Prevalence and distribution of permanent canine agenesis in dental paediatric and orthodontic patients in Hungary.

Non-syndromic permanent canine agenesis, or combined with agenesis, or developmental absence of other tooth types, has occasionally been described in the literature, but isolated forms are rarely observed. The purpose of the present retrospective radiographic study was to provide data on the prevalence and distribution of permanent canine agenesis in the Hungarian population. Dental panoramic tomograms and the medical history data of 4417, 6- to 18-year-old children (average age 12 years, male-to-female ratio 1:1), who presented for treatment at the Department of Paediatric Dentistry and Orthodontics of the Semmelweis University Budapest, Hungary, were examined. Patients with systemic diseases were excluded. Chi-square and Fisher's tests were performed to determine statistical significance at a level of P < 0.05. Thirteen subjects had permanent canine agenesis. The overall prevalence was 0.29 per cent. The prevalence of permanent canine agenesis was 0.27 per cent in the maxilla and 0.09 per cent in the mandible (P < 0.01). The male-to-female ratio was 1:2.2. Dental anomalies associated with permanent canine agenesis were found: 11 patients had retention of the primary canines, 10 other types of agenesis of the permanent teeth, one a primary supernumerary tooth, one a supernumerary cusp, and nine occlusal disturbances.