Caries which affected one or more tooth (cavitated non-cavitated lesions), premature loss as result of decay, or surfaces filled in any primary tooth in children aged 71 months or younger refers to Early childhood caries (ECC) (Drury et al., 1999). Serious consequence such as pain, infection, impaired speech, poor height and weight growth development due to unmanaged ECC as well as premature tooth loss (Ayhan et al., 1996 and Low et al., 1999). In spite of these adverse consequences, the prevalence of children diagnosed with ECC is increased (Tinanoff and Reisine, 2009), preventing the initiation and progression of dental decay are important to the oral health and overall health of children. Several elements play a significant role in the development of dental caries, including oral hygiene status, nutrition, medical status and deficiency of essential vitamins and minerals, such as vitamin D.
Several physiologic processes such as bone remodeling and growth development as well as morphogenesis, differentiation, enamel and pulp development are regulated by Vitamin D (Glijer et al., 1985). Calcium and phosphorus levels are maintained by vitamin D; without it lead to decreased intestinal absorption of dietary calcium and phosphorus (Holick, 2007). parathyroid hormone (PTH) levels raised When calcium (Ca++) levels are declined resulting in increasing tubular resorption of Ca++ and inducing the osteoclasts for mobilizing of Ca stores from the bone.
In addition, The kidneys convert 25(OH) D to its active form of vitamin D, 1, 25-dihydroxyvitamin D by induction of PTH (Schroth et al., 2012 and Holick, 2006), it is estimated that 1 billion people at least around worldwide suffering from insufficient or deficiency vitamin D (Holick, 2007). When the level of vitamin D is less than 20 ng per milliliter refers to vitamin D deficiency (Hujoel, 2013). Several causes of vitamin D deficiency, including heritable disorders, acquired disorders and reduced synthesis of vitamin D absorbed through the skin (Holick, 2007) (Schwalfenberg, 2011).Vitamin D deficiency leads to several conditions such as vitamin D resistant rickets, osteoporosis, dental enamel hypoplasia and dental caries.