对上颌全口义齿后堤区的描述，以下哪项错误
A．后堤区可在口内形成
B．后堤区在后颤动线之后
C．后堤区平均宽8mm
D．腭穹窿较高，后堤区较窄
E．后堤区有利于边缘封闭
参考答案：B
解析：前颤动线在硬腭和软腭的连接区，约在翼上颌切迹于腭小凹的连线上。后颤动线在软腭腱膜和软腭肌的连接区。前后颤动线之间可稍加压力，作为上颌义齿后缘的封闭区，称后堤区。
| 阅读理解。 | ||||
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| 1. How did Daniel get to New York? | ||||
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| 2. What is Daniel's flat like? | ||||
| A. It's far away from his office. B. It's quite cheap C. It's very big. D. It's very nice. | ||||
| 3. What does Daniel NOT tell us? | ||||
| A. Whether he has visited New York before. B. Where he stayed before he found a flat. C. Why he had a party on April Fool's Day. D. What his workmates and new neighbours are like. | ||||
