A-Over time, even with good teeth cleaning, plaque and tartar can attach to the teeth similar to lime build-up in a kettle or iron. The saliva fluids in our mouths contain calcium and bacteria.-According to oral hygiene standards, it is recommended that patients visit the dentist every six months for an oral health check-up, to discuss any medical changes such as new medications that can affect oral wellbeing, and to have teeth cleaned with scaling and polishing where necessary.
Industrial smog occurs when the smoke and sulfur dioxide produced from burning coal merges with fog and creates a yellowish-brown-colored haze close to ground level. Photoch â¦ emical smog forms as the result of increased usage of all fossil fuels, including gasoline and the burning of trees and organic waste.
Other emissions that affect human health and create smog include ozone and carbon monoxide. (See Reference 1) The good news is that despite the increase of vehicles on the road, air quality today is actually better than it was in the 1970s, thanks to the 1970 Clean Air Act.