Frequency of Arch forms in a Pakistani sample and its association with the Curve of Spee and Gender

Abstract

Introduction: Arch form and curve of Spee are two important parameters in diagnosing malocclusion before the start of orthodontic treatment. The study aimed to determine the frequency of different dental arch forms in the Pakistani population and their association with the Curve of Spee (COS).

Material and Methods: The study used 322 mandibular pretreatment casts obtained from patients reporting for orthodontic treatment at the Orthodontic Department, RIHS, Islamabad. Arch forms and COS were measured on the casts. The frequency of arch forms and the association between COS and gender were assessed with the help of statistical analysis.

Results: The study found that the majority of the sample had (40.37%) square AF followed by (43.48%) round, and (16.15%) oval AF. There was a significant association between the dental arch form and gender, with males having square and females having round arch forms predominantly. Most of the square and round AF had normal COS, while oval AF had medium COS. The Spearman correlation between arch form and COS was statistically insignificant.

Conclusion: This study helped in the diagnosis of arch form type with respect to gender and enhanced the knowledge about the depth of COS in three different types of arch forms in the context of orthodontic treatment planning.