Changes in tongue–palatal contact during swallowing in patients with skeletal mandibular prognathism after orthognathic surgery

Abstract

This study aimed to evaluate improvement of tongue-palatal contact patterns during swallowing after orthognathic surgery in mandibular prognathism patients. Thirty patients with mandibular prognathism treated by orthognathic surgery (average age of 27 years, 3 months) and 10 controls (average age 29 years, 6 months) participated in this study. Tongue-palatal contact patterns of patients before and three months after surgery were evaluated by electropalatography (EPG) as well as controls. Whole total of tongue-palatal contact at 0.3, 0.2, and 0.1 sec before complete tongue-palatal contact during swallowing were evaluated. The duration of swallowing phases was also examined. Complete contact of tongue-tip in the alveolar part of individual artificial EPG plate were shown at 0.3, 0.2, and 0.1 sec before complete tongue-palatal contact in the controls, although incomplete contact in the alveolar part were shown at 0.3 sec in mandibular prognathism patients. Whole total of tongue-palatal contact at 0.3 and 0.2 sec before complete tongue-palatal contact was significantly lower in the patients before surgery than in the controls (p<0.05). However, these values increased after surgery. The duration of oral and pharyngeal phase was significantly longer in the patients before surgery than in the controls and the patients after surgery (p<0.01). This study demonstrated that the tongue-palatal contact pattern improved and the duration of oral and pharyngeal phase was shortened in mandibular prognathism patients during swallowing after orthognathic surgery. It is suggested that changes in maxillofacial morphology by orthognathic surgery can induce normal tongue movement during swallowing. (The data underlying this study have been uploaded to figshare and are accessible using the following DOI: https://doi.org/10.6084/m9.figshare.14101616.v1)

The Physiological Function of Deglutition and Swallowing in Patients With Maxillary Protrusion After Mandibular Advancement

“…Previous reports demonstrated that the tongue-palatal contact pattern during swallowing improved in patients with mandibular prognathism after orthognathic surgery using EPG. 10 Thus, EPG is quite useful for the observation of tongue-palatal contact area during swallowing. However, there is little information focused on tongue-palatal contact changes during swallowing pre and postoperative patients with maxillary protrusion.…”

“…To reproduce habitual swallowing, each subject sit on a chair with an upright posture and swallowed water (3 mL, 5 times) for data taking according to the previous study. 10,11 They received instructions to hold the eye-ear plane parallel to the floor. Ten seconds break was given between each swallowing and the motion of swallowing was also recorded by a video camera.…”

“…The duration from the beginning of tongue-palatal separation to complete separation is equivalent to the esophageal phase according in accordance with previous studies. 10,13…”

“…It was also demonstrated that the oral and pharyngeal phase duration became shorter after surgery. 10 Thus, EPG is useful to evaluate tongue movement during articulation and swallowing. However, there is no detailed report about tongue-palatal contact changes during swallowing in pre and postoperative patients with maxillary protrusion.…”

Impact of Maximum Tongue Pressure in Patients with Jaw Deformities Who Underwent Orthognathic Surgery

“…To ensure long-term postoperative stability, it is necessary to examine the stomatognathic functions of patients undergoing orthognathic surgery. Previous studies have reported that surgical orthodontic treatment improves masticatory ability, occlusal force, mandibular condyle and lip movement, and muscle activity [ 7 , 8 , 9 ]. In particular, not only tongue size or tongue habit but also tongue adaptation to changes in the volume of the oral cavity after the orthodontic surgery have been reported to have a great influence on treatment success [ 10 ].…”