Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil.
Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil,
Caries Res. 2019;53(5):576-583. doi: 10.1159/000499317. Epub 2019 May 14.
This study evaluated the effect of titanium tetrafluoride (TiF4) varnish on the development of dentin carious lesions. Bovine root dentin samples were treated for 6 h with: (A) 4% TiF4 varnish (2.45% F); (B) 5.42% sodium fluoride (NaF) varnish (2.45% F); (C) 2% chlorhexidine (CHX) gel - positive control; (D) placebo varnish; or (E) untreated - negative control (n = 4 × biological triplicate, n = 12). Treated dentin samples were exposed to human saliva mixed with McBain saliva (1:50) for the first 8 h in 24-well plates. Thereafter, the medium was removed, and McBain saliva containing 0.2% sucrose was applied for 16 h. From days 2 to 5, McBain saliva with sucrose was replaced daily (37°C, 5% CO2). The demineralization was measured using transverse microradiography, while the effect on biofilm was analyzed using viability, extracellular polysaccharide (EPS), and lactic acid production assays. The data were statistically analyzed (p < 0.05). All treatments (fluorides and CHX) significantly reduced the biofilm viability compared to placebo varnish and negative control. However, none of them was able to reduce the colony-forming unit counting for total microorganism, total streptococci, and Streptococcus mutans. NaF significantly reduced the number of Lactobacillus sp. compared to negative control. No effect was seen on lactic acid production neither on EPS synthesis, except that CHX significantly reduced the amount of insoluble EPS. Both fluorides were able to reduce dentin demineralization compared to placebo varnish and negative control; TiF4 had a better effect in reducing mineral loss and lesion depth than NaF. Therefore, TiF4 varnish has the best protective effect on dentin carious lesion formation using this model.
本研究评估了钛四氟化物（TiF4）涂料对牙本质龋损发展的影响。将牛牙本质样本用以下方法处理 6 小时：（A）4%TiF4 涂料（2.45%F）；（B）5.42%氟化钠（NaF）涂料（2.45%F）；（C）2%洗必泰（CHX）凝胶-阳性对照；（D）安慰剂涂料；或（E）未处理-阴性对照（n=4×生物学重复，n=12）。处理后的牙本质样本在 24 孔板中用含有人唾液的 McBain 唾液（1:50）在最初的 8 小时内进行暴露。此后，移去培养基，并将含 0.2%蔗糖的 McBain 唾液应用 16 小时。从第 2 天到第 5 天，每天更换含蔗糖的 McBain 唾液（37°C，5%CO2）。使用横向显微放射摄影术测量脱矿作用，使用生物膜活力、细胞外多糖（EPS）和乳酸生成测定来分析对生物膜的影响。对数据进行了统计学分析（p<0.05）。与安慰剂涂料和阴性对照相比，所有处理（氟化物和 CHX）均显著降低了生物膜活力。然而，它们均未能降低总微生物、总链球菌和变形链球菌的菌落形成单位计数。与阴性对照相比，NaF 显著降低了乳酸菌的数量。除 CHX 显著降低不溶性 EPS 的量外，EPS 合成和乳酸生成均未见影响。两种氟化物均能减少牙本质脱矿作用，与安慰剂涂料和阴性对照相比；TiF4 在减少矿物质损失和病变深度方面的效果优于 NaF。因此，使用该模型，TiF4 涂料对牙本质龋损形成具有最佳的保护作用。
