The full upper edentulous working model with the full sulcus depth marked and relieved around the freanum attachments.
Using two thicknesses of wax (approximately 2mm thick), the wax is heated and formed to the upper model as shown. (There is no need to soak the model).
Three ‘windows’ are cut on top of the alveolar ridge (one on each posterior section of the ridge in the premolar region and one in the incisive papillae region).
These will eventually act as ‘stops’ within the special tray and maintain an even thickness of impression material during use.
These ‘windows’ are then filled with light cure special tray material.
A sheet of the special tray material is then formed to the upper working model and trimmed to shape.
A strip of the special tray material is cut, rolled and flattened / shaped to fabricate the handle. Take care to fabricate a handle that is not too long or wide to interfere with the lip during border moudling, but enough for the clinician to hold whilst taking the upper impression.
The handle is then attached to the upper tray as shown.
The handle should be central to the patient's mouth & vertical to the alveolar ridge.
Remember the handle must not interfere with the patient's upper lip during the impression taking stage. The clinican may have a preference as to the size and shape of the handle depending on each individual patient.
The handle may also be smoothed to blend into the upper tray, but this is not essential.
The formed special tray is then placed into a light curing box and allowed to go through its initial curing cycle. N.B. Support the handle to keep its angle / shape by resting it against the draw 'door'.
The upper working model and cured special tray are then boiled free of wax, then the upper tray is inverted and again placed into the light curing box to cure the inside of the handle area, which can be quite thick.
Once fully cured, the periphery of the upper special tray is then trimmed, rounded and smoothed, taking care to relieve the fraenum attachments.
The finished full upper special tray. N.B. Alcohol rubs and treatment sprays may be used to wipe around the periphery if necessary.
A second line is marked 2-3mm above the full sulcus depth, so the finished special tray is relieved from the sulcus; to allow space for border moulding.