The Effects Of Palatal Rugae On The Acoustic Characteristics After Restoration With Complete Denture

Objective:To study the effects of palatal rugae on speech recovery after restoration with complete denture.Methods:30 edentulous patients were selected for this study.All the patients were restored with metal base complete denture,which were classified into two groups:The first group concluded 15 patients whose complete denture didn't have palatal rugae,and the second group concluded 15 patients whose complete denture had palatal rugae.Analyse the second formant(F₂) and the second formant band width(B₂) of vowels/a/,/i/,/u/,the second area of energy concentration(F₂) and the second area of energy concentration band width(B₂) of consonants/j/,/q/,/s/,/sh/,the voice onset time(V.O.T.) of consonants /j/,/q/by use of MiniSpeech Lab before and after the restoration at the beginning and then at 1,2,4 and 8w.Results:(1)/j/In the first group,compared with before restoration,there were statistical differences(P＜0.05) in F₂ at 2,4 and 8w and statistical difference(P＜0.05) in B₂ at 8w. In the second group,compared with before restoration,there were statistical differences (P＜0.05) in F₂ at 1,2,4 and 8w and statistical differences(P＜0.05) in B₂ at 2 and 8w. Compared between the two groups at the same time,there were statistical differences(P＜0.01) in F₂ at lw and statistical differences(P＜0.05) at 2w in B₂.(2)/q/In the first group,compared with before restoration,there were statistical differences(P＜0.05) in F₂ at 2,4 and 8w and statistical difference(P＜0.05) in B₂ at 4w. In the second group,compared with before restoration,there were statistical differences (P＜0.05) in F₂ at 1,4 and 8w and statistical differences(P＜0.05) in B₂ at 4 and 8w. Compared between the two groups at the same time,there were statistical differences(P＜0.05) in F₂ at 1w.(3)/s/In both of the groups,there were statistical differences(P＜0.05) in F₂ and B₂ after the restoration at the beginning,and then 1,2,4 and 8w compared with before restoration.Conclusion:(1) Palatal rugae of metal base complete denture has no effect on vowels but has effect on consonants/j/,/q/. (2) Palatal rugae can shorten the time which is needed by the speech recovery after restoration with metal base complete denture.(3) In clinical practice,it is necessary to make palatal mgac of patients'own shape to promote the speech recovery after restoration with metal base complete denture.