Effects of Zinc Deficiency on Dental Caries in Rats

Abstract

The effects of graded levels of dietary zinc on the development and mineralization of teeth and bones and on the susceptibility of teeth to dental caries were studied in young growing rats. Thirty-six weanling male Sprague-Dawley rats were randomly assigned to four dietary treatments: 1) zinc-deficient, less than 1 ppm; 2) 12 ppm zinc; 3) 36 ppm zinc, and 4) 108 ppm zinc. For treatments 2, 3 and 4, rats were pair-fed the quantity of feed consumed by their individual counterparts fed the zinc-deficient diet. After 4 weeks of treatment, growth retardation along with other clinical zinc deficiency signs were observed in rats fed the zinc-deficient diet. The zinc levels in bones and teeth of zinc-deficient rats were lower than those for rats fed supplemental zinc. Increased dietary zinc resulted in greater levels of zinc in bones and teeth, but the levels of calcium decreased. Greater incidences of enamel lesions in mandibular molars were observed in rats fed the zinc-deficient diet than in rats pair-fed zinc-supplemented diets. Furthermore, the effect of zinc deficiency on dental caries of young rats was predominantly at the smooth surfaces of the molars. Dietary zinc may be an important trace mineral in the process of post-eruptive mineralization of the enamel and may reduce the susceptibility of teeth to caries.

The Study of Carious Teeth by Laser-Induced Breakdown Spectroscopy

“…First, calcium diminishes under caries. Secondly, zinc is subject to two parallel effects: the fi rst one is its loss under the effect of caries, and the second is replacing calcium in the hydroxyapatite [12,27]. Moreover, it has been shown that after eruption, zinc concentrations apparently increase more on the teeth surface [14], which may validate our interpretation.…”

Effect of Chlorhexidine-Fluoride Applications Without and With Sr and Zn on Caries, Plaque, and Gingiva in Rats

“…The synergistic enamel-protective action by Sr and F has been discussed previously (Dedhiya et al, 1974). Fang et al (1980) concluded in their rat study that dietary Zn may be an important trace metal in the process of post-eruptive mineralization of the enamel and that it may reduce the susceptibility of teeth to caries. Although our results on caries reduction did not offer much support to this concept, the plaque-reducing tendency by Zn in our study was somewhat promising for future attempts to improve the effect of the CXF solution against gingivitis.…”

“…Conversely, Zn deficiency in growing rats has been shown to result in elevated caries incidence (Fang et al, 1980), suggesting a post-eruptive need of Zn for enamel maturation. Zinc chloride with the anti-microbial agent, cetylpyridinium chloride (CPC), has been shown to reduce calculus formation in dogs more than did the CPC alone, while plaque was reduced by both treatments (Ritchey et al, 1982).…”

Zinc balance is critical for NFI‐C mediated regulation of odontoblast differentiation

“…In addition, zinc insufficiency has been related to defective collagen synthesis and delayed skeletal maturation [Prasad and Bose, 1975;Agren, 1991]. Furthermore, zinc deficiency has been linked to oral disease, such as human taste impairments, parakeratosis in the black plaque buccal epithelium [Chen et al, 1975], and susceptibility to dental caries [Hambidge et al, 1972;Fang et al, 1980]. However, the role of zinc in the odontoblast differentiation and dentin mineralization has not yet been clearly defined.…”