Orthodontic treatment of a case with a congenitally missing maxillary canine and a malformed contralateral canine

Excluding third molars, the prevalence of tooth agenesis of permanent teeth ranges from 1.6% to 9.6%. The congenital absence of maxillary permanent canines is a rare condition with a reported prevalence of less than 0.5%. Case reports describing congenitally missing permanent canines are uncommon, and those that involve treatment are even more rare.

This case report describes the orthodontic treatment of a 12-year-old male patient who presented with a congenitally missing upper left permanent canine compounded by a malformed upper right permanent canine. Additionally, the patient had a retained upper left deciduous canine, a Class I molar relationship, an anterior open bite, and proclined and protruded incisors.

Treatment involved upper left first premolar substitution for the congenitally missing canine following the extraction of the upper left retained deciduous canine, the upper right first premolar, and both lower first premolars. The upper right malformed permanent canine was retained. The total treatment time was 32 months and the result remained stable 19 months later.