Effect of At-Home Bleaching on Oxygen Saturation Levels in the Dental Pulp of Maxillary Central Incisors

Abstract The present study assessed oxygen saturation (SaO2) levels before, during, and after at-home bleaching treatment in the pulps of healthy maxillary central incisors. SaO2 levels were measured in 136 healthy maxillary central incisors using a pulse oximeter. The bleaching protocol consisted of 10% carbamide peroxide gel placed in individual trays and used for four hours daily for 14 days. SaO2 levels were assessed before bleaching (T0), immediately after the first session (T1), on the 7th day of treatment (T2), on the 15th day (the day following the last session) (T3), and 30 days after completion of the bleaching protocol (T4). Data were statistically analyzed using generalized estimating equations (GEE), Student’s t test (p<0.05) and Pearson’s correlation. Mean pulp SaO2 levels were 85.1% at T0, 84.9% at T1, 84.7% at T2, 84.3% at T3, and 85.0% at T4. Gradual reductions in SaO2 levels were observed, with significant differences (p<0.001) during the course of home bleaching treatment. However, 30 days after the end of the bleaching protocol, SaO2 levels returned to baseline levels. Home bleaching caused a reversible transient decrease in SaO2 levels in the pulps.

摘要 本研究评估了健康上颌中切牙牙髓在家庭漂白治疗前、治疗过程中及治疗后的血氧饱和度（oxygen saturation, SaO2）水平。研究纳入136颗健康上颌中切牙，采用脉搏血氧仪（pulse oximeter）检测其牙髓血氧饱和度水平。漂白方案为将10%过氧化脲凝胶（carbamide peroxide gel）置于个体化托盘，每日佩戴4小时，持续14天。分别于以下时间点检测血氧饱和度：漂白前（T0）、首次治疗即刻（T1）、治疗第7天（T2）、第15天（即末次治疗次日，T3）以及漂白方案完成后30天（T4）。采用广义估计方程（generalized estimating equations, GEE）、t检验（Student’s t test，p<0.05）及皮尔逊相关分析（Pearson’s correlation）对数据进行统计学分析。结果显示，T0时牙髓血氧饱和度均值为85.1%，T1为84.9%，T2为84.7%，T3为84.3%，T4为85.0%。家庭漂白治疗期间，血氧饱和度水平呈渐进性降低，治疗全程组间差异具有统计学意义（p<0.001）。但在漂白方案结束后30天，血氧饱和度水平恢复至基线水平。本研究表明，家庭漂白可导致牙髓血氧饱和度出现可逆性短暂下降。