Orthognathic Surgery in Anterior Open Bite

Anterior open bite is a frequent occlusal disorder that affects chewing, swallowing, speech, tooth loss, and aesthetics. Persistent infantile swallowing is a major cause of occurrence and relapse of anterior open bite after treatment. This retrospective cohort study aimed to identify factors affecting postsurgical relapse. The study included 50 surgically treated patients aged 15 to 47 with over 3-mm anterior open bite who were followed up postsurgically for 6 months. Sixteen patients (32%) relapsed. Compared with the nonrelapsed group, the relapsed group was older (35.81 versus 24.26 y; P<0.001), had smaller clockwise rotation occlusal plane amplitude (4.25 versus 14.29 degrees; P<0.001), lower maxillary expansion incidence (32% versus 68%; P=0.026) and degree (0.43 versus 1.26 degrees; P=0.009), less common addition of genioplasty (32% versus 68%; P=0.026), shorter rehabilitation (5.13 versus 6.76 mo; P=0.001), and a lower rate of speech therapy rehabilitation (18.75% versus 61.76%; P=0.003). Presurgical rehabilitation rate was similar in both groups (37.50% versus 61.76%; P=0.186). This study highlighted the impact rehabilitation (type and duration) and surgical decisions (clockwise rotation and maxillary expansion) have on postsurgical relapse of anterior open bite, underscoring their importance.