Localization And Clinical Research Of The Impacted Teeth Of Anterior Maxilla

An impacted tooth is a condition in which a tooth is embedded in the alveolus so that its eruption is prevented or the tooth is locked in position by bone or by the adjacent teeth. Impaction of teeth, particularly that of permanent teeth of anterior maxilla, is not a very rare dental anomaly. They result in the following sequelae, such as dentigerous cyst formation, external root resorption of the adjacent teeth, loss of arch length, etc. The treatment is usually a challenge to orthodontists.The experimental group was gathered from the department of orthodontics of stomatological college which belongs to the Forth Military Medical University and consisted of randomly selected children with natural dentitions who required treatment for one or both impacted teeth. The incidence, etiology and treatment of the impacted maxillary central incisor and canines have been analyzed . The useful value of three-dimensional computed tomographyh and multiplanar reconstruction techniques for impacted teeth in bone has been studied. Another purpose of this study is to explore a reliable method of diagnosing the position of an impacted maxillary canine on the basis of a panoramic radiograph. Results1 .By imposing vertical restricton, the bucco-palatal position of those caninesthat overlapped the middle or coronal zones of the adjacent teeth could be accuracy achieved. But the canine overlapped the apical zone of the adjacent incisors couldn't be diagnosed from panoramic radiography solely.2. The reconstruction image can clearly show the dental surface image including crown and root of teeth in three-dimensional way, labial or palatal position, eruption way and relation with adjacent teeth of maxilla.3. This study shows that impaction of maxillary central incisors occurs more frequently in females than in males. The main cause is abnormity of teeth in the shape and position. Traumatic injury to the certain region is an importent aetiological factor of impaction. The clinical approach and solution is surgical-orthodontic treatment, removal of impacted teeth or transplantation.4. The mean age of this subgroup of maxillary canines impacted is 13.8 years old(range 10-27 years).Most of them located in the buccal direction. Crowding is the main cause of impaction. The interceptive treatment, no treatment, extracted impacted teeth, transplantation or surgical-orthodontic treatment can be applied. There exist some esthetic and periodontal differences in these solutions. Conclusion1. It may be concluded that, provided both vertical restriction and a magnification index are used, the panoramic radiograph is a reliable indicator for determining the bucco-palatal position of impacted maxillary canines.2. The three-dimensional computed tomographyh and multiplanar reconstrution(MPR) technique are of the techniques to display three-dimensional surface configuration of teeth and to locate its position precisely. The technique can be applied to examine impacted teeth in bone for surgery orthodontic practice.3. Most of the impacted maxillary canines and central incisors can be moved to the correct position by effective treatment. In order to achieve a good result, the management in each case should depend upon many factors, including:(l)Pay attention to the age of the patient and devlopmental stage of the dentition and the position of the unerupted tooth. (2) The impacted tooth interfering by the soft tissue or younger developmental stage of the dentitions should be led to erupt by itself.(3)Applying correct treatment, such as full flap closure ,closed-eruption techniques, the proper direction of traction, controlling the strength of traction and anchorage,etc. (4)Removal of unerupted teeth with malformation which have no treatment value.