Measurement of palatal surface sensation by neuro-sensory tests in the postoperative cleft palate patients.

To clarify the effects of abnormal sensation on the palatal surface on speech sounds in postoperative cleft palate patients, we measured palatal surface sensation in these patients. Tactile and vibratory sensation were measured quantitatively using a SW sensemeter and a vibrometer. The obtained values were compared with those in controls. The following results were obtained. In both the postoperative cleft palate patients and controls, the sensation in the anterior region of the hard palate was more numb than that in the anterior region of the soft palate or the premolar alveolar region. The tactile sensation in the postoperative cleft palate patients was more numb than that in the controls. In particular, a marked difference was observed in the premolar alveolar mucosa. The vibratory sensation in the postoperative cleft palate patients, however, did not clearly differ from that in the controls. There was a positive correlation between the tactile sensory threshold and the vibratory sensory threshold in the controls. No association between the two thresholds was observed in the postoperative cleft palate patients. The authors concluded that the tactile sensation at premolar alveolar region in the postoperative cleft palate patients was more numb than in the controls. This abnormality may affect speech development.