A person’s third molars are their wisdom teeth. These teeth come in behind the 2nd molars (if there is room for them and they are aligned properly), usually during a person’s late teens or early twenties. Typically a person will have four wisdom teeth: upper left, upper right, lower left, and lower right.
What are “impacted wisdom teeth” ?
In dental terminology an “impacted” tooth refers to a tooth that has failed to emerge fully into its expected position. This failure to erupt properly might occur because there is not enough room in the person’s jaw to accommodate the tooth, or because the angulation of the tooth is improper.
The most common type of impacted wisdom tooth is one that is impacted mesially. The other types of impactions, in order of frequency of occurrence, are the vertical, horizontal, and distal types.
Why do impacted teeth need to be removed ?
Wisdom teeth, either partially or fully erupted, are often very difficult to clean. (The term “erupted” used here means that the wisdom tooth has, at least to some degree, penetrated through the gums.)
Any location in the mouth where plaque is allowed to accumulate and persist, such as around a partially erupted wisdom tooth, a person will run the risk of developing dental problems such as tooth decay (“cavities”), periodontal disease (“gum disease”), or recurring infections. Typically it is the partially erupted impacted wisdom tooth that is more unpredictable or troublesome for a person than an impacted wisdom tooth that has never penetrated through the gum tissue.
One condition that can occur, often repeatedly, when wisdom teeth are impacted is pericoronitis. The term pericoronitis refers to an infection located in the tissues that surround a tooth that has not fully emerged through the gums and on into its proper position (this type of tooth positioning would be termed “partially erupted”).
Dental plaque will accumulate in this hidden space and, unfortunately, there is no way for a person to effectively clean it out. The signs of pericoronitis are tenderness and swelling in the gum tissue surrounding a wisdom tooth.