.Methods:Patients who received orthodontic treatment with nickel-titanium arch wire in Hancheng People's Hospital between March 2012 and October 2017 were retrospectively studied, and according to the nickel-titanium arch wire materials in history data, the patients were divided into the experimental group who used heat-activated nickel-titanium arch wire and the control group who used common nickel-titanium arch wire. 1 week after treatment, the gingival crevicular fluid was collected to determine the contents of inflammatory cytokines as well as the mRNA expression of osteoblast markers and osteoclast markers.Results: 1 week after treatment, IL-1α, IL-1β, sTREM1 and HMGB1 contents as well as RANKL, 5-LOX, LTB4, TRACP5b and ODF mRNA expression in gingival crevicular fluid of experimental group were significantly lower than those of control group whereas OPG, Wnt3a, Runx2, OC, ALP and OCIF mRNA expression were significantly higher than those of control group.Conclusion: Heat-activated nickel-titanium arch wire for orthodontic treatment can be more effective than common nickel-titanium arch wire to reduce the local tissue inflammation and inhibit the bone destruction.
文摘Background As the only active component in final treatment phase of Tip-Edge Plus technique, the activation of nickel-titanium orthodontic archwires is one of the factors that affect the torque expression. It is necessary to evaluate the mechanical properties of the nickel-titanium wire used in the final treatment phase in simulated oral environments to forecast the treatment outcomes. Methods The mechanical properties of 171 thermal nickel-titanium wires of 0.35 mm （0.014-in） in diameters with different deflection of 40 mm in length were investigated with three-point bending test. The samples were divided into 2 groups： as-received and bended groups. In the bended group, samples were divided into 7 subgroups according to the amounts of deflection and named by the canine angulations （-25~, -19~, -13~, -7~, -1~, ＋5~, ＋11~）. The deflection of wires was made by inserting the wires into the deep tunnel of Tip-Edge Plus brackets positioned in plaster casts with different canine angulations to mimic the use of nickel-titanium wires in the final treatment phase. Immersed the bended group in artificial saliva （pH 6.8） and preserved at 37.0~C. Eight durations of incubation were tested： 1 to 8 weeks. Three analogous samples of each group and subgroups were tested per week. Stiffness （YS：E） and the load-deflection characteristics of unloading plateau section were obtained. Results Significant changes in specific mechanical properties were observed in long-term immersed and large deflected wires compared with as-received groups. Both immersion time and deflection affected the mechanical properties of wires in the simulated oral environment, and the two factors had synergistic effect. In groups -25~, -19~ and -13~, stiffness （YS：E） increased then decreased and average plateau force and ratio of variance decreased then increased correspondingly at specific time. Conclusions In the final treatment phase of Tip-Edge Plus technique, the mechanical properties of nickel-titanium wire are associated with the using time and amounts of deflection and it may affect treatment outcomes. As the main reason for wire deflection, canine crown angulation plays an important role in the wire performance. It may be wise to focus on the canine crown angulations and using time in clinic with Tip-Edge Plus technique and make proper adjustment to help to make sure the treatment outcomes.
文摘Background The shape memory effect of nickel-titanium （NiTi） archwires is largely determined by the phase transition temperature. It is associated with a reversible transformation from martensite to austenite. The aim of this study was to characterize austenite, martensite and R phase temperatures as well as transition temperature ranges of the commonly used clinical NiTi orthodontic arch wires selected from several manufacturers. Methods Differential scanning calorimetry （DSC） method was used to study the phase transformation temperatures and the phase transition processes of 9 commonly used clinical NiTi alloys （types： 0.40 mm （0.016 inch）, 0.40 mm × 0.56 mm （0.016 inch × 0.022 inch））.Results The austenite finish temperatures （Af） of 0.40 mm Smart, Ormco and 3M NiTi wires were lower than the room temperature, and no phase transformation was detected during oral temperature. Therefore, we predicted that these types of NiTi did not possess shape memory property. For 0.40 mm and 0.40 mm × 0.56 mm Youyan I NiTi wires, no phase transformation was detected during the scanning temperature range, suggesting that these two types of wires did not possess shape memory either. The Af of 0.40 mm × 0.56 mm Smart, L＆H, Youyan II Ni-Ti wires were close to the oral temperature and presented as martensitic-austenitic structures at room temperature, suggesting the NiTi wires listed above have good shape memory effect. Although the 0.40 mm × 0.56 mm Damon CuNiTi wire showed martensitic- austenitic structures at oral temperature, its Af was much higher than the oral temperature. It means that transformation from martensite to austenite for this type of NiTi only finishes when oral temperature is above normal. Conclusion The phase transformation temperatures and transformation behavior varied among different commonly used NiTi orthodontic arch wires, leading to variability in shape memory effect.
基金Supported by the National Natural Science Foundation of China (Grant No. 30572067)Ministry of Science and Technology of China
文摘Shape memory alloys (SMA) have been applied to a wide variety of applications in a number of different fields such as aeronautical applications, sensors/actuators, medical sciences as well as orthodontics. It is a hot topic to enhance the anti-corrosion ability of orthodontic wires for clinical applications. In this letter, a very nice fractal structure, micro-domains with identical nanometer sized grooves, was ob- tained on the surfaces of the orthodontic wires with an oxygen plasma and acid corrosion. The concave parts of the grooves were dominated by titanium and convex parts were the same as the bulk wires. The micro-nano fractal structure generated a hydrophobic surface with the largest contact angle to water being about 157°. The titanium dominated nanolayer and the hydrophobicity of the surface resulted in jointly the great improvement of the anti-corrosion ability of the orthodontic wires. Because the fractal structures of the wires were formed automatically when they immersed in acidic environment, hence, the self-protection of the oxygen plasma-treated orthodontic wires in acidic environment indicates their potential applications in orthodontics, and should be also inspirable for other applications of SMA materials.
文摘目的:比较Reciproc Blue R25、S3小旋风(BS+B套装)和ORODEKA plex2.0(06锥度)三种机用镍钛器械预备弯曲根管的根管偏移和中心定位能力。方法:选取30颗模拟离体牙的弯曲树脂根管,随机分为三组,每组10颗。分别用Reciproc Blue R25、S3小旋风和ORODEKA plex2.0三种不同的机用镍钛器械采用冠向下法预备根管,使用相机拍摄根管预备前后的根管图像,借助制图软件进行预备前后对比收集数据,评价预备后的根管偏移和中心定位能力。结果:Reciproc Blue R25(组1)的预备时间最短,显著小于S3小旋风(组2)和ORODEKA plex2.0(组3)(P<0.05);在根尖区,Reciproc Blue R25(组1)的根尖偏移大于S3小旋风(组2)和ORODEKA plex2.0(组3)(P<0.05);根管弯曲段ORODEKA plex2(组3)根管中心定位能力优于其余两组(P<0.05);弯曲上段,三组间差异无统计学意义(P>0.05)。结论:三种镍钛器械均能维持根管原始形态,Reciproc Blue R25可有效、快速地预备根管;与Reciproc Blue R25相比,S3小旋风和ORODEKA plex2.0具有更好的根管成形能力,更适合弯曲根管的预备。
