| 摘要 |
An orthopedic appliance for improving or correcting the overbite and overjet of persons having an abnormal, Class II relationship between the maxillary (upper jaw) and mandibular (lower jaw) bones and their respective teeth, where the mandible and its teeth are posteriorly displaced. Two hinges with telescoping members are used to join an upper molar and lower molar on both sides of the mouth. The point of attachment of each lower hinge is somewhat forward on the lower molar than the corresponding point on the upper molar when the appliance is installed so that closure of the mouth forces the lower jaw forward. In children, and adults to a limited extent, this produces permanent, "muscle-resting length" changes and also induces growth and changes of the lower jaw and its joint. As a result, there is a permanent correction of the occlusions to a normal, Class I bite after the appliance is worn for a period of time.
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