The problem posed to the yeast manufacturer, however, is not as simple as just adding air during the fermentation process. If the concentration of sugar in the fermentation growth media is greater than a very small amount, the yeast will produce some alcohol even if the supply of oxygen is adequate or even in abundance. This problem can be solved by adding the sugar solution slowly to the yeast throughout the fermentation process.
Human teeth are made up of four different types of tissue: pulp, dentin, enamel, and cementum. The pulp is the innermost portion of the tooth and consists of connective tissue, nerves, and blood vessels, which nourish the tooth.
Dental sealants are used to protect the chewing surfaces of back teeth from decay. They are acrylic-like substances which create a barrier against the bacteria which are always in the mouth and always depositing acid excretions on the teeth and gums. Sealants bond to the tooth enamel and cover all the tiny fissures and pits where bacteria would otherwise settle and thrive.