Department of General Dentistry, National Clinical Research Center for Oral Diseases, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Peking University School and Hospital of Stomatology, Beijing, China.
University of Rochester Eastman Institute for Oral Health, 625 Elmwood Ave, Rochester, NY, 14620, USA.
BMC Oral Health. 2021 Nov 30;21(1):610. doi: 10.1186/s12903-021-01977-3.
Many studies have demonstrated efficacy of casein phosphopeptide (CPP) containing products for dentin tubule occlusion for treatment of dentin sensitivity, but their effectiveness under dynamic erosive challenges remains to be elucidated. The purpose of the present study was to investigate the effectiveness of a desensitizing dentifrice containing CPP in occluding dentin tubules and resisting erosive challenges in comparison to that containing polyvinyl methyl ether/maleic acid (PVM/MA) copolymers.
A total of 33 dentin discs were prepared from coronal sections of human third molars and divided into 3 groups: a toothpaste containing CPP; a toothpaste containing PVM/MA and submicron silica; and a regular toothpaste (Controls). A soft-bristle toothbrush was used to brush the dentin discs with the dentifrices for 45 strokes in 30 s at a force of approximately 200 g. The brushing cycle was repeated after immersion of the dentin discs in artificial saliva overnight. The dentin discs were then challenged in orange juice for 10 min in an incubator rocking at 120 rpm. Three fields were randomly selected on each dentin disk surface to assess dentin tubule occlusions after each brushing cycle and after orange juice challenge with a 3D laser scanning microscope. Specimen cross sections were examined with a scanning electron microscope equipped with energy dispersive spectroscopy (SEM/EDS).
After the first and second cycles of brushing, dentin tubules were occluded on average by 56.3% and 85.7% in CPP group, 66.2% and 88.1% in PVM/MA group, and 0.0 and 13.0% in the controls, respectively. There were no statistically significant differences in dentin tubule occlusions between the CPP and PVM/MA groups after two cycles of brushing (p>0.05). After dynamic erosive challenges with orange juice, 20.3% of the dentin tubules in the CPP group, 79.1% in the PVM/MA group and none in the control remained occluded (P<0.05). SEM/EDS imaging showed that dentin tubules were blocked with plugs containing dentifrice substances in CPP and PVM/MA groups after treatments, but none in the controls.
Desensitizing dentifrices containing CPP or PVM/MA could effectively occlude dentin tubules after two cycles of brushing. PVM/MA in combination with submicron silicon dioxide exhibited stronger resistance to dynamic erosive challenges by acidic beverages. Inorganic fillers that can enter dentin tubules and resist erosive challenges may be key for desensitizing dentifrices.
许多研究已经证明含有酪蛋白磷酸肽（CPP）的产品在治疗牙本质敏感症时对牙本质小管闭塞的功效，但它们在动态侵蚀挑战下的效果仍有待阐明。本研究的目的是比较含有 CPP 的脱敏牙膏和含有聚维酮甲基醚/马来酸（PVM/MA）共聚物的脱敏牙膏在封闭牙本质小管和抵抗侵蚀挑战方面的有效性。
从人类第三磨牙的冠状部分制备了总共 33 个牙本质盘，并将其分为 3 组：含有 CPP 的牙膏；含有 PVM/MA 和亚微米二氧化硅的牙膏；和普通牙膏（对照组）。用软毛牙刷以大约 200g 的力在 30s 内用牙刷牙膏进行 45 次刷洗。在人工唾液中浸泡过夜后，重复刷牙周期。然后将牙本质盘在孵育器中以 120rpm 的速度在橙汁中孵育 10min。使用三维激光扫描显微镜在每个牙本质盘表面的三个随机区域评估每次刷牙周期和橙汁挑战后的牙本质小管闭塞情况。使用配备能量色散光谱仪（SEM/EDS）的扫描电子显微镜检查标本横截面。
在第一和第二刷牙周期后，CPP 组的牙本质小管平均闭塞 56.3%和 85.7%，PVM/MA 组为 66.2%和 88.1%，对照组为 0.0%和 13.0%。在两次刷牙周期后，CPP 组和 PVM/MA 组之间的牙本质小管闭塞没有统计学差异（p>0.05）。用橙汁进行动态侵蚀挑战后，CPP 组有 20.3%的牙本质小管、PVM/MA 组有 79.1%的牙本质小管和对照组没有牙本质小管闭塞（P<0.05）。SEM/EDS 成像显示，在处理后 CPP 和 PVM/MA 组的牙本质小管中被含有牙膏物质的塞子阻塞，但对照组中没有。
含有 CPP 或 PVM/MA 的脱敏牙膏在两次刷牙周期后可有效封闭牙本质小管。PVM/MA 与亚微米二氧化硅结合具有更强的抵抗酸性饮料动态侵蚀挑战的能力。能够进入牙本质小管并抵抗侵蚀挑战的无机填料可能是脱敏牙膏的关键。
