wisdom teethImpacted Wisdom Teeth
An impacted tooth is a tooth that fails to fully emerge through the gums. The precise reasons why an individual`s wisdom teeth need to be extracted should be explained to them by their dentist, after an examination which almost certainly will need to include x-rays. Impacted wisdom teeth are very common. They are often painless and cause no apparent trouble. Most people have four wisdom teeth, one in each corner of the mouth- two on top, two on bottom. Wisdom teeth are also known as third molars are the last teeth to erupt. Wisdom teeth are the last of your teeth to come in, or erupt through the gums. Wisdom teeth are an example of a vestigial structure. They are generally thought to be called wisdom teeth because they appear so late- much later than the other teeth, at an age where people are supposedly wiser than as a child, when the other teeth erupt. An impacted tooth remains embedded in soft gingiva (gum) tissue or bone beyond its normal eruption time. The cause may be overcrowding, often because the jaw is too small to fit the third set of molars. Wisdom teeth are the last permanent teeth to develop. They appear in the mouth  between the ages of 18-24 years and may develop in the jaw but never erupt or appear in the mouth. 
Mesioangular impaction is the most common form, and means the tooth is angled forward, towards the front of the mouth. Wisdom teeth do not always cause problems but typical problems associated with partially erupted wisdom teeth are frequent swelling and tenderness, constant pain, limited mouth opening and bad breath or an unpleasant taste in the mouth. A condition that often occurs when wisdom teeth are impacted is pericoronitis. The term pericoronitis specifically refers to an infection located in the tissues that surround a tooth that has not fully emerged through the gums and into its proper position. When a wisdom tooth is partially erupted, food and bacteria collect under the gum causing a local infection. This may result in bad breath, pain, swelling and trismus (inability to open the mouth fully). Impacted wisdom teeth fall into one of several categories. Vertical impaction occurs when the formed tooth does not erupt fully through the gumline. It is generally suggested that teeth that remain completely buried or un-erupted in a normal position are unlikely to cause any harm to the patient.