Protection of calcium silicate/sodium phosphate/fluoride toothpaste with serum on enamel and dentin erosive wear

Abstract Objective To evaluate the effect of a toothpaste containing calcium silicate/sodium phosphate/fluoride associated or not to the boost serum (BS) against erosive tooth wear (ETW) on enamel and dentin. Methodology Bovine enamel and dentin specimens were subjected to an erosion-abrasion cycling model (1% citric acid - pH 3.6 -2 min / artificial saliva – 60 min, 4×/day, 5 days). Toothbrushing was performed for 15 s (2 min exposed to slurry), 2×/day, with the toothpastes (n=10): control without fluoride (Weleda), Arg/Ca/MFP (Colgate Pro-Relief), Si/PO4/MFP (Regenerate-Unilever), and Si/PO4/MFP/BS (Si/PO4/MFP with dual BS – Advanced Enamel Serum-Unilever). The effect of treatments on the eroded tissues was assessed by surface microhardness in the first day, and surface loss (SL) resulting from ETW was evaluated by profilometry (μm) after three and five days. Additional dentin specimens (n=5/group) were subjected to 20,000 brushing cycles to verify the abrasivity of the toothpastes. Data were subjected to ANOVA and correlation tests (5%). Results For enamel, no difference in microhardness was observed among the treated groups, and similar SL was obtained after 5 days. For dentin, Si/PO4/MFP/BS resulted in higher microhardness values, but none of the groups presented significantly lower SL than the control. There was no significant correlation between SL and abrasiveness. Conclusion The calcium silicate/sodium phosphate toothpaste and serum increased microhardness of eroded dentin, but they did not significantly reduce enamel and dentin loss compared to the non-fluoride control toothpaste. The abrasiveness of the toothpastes could not predict their effect on ETW.

摘要
研究目的：评估含硅酸钙/磷酸钠/氟化物的牙膏，联合或不联合强化血清（boost serum, BS），对牙釉质与牙本质上的侵蚀性牙磨损（erosive tooth wear, ETW）的防护效果。
研究方法：选取牛牙釉质及牙本质标本，构建侵蚀-磨耗循环模型（1%柠檬酸，pH 3.6，暴露2分钟/人工唾液浸泡60分钟，每日4次，持续5天）。每日以对应牙膏进行2次刷牙操作，每次15秒（牙膏糊剂与标本接触2分钟），共设4组（每组n=10）：无氟对照牙膏（Weleda）、精氨酸/钙/单氟磷酸钠（monofluorophosphate, MFP）组（Colgate Pro-Relief）、硅酸钙/磷酸钠/单氟磷酸钠（MFP）组（Regenerate-联合利华）、硅酸钙/磷酸钠/单氟磷酸钠/BS组（即搭载双效强化血清的硅酸钙/磷酸钠/单氟磷酸钠配方，Advanced Enamel Serum-联合利华）。分别于第1日通过表面显微硬度检测评估各处理对侵蚀组织的作用效果，于第3日和第5日通过轮廓测厚法（μm）测定ETW导致的表面缺损（surface loss, SL）。另取每组n=5的牙本质标本进行20000次刷牙循环，以验证各牙膏的磨蚀性。数据采用方差分析（ANOVA）及相关性检验，显著性水平设定为5%。
研究结果：牙釉质各组间显微硬度无显著差异，第5日的表面缺损量亦无统计学差异。牙本质组中，硅酸钙/磷酸钠/单氟磷酸钠/BS组的显微硬度值更高，但所有实验组的表面缺损量均未显著低于无氟对照组。表面缺损量与牙膏磨蚀性无显著相关性。
研究结论：含硅酸钙/磷酸钠的牙膏联合强化血清可提升侵蚀后牙本质的显微硬度，但与无氟对照牙膏相比，未显著减少牙釉质与牙本质的侵蚀缺损量。牙膏的磨蚀性无法预测其对侵蚀性牙磨损的干预效果。