To understand tooth sensitivity we have to understand the tooth.
The teeth are the hardest substances in the human body. Besides being essential for chewing, the teeth play an important role in speech. Parts of the teeth include:
• Enamel: The hardest, white outer part of the tooth. Enamel is mostly made of calcium phosphate, a rock-hard mineral.
• Dentin: A layer underlying the enamel. Dentin is made of living cells, which secrete a hard mineral substance.
• Pulp: The softer, living inner structure of teeth. Blood vessels and nerves run through the pulp of the teeth.
• Cementum: A layer of connective tissue that binds the roots of the teeth firmly to the gums and jawbone.
• Periodontal ligament: Tissue that helps hold the teeth tightly against the jaw.
A normal adult mouth has 32 teeth, which (except for wisdom teeth) have erupted by about age 13:
• Incisors (8 total): The middlemost four teeth on the upper and lower jaws.
• Canines (4 total): The pointed teeth just outside the incisors.
• Premolars (8 total): Teeth between the canines and molars.
• Molars (8 total): Flat teeth in the rear of the mouth, best at grinding food.
• Wisdom teeth or third molars (4 total): These teeth erupt at around age 18, but are often surgically removed to prevent displacement of other teeth.
The crown of each tooth projects into the mouth. The root of each tooth descends below the gum line, into the jaw.
Sensitivity of the teeth can occur for many reasons. Some of the causes include:
• Teeth grinding and clenching
• Exposed root surfaces due to gum recession or tooth brush abrasion
• Gum Recession
• Tooth cracks or fractures
• Decay, infected pulp
• Tooth trauma, nerve damage
Often times if you solve the cause of a problem you will eliminate the symptoms. Tooth sensitivity caused by grinding and clenching, can often be eliminated by reducing, eliminating or learning to cope with the stresses encountered in one's life. Tooth sensitivity brought about by malocclusion (improper bite) can be reduced in various ways, including: adjusting one's bite, redoing inadequate restorations, correcting asymmetries and poor jaw position using various removable appliances, and sometimes full mouth reconstruction to restore teeth to their proper levels.
Minor amounts of sensitivity can often be controlled with desensitizing toothpastes, fluoride gels or other types of desensitizing agents. However, if the level of discomfort is changing your lifestyle, or is a constant source of distress, you should address this sensitivity more definitively. First, you should see your dentist to determine the cause of your sensitivity (i.e. exposed root areas, teeth grinding, fracture, cavities, etc.). Second, take note of what causes the sensitivity (i.e. hot, cold, air, sweets, etc.), and its duration (does it linger, or does it go away after the stimulus is removed). Often times your dentist can put a layer of bonding over an exposed root, make a night guard (to prevent grinding), or repair a cavity or minor tooth fracture. If the sensitivity still persists, a more involved treatment may be indicated.