Influence of Digit Sucking Habit on Masseter Muscle Thickness and Upper Airway Dimensions in Nigerian Children

Background: Digit sucking habit (DSH) generates functional forces that can influence craniofacial morphology. Although the dental effects have been widely reported, its influence on the masseter muscle thickness (MMT) and upper airway (UA) dimensions is not well known. Methods: Thirty (30) children selected from the orthodontic clinic (OAUTHC), with a DSH were matched with a group of 30 children without a DSH. Each group comprised of 16 males and 14 females. Ultrasonographic evaluation of the masseter muscle (MM) was performed to measure the left and right MMT in the relaxed and contracted states. Lateral cephalometric radiographs were obtained and 6 UA variables were measured on the x-ray. Data was analysed using SPSS version 20.0. Statistical significance was set at p0.05). The mean measurement of the width of the nasopharynx (P1) was significantly decreased among the DS group when compared with the non-DS group (p0.05). Conclusion: Digit sucking habit caused a statistically significant narrowing of the width of the nasopharynx (p