Abstract
Palatolingual contact of the 20 cleft palate subjects judged to have defective articulation after palatoplasty (11 subjects having sufficient velopharyngeal closure after early operation and 9 other subjects) were observed by the dynamic palatography which was an electric device capable of recording constantly changing palatolingual contacts as a function of time by means of artificial palate equipped with numerous electrodes. The palatogram patterns obtained were classified to establish more objectiveproceduresto evaluate articulation and toput it to clinical use.
The items of classifications are as follows:
1. Continuity of contacts: open type (S and O), closed type (T and Max).
2. Position of contacts: frontal type, backward type (b).
3. Area of contacts: peripheral (1), broad (2).
4. Symmetry of contacts: symmetric, asymmetric (').
5. Position of opening: medial, lateral (").
The palatogram pattern at the time of maximum contact and production of Japanese consonants [s, dz, ts, f, d, tf, t, d, n, r] which were produced by the contact of the tongue with the alveolus or the hard palate wer e devided into 4 groups and 20 subgroups combining these items.
As the chracteristic patterns different from the normal, t he following types were observed: 1) Sb, Sb', Tb, Tb'type in which the position of contacts were deviated to the backward,2) Max type in which whole palate were closed with the tongue, and 3) O type in which palatolingual contact were not recognized.
The manner of articulation represented with the changes of the patterns fro m the time of the maximum contact to the production of consonants were devided into following 4 groups: 1) Release maintaining manner (S or O to S or O),2) Closure to release manner (S or O to T or Max),3) Closure maintaining manner (T or Max to T or Max), and 4) Untouched manner (O to O).
