Abstract：
OBJECTIVE: To evaluate the effect of four different photoactivation protocols (according to \"photoactivated faces\" - mesial/distal, cervical/incisal or center - and \"photoactivation time\" - 6-3 s) of a high-power photo activator (Valo Cordless®-Ultradent) on the shear bond strength (SBS) between metal brackets and dental enamel and on the degree of conversion (DC) of an orthodontic resin.
METHODS: 40 bovine incisor crowns were randomly assigned to 4 groups (n = 10). The brackets were bonded with Transbond XT® resin using 4 protocols according to the \"photoactivation protocol\" factor (which was subdivided into photoactivated faces and photoactivation time): V3C = 3 s + center; V6C = 6 s + center; V3M3D = 3 s on mesial + 3 s on distal; V3C3I = 3 s on cervical + 3 s on incisal. All the samples were stored for 4 months (water,37ºC) and then subjected to a SBS test (100KgF,1 mm/min). 40 resin discs were made to evaluate the monomer degree of conversion. Data from the SBS and DC were assessed by One-way ANOVA and Tukey\'s test (5%). Bond failures were analyzed according to the Adhesive Remnant Index (ARI) and evaluated by the Kruskal-Wallis test (5%).
RESULTS: There was a statistically significant difference (p = 0.008) in the One-way ANOVA result for SBS values between all groups, but the protocols showed statistically similar results (p ≥ 0.05-Tukey\'s tests) concerning the photoactivated faces (V6C, V3M3D and V3C3I) and photoactivation time (V3C and V6C) factors individually. There was no statistically significant difference (p ≥ 0.05) in the One-way ANOVA result for DC values.
CONCLUSIONS: The SBS and DC values will vary depending on the protocol applied.
CONCLUSIONS: It is possible to maintain the bracket fixation quality with the use of a high-power LED photo activator associated with a shorter photoactivation time. However, it is assumed that not all types of protocols that might be applied will provide quality bonding, such as V3C, V3M3D and V3C3I, which may - depending on the SBS and DC values - affect the final treatment time, due to brackets debonding, or increase of possibility of damage to dental enamel during bracket removal. Clinical studies are suggested to confirm the hypotheses of this research.
METHODS: 40 bovine incisor crowns were randomly assigned to 4 groups (n = 10). The brackets were bonded with Transbond XT® resin using 4 protocols according to the \"photoactivation protocol\" factor (which was subdivided into photoactivated faces and photoactivation time): V3C = 3 s + center; V6C = 6 s + center; V3M3D = 3 s on mesial + 3 s on distal; V3C3I = 3 s on cervical + 3 s on incisal. All the samples were stored for 4 months (water,37ºC) and then subjected to a SBS test (100KgF,1 mm/min). 40 resin discs were made to evaluate the monomer degree of conversion. Data from the SBS and DC were assessed by One-way ANOVA and Tukey\'s test (5%). Bond failures were analyzed according to the Adhesive Remnant Index (ARI) and evaluated by the Kruskal-Wallis test (5%).
RESULTS: There was a statistically significant difference (p = 0.008) in the One-way ANOVA result for SBS values between all groups, but the protocols showed statistically similar results (p ≥ 0.05-Tukey\'s tests) concerning the photoactivated faces (V6C, V3M3D and V3C3I) and photoactivation time (V3C and V6C) factors individually. There was no statistically significant difference (p ≥ 0.05) in the One-way ANOVA result for DC values.
CONCLUSIONS: The SBS and DC values will vary depending on the protocol applied.
CONCLUSIONS: It is possible to maintain the bracket fixation quality with the use of a high-power LED photo activator associated with a shorter photoactivation time. However, it is assumed that not all types of protocols that might be applied will provide quality bonding, such as V3C, V3M3D and V3C3I, which may - depending on the SBS and DC values - affect the final treatment time, due to brackets debonding, or increase of possibility of damage to dental enamel during bracket removal. Clinical studies are suggested to confirm the hypotheses of this research.
摘要：
目的：评估四种不同光活化方案的效果（根据“光活化面”-中/远端，高倍光激活剂(ValoCordless®-Ultradent)的宫颈/切口或中心-和“光活化时间”-6-3s)对金属托槽和牙釉质之间的剪切粘结强度(SBS)和正畸树脂的转化程度(DC)的影响。
方法：将40个牛切牙冠随机分为4组（n=10）。根据“光活化方案”因子（分为光活化面和光活化时间），使用4种方案将支架与TransbondXT®树脂粘合：V3C=3s中心；V6C=6s中心；V3M3D=3s在远端内侧3s；V3C3I=3s在宫颈上+3s切缘3s。所有样品均保存4个月(水，37ºC)，然后进行SBS测试(100KgF，1mm/min)。制备40个树脂圆盘以评价单体转化度。通过单因素方差分析和Tukey检验(5%)评估来自SBS和DC的数据。根据粘合剂残留指数(ARI)分析粘结失效,并通过Kruskal-Wallis测试(5%)进行评估。
结果：所有组之间的SBS值的单向ANOVA结果具有统计学上的显着差异（p=0.008），但协议显示了关于光活化面的统计学相似结果(p≥0.05-Tukey\'s测试)(V6C，V3M3D和V3C3I）和光活化时间（V3C和V6C）因素分别存在。DC值的单向ANOVA结果没有统计学上的显着差异（p≥0.05）。
结论：SBS和DC值将根据所应用的方案而变化。
结论：使用与较短的光活化时间相关的大功率LED光活化剂可以保持支架的固定质量。然而,假设并非所有可能应用的协议类型都将提供质量绑定，比如V3C,V3M3D和V3C3I，这可能-取决于SBS和DC值-影响最终治疗时间，由于支架脱粘，或增加牙釉质在托架移除过程中损坏的可能性。建议进行临床研究以证实该研究的假设。
方法：将40个牛切牙冠随机分为4组（n=10）。根据“光活化方案”因子（分为光活化面和光活化时间），使用4种方案将支架与TransbondXT®树脂粘合：V3C=3s中心；V6C=6s中心；V3M3D=3s在远端内侧3s；V3C3I=3s在宫颈上+3s切缘3s。所有样品均保存4个月(水，37ºC)，然后进行SBS测试(100KgF，1mm/min)。制备40个树脂圆盘以评价单体转化度。通过单因素方差分析和Tukey检验(5%)评估来自SBS和DC的数据。根据粘合剂残留指数(ARI)分析粘结失效,并通过Kruskal-Wallis测试(5%)进行评估。
结果：所有组之间的SBS值的单向ANOVA结果具有统计学上的显着差异（p=0.008），但协议显示了关于光活化面的统计学相似结果(p≥0.05-Tukey\'s测试)(V6C，V3M3D和V3C3I）和光活化时间（V3C和V6C）因素分别存在。DC值的单向ANOVA结果没有统计学上的显着差异（p≥0.05）。
结论：SBS和DC值将根据所应用的方案而变化。
结论：使用与较短的光活化时间相关的大功率LED光活化剂可以保持支架的固定质量。然而,假设并非所有可能应用的协议类型都将提供质量绑定，比如V3C,V3M3D和V3C3I，这可能-取决于SBS和DC值-影响最终治疗时间，由于支架脱粘，或增加牙釉质在托架移除过程中损坏的可能性。建议进行临床研究以证实该研究的假设。
