Comprehensive Study on Quantitative Evaluation of Oral Muscle Tissue in Children With Low Tongue Posture Using Cone...

Low tongue posture (LTP) results from nasal obstruction and impaired oral muscle function. However, the relationship between nasal obstruction-independent LTP and oral muscle function remains unclear.

In this study, we aimed to comprehensively examine the relationship between nasal obstruction-independent LTP and oral muscle function by evaluating LTP, nasal ventilation conditions, and oral muscle function based on the cross-sectional area of the muscle-fat tissue surrounding the oral cavity.

Participants included 28 children (LTP group: mean age: 8.71 years) with LTP and 24 children (control group: mean age: 8.89 years) without LTP. Nasal airway ventilation conditions were evaluated using nasal fluid analysis of the cone beam computed tomography (CBCT) data. Oral muscle function was assessed by measuring the cross-sectional area of muscle-fat in the upper and lower lips, upper and lower oral vermilions, and tongue using CBCT data.

Compared with the control group, the LTP group exhibited higher nasal airway pressure and reduced muscle cross-sectional areas in the lower lip, lower orbicularis oris, and tongue. The LTP group without nasal obstruction had significantly smaller muscle cross-sectional areas of the lower lip and tongue than the group without LTP. The group without LTP but with nasal obstruction had a significantly larger tongue muscle cross-sectional area than the LTP group.

LTP can involve nasal obstruction and reduced muscle components in the lower lip, orbicularis oris, and especially the tongue, being related to lower muscle function. The findings could help improve the management of LTP-associated disorders.