Though it may occur at any age, including in children, it is most often observed in women between 30 and 60 years of age. The highest prevalence from one study was found in the elderly members of the community.Those that already have an autoimmune disease are at greater risk of developing Hashimotos as the diseases generally coexist with each other. Common diseases seen coexisting with Hashimotos include celiac disease, multiple sclerosis, type 1 diabetes, vitiligo, and rheumatoid arthritis.Congenital hypothyroidism affects 1 in 3500-4000 newborns at birth and is a version of intellectual disability that can be treated if caught early, but can be hard to diagnose given that symptoms are minimal at a young age. Congenital hypothyroidism is generally caused by defects of the thyroid gland, but for most cases in Europe, Asia, and Africa, the iodine intake can cause hypothyroidism in newborns. Geographic influence of dietary trends
Diets consisting of low or high iodine intake determine a populations risk of developing thyroid-related disorders. It is more common in regions of high iodine dietary intake, and among people who are genetically susceptible. Geography plays a large role in which regions have access to diets with low or high iodine. Iodine levels in both water and salt should be heavily monitored in order to protect at-risk populations from developing hypothyroidism.Geographic trends of hypothyroidism vary across the world as different places have different ways of defining disease and reporting cases.
Dentin dysplasia (DD) is a rare genetic developmental disorder affecting dentine production of the teeth, commonly exhibiting an autosomal dominant inheritance that causes malformation of the root. It affects both primary and permanent dentitions in approximately 1 in every 100,000 patients. It is characterized by presence of normal enamel but atypical dentin with abnormal pulpal morphology. Witkop in 1972 classified DD into two types which are Type I (DD-1) is the radicular type, and type II (DD-2) is the coronal type. DD-1 has been further divided into 4 different subtypes (DD-1a,1b,1c,1d) based on the radiographic features. Signs and symptoms
Clinically the teeth look normal in colour and morphologic appearance; however, they are commonly very mobile and exfoliated prematurely.Both primary and permanent dentitions can be affected by either type I or type II dentin dysplasia. However, deciduous teeth affected by type II dentin dysplasia have a characteristic blue-amber discolouration, whilst the other dentition appears normal. Causes
The mutation in collagen type 1 (COL1 A1, COL1 A2) causes DI-1. It is similar to the systemic condition dental features known as osteogenesis imperfect. DI-2, DI-3 and DD-2 share the same genetic mutation of dentin sialophosphoprotein, that is located on chromosome 4. They are autosomal-dominant diseases with complete penetrance and variable expressivity. Due to the same genetic mutation, these diseases would often result in overlapping clinical and radiographic features. Therefore, prevailing theories suggests that DI-2, DI-3 and DD-2 are categorized as a single disease entity with variable severity of expression. However, the causes of DD-1 have yet to be theorized.