An injection impression technique for palatal defects

Abstract

A master cast suitable for fabricating a retentive flexible base using any of the materials and techniques previously mentioned is provided. The flexible extension fits snugly into the defect laterally and extends above the remnants of the soft palate posteriorly and into the nasal floor anteriorly on either side of the remnants of the nasal septum (Fig. 9). The use of a thin flexible extension such as Molloplast will provide a good chemical bond to the acrylic resin of the denture base, allows for easy cleaning, and will maintain flexibility for several years. Prostheses constructed with this technique are retained well. The technique described will provide increased mechanical retention of prostheses for defects of the palate by engaging undercuts around the borders of the defect with a flexible material. The impression is made by injecting an elastic impression material with a syringe through a hole prepared in the palate of the impression tray. This technique may not always be required, but is recommended where a retention problem is anticipated and there is difficulty in obtaining a satisfactory flow of the impression material to the appropriate undercut. A correct impression can be secured the first time, overcoming further discomfort and inconvenience to the patient.