目的：评价45S5型生物活性玻璃粉末缓解活髓牙预备后敏感的临床疗效。方法：按照临床试验纳入标准和排除标准招募受试者，纳入活髓牙需行全冠修复患者18例，共31颗牙齿。采用自身前后对照、单盲的研究方法，先后涂布安慰剂（氧化锌粉末）和45S5型生物活性玻璃脱敏剂于受试牙上，并在基线时和应用安慰剂及生物活性玻璃粉末后，分别采用压力敏感探针法和冷空气喷吹法测量牙齿敏感程度，同时记录患者牙齿敏感的Tactile值、患者主观视觉模拟评分量表（visual analogue scale，VAS）数值和术者客观Schiff评分。结果：基线时和应用安慰剂及生物活性玻璃后测量到的Tactile值分别为（29.03±9.44） g、（29.68±9.48） g和（44.19±11.19） g，冷空气刺激VAS值分别为（50.79±22.92） mm、（46.63±22.06） mm和（30.90±20.30） mm，术者Schiff评分分别为2.13±0.67、1.97±0.66和1.42±0.56。统计分析结果表明，应用生物活性玻璃粉末后的Tactile值、冷空气刺激VAS值、术者Schiff评分与基线时和应用安慰剂后差异均有统计学意义（P＜0.05），而基线时和应用安慰剂后Tactile值、冷空气刺激VAS值、术者Schiff评分差异无统计学意义（P＞0.05），Schiff评分的差异与性别、牙位、是否二次备牙相关。结论：45S5型生物活性玻璃粉末对于活髓牙预备后的牙齿敏感有缓解作用。

Objective： To evaluate the efficacy of the 45S5 bioactive glass on the reduction of hypersensitivity of teeth prepared for full coverage crowns. Methods: In the study, 31 prepared abutment teeth with vital pulp from 18 patients satisfied the inclusion criteria and exclusion criteria. The patients were informed consent and recruited into the study. This was a before and after self-control, single blind clinical trial. The severity of tooth hypersensitivity at baseline was evaluated, after application of the placebo, which was the powder of zinc oxide, and after application of the 45S5 bioactive glass on the same tooth. Tooth hypersensitivity was evaluated by Yeaple probe and visual analogue scale (VAS) when the tooth was stimulated by a fixed value of mechanical pressure and a blast of cold air respectively. And the dentist gave the subjective score, and the Schiff score at the same time. The three methods of measurement were repeated at baseline, after application of placebo and after application of the powder of 45S5 bioactive glass. Student’s t test and nonparametric test were used for statistical analysis. Results: The indexes measured at baseline, after the application of the placebo and after the application of the 45S5 bioactive glass were as follows, respectively: Tactile value (29.03±9.44) g, (29.68±9.48) g and (44.19±11.19) g, VAS value (50.79±22.92) mm, (46.63±22.06) mm and (30.90±20.30) mm, Schiff score 2.13±0.67, 1.97±0.66 and 1.42±0.56. After the application of bioactive glass, the values of Tactile, the VAS, and the Schiff score were statistically different from those at baseline or after application of the placebo (P＜0.05). The data measured at baseline and after application of the placebo were of no statistical difference (P＞0.05). Statistical differences between the Schiff scores of the groups were associated with gender, tooth position, primary or secondary tooth preparation. Conclusion: Results of the clinical trial showed that the powders of 45S5 bioactive glass were significantly effective on reducing the hypersensitivity of teeth with vital pulp after the full crown preparation.