Speech intelligibility in patients with complete dentures according to the material used.

ABSTRACT

The principal purpose of this study was to investigate the speech of two edentulous subjects fitted with a complete maxillary prosthesis made of three different palatal materials aluminium, resin, stellite. The study was performed using two speakers fitted with a prosthesis (a man and a woman). They took part in the acoustic recording of logatoms read by themselves while wearing various prostheses. These recordings were tested from the auditory point of view by a series of six listeners (four men and two women) in an anechoic room. After 144 different tests, a speech reception threshold (SRT) was defined for each speaker and each different prosthesis. This SRT shows a level of speech intelligibility defined so that the lower the SRT, the more intelligible for the listener. The results show that (i) both the material and the listener influence SRT (P < 0.05); (ii) an interaction between the material factor and the speaker factor appears. (P < 0.05); (iii) The hierarchy factors influencing SRT are most important in the order Listener --> material --> speaker; and (d) The group fitted with a metal prosthesis (aluminium, stellite) was more intelligible regarding the way they were perceived by others.