| Autor: |
William Earl Morrison, Heinz O. Beck |
| Rok vydání: |
1962 |
| Předmět: |
|
| Zdroj: |
The Journal of Prosthetic Dentistry. 12:873-883 |
| ISSN: |
0022-3913 |
| DOI: |
10.1016/0022-3913(62)90040-9 |
| Popis: |
The dynamic duplicator uses the factor of time in mandibular movements as it relates to instantaneous positions. The duplicator embodies the principle that the motion of a rigid body can be described by the instantaneous positions of three reciprocating points which do not lie on the same straight line and which are confined within three mutually perpendicular planes. At any given instant, each point can be at only one position. Each of the three points is the active part of the reproducing device. The value of the dynamic duplicator lies in the fact that there are no limitations in reproductions of movements of the mandible because of the construction of the mechanism. Initial and terminal positions as well as all intermediary positions can be included in the duplicated mandibular movements. The manner of attachment to the lower jaw by the mandibular frame imposes no greater restriction to function than a conventional hinge-bow. The important values of this mechanism follow: 1. The duplicator is an exact geometric counterpart of the recording apparatus in its spatial relationship with the maxillae and the mandible. 2. The dynamic duplicator has no degree of freedom, and it is mechanically and electronically controlled by the mandible. 3. The duplicator will produce identical information as received from the patient instead of equivalent values. 4. The time-displacement relationship is not incorporated in the conventional use of positional records and pantographic tracings. Instruments which are designed to duplicate the skull use points in movements which are passive rather than active. The instantaneous positions of the points are determined by other points in the guides of the instruments. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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