Saxton C A, Harrap G J, Lloyd A M
J Clin Periodontol. 1986 Apr;13(4):301-6. doi: 10.1111/j.1600-051x.1986.tb02226.x.
Zinc salts have previously been shown to possess antiplaque activity in solution but this activity has as yet not been reported for dentifrices. The purpose of the present investigation was to establish the effect of dentifrices containing zinc citrate (ZCT) on plaque growth and on the concentration of zinc in saliva and plaque. Plaque growth inhibition was studied over periods of time approximating to intervals for normal oral hygiene procedures. Zinc in saliva and plaque was measured by atomic absorption spectroscopy. Elevated zinc levels in saliva were observed for 3-4 h after brushing with the zinc citrate dentifrice. Similarly, raised levels of zinc were encountered in plaque 1 h following contact with a slurry of a dentifrice containing ZCT. Increased concentrations of zinc were observed in plaque fluid and plaque residue. The plaque growth data from 88 participants in 5 studies revealed that plaque regrowth over 16 h or 22 h was reduced by dentifrices containing 0.5% ZCT, compared to placebo dentifrices. Dentifrices which contained 0.5% ZCT or 0.4% stannous fluoride, had similar inhibitory effects on plaque. Further analysis of the data showed that subjects with high rates of plaque growth benefited more from the zinc dentifrices than those with low rates of plaque growth. It is suggested that the effect on plaque was related to zinc concentration in the dentifrice rather than total dose applied, and that the main effect of zinc was to inhibit the extension of existing plaque.
锌盐此前已被证明在溶液中具有抗牙菌斑活性，但这种活性尚未见诸牙膏的相关报道。本研究的目的是确定含柠檬酸锌（ZCT）的牙膏对牙菌斑生长以及唾液和牙菌斑中锌浓度的影响。在接近正常口腔卫生程序间隔的时间段内研究牙菌斑生长抑制情况。通过原子吸收光谱法测量唾液和牙菌斑中的锌含量。使用含柠檬酸锌的牙膏刷牙后3至4小时，观察到唾液中锌水平升高。同样，在与含ZCT牙膏的糊剂接触1小时后，牙菌斑中锌水平也会升高。在菌斑液和菌斑残渣中观察到锌浓度增加。来自5项研究中88名参与者的牙菌斑生长数据显示，与安慰剂牙膏相比，含0.5%ZCT的牙膏可减少16小时或22小时内的牙菌斑再生长。含0.5%ZCT或0.4%氟化亚锡的牙膏对牙菌斑具有相似的抑制作用。对数据的进一步分析表明，牙菌斑生长速率高的受试者比牙菌斑生长速率低的受试者从含锌牙膏中获益更多。研究表明，对牙菌斑的影响与牙膏中的锌浓度有关，而非所施用的总剂量，并且锌的主要作用是抑制现有牙菌斑的扩展。
