EC Dental Science

Impacted central incisors demonstrate one of the biggest fears the patients and their families may face. They appear at a young age and highly affect the appearance and phonetics of the patient. Incisors affect the whole appearance of the face as they are at the center of the face. This fact makes the eyes immediately notice any asymmetry that may appear in them. The central incisors also support the lips, giving the face a normal appearance. They affect phonetics as they play a significant role in pronouncing many letters and words. The impaction of central incisors is less common than the congenitally missing lateral incisors, and the incidence of their impaction is far lower than those of the canines. The impaction of incisors occurs only by an incidence of 0.06 - 1%, however; they are still considered to have a much higher impact on patients’ psychology and appearance.

Other than the standard tooth impaction, an additional feature that was added to the impacted incisors made it much harder to be tracked and made the whole process difficult; this feature is “Dilaceration”. Dilaceration is a dental deformity characterized by an angulation between the crown and root, causing non-eruption of the incisor. When there is dilaceration in the tooth, the traction process should be more cautious as any uncontrolled applied forces may cause severe damage to the tooth and may even cause resorption and loss of the impacted tooth. “If impacted teeth have dilacerated roots, patients should be told the possibility of root resorption”. This statement was written in an American Journal declaring how hard the traction is and how to directly inform the patient about the possibility of resorption whenever there is a dilaceration. The degree of dilaceration can determine the degree of difficulty of orthodontic traction.

The etiology becomes confined to one of two causes when there are dilacerations in impacted teeth. The first cause is trauma during tooth germ formation; this is the most common cause. When damage occurs to the primary tooth, it causes defects in the tooth buds of the permanent successor causing deviation in the deposition of cementum which eventually causes abnormality in the root formation. The other reason is idiopathic and only occurs due to ectopic tooth germ developments. All of the mentioned theories are discussed in detail in the dental book: Dental Traumatology which assesses the possibilities and reasons.

When treating impacted central incisors, one tough challenge is the midline. The midline is highly affected in impaction cases. This effect is due to the natural drifting of the teeth at this stage. The drifting of the teeth may cause partial or total loss of the space needed for the impacted tooth. In this case, clinicians usually have to provide this space back before the orthodontic traction process to allow enough area for the tooth to land after the eruption.

Before any orthodontic application, a treatment strategy should be available. Clinicians should prepare for all the steps ahead; they have to choose the technique of exposing the impacted tooth and calculate the forces that will be applied to the tooth for traction to avoid any injury to the impacted tooth during its traction. The treatment requires a neat collaboration between surgical and orthodontic procedures to provide representative results to the clinician and the patient.

Keywords: Orthodontic Considerations; Maxillary Central Incisor; Dilaceration

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