Department of Restorative Dentistry, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia.
Department of Cariology, Operative Dentistry and Dental Public Health, Indiana University School of Dentistry, Indianapolis, IN, USA.
J Dent. 2018 Sep;76:89-92. doi: 10.1016/j.jdent.2018.06.018. Epub 2018 Jun 22.
To investigate the interplay among brushing frequency, dentifrice slurry abrasivity, and fluoride content on the surface loss (SL) of incipient enamel caries-like lesions.
Lesions were created in 96 bovine enamel specimens (5 × 5 mm) using methylcellulose acid gel. Specimens were randomly allocated to 12 groups (n = 8), resulting from the association of three experimental factors: (1) slurry abrasive level [low: REA = 4/RDA = 69 and high: REA = 7/RDA = 208], (2) fluoride concentration [275 and 1250 ppm F as NaF], and (3) brushing frequency [1, 2 and 3× daily]. Specimens were kept in artificial saliva in between brushings and overnight. SL was determined by optical profilometry after lesion creation, 1, 3, 5, and 7 days. Data was analyzed with repeated measures ANOVA and Tukey's tests (α = 0.05).
High abrasive slurry caused significantly more SL than low with 275 ppm (p < 0.001) but not with 1250 ppm fluoride (p = 0.34). Fluoride at 275 ppm had significantly more SL than 1250 ppm with high abrasive slurry after 7 days (p = 0.008). Brushing 1×/day had significantly less SL than 3×/day after 7 days with high abrasive slurry (p = 0.016), especially in the 275 ppm fluoride groups.
Higher fluoride concentration increased protection against the deleterious effect of high abrasive slurry. SL was higher if brushing was performed more than twice daily especially in low fluoride groups.
Highly abrasive toothpaste formulations might cause more surface wear to incipient caries lesions, especially at higher brushing frequencies. Increasing the fluoride content may be beneficial at these circumstances.
研究刷牙频率、牙膏浆的研磨性和氟化物含量在釉质早期龋损表面损失（SL）中的相互作用。
使用甲基纤维素酸凝胶在 96 个牛牙釉质标本（5×5mm）上制备病变。标本随机分为 12 组（n=8），这是三个实验因素的组合：（1）浆体研磨性水平[低：REA=4/RDA=69 和高：REA=7/RDA=208]，（2）氟化物浓度[275 和 1250ppm F 作为 NaF]，（3）刷牙频率[1、2 和 3×每日]。在刷牙和过夜之间，标本保留在人工唾液中。在病变形成后、第 1、3、5 和 7 天，通过光学轮廓仪测定 SL。采用重复测量方差分析和 Tukey 检验（α=0.05）对数据进行分析。
高研磨性浆体导致 SL 明显高于低研磨性浆体（p<0.001），但与 1250ppm 氟化物（p=0.34）无关。高研磨性浆体下，7 天后 275ppm 氟化物的 SL 明显高于 1250ppm 氟化物（p=0.008）。高研磨性浆体下，每天刷牙 1 次的 SL 明显低于每天刷牙 3 次的 SL（p=0.016），尤其是在 275ppm 氟化物组中。
较高的氟化物浓度增加了对高研磨性浆体有害影响的保护作用。如果每天刷牙超过两次，SL 会更高，尤其是在低氟化物组中。
高研磨性牙膏配方可能会对釉质早期龋损造成更大的表面磨损，尤其是在更高的刷牙频率下。在这种情况下，增加氟化物含量可能是有益的。
