著者

重政 理香 高野 伸夫 中野 洋子

出版者

特定非営利活動法人 日本顎変形症学会

雑誌

日本顎変形症学会雑誌 (ISSN:09167048)

巻号頁・発行日

vol.25, no.4, pp.241-248, 2015-12-15 (Released:2015-12-25)

参考文献数

24

被引用文献数

2 2

---

Objective: There have been many previous reports about the relationships between jaw deformity and articulation disorders, but most of such studies were conducted in cases with mandibular prognathism. In contrast, well-defined studies have not been conducted to date in patients with retrognathia although it is considered that such patients have articulation disorders because of the relationship with tegmentum in the anterior tooth area and association with abnormality of the perioral muscles. We previously reported on the effects of orthognathic surgery on vowel sounds in patients with retrognathia. The purpose of this study was to investigate the influence of orthognathic surgery on poor articulation of Japanese consonants in cases with retrognathia. Materials and Methods: The eight consonant sounds [ka], [ki], [sa], [ɕi], [ta], [tɕi], [pa], [pi] were recorded as speech samples. The investigation was carried out in 11 Japanese female patients with mandibular retrognathia requiring surgery for jaw deformity and malocclusion both at the preoperative and postoperative stages of 3 and 6 months. These subjects were compared with 10 healthy controls. The duration of the consonant sound and the sound pressure level were analyzed. Results: The duration of the consonant sounds [ka], [ki], [ɕi] and [tɕi] was significantly longer in patients with mandibular retrognathia compared with the controls. The duration of the consonant sounds except [pa] and [pi] after the operation was generally shorter than before the operation. Especially, significant shortening was observed in [ki] in the comparison between before and 6 months after the operation. The sound pressure level for [ki] and [tɕi] was significantly smaller. No significant differences were found in the sound pressure level of the consonant sounds between before and after the operation, but the level was getting larger by 6 months after the operation. Conclusion: In patients with mandibular retrognathia, the duration of consonants was extended especially in the alveolar fricative sound, velar plosive, and alveolar affricate; furthermore, the sound pressure level was low. However, the articulation disorders tended to be reduced at 6 months after orthognathic surgery by correcting the occlusion and jaw position.