Prevalence of Congenitally Missing Mandibular Incisors in A Sample of Kurdish Patients Seeking Orthodontic Treatment


  • Anwar A. Amin Pedodontic, Orthodontic, and Preventive Dentistry Department, College of Dentistry, University of Sulaimani, Kurdistan Region, Iraq. Author



Prevalence, Congenitally missing, Mandibular incisors, Orthodontic patients


Objectives: This study's objective was to evaluate the prevalence of congenitally missing mandibular incisors (central and lateral incisors) in Kurdish patients seeking orthodontic treatment.  

Methods: The data were captured from 4056 patients (2596 females and 1460 males) seeking orthodontic treatment and included orthopantomograms, intraoral photographs, study models, while anamnestic data were retrieved and examined to evaluate the prevalence of congenitally missing lower incisors. A Chi-square test was used to determine significant differences.      

Results: The prevalence of missing lower incisors was 1.28%, with no statistically significant difference between males and females. A total of 73 permanent lower incisors were missing, with an average of 1.42 teeth per patient. Missing unilateral (59%) was more frequent than missing bilateral (41%). Within the unilateral cases, the left side tooth was more frequently missing than the right side, and the central incisor was the most frequently missing tooth. In addition, missing unilateral was more frequent in females, and missing bilateral was more frequent in males. In most subjects (76%), where mandibular incisors were missing, there were no other missing teeth.  

Conclusions: The prevalence of hypodontia can vary in different ethnic groups. In the Kurdish population, the prevalence was comparable with other ethnic groups, and the most frequently missing lower incisor was the left central incisor, followed by the right central incisor. Furthermore, missing unilateral was more frequent than missing bilateral.


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How to Cite

Prevalence of Congenitally Missing Mandibular Incisors in A Sample of Kurdish Patients Seeking Orthodontic Treatment. (2021). Sulaimani Dental Journal, 8(1), 7.