In some cases, teeth do not erupt properly through the jawbone and gum tissue, into the mouth. Maxillary canines (upper eye teeth) are the most commonly impacted, after wisdom teeth. Impacted teeth may cause problems including bone loss, root resorption, or formation of cysts or tumours. Your Orthodontist and Oral & Maxillofacial Surgeon can work together with a combination of braces and minor surgical procedures, including tooth exposure & bonding of an orthodontic bracket, to bring the tooth properly in alignment with the other teeth. Surgical procedure can be completed while awake, or with a variety of anesthesia options.
What are Impacted Canines and Impacted Teeth?
An impacted tooth is one that does not properly erupt into the mouth. The most commonly impacted teeth are wisdom teeth, followed by the maxillary canines (upper eye teeth). The canines are important teeth as they frame your smile, and are also important for chewing. However, any tooth could potentially become impacted, for numerous reasons.
Impacted canines occur in 2% of the population, affecting twice as many females as males, and twice as many in the top jaw as the bottom jaw. This can sometimes occur on both the right and left. The majority of impacted canines are located on the roof of the mouth.
There are many reasons that teeth may become impacted. In some cases there may not be enough room in the jaw for them to fit. In other cases, they cannot follow the normal track along adjacent teeth to erupt into proper position. Other theories suggest a genetic component may be a contributing factor in impacted teeth, and may be associated with other dental abnormalities.
Diagnosis of Impacted Canines and Teeth
How do we find out if a canine or other tooth is impacted? And how do we find out where it is?
The first method is easy – observation and palpation. Adult teeth should erupt at certain ages; if they’re missing, then there may be a problem. In addition, the angulations and positions of adjacent teeth may give a clue as to the position of the missing tooth. Careful examination of the area, along with feeling along the gum tissue, may give a hint as to the missing tooth’s position.
X-rays are typically the next step in gathering information. There are several types of x-rays that are typically taken including panorex, periapicals and occlusals. Multiple x-rays are commonly required, and are important for determining if a tooth is impacted, the tooth’s position in relation to the jaw and adjacent teeth, the effect on adjacent teeth and structures, and for planning purposes.
In some cases, a CT scan may be ordered and will provide detailed 3-dimensional information about the impacted tooth’s position.
Problems from Impacted Canines and Teeth
Impacted canines and teeth that are left in place may go throughout the patient’s lifetime with no untoward effects. However, close monitoring and at regular dental care intervals is recommended. On the other hand, these impacted teeth may have several untoward effects and consequences.
The simplest problem is that a tooth will be missing from the smile. Although sometimes a baby tooth will be retained in that position, it will never have the proper shape and size that an adult tooth will have. In the worst-case scenario, there will be a gap that is visible beside the rest of the teeth.
Impacted teeth may also cause damage to adjacent teeth, known as resorption. In resorption, the impacted tooth “eats away” at the a portion of the healthy tooth. Many times this is unrestorable, and in rare cases may actually cause loss of the tooth. If resorption does not occur, adjacent teeth may be pushed out of their normal positions from pressure of the impacted tooth, causing mal-alignment.
Pathology can sometimes develop around an impacted tooth. Pathology usually represents an abnormal growth of tissue around the tooth, typically in the form of a cyst or tumour. While there are many different variations and types of cysts and tumours, treatment at a minimum would require removal of the lesion and possibly removal of the impacted tooth. Worst case scenarios would result in loss of adjacent teeth, and possibly need for further surgical treatment to ensure that the lesion does not recur.
Treatment of Impacted Canines and Teeth, including Exposure and Orthodontic Bonding
Treatment for impacted canines can vary.
In some cases, removing the baby canine can create enough space for the adult tooth to drop into position. This would usually be done around 10-13 years of age. However, this does not guarantee correction or elimination of the problem. The tooth should be monitored and, if not corrected or improved after a year, additional treatment should be undertaken.
Surgical treatments exist to help bring an impacted canine or tooth into proper position. Selection of the type of procedure depends on which tooth is impacted, the degree of impaction, and the position of the tooth within the jaw bone.
- Gingivectomy (Open Exposure) can be used, where overlying gum tissue is simply removed to allow the tooth to erupt naturally, or to allow the orthodontist to bond an attachment to it directly.
- Apically positioned flaps are used to expose the tooth through the gum tissue, but also to create a healthy band of gum tissue around the tooth.
Exposure and bonding involves uncovering the impacted tooth and bonding an orthodontic attachment to it, then replacing the gum tissue over the tooth. The attachment is connected to a gold chain that is used to apply gentle traction to coax the tooth into position.
Extractions are sometimes considered with some impacted teeth. However, it is seldom a good idea to extract an impacted canine. Not only are the canines important aesthetically in the smile, but they are also important in a functional bite. The rare situation where canine extraction might be considered include: ankylosis, where the tooth is “stuck” and will not come into position; it is undergoing resorption which indicates an inflammatory reaction is compromising the tooth; there are pathologic changes like cysts or tumours, as mentioned above; the impaction is severe, and is jeopardizing adjacent teeth; or if the patient does not want to pursue orthodontic treatment.