Salivary profile of children with erosive tooth wear: a transversal study

Abstract The aim of the present transversal study was to evaluate the clinical and biochemical salivary parameters of children with and without erosive tooth wear (ETW). The study population was children aged 4 to 9 years. A trained and calibrated examiner (kappa value for intraexaminer reliability = 0.89) classified the children into ETW (n = 24) and control groups (n = 24), and applied the O’Brien index. The salivary flow rate was initially evaluated by stimulated sialometry (paraffin chewing). Afterwards, the collected saliva was submitted to biochemical analyses of pH, uric acid, total buffering capacity, ferric-reducing antioxidant power, reduced glutathione, calcium, and phosphorus. Among the ETW children, 20 (83%) had dental lesions restricted to enamel, and 4 (17%) presented lesions affecting both enamel and dentin. A statistically significant difference between the groups was obtained only for the pH values (t-test; p = 0.004), with averages of 7.31 and 7.56 for the control and the ETW groups, respectively. Considering the parameters evaluated in general, it is suggested that the salivary profile of children with ETW does not differ considerably from that of children without ETW. However, the pH mean value seems to be slightly higher in ETW children, but is still within the normal physiological range.

摘要 本横断面研究旨在评估伴与不伴牙侵蚀症（erosive tooth wear, ETW）儿童的临床与生化唾液学参数。研究对象为4~9岁儿童。一名经过培训且完成校准的检查者（组内信度Kappa值为0.89）采用O’Brien指数，将受试者分为ETW组（n=24）与对照组（n=24）。
唾液流速初始通过刺激性唾液流率测定（石蜡咀嚼法）进行评估。随后，对采集的唾液样本开展多项生化分析，包括pH值、尿酸、总缓冲容量、铁还原抗氧化能力、还原型谷胱甘肽、钙及磷含量。
在ETW组儿童中，20例（83%）的牙病变仅累及牙釉质，4例（17%）的病变同时累及牙釉质与牙本质。两组间仅在pH值上存在统计学显著差异（t检验，p=0.004），对照组与ETW组的平均pH值分别为7.31与7.56。综合评估所有检测参数后，提示伴ETW儿童的唾液特征与无该病症儿童并无显著差异。不过，ETW组儿童的平均pH值略高，但仍处于正常生理范围内。