Читать книгу Orthodontic Treatment of Impacted Teeth - Adrian Becker - Страница 21

Let us now look at the consequences of the inevitable time lapse between the performance of a surgical procedure to remove the cause of an impaction and the full eruption of the impacted tooth into the vacated space in the dental arch. The extent of this time‐span is linked to several factors, specifically the initial distance between the tooth and the occlusal plane, the stage of development of the particular tooth, the age of the patient and the manner in which hard and soft tissue may be laid down in the healing wound. There are consequences to this time period, which need to be addressed. Local changes in the erupted dentition, such as space loss and tipping of the adjacent erupted teeth, may occur as a result of the break in integrity of the dental arch caused by the surgical procedure. The surgical intervention is no less likely to elicit the drifting of neighbouring teeth than is any other factor that may be caused by loss of dental tissue and interproximal contacts.

If an odontome or supernumerary tooth creates an obstacle to an unerupted permanent tooth, the result may be substantial vertical (and sometimes mesial, distal, buccal or lingual) displacement of the permanent tooth. In such a case, the ideal treatment would be to remove the obstructing body in order to leave the deciduous teeth intact, since the deciduous teeth would function to maintain arch integrity during the time lapse needed for the permanent tooth to erupt normally. However, in order to gain access to perform the necessary surgery, it is usually necessary to extract one or more deciduous teeth. This brings to the forefront the importance of interim space maintenance, particularly in the posterior area, during the lengthy time needed to allow for the long distance that a displaced permanent tooth may have to travel before it erupts into the mouth. Advance orthodontic planning is called for, preferably before or immediately subsequent to the surgical procedure. The interim space‐holding device should be retained until full eruption of the permanent tooth has occurred.

The impaction of teeth is often associated with the lack of available space in the immediate area. This is frequently due to the drifting of adjacent teeth, as well as to crowding of the dentition in general. In these circumstances, the spontaneous eruption of an impacted tooth is unlikely to occur unless adequate or, preferably, excess space is available. It would be better to delay the excision of the associated pathological entity and permit this corrective treatment to be attempted, until the root development of the unerupted tooth is adequate to bring about the desired eruption. However, the surgeon may not give consideration to the orthodontic aspect and will probably insist on removing most forms of pathology as soon as a tentative diagnosis is reached, in order to obtain examinable biopsy material for the establishment of a definitive diagnosis. Nevertheless, the entirely benign nature of odontomes and supernumerary teeth causes these obstructions to be considered exceptions to this rule and the timing of their removal may be considered in a more leisurely fashion.