冷光美白技术与夜间活髓牙脱色技术协同漂白四环素牙的临床研究

目的评价冷光美白技术与夜间活髓牙脱色技术（NGVB）协同治疗四环素牙的临床效果。方法将90名四环素牙患者根据四环素牙着色的轻、中、重度随机分入治疗组、对照1组、对照2组，其中治疗组30名患者472颗四环素牙，采用冷光美白技术与NGVB对四环素牙进行漂白；对照1组30名患者466颗四环素牙，采用冷光美白技术对四环素牙进行漂白；对照2组30名患者469颗四环素牙，采用NGVB对四环素牙进行漂白。在治疗结束时、治疗结束半年及1年时采用Vitalescence美学修复比色板对四环素牙进行比色，记录牙齿漂白前后的色阶变化及疗程，计算治疗有效率，并评价疗效稳定性。结果1）3组患者轻度四环素牙治疗后均有较好的牙色改善，美白有效率均为100%；治疗组与对照2组中、重度四环素牙治疗后牙色改善及美白有效率好于对照1组（P<0.05），治疗组与对照2组间无统计学差异（P>0.05），但治疗组轻、中、重度四环素牙的治疗疗程较对照2组分别缩短了43%、46%和49%。2）3组患者轻、中、重度四环素牙的美白疗效依次减弱（P<0.05）。3）对照1组半年后及1年后的美白有效率与治疗结束时有统计学差异（P<0.01），而治疗组和对照2组半年后及1年后的美白有效率与治疗结束时无统计学差异（P>0.05）。结论冷光美白技术与NGVB协同治疗轻、中度四环素牙可以在较短的疗程内取得令人满意的美白效果，并提高美白效果的长期稳定性。

Clinical survey of a combined in-office cold Hght bleaching and ulghtguard vital bleaching system for tetracycline stained teeth

OBJECTIVE: To evaluate the clinical efficacy of a combined in-office cold light bleaching and night-guard vital bleaching (NGVB) system for treating tetracycline stained teeth (TST). METHODS: 90 patients with light, medium and heavy TST were randomly and evenly divided into 3 groups. 30 patients with 472 TST from the treatment group were treated with in-office cold light bleaching and NGVB, 30 patients with 466 TST from the control group 1 were treated with in-office cold light bleaching and 30 patients with 469 TST from control group 2 were treated with NGVB. At the time of treatment completion, after half a year and after one year, Vitalescence esthetic restorative masters shade guide was used to record the change of color. Bleaching efficacy and course of treatment were calculated, and lightening stability were evaluated. RESULTS: 1) Three groups had satisfied lightening efficacy for light TST with 100% bleaching efficacy. The overall efficacy of treatment group and control group 2 were superior to the in-office cold light bleaching system (P < 0.05). Though there was no significant lightening efficacy difference between the treatment group and control group 2 (P > 0.05), the periods of treatment of the treatment group for light, medium and heavy TST were shortened by 43%, 46% and 49%, respectively, compared to the control group 2. 2) All three groups' treatment efficacy for light, medium and heavy TST became weaker progressively (P < 0.05). 3) For the treatment efficacy between the time of treatment completion and after half a year and one year, there was significant statistical difference (P < 0.01) for the control group 1, while there was no significant difference for both the treatment group and the control group 2 (P > 0.05). Both treatment group and control group 2 had better performance in treatment stability than control group 1. CONCLUSION: In treating the light and medium tetracycline stained teeth, the combined in-office cold light bleaching and NGVB system can achieve a more satisfied whitening result in much shorter period, and significantly enhance the long term whitening stability.