This vitro study aimed to evaluate the effects of 45S5 bioactive glass (BAG) and Er:YAG laser as desensitization treatments on the microtensile bond strength (MTBS) of fluorosed teeth. The 120 noncarious fluorosis were to obtain superficial dentin, being classified into four groups according to the Thylstrup and Fejerskov Index (TFI). Specimens from each group were randomly divided into five subgroups. After fluorosed teeth hypersensitivity models were established, the following pretreatments were applied on dentine surface: Subgroup 1: deionized water (Control); Subgroup 2: BAG; Subgroup 3: Er:YAG laser; Subgroup 4: BAG + Er:YAG laser, and Subgroup 5: Er:YAG laser + BAG. One sample was randomly selected from each subgroup for scanning electron microscope (SEM). The remaining samples were bonded with composite resin by Adper Single Bond 2 adhesive. Then water bath at 37°C for 24 hr. After 5,000 thermocycling, MTBS was tested and fracture mode was analyzed. The difference of MTBS between BAG group and Control group was found statistically significant (p < .05) in fluorosis. The Er:YAG laser + BAG group showed lowest MTBS values in fluorosis. In conclusion, the pretreatment of BAG might be beneficial to the adhesive of fluorosed teeth. Er:YAG laser desensitization alone or using BAG first and then Er:YAG laser desensitization might not affect the adhesive of fluorosed teeth, while Er:YAG laser desensitization followed by the pretreatment of BAG would be not conducive to the adhesive of fluorosed teeth.

中文翻译：

---

45S5生物活性玻璃和Er:YAG激光对含氟牙齿微拉伸粘结强度的影响

本体外研究旨在评估 45S5 生物活性玻璃 (BAG) 和 Er:YAG 激光作为脱敏治疗对含氟牙齿微拉伸粘合强度 (MTBS) 的影响。120 例非龋性氟斑牙获得浅表牙本质，根据 Thylstrup 和 Fejerskov 指数（TFI）分为四组。每组的标本被随机分为五个亚组。在建立含氟牙齿超敏反应模型后，对牙本质表面进行以下预处理： 亚组 1：去离子水（对照）；亚组 2：袋；子组 3：Er:YAG 激光；第 4 组：BAG + Er:YAG 激光，第 5 组：Er:YAG 激光 + BAG。从每个亚组中随机选择一个样品用于扫描电子显微镜（SEM）。其余样品通过 Adper Single Bond 2 粘合剂与复合树脂粘合。然后在 37°C 水浴 24 小时。经过 5,000 次热循环后，测试了 MTBS 并分析了断裂模式。BAG组与对照组的MTBS差异有统计学意义（p  < .05) 氟中毒。Er:YAG 激光 + BAG 组在氟中毒中的 MTBS 值最低。总之，BAG的预处理可能有利于氟牙的粘接。单独使用Er:YAG激光脱敏或先BAG后Er:YAG激光脱敏可能不会影响氟牙的粘接，而Er:YAG激光脱敏后BAG预处理不利于氟牙的粘接。