Salivary glands play an important role in lubricating the mouth and aiding in digestion. They secrete saliva which contains amylase that breaks down carbs, and salivary lipase which breaks down fats.
Gums are the tissue in the mouth that surround the teeth. They provide a protective sealant around teeth to prevent tooth decay from oral bacteria.
Teeth play an important role in the mastication, chewing, of food. This aids in digestions as smaller pieces of food are easier to digest. They also contain nerve fibers which is why damage to teeth can be extremely painful.
Xerostomia, also known as dry mouth, is a lack of saliva production. This is commonly a side effect of many medications which prevent the autonomic nervous system from activating salivation. Lack of saliva can lead to damaging buildup of harmful oral bacteria.
Periodontal disease is severe inflammation of the gums surround the teeth. This can lead to a variety of negative symptoms such as gum recession, tooth loss, buildup of harmful oral bacteria, and halitosis (bad breath).
A cavity is a hole in the tooth that is produced by bacteria. A diet rich in sugars can lead to a buildup of harmful oral bacteria which release acid that demineralizes the tooth.
Xerostomia -> Salivary Gland
As many cases of xerostomia are caused by medications, the best treatment is to stop the offending medication. If this isn't possible, then the sugar alcohol, xylitol, can be used to stimulate salivation.
Periodontal Disease -> Gum
As periodontal disease is most likely to occur in patients with poor oral hygiene, correcting this problem with proper routine deep cleaning dental visits and proper brushing/flossing habits are the best treatment.
Cavity -> Tooth
Cavities in teeth need to have all damaged tooth tissue removed and remaining hole sealed to prevent further tooth loss. Common fillings include composite resin and silver amalgam, or historically gold.