Seawater typically has a salinity of around 35 g/kg, although lower values are typical near coasts where rivers enter the ocean. Rivers and lakes can have a wide range of salinities, from less than 0.01 g/kg to a few g/kg, although there are many places where higher salinities are found.onceptually the salinity is the quantity of dissolved salt content of the water. Salts are compounds like sodium chloride, magnesium sulfate, potassium nitrate, and sodium bicarbonate which dissolve into ions.
Palatal Expansion. Palatal expansion is a combination of tooth movement and jaw expansion. It works by widening the two halves of the upper jaw, called the palate. The two halves are joined together by a 'suture' in the middle of the roof of the mouth.
The research-supported indications for the use of palatal expanders are limited and clear. Indications for use: Simply put, if the upper jaw is too narrow and is in crossbite with the lower jaw, an expander can make it wider. Expander use that is NOT supported by evidence Expander use not indicated: In cases of severe crowding, the