Management of a complete 180° rotation of bilateral maxillary canines

Background: Dental anomalies usually lead to complicated decisions having to be made in terms of the orthodontic treatment of permanent dentition; tooth rotation is the most common of these irregularities. The prevalence rate of this phenomenon is 2.1–5.1% in patients who have not received orthodontic treatment. Purpose: This case report aimed to manage the complete bilateral rotation of maxillary canines with couple force by using a Nance appliance modification. Case: A 17-year-old male patient came in wanting to straighten his teeth. He complained about his bilateral canines, which were not in a normal position. There was an impacted left maxillary second premolar and an ectopically erupted right maxillary first premolar. He also had protrusions in the upper and lower anterior teeth and crowding in the lower anterior teeth as well as upper and lower midline deviations. Case Management: A clinical examination showed a class I relationship between the dental and cephalometry measurements and highlighted a class I skeletal pattern. The upper right first premolar was extracted and the left second premolar had undergone an odontectomy to allay protrusion and correct crowding. Bilaterally rotated upper canines were derotated using a modified Nance appliance and an elastomeric chain with couple force. Conclusion: The success of the orthodontic treatment was influenced by the specific nature of the patient's dental and medical history, extraoral and intraoral examination, diagnosis and treatment planning, which was followed by a systematic approach to treatment. The Nance appliance modification reduced the total treatment time by achieving controlled anchorage and derotation of the canines.