Three-Dimensional Study on Pharyngeal Morphology in Mouth-Breathing Children

Objectives To investigate the pharyngeal morphological differences between mouth-breathing and nose-breathing children. Material and Methods Sixty-two children aged 8–10 years underwent cone-beam computed tomography (CBCT) examinations. They were divided into two groups based on breathing mode: mouth-breathing group (30 cases; males: 22, females: 8) and nose-breathing group (32 cases; males: 20, females: 12). The pharyngeal cavities were reconstructed three-dimensionally using Mimics software, with measurements of pharyngeal segment volume and length. Independent-samples t-tests were used for parameter comparisons. Results Total and segmental pharyngeal volumes were significantly smaller in the mouth-breathing group than in the nose-breathing group (P < 0.05), whereas pharyngeal length showed no significant difference (P > 0.05). Additionally, the volume-to-length ratio in the mouth-breathing group was significantly lower than in the nose-breathing group (P < 0.05). Conclusions Mouth-breathing children exhibit a significantly narrower pharyngeal morphology, characterized by reduced volume without changes in length, leading to decreased airway patency. This structural alteration correlates with increased respiratory resistance and has often been linked to maxillary constriction and posterior pharyngeal space reduction.