Mazandaran University of Medical Sciences, Dental Faculty, Dental Sciences Research Center, Orthodontic Department, Sari, Iran.
Mazandaran University of Medical Sciences, Dental Faculty, Dental Sciences Research Center, Orthodontic Department, Sari, Iran.
Int Orthod. 2020 Jun;18(2):349-358. doi: 10.1016/j.ortho.2020.02.003. Epub 2020 Mar 17.
Effects of different oral hygiene controls on force kinetics of memory elastic chains are not assessed adequately or in the case of many oral care products, non-existent. This study assessed these.
This in-vitro study was performed on 647 observations of 132 elastic chains assessed at 5 intervals. In each of the treatments (artificial saliva, fluoride, OralB mouthrinse, whitening OralB mouthrinse, toothpaste, and whitening toothpaste), 11 memory and 11 conventional chains were tested. Chains were stretched for 100%; their initial force was measured (g), and immersed in artificial saliva at 37°C. For treatments other than artificial saliva, the specimens were removed from the saliva twice daily and the main treatment was applied. After washing with distilled water, they were immersed back in artificial saliva. At the days 1st, 7th, 14th, and 28th, their force was re-measured. Data were analysed statistically (α=0.05).
Force degradation of elastic chains was observed in both memory/conventional types (P=0.000) although memory chains showed slightly less declines especially in the beginning days. The interaction of treatment and time was significant (P=0.000) meaning that different treatments caused different rates of force decay, with fluoride having the fastest drop rate followed by whitening toothpaste. However, the difference among 5 intervals of time was not significant (P=0.569). When elastic types were assessed separately, this variable as well became significant (P≤0.002). One-sample t-test showed that all final residual forces (28th day) were either above 150g or at its level.
Chain force degrades over time but stays sufficient for bodily tooth movement after 4 weeks. Memory chains are preferable as they provide greater forces for longer durations. Fluoride mouthwash followed by whitening toothpaste cause the most rapid declines. Both chain types still retained adequate forces after 4 weeks, even after treatment with fluoride or whitening toothpaste.
不同的口腔卫生控制措施对记忆弹性链的力动力学的影响尚未得到充分评估，在许多口腔护理产品的情况下，甚至不存在这种影响。本研究对此进行了评估。
本体外研究共评估了 132 根弹性链的 647 个观察值，在 5 个时间间隔进行评估。在每种处理（人工唾液、氟化物、OralB 漱口水、美白 OralB 漱口水、牙膏和美白牙膏）中，测试了 11 根记忆链和 11 根普通链。将链拉伸 100%；测量其初始力（g），并在 37°C 的人工唾液中浸泡。对于非人工唾液的处理，每天两次将标本从唾液中取出并施加主要处理。用蒸馏水冲洗后，它们再次浸泡在人工唾液中。在第 1、7、14 和 28 天，重新测量它们的力。数据进行统计学分析（α=0.05）。
无论是记忆型/普通型弹性链，都观察到链力降解（P=0.000），尽管记忆链的下降幅度略小，尤其是在最初几天。处理和时间的相互作用具有统计学意义（P=0.000），这意味着不同的处理导致力衰减的速率不同，氟化物的下降速度最快，其次是美白牙膏。然而，5 个时间间隔之间的差异没有统计学意义（P=0.569）。当单独评估弹性类型时，此变量也变得具有统计学意义（P≤0.002）。单样本 t 检验显示，所有最终残余力（第 28 天）均高于 150g 或与其水平相当。
链力随时间而降解，但在 4 周后仍足以维持身体牙齿的运动。记忆链更可取，因为它们能提供更长时间的更大力。氟化物漱口水继美白牙膏后会导致最快的下降。即使经过氟化物或美白牙膏处理，两种链类型在 4 周后仍保留足够的力。
