This study presents a retrospective analysis of patients treated for impacted unerupted teeth by a combined surgical and orthodontic approach. Teeth which were impacted included maxillary and mandibular canines, maxillary central incisors, and maxillary and mandibular bicuspids. Many treatment alternatives are available for these cases, but the one with the best long-term prognosis appears to be the surgical exposure and direct orthodontic traction rather than auto-transplantation, or excision of mucosa and packing of the defect.

Impacted teeth are common findings among patients visiting the dental clinic. It could be defined as a tooth which is prevented from erupting into position because of malposition, lackof space, or other impediments. A substantial number of these teeth are indicated for surgical removal since they may be the cause of infection, pain or cyst formation.¹

A number of studies concerning the incidence of impactions were reported since 1930.²³ They showed that third molar is the most common tooth to be impacted with an incidence of 18%. This is followed in frequency by the maxillary cuspid with an incidence of 0.9 - 1.8%, with the upper and lower bicuspid and central incisor next in frequency.

Patients with impacted teeth continue to form a significant proportion of those attending the clinic of the College of Dentistry at King Saud University seeking advise and treatment. Some present with a relatively difficult problem, and careful assessment and selection of the most suitable method of treatment is not always easy.

Third molars are always removed surgically with few exceptions, where they are transplanted in place of badly decayed first molars with poor prognosis. The cases of impacted canine and other teeth always presented a different problem. Surgical exposure involving creating a window in the mucosal covering with or without subsequent orthodontic treatment, allowing the teeth to erupt utilizing it in active eruption, transplantation and surgical removal and prosthodontic replacement were the treatment options available.

The purpose of this paper was to present a relatively large number of impacted teeth treated by surgical exposure and orthodontic traction to bring them into occlusion and evaluate the result of such method in treating impacted teeth.

In this study, 49 patients (44 females and 5 males) in the age-group 12-24 years (mean age: 1 7 years) were involved. Table 1 shows 21 patients with bilaterally impacted canine, 18 in the upper jaw and 3 in the lower jaw; 7 had unilaterally impacted canine in the upper jaw and 5 in the lower jaw. In 6 cases, the upper central incisors were all bilaterally impacted except for one case having an impacted upper right central. The premolar teeth were impacted in 4 patients, one patient had an upper and lower first premolar bilaterally impacted, and an impacted lower left second premolar. One patient had an impacted second molar and 5 had multiple impacted teeth including canine upper and lower, premolars upper and lower, and central incisor (Table 1).

All patients were examined jointly by an oral surgeon and an orthodontist to assess the possibility of other treatment modalities. The clinical examination involved evaluation of the available space in the dental arch, and the need to preserve the impacted tooth. Cleidocranial dysplasia was excluded in patients with multiple impactions.

Oral hygiene motivation and cooperation of the patients were considered as important factors in patient selection. In adult patients, the need to wear an orthodontic appliance and their attitude toward these appliances were explained and discussed with them.

Radiographic examination included an orthopantomograph, periapical and occlusal intra- oral films [Figs. 1a and b]. The position of the impacted teeth in the arch was assessed carefully as well as their relation to the neighboring teeth. The position of the apex in relation to some important anatomical structures, e.g. the inferior dental canal, mental foramen, and the maxillary sinus was also evaluated. With impacted upper teeth, when clinical palpation was not clear, parallax technique was employed to determine the position of the crown, labially or palatally.

Surgical Technique

Most of the surgeries were carried out under local anesthesia using 2% lignocaine with 1:800 epinephrine. In some cases, and due to the complexity of the surgery or the age of the patient, the procedure was performed under general anesthesia although some local anesthetic with epinephrine was also infiltrated in the operative area for hemostasis.

A labial, buccal, or palatal flap was raised along the gingival margin and as far from the operative field as possible. The flap was retracted and the bone covering the crown was removed, either with a chisel or with a large round bur. Only sufficient amount of bone was removed to expose the crown to allow isolation and bonding of the bracket [Figs. 2a and b].

Since tags from the follicle might contaminate the etchant and nullify its effect, whenever isolation could not be insured, the tooth follicle, with reduced enamel epithelium, was incised and retracted gently to the side or removed. When a large bur was used to remove the bone from the crown surface, the engine was run at a low speed using effective coolant.

After a preligatured bracket was bonded to the crown surface, the mucoperiosteal flap was repositioned and sutured with 3-0 black silk [Fig. 3]. The wire, protruding through the mucosa, was cut to a suitable length and fashioned into a hook. The patients were placed on a suitable course of antibiotic and sutures were removed after one week and were followed-up by the orthodontist on a 4 to 6-week basis.

Orthodontic Treatment and Technique
Edgewise  fixed  appliances  were  used  in  all patients and the treatment was designed as follows.

All teeth were exposed and banded as planned. In some cases, a large amount of bone had to be removed. During this careful procedure, the bur may accidentally touched the surface of the crown but no serious lesion to the enamel or root cement was observed in all cases. All impacted central incisors were found to be due to the presence of a mesiodens which were always impacted in an inverted position with retained deciduous central incisors. The deciduous teeth were extracted and the impacted mesiodens were removed surgically, and the crowns of the impacted central incisors were exposed and a bracket was bonded on each incisor to effect orthodontic traction.

No post-operative complication, such as infection or severe pain, was observed. The orthodontic appliance was tolerated very well by the patients and there was no problem with the orthodontic treatment or the fixation, except in five patients where the bracket became dislodged. This was managed effectively and all patients were able to maintain an adequate and acceptable oral hygiene.

The observation and follow-up period varied between 1.5-4 years with a mean of one year and eight months. Although some of these teeth were followed for more than two years, most of the teeth were still under active treatment. The teeth were firmly affixed in the new position and in occlusion 2-2.5 years post-operatively.

The gingiva and the mucosa were free from inflammation and did not differ from the surrounding tissue around the protruding wire or the positioned teeth. The width of attached gingiva with stippled surface was within normal. The depth of the pocket around the teeth was between 1-3 mm. Slight recession was observed in three cases.

Radiographic follow-up showed normal bone established in the alveolus with no complication even in cases with great loss of bone caused by severe malposition of the impacted teeth during the operative technique. No root resorption or ankylosis was observed in any of the cases. The patient's attitude toward the procedure was positive and none of them complained about the orthodontic appliances.

Treatment of unerupted impacted teeth may utilize methods from both surgical and orthodontic specialties.⁴⁵ Teeth, other than the third molar, when impacted have different ways of treatment. These include either no treatment, exposure of the tooth and packing of the wound to prevent re- epithelialization, or removal when it is in a favorable position. When the tooth is high in the arch and causing some adjacent root resorption and other pathological changes, transplantation involving bodily removal from the site of impaction to the correct position within the line of the arch is performed. Another method is surgical repositioning which involves rotation of the upper tooth about its apex, without disturbing the neurovascular bundle on the assumption that tooth may erupt into occlusion.