| 摘要 |
<p>The appliance consists of trays (1, 2) shaped to fit over the upper and lower jaw arches connected by side bars (3) that retract or advance the lower jaw when the jaws are opened and closed. Each side bar has spherical ends (3a) that engage with cups (4) in the tray side projections (1a) to form ball joints. Each of the cups is hemispherical in shape with an opening (4a) to receive the bar end.</p> |
