Anatomical study of the effects of five surgical maneuvers on palate movement.

The anatomy of the palate has been extensively described, with a predominant focus on palatal musculature. There are no biomechanical studies investigating the effects of surgical maneuvers on the palate to aid cleft closure. This study aims to describe the soft tissue attachments at different zones and quantify the movement following their release. Fourteen adult cadaver heads were dissected. The palates were split in the midline and five maneuvers described: Step 1, over the hard palate; Step 2, around the greater palatine pedicle; Step 3, over the palatine aponeurosis; Step 4, over the hamulus; and Step 5, resulting in a hamulus fracture. The movements across the midline at the posterior nasal spine following each maneuver were measured. The age range of the 14 heads was between 60 -75 years. Completion of steps 1 and 2 over the hard palate obtained a mean release of 2.6 and 2.0 mm, respectively. The largest movements occurred at Step 3 (5.7 mm) and Step 4 (3.5 mm), after releasing attachments at the posterior hard palate and palatine aponeurosis. Steps 3 and 4 dissections exhibited cumulative release, with a maximum movement with Step 3 (p < 0.05). Isolated fracture of the hamulus (Step 5) yielded a mean movement of 1.4 mm. Individual steps of dissection are described with respect to releasing soft tissue attachments. Medial movement of the oral mucosa is quantified with each step of dissection. The greatest release occurred with dissection overlying the palatine aponeurosis posterior to the hard/soft palate junction. Additional dissection along the hamulus (without fracture) added significantly to this release.