According to SAWHNEY'S classification of TMJ ankylosis, complete joint architecture is destroyed by osseous union and no sigmoid notch is identifiable, this is:

SAWHNEY'S GRADING OF ANKYLOSIS  TYPE 1: Flattening or deformity of the condyle with little joint space seen on the radiograph. Extensive fibrous adhesions seen during operations.  TYPE 2: Bony fusion of the outer edges of the articular surfaces with no fusion in the deeper areas of the joint.  TYPE 3: A bridge of bone is seen between ramus of the mandible and zygomatic arch.  TYPE 4: Entire joint is replaced by a mass of bone.