Stepbystep Technique

1. Practice the three excursive positions with the patient until they can be reproduced. The patient can be guided into an anterior end-to-end position and left and right lateral positions where the canines are end-to-end when viewed from the front. We have found guiding the patient helpful in obtaining the records easily, although unguided records have been equally accurate .25

2. Adapt a wax record to the maxillary arch (Fig. 2-28, A) and guide the patient into a protrusive position. Have the patient close to form indentations in the recording medium (Fig. 2-28, B). Verify that the midline remains properly aligned and that when viewed from the side, the maxillary and mandibular incisors are end to end.

3. For the lateral records, add additional wax to one posterior quadrant of a wax record to compensate for the additional space on the patient's nonworking side.

4. Adapt this to the patient's maxillary arch and guide the patient's mandible into an excursive position, again verifying that the canines are end to end (Fig. 2-28, C, D).

5. Repeat this step for the other lateral excursion.

6. Mark each record to facilitate its identification when using it to adjust the posterior ar-ticulator controls (Fig. 2-28, E).

Simplified Pantographs (Fig. 2-29). A simplified pantograph measures only certain components of mandibular movement thought to be of greatest clinical significance, usually the condylar inclinations and mandibular sideshift. This device can be quickly assembled. Numerical values are measured directly from the recording and are used to set a semiadjustable articulator to provide useful diagnostic information.

Simplified pantographs may reveal an excessively shallow condylar inclination or an exaggerated mandibular sideshift. If either of these conditions are identified, restoration of the posterior teeth is likely to be complex, and the use of a fully adjustable articulator is recommended. Some manu

Pantograph Articulator
Fig. 2-28. Eccentric interocclusal records. A, Adaptation of wax to the maxillary arch. B, Protrusive record. C and D, The patient is guided into left and right lateral excursive movements. Records are made in the left and right canine edge-to-edge positions. E, The completed records.
Bennet Movements Mandible
Fig. 2-29. A, The Panadent Axi-Path Recorder. B, An axis stylus traces the condylar-path and measures the amount of Bennett movement while the patient is guided into an eccentric border movement (C). (A to C courtesy Panadent Corporation.)

facturers offer inserts of standard "fossae" of varying configuration, whose selection depends on the measurements obtained with a simplified pantograph (Fig. 2-30).

Pantographic Recordings (Fig. 2-31). Fully adjustable articulators are usually programmed on the basis of a pantographic recording. Jaw movements are registered by directional tracings on recording plates. The plates are rigidly attached to one jaw, and the recording styli are attached to the other. A total of six plates are needed to achieve a precise movement record of the mandible. Left and right lateral border and protrusive tracings are made on each plate. The pantograph is then attached to the articulator, and the controls are adjusted and modified until the instrument can faithfully reproduce the movements of the styli on the tracings (Fig. 2-32). A simpler, though less accurate, procedure is to measure the tracings directly and adjust the condylar controls without transferring the recordings.

Electronic Pantograph (Fig. 2-33). The Axio-graph* is an electronic pantograph designed to record and measure functional and border movements. It consists of upper and lower bows that record and measure mandibular movements.

*Great Lakes Orthodontics: Tonawanda, N.Y.

Mandibular Pantograph

Panadent preformed motion analog paths

Mandibular Pantograph

Fig. 2-30. A, The Panadent PCH Articulator with support Legs. B, Fossa blocks (motion analogs) with different amounts of Bennett movement are selected from the simplified recorder or lateral check bites. The blocks are rotated to the correct condylar inclination. C, Schematic showing the sagittal and transverse planes of the available motion analogs blocks.

(A to C courtesy Panadent Corporation.)

Fig. 2-30. A, The Panadent PCH Articulator with support Legs. B, Fossa blocks (motion analogs) with different amounts of Bennett movement are selected from the simplified recorder or lateral check bites. The blocks are rotated to the correct condylar inclination. C, Schematic showing the sagittal and transverse planes of the available motion analogs blocks.

(A to C courtesy Panadent Corporation.)

Stewart Articulator
Fig. 2-31. Pantographic recording with the Stuart instrument. (Courtesy Drs. R. Giering and J. Petrie.)
Pantograph Device For Tmj

Fig. 2-32. Pantographic tracings represent information that could only be obtained with an infinite number of excursive records: This simplified schematic shows the relative orientation of six recording plates (attached to the maxillary bow, omitted for clarity) to the scribing styli, attached to the mandibular bow. W, Working movement; N, nonworking or balancing movement; P, protrusive movement. The CR position is represented by the intersection of the paths marked by the dot.

Fig. 2-32. Pantographic tracings represent information that could only be obtained with an infinite number of excursive records: This simplified schematic shows the relative orientation of six recording plates (attached to the maxillary bow, omitted for clarity) to the scribing styli, attached to the mandibular bow. W, Working movement; N, nonworking or balancing movement; P, protrusive movement. The CR position is represented by the intersection of the paths marked by the dot.

Mandibular Pantograph

Fig. 2-33. Electronic jaw recording system. The Axiotron is an electronic recording system that attaches to the Axiograph pantograph.

(Courtesy Great Lakes Orthodontics.)

Fig. 2-33. Electronic jaw recording system. The Axiotron is an electronic recording system that attaches to the Axiograph pantograph.

(Courtesy Great Lakes Orthodontics.)

Tmj Stereographic
Fig. 2-34. A, B, The TMJ articulator is programmed from three-dimensional acrylic resin recordings. (Courtesy Dr. A. Peregrina.)
Pantograph Articulator
Fig. 2-35. Mechanical anterior guide table. A, The protrusive path has been adjusted. The side screw adjusts the lateral flange. B, Lateral flange adjusted to the right working movement.

Stereograms (Fig. 2-34). Another approach to reproducing posterior condylar controls is to cut or mold a three-dimensional recording of the jaw movements. This "stereogram" is then used to form custom-shaped fossae for the condylar heads.

Anterior Guidance Border movements of the mandible are governed by tooth contacts and by the shape of the left and right temporomandibular joints. In patients with normal jaw relationships, the vertical and horizontal overlap of anterior teeth and the lingual concavities of the maxillary incisors are highly significant during protrusive movements. In lateral excursions, the tooth contacts normally existing between the canines are usually dominant, although the posterior teeth may also be involved (see Chapter 4). Restorative procedures that change the shape of the anterior teeth can have a profound effect on excursive tooth contacts. For this reason, when preparation of anterior teeth is contemplated, the exact nature of the anterior contacts should be transferred to the articulator, where it can be studied and stored before these teeth are prepared.

Mechanical Anterior Guidance Table (Fig. 2-35). Most articulator manufacturers supply a mechanical anterior guidance (incisal guidance) table. Such tables can be pivoted anteriorly and posteriorly to simulate protrusive guidance, and they have lateral wings that can be adjusted to approximate lateral guidance. However, the sensitivity of these adjustments is insufficient for successfully transferring the existing lingual contours of natural teeth to newly fabricated restorations. Therefore, the principal use for these mechanical tables is in the fabrication of complete dentures and occlusal devices (see Chapter 4).

Custom Acrylic Anterior Guidance Table. This simple device is used for accurately transferring to an articulator the contacts of anterior teeth when determining their influence on border movements of the mandible. Acrylic resin is used to record and preserve this information, even after the natural lingual contours of the teeth have been altered during preparation for complete coverage restorations. The technique is similar to that for stereographic recording used in setting the posterior controls of some articulators.

Custom Guide Table Fabrication

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    How much axiography® iii axiotron® axio quick® recorder?
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