The Effect Of The Acoustic Characteristics Of The Removable Partial Denture In Maxillary Kennedy I Dentition Defect Before And After Restoration

Purpose: Analysis the acoustic characteristics of the removable partial denture in maxillary Kennedy I dentition defect before and after restoration. To investigate this kind of denture how to effects the acoustic characteristics. Offer acoustic theory base to the removable partial denture in maxillary dentition defect. Offer references to the design and improvement of the maxillary partial denture. Methods: Use the computer speech lab(CSL), analysis the acoustic characteristics of 12 maxillary Kennedy I dentition defect patients, before and after the restoration of the partial denture at the beginning, 1week,2weeks,4weeks and 8weeks. To compare each patient different time's formant (F1,F2,F3), the first formant band width (B1) of vowels /a/,/i/,/u/;the area of energy concentration(Fl,F2,F3), the first area of energy concentration band width (B1) of consonants /s/,/sh/,/j/; the locus of /t/,/l/.Results: There was no difference (P>0.05) in vowels formant (F1,F2,F3) and the first formant band width(B1)of each group data. There was significant differences (P<0.05) in the area of energy concentration (F1,F2)and the first area of energy concentration band width (B1) in consonant /s/ of the groups before restoration ,at the beginning and one week. There was no difference(P>0.05) in each group data of other consonants /t/,/l/,/sh/,/j/.Conclusion: The restoration with removable partial denture in maxillary Kennedy I dentition defect was no effect in vowels, there was effect in consonant /s/,and no effect in other consonants. The main area which effects the acoustic characteristics is the anterior part of the anterior palate plate of the removable partial denture. From the acoustics point of view, to lay the major connecter on the upper gingival, the median line area are not suitable, while the posterior part of the upper palate fitting to lay it.