Alweneen Athar, Alqahtani Nasser
Department of Pediatric Dentistry and Orthodontics, College of Dentistry, King Saud University, 11545, Riyadh, Saudi Arabia.
Saudi Dent J. 2025 Jun 11;37(4-6):18. doi: 10.1007/s44445-025-00026-x.
Although guidelines recommend removing aligners before eating, many patients wear them while consuming food or beverages. Understanding the response of a material to high temperatures is crucial for predicting treatment outcomes. This study aimed to assess the effects of elevated beverage temperatures on the physical and mechanical properties of Invisalign clear aligners. Sixty Invisalign aligner specimens were thermocycled and divided into four groups. The specimens in the first and second groups were immersed in coffee and tea at 57 °C, respectively, whereas the third and fourth groups consisted of raw and thermocycled specimens, respectively. Each specimen from group 1 and 2 was immersed in each solution and subsequently in artificial saliva to simulate an intermittent drinking process, which was repeated 200 times, with each immersion lasting 2 s. The elastic moduli and hardnesses of the materials were measured and compared with those of the raw and thermocycled specimens. Statistically significant differences were observed in mean hardness and elastic modulus values (p < 0.0001 and p = 0.025, respectively). The mean hardness of the raw specimens was significantly higher than those of the other three groups (p < 0.0001 each), and the elastic modulus was lower than that of the coffee group (p = 0.018) but not statistically different from those of the thermocycling and tea groups (p = 0.413 and p = 0.309, respectively). Thermocycling and exposure to beverages at 57 °C significantly decreased the hardness of Invisalign clear aligners. The coffee-exposed group exhibited an increased elastic modulus, indicating greater rigidity. Investigating the effects of increased temperature on thermoplastic materials is crucial to ensuring the durability and safety of orthodontic treatment, which directly impacts patient care.
尽管指南建议进食前取下矫治器，但许多患者在食用食物或饮料时仍佩戴着。了解材料对高温的反应对于预测治疗效果至关重要。本研究旨在评估饮料温度升高对隐适美透明矫治器物理和机械性能的影响。将60个隐适美矫治器样本进行热循环处理并分为四组。第一组和第二组样本分别浸泡在57°C的咖啡和茶中，而第三组和第四组分别由未处理样本和经过热循环处理的样本组成。将第一组和第二组的每个样本浸入每种溶液中，随后浸入人工唾液中以模拟间歇饮用过程，重复200次，每次浸泡持续2秒。测量材料的弹性模量和硬度，并与未处理样本和经过热循环处理的样本进行比较。观察到平均硬度和弹性模量值存在统计学显著差异（分别为p < 0.0001和p = 0.025）。未处理样本的平均硬度显著高于其他三组（每组p < 0.0001），弹性模量低于咖啡组（p = 0.018），但与热循环组和茶组无统计学差异（分别为p = 0.413和p = 0.309）。热循环处理以及在57°C下接触饮料显著降低了隐适美透明矫治器的硬度。咖啡暴露组的弹性模量增加，表明刚性更大。研究温度升高对热塑性材料的影响对于确保正畸治疗的耐久性和安全性至关重要，这直接影响患者护理。
