Prosthetic treatment for speech disorders due to surgically acquired maxillary defects.

To evaluate speech following prosthetic obturation of surgically acquired maxillary defects, the speech intelligibility of eight patients was measured preoperatively and postoperatively, with and without prostheses. Oro-nasal separation and velopharyngeal function were also evaluated by use of a specially designed spirometer and endoscope. Following placement of maxillary obturator prostheses, four patients achieved dramatic improvement in speech intelligibility, while four patients did not. In the latter, insufficient improvement in speech intelligibility was attributed to velopharyngeal incompetence or unstable prosthesis. Two of three patients with velopharyngeal incompetence did achieve adequate improvement in speech following placement of a speech appliance in combination with maxillary obturator prostheses.