[The role of inter-dental consonant si in treating articulation disorders].

Purpose: The aim of this study was to rectify deviant tongue position and make accurate pronunciation via making use of the protrusion and containment effect of interdental consonant [si] for the tongue.

Methods: One hundred and fifty-seven patients with articulation disorders (postpalatoplasty and non-cleft palate) which were diagnosed as velopharyngeal sufficiency were included in this study. There were 111 males and 46 females, aging from 5 to 28 years old. Among them,29 patients were pharyngeal fricative, 73 patients were palatalized misarticulation, 36 patients were lateralization misarticulation and 19 patients were misarticulation mixed with palatalized and lateralization. During the treatment, the patients were asked to stick out the tongue to make the tooth gently biting it and pronounce a interdental consonant si smoothly. When the tongue was fully protracted, the tongue was retracted to the lingual side of mandibular anterior teeth to produce a normal apex linguae consonant [s].

Results: This training method had a significant effect for patients with articulation disorders. The effect was most significant for patients with pharyngeal fricative, with a effective rate of 96.55%(28/29), followed by 91.78%(67/73) in palatalized misarticulation, 84.21%(16/19) in palatalized mixed with lateralization misarticulation, and 77.78%(28/36) in lateralization misarticulation.

Conclusion: Training the pronunciation of interdental consonant [si] may control the retrusion, arching and curling movement of tongue, which therefore provides an effective treatment for articulation disorders such as pharyngeal fricative, palatalized and lateralization misarticulation. Supported by Research Fund of Science and Technology Commission of Shanghai Municipality (Grant No.08DZ2271100), Shanghai leading Academic Discipline Project (Grant No.S30206), Research Fund of Bureau of Health of Shanghai Municipality(Grant No.2008160) and Phosphor Science Foundation of Educational Commission of Shanghai Municipality (Grant No.2000SG41).