Frequency of different mandibular arch forms among patients attending a Tertiary Care Hospital in Karachi.

Abstract

Background:

The morphology of the mandibular dental arch varies across individuals and populations, influenced by factors such as gender, ethnicity, and malocclusion. Recognizing arch form differences is essential for achieving functional stability and esthetic balance in orthodontic treatment. This study aimed to determine the frequency and distribution of different mandibular arch forms tapered, square, and ovoid among orthodontic patients visiting Karachi Medical and Dental College (KMDC), and to evaluate the association between arch form and gender.

Methodology:

A descriptive cross-sectional study was conducted at the Department of Orthodontics, KMDC, Karachi, from January to June 2024. A total of 220 patients aged 12–35 years were selected through convenience sampling. Mandibular arch forms were assessed on dental casts using 3M Unitek preformed templates (tapered, square, and ovoid). Data were analyzed using SPSS version 20.0. Frequencies and percentages were calculated for categorical variables, and mean ± SD for age. The Chi-square test was applied to assess the association between gender and arch form, with p ≤ 0.05 considered statistically significant.

Results:

Of the 220 participants, 52 (23.6%) were males and 168 (76.4%) females, with a mean age of 19.33 ± 4.45 years. The ovoid arch form was most prevalent (39.1%), followed by the tapered (33.6%) and square (27.3%) forms. Gender-based differences were significant, as males predominantly exhibited tapered arches (46.2%) while females showed a higher frequency of ovoid arches (44.0%) (p = 0.019).

Conclusion:

The ovoid arch form was the most common among orthodontic patients, with significant gender differences observed. These findings provide valuable reference data for orthodontic diagnosis, archwire selection, and population-based treatment planning in Pakistani patients.