Upper and lower working models are articulated (simple hinge articulator used here).

Anomalies are removed in the usual manner and a wax relief is placed at the distal of the 6/6 arch wire area.

A Fly-over clasp (sometimes known as a Plint clasp) is then fabricated as shown on both sides. The retentive 'tags' may be extended along the full length of one half of the arch, so both retentive 'tags' on each Fly-over clasp meet and cross over at the 1/1.

The retentive tags shouldn't interfere with the occlusion and be kept away from the buccal / palatal surfaces of the teeth.

Both upper and lower working models are waxed out as shown, ensuring that the wax doesn't impinge on the occlusion.

After soaking both upper and lower models for 10 minutes, the upper model is sprayed up as shown using cold cure acrylic resin

The models placed on the simple hinge articulator, closed together and cured to the manufacturer's instructions using a hydro flask. N.B. Green acrylic has been used here.

The cured Mandibular Osteotomy Splint is boiled free of wax, trimmed and polished as shown.