Effects of frequency of exposure to iron-sucrose on the incidence of dental caries in desalivated rats.

World Health Organization (WHO) estimates that 2.5 billion people have anemia caused by iron deficiency that could be prevented by fortification of food; sugar, for example, has been used successfully as a vehicle for dietary iron fortification. The inclusion of 88 ppm of iron (as FeSO4) co-crystallized with sugar has been shown to reduce the incidence of caries by more than 30% when rats are fed 17 meals daily at hourly intervals. The purpose of the present study was to determine the influence of varying the number of daily exposures to iron on caries in desalivated rats. Four litters of 12 Sprague-Dawley rats were desalivated when aged 25 days and caged in a programmed feeder. All animals received their essential nutrition by gavage and 17 meals of sucrose daily. In Group A, 6 meals contained 88 ppm Fe; in Group B, 3 meals continued iron: Group C had 2 meals, and in Group D, no iron was added. The investigation continued for 3 weeks. Smooth-surface and sulcal (in parentheses) caries scores were: Group A 60.8 (39.4); Group B 72.4 (41.3); Group C 73.1 (41.3), and Group D 92.9 (49.2). Caries scores in all the iron groups were statistically lower than in the control group. Severity scores followed a similar pattern. Thus, as few as 2 daily exposures to iron-sucrose had a significant effect on caries development; therefore the use of iron as a cariostatic agent is worthy of further exploration. The concept that two major public health problems could be alleviated by the addition of iron to sucrose is indeed attractive.