elevator. Clean retraction, without tissue tags adhering to the bone, is necessary for healing by primary intention.

Because hamular notch morphology is subtle and difficult to accurately record because of tissue inelasticity, tight muscle attachments, and the ramus' close proximity, use of the pterygoid extension implant prototype is recommended. The prototype (12) is fitted around the tuberosity and firmly compressed against the pterygoid process with a narrow periosteal elevator.

The anterior restoration (13) should be included in the impression. Thus it is seated, but not cemented, before the impression material is applied. The restoration may be seated before or after the prototype is fitted to bone, depending upon whether or not it would inhibit access to the more posterior site.

With the patient's mouth open and an assistant bracing the prototype against the buccal face of the tuberosity (14) and in the notch (15), moldable impression material is applied to the palatal arm of the prototype (16) and worked anteriorly on the palatal side of the alveolar ridge (17). That area of the ridge to be covered by the anterior extent of the palatal strut is carefully packed. Also, it is imperative that some of the impression material is extended over and covers the cantilevered pontic (18) and the occlusal surfaces of the crowns for a proper bite registration.

The patient is now brought into centric relationship and told to press his or her tongue against the impression material on the palatal side. The tongue will keep the impression material flush with the palatal side of the alveolar ridge, and prevent excess material packed from the buccal side from flowing behind the tuberosity and into the throat.

With the impression material braced by the tongue, additional material is applied to the buccal tuberosity arm of the prototype. Then in a backward and bucco-palatal direction (19), all excess impression material is pushed distal to the tuberosity and over the hamular notch area.

If a bilateral pterygoid impression is needed, the patient must be able to re-bite into centric relationship without interference from superfluous impression material. Thus the operator holds the set unilateral impression firmly against the bone (20), and asks the patient to open his or her mouth. With a scalpel (21), all excess impression material that might interfere with reclosure is removed. The buccal flange (22) is cut away, and sometimes material is removed from the palatal portion of the impression.

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