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Tooth impactions are prevalent in clinical practice.
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Mandibular third molars are the most frequently impacted teeth, followed by maxillary third molars, maxillary canines, mandibular premolars, and maxillary incisors.
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Diagnosis is based on clinical examination coupled with imaging, especially cone beam CT (CBCT) scans.
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Good Orthodontic mechanics, surgical planning, and patient education is essential to success.
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Surgical considerations include local anatomic concerns, anesthesia method, flap design,
Oral and Maxillofacial Surgery Clinics of North America
Orthodontic and Surgical Considerations for Treating Impacted Teeth
Section snippets
Key points
Epidemiology
Impacted teeth are often the most challenging condition that an orthodontist encounters. The prevalence of impacted teeth ranges from 1% to 3.5% in the general population,1 but is as high as 23%.2 The mandibular third molars are the most frequently impacted teeth, followed by maxillary third molars, maxillary canines, mandibular premolars, and maxillary incisors.3, 4, 5 The prevalence of maxillary canine impactions has been reported to range from 0.8% to 2% in the general population. Most (85%)
Etiology
A wide range of systemic and local factors have been shown to be associated with impacted teeth.1,3,12 Some of the systemic factors that have been implicated include: endocrine deficiencies (hypothyroidism), cleidocranial dysplasia, and craniofacial dysostosis syndromes. Local factors include: severe teeth size/arch length discrepancies, failure of root resorption of roots primary teeth, early loss of primary teeth and associated space loss, presence of supernumerary teeth, and trauma.1,3,12
Diagnosis
The earliest sign of an impacted maxillary canine is an absence of a canine bulge during routine orthodontic examinations at around 9 years of age when patients initially present for an orthodontic consultation. Panoramic and periapical radiographs have routinely been used to diagnose impacted teeth (Fig. 1). The case illustrated in Fig. 1 is a panoramic radiograph that was exposed during an orthodontic consultation. The initial clinical examination of a 15-year-old patient showed a full
Orthodontic preparation and surgical exposure of impacted maxillary canines
Aside from the third molars, the maxillary canines are the most frequently impacted teeth. In the following paragraphs, we provide an overview of orthodontic preparation and various surgical exposure techniques used for treating impacted maxillary canines. The surgical method used for exposures is largely dependent on individual preferences and is driven by the mesiobuccal location of impacted tooth (labial, palatal, or intra-alveolar), patient compliance with oral hygiene practices, and
Closed surgical exposure
Before surgical exposure of impacted teeth, the orthodontist must prepare the maxillary arch (align, level, and create sufficient space for placing the impacted tooth in its correct position in the arch) and communicate with the oral and maxillofacial surgeon about the planned orthodontic traction mechanics so that the gold chain can be bonded by the oral and maxillofacial surgeon at the ideal location on an exposed tooth. Ideally, it is recommended that the orthodontist be present at the time
Open surgical exposure
In the open eruption technique, the bone is completely removed from the coronal aspect of the tooth.19,20 A full-thickness flap is elevated from the first premolar to the midline. The bone encasing the impacted canine is gently removed until the crown of the tooth is exposed. The flap is sutured back while leaving a window for the exposed tooth to erupt. Typically, a periodontal dressing is placed over the surgical area and replaced periodically. Alternatively, the surgeon may just excise a
Procedures for treating labially impacted canines
Labially impacted maxillary canines can be uncovered by excisional uncovering (gingivectomy), apically positioned flaps, or by the closed eruption technique.19 The most appropriate method for exposure of an impacted tooth is dependent on the labiolingual position of tooth, vertical position of the tooth relative to mucogingival junction, amount of gingiva in the area of the impacted tooth, and mesiodistal position of the canine in relation to the root of lateral incisor.19 If a crown is coronal
Complications of treatment
Keys to realizing excellent outcomes include: diagnosing and localizing the impacted tooth/teeth, establishing a treatment plan tailored to the patient, communication between the orthodontist and oral and maxillofacial surgeon at the time of surgical exposure, and well planned orthodontic mechanics to move the impacted teeth. A breakdown in any of these can lead to poor outcomes. Some of the common pitfalls encountered in such situations are illustrated by the following cases.
One of the adverse
Surgical considerations
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Planning
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Maxilla versus mandible for site-specific anatomic structures
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Radiographs
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CBCT
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Most definitive for determining position of impacted tooth and adjacent structures, such as neighboring teeth, nerves, and path of eruption
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Anesthesia
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Operating room versus office
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Local anesthesia versus intravenous sedation
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Flap design
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Facial full-thickness mucoperiosteal flap with distal release versus envelope flap without release versus tissue punch
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Flap size and exposure, especially on palatal aspect, to ensure
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Summary
Impacted teeth occur in a significant number of patients and require the coordinated efforts of orthodontists and oral and maxillofacial surgeons. Specifically, optimal results require a prompt orthodontic diagnosis and treatment plan with execution of either closed or open exposure of impacted teeth by the oral and maxillofacial surgeon. Failure to consider orthodontic mechanics and improper surgical technique can lead to suboptimal results. Thus, orthodontist/oral and maxillofacial surgeon
Disclosure
The authors have nothing to disclose.
References (21)
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Radiographic examination of ectopically erupting maxillary canines
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The incidence of impacted teeth. A survey at Harlem hospital
Oral Surg Oral Med Oral Pathol
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Etiology of maxillary canine impaction: a review
Am J Orthod Dentofacial Orthop
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Three-dimensional localization of maxillary canines with cone-beam computed tomography
Am J Orthod Dentofacial Orthop
(2005) - et al.
Palatally impacted canines: the case for closed surgical exposure and immediate orthodontic traction
Am J Orthod Dentofacial Orthop
(2013) Surgical and orthodontic management of impacted maxillary canines
Am J Orthod Dentofacial Orthop
(2004)- et al.
Palatally impacted canines: the case for preorthodontic uncovering and autonomous eruption
Am J Orthod Dentofacial Orthop
(2013) Evidence-based surgical-orthodontic management of impacted teeth
Atlas Oral Maxillofac Surg Clin North Am
(2013)
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2024, Journal of Prevention and Treatment for Stomatological DiseasesMorphological types of sella turcica bridging and sella turcica dimensions in relation to palatal canine impaction: a retrospective study
2023, Journal of Clinical Pediatric Dentistry