American Medical Association Family Medical Guide - American Medical Association [791]
During an oral examination, the dentist first carefully inspects your mouth—including the tongue, the roof of the mouth, the insides of the cheeks, and the salivary glands—for signs of any diseases that are not confined to the teeth. For example, gums that are red, puffy, tender, or receding (pulling away from the teeth) indicate periodontal disease (see page 1114). A white discoloration of the inside of the mouth may indicate that you have oral thrush (see page 744), leukoplakia (see page 744), or oral lichen planus (see page 745). The dentist then examines your teeth with a mirror and a needle-shaped probe, looking for color changes that may indicate decay or cracks that may indicate the beginning of a cavity. He or she also examines your fillings to see if any parts have chipped off or if any new cavities are developing around the edges of a filling. If you have bridges or dentures, the dentist will check them for fit and examine their effects on your gums and any remaining teeth.
Why Your Dentist Takes X-Rays
Every year or two, your dentist takes bitewing X-rays (one or two X-rays of each side of your mouth are taken while you bite down on a piece of wing-shaped plastic to hold the X-ray film in place) to check for problems that he or she cannot detect during a visual examination. Every 3 to 5 years, your dentist should take a full set of mouth X-rays or a panoramic X-ray. He or she should also take X-rays of any teeth that have been treated with a root canal (see below) to look for a possible tooth abscess (see right). The dentist may also use X-rays to check the growth of your wisdom teeth or to determine how much bone is supporting your teeth if you have periodontal disease (see page 1114).
Bitewing X-rays
One method of taking X-rays of the teeth uses a small piece of X-ray film that is covered by a protective wing-shaped plastic casing that is gripped firmly between the teeth.
Root Canal
At the core of every healthy tooth is the pulp, tissue that nourishes the tooth and makes it sensitive to heat, cold, pressure, and pain. However, the pulp may become infected or die after tooth decay penetrates it. The pulp may die after a blow to the tooth or, in some cases, for no obvious reason. If the pulp is infected or dead, root canal treatment is performed to save the tooth. Root canal treatment is usually performed by an endodontist (a dentist who specializes in root canal treatment).
A tooth with infected or dead pulp should be treated as soon as possible after it is detected because bacteria from the pulp can seep through the end of the root and cause a tooth abscess (see right). Although infected pulp may cause pain and swelling, it often produces no symptoms. Because a tooth with dead pulp can continue to function efficiently, it will not be removed unless it is badly decayed.
For root canal treatment the endodontist usually numbs the area around the affected tooth with a local anesthetic and places a rubber sheet called a dental dam around the tooth to isolate it from adjacent teeth. He or she then drills through the top of the crown of the tooth and into the pulp chamber. Next, the endodontist cleans out the root canal; disinfects it to kill the bacteria; fills the empty pulp chamber with a soft, rubberlike material to prevent recontamination; and seals the root canal. In some cases the endodontist inserts a metal post above the canal filling to reinforce the tooth. Your regular dentist will then place a crown over the tooth to restore its structure, function, and appearance.
Root canal
When the pulp in a tooth becomes infected, a tooth abscess can form. The tooth must be treated by cleaning out the root canal, destroying any bacteria, filling and sealing the canal, and restoring the crown.
Tooth Abscess
A tooth abscess is a pocket of pus in the tissue around the tip of the root of a tooth. An abscess usually forms when a tooth is decaying, when its pulp is infected or dead, or when the gums have receded