Access below the zygomatic arch can be extended further by use of two methods:
The superficial part of the masseter is simply released from its origin along the anterior portion of the zygomatic arch and body and then detached from the lateral surface of the ascending ramus exposing the sigmoid notch and the coronoid.
A more elaborate technique is to perform a segmental osteotomy of the zygomatic arch. The segment is reflected laterally still pedicled to the masseter muscle, while the dissection proceeds between the bony surface of upper ramus and the underside of the muscle.
Note: Both these variants of subzygomatic exposure will compromise the vascular and neural supply to the masseter muscle with subsequent neurogenic muscular atrophy.
The masseteric neurovascular bundle given off from the maxillary artery, and the mandibular division of the trigeminal nerve respectively, emerge from the infratemporal fossa outward through the sigmoid notch and will be disrupted.