Notaroberto Daniela Ferreira de Carvalho, Martins Mariana Martins E, Goldner Maria Teresa de Andrade, Mendes Alvaro de Moraes, Quintão Cátia Cardoso Abdo
Universidade do Estado do Rio de Janeiro, Programa de Pós-graduação em Odontologia, Departamento de Odontologia Preventiva e Comunitária (Rio de Janeiro/RJ, Brazil).
Universidade Federal Fluminense, Faculdade de Odontologia, Disciplina de Ortodontia (Niterói/RJ, Brazil).
Dental Press J Orthod. 2018 Nov-Dec;23(6):42-47. doi: 10.1590/2177-6709.23.6.042-047.oar.
This clinical study was conducted in order to evaluate force decay over time of latex and non-latex orthodontic intraoral elastics.
Patients (n = 15) were evaluated using latex and non-latex elastics in the periods of : 0, 1, 3, 12 and 24 hours. The rubber bands were transferred to the testing machine (EMIC DL-500 MF), and force values were recorded after stretching the elastic to a length of 25mm. Paired t test was applied and analysis of variance (ANOVA) was used to evaluate the variation of force generated. LSD (Fisher's least significant difference) post-hoc test was thus employed.
As regards the initial forces (zero time), the values of force for non-latex elastic were slightly higher than for the latex elastic. In the subsequent times, the forces generated by the latex elastic showed higher values. Regarding the material degradation, at the end of 24 hours the highest percentage was observed for non-latex elastic.
The latex elastics had a more stable behavior during the studied period, compared with non-latex.
开展这项临床研究以评估乳胶和非乳胶正畸口内弹力线随时间的力衰减情况。
对15名患者在0、1、3、12和24小时期间使用乳胶和非乳胶弹力线进行评估。将橡皮筋转移至测试机（EMIC DL - 500 MF），在将弹力线拉伸至25毫米长度后记录力值。应用配对t检验并使用方差分析（ANOVA）来评估产生的力的变化情况。因此采用了LSD（Fisher最小显著差异）事后检验。
关于初始力（零时间），非乳胶弹力线的力值略高于乳胶弹力线。在随后的时间里，乳胶弹力线产生的力显示出更高的值。关于材料降解，在24小时结束时，观察到非乳胶弹力线的降解百分比最高。
与非乳胶弹力线相比，在研究期间乳胶弹力线表现出更稳定的特性。
