Ettinger R L, Bergman W, Wefel J
Department of Prosthodontics, College of Dentistry, University of Iowa, Iowa City.
Am J Dent. 1994 Feb;7(1):17-21.
This study evaluated the caries preventive effects of high concentrations of fluoride on overdenture abutment teeth. Twenty-four extracted caries-free teeth were randomly selected from a pool of patients aged 50-70 and prepared as for overdenture abutments. The teeth were sectioned mesiodistally into two halves. All surfaces on the teeth were painted with a protective varnish except for a window on the root surface and one on the cut dentin of the occlusal. The 48 root halves were randomly divided into four groups of 12 specimens. Each group received a different 4-minute treatment prior to being placed in a demineralizing solution for 6 hours. The treatment groups were (1) distilled H2O only; (2) 1,000 ppm F-; (3) 5,000 ppm F-; and (4) 10,000 ppm F-. The teeth were cycled for 6 hours in the demineralizing solution and 17 hours in a fluoride-free remineralizing solution for 17 days. Sections were cut at 100 +/- 10 microns through the windows. Standardized photomicrographs were made under polarized light using distilled H2O and quinoline as the imbibing media. Microradiographs were made of the same specimens and these were also photographed at the same magnification. The depths of the lesions were measured from drawings of the lesions projected on a digitizer screen. The amount of demineralization was calculated by subtracting the width of the mineralizing bands from the depth of the lesion. The conclusions were: (1) Lesions on the root surface were much shallower than on the occlusal; (2) A dose response to the fluoride concentration of the topical application was evident.
本研究评估了高浓度氟化物对覆盖义齿基牙的防龋效果。从50 - 70岁患者群体中随机选取24颗无龋的离体牙，按照覆盖义齿基牙的要求进行预备。将牙齿近远中向切成两半。除了牙根表面的一个窗口和咬合面切割牙本质上的一个窗口外，牙齿的所有表面均涂有保护漆。48个牙根半片随机分为四组，每组12个标本。每组在放入脱矿溶液中6小时之前接受不同的4分钟处理。处理组分别为：(1)仅蒸馏水；(2)1000 ppm F-；(3)5000 ppm F-；(4)10000 ppm F-。牙齿在脱矿溶液中循环6小时，在无氟再矿化溶液中循环17小时，持续17天。通过窗口以100±10微米的厚度切片。使用蒸馏水和喹啉作为浸润介质，在偏光下制作标准化显微照片。对相同标本制作显微放射照片，并以相同放大倍数拍摄。根据在数字化仪屏幕上投射的病变图测量病变深度。通过从病变深度中减去矿化带宽度来计算脱矿量。结论为：(1)牙根表面的病变比咬合面的病变浅得多；(2)局部应用氟化物浓度存在剂量反应。
