Сontouring the maxillary occlusion rim and establishing the plane of occlusion

1. Place the maxillary record base in the patient's mouth. Observe the patient's upper lip. Approximately 1-2 mm of wax should be visible in the average patient. Some patients may not show any wax at rest.

2. Mark the occlusion rim approximately 1-2 mm below the lip line. This represents the approximate length of the incisal edges of the central incisors.

3. Now, have the patient say words containing "F" and "V" sounds such as 55, 44, vivacious Vivian. The incisal edges of the maxillary central incisors should contact the inner surface of the vermilion border of the lower lip. This is also called the "wet-dry line" of the lip. If the maxillary rim does not contact the lower lip in this area, the length of the anterior portion of the rim must be adjusted by adding or removing wax. This technique is also used to evaluate the proper anterior-posterior position of the maxillary incisors. Evaluate lip support and adjust if necessary.

4. Determine the relationship of the planes of the wax rim to the interpupillary and ala-tragus planes .

Remove the maxillary record base and occlusion rim from the patient's mouth.

5. Adjust the occlusion rim to be parallel to the interpupillary and ala-tragus planes by adding or subtracting wax for the occlusion rim. A heated base spatula or pancake turner works well for this. Drip excess wax on a folded paper towel and discard to keep your work area neat.

6. Reinsert the base into the patient's mouth and recheck the occlusal plane with the landmarks. Repeat the procedure until a satisfactory plane of occlusion is established.

Vertical Relations

The physiologic rest position is the starting point from which the vertical relation

of occlusion is established for the edentulous patient. You should use as many of

the clinical methods available to determine this vertical jaw relation, for it can be a

difficult clinical procedure.

The vertical relation of occlusion represents the distance the mandible is separated from the maxilla when the denture teeth are in maximum contact. The vertical relation of rest position is a physiologic position established by muscles and gravity. The difference between the vertical relation of occlusion and the vertical relation of rest is called the interocclusal distance. The interocclusal distance is the space that exists between the denture teeth when

the mandible is at the physiologic rest position. In the edentulous patient, the amount of interocclusal distance in the existing dentures can be measured and serve as a guide when determining the amount required for this patient.

Centric relation

1. Practice guiding your patient into centric relation with the record bases in the patient's mouth. Instruct the patient place the tip of the tongue in the palate. You must hold the mandibular record base in position with your hands when making a centric relation record for complete denture patients as the mandibular record base can lift away from the patient.s tissues invalidating your records.

2. Place the occlusion rims in the patient's mouth and verify that both rims occlude evenly on closing. Adjust the rims if they do not. Close the patient into centric relation. Scribe a line on the right and left sides of the mandibular rim below the canine lines of the maxillary occlusion rim. This line will serve as a guide anteriorly when removing wax form the posterior side of the mandibular occlusion rim.

3. Remove a strip of the posterior occlusion rim approximately 1 mm in depth from the mandibular occlusion rim on both sides posterior to the marks just made. After removing the wax, cross hatch the surface of the remaining wax with the tip of a sharp knife to serve as mechanical retention for the recording medium.

4. Make two nonparallel V-shaped grooves on the right side of the maxillary occlusion rim, one in the premolar area and one in the molar area. They are located above the cross-hatched surfaces of the mandibular occlusion rim. These grooves should not be more than 2 mm in depth. Repeat on the left side of the maxillary occlusion rim.

5 Place the maxillary record base in the patient's mouth and check it for retention and stability. If it is unstable or nonretentive, a small amount of denture adhesive may be necessary.

6. A wax or a metallic oxide registration paste (Kerr Bite Registration Paste) can be used as a recording medium.

7. Place a small amount of material on the mandibular occlusion rim in the area of the premolars and molars. Carefully place the record base in the patient's mouth and slowly guide the patient into centric relation. Hold the mandibular record place in position with your index fingers when guiding the patient into centric relation.

The centric relation record is valid only at the established vertical relation of occlusion. Your record of the vertical relation of occlusion is preserved in the anterior portions of the wax rims. Take care to note that wax rims are contacting anteriorly when you make your centric relation record.

8. After the recording medium has set, remove the record base from the patient's mouth and inspect it.

Scribing

Scribe the midline on the maxillary rim at this time to represent the location of the central incisors. The patient can assist by holding the bottom of a piece of dental floss while you hold the top in the center of the forehead. Next, scribe the high lip line (Line of smile) perpendicular to the midline as the patient smiles his or her widest. Scribe the right and left canine lines at the corners of the mouth when at rest. Dental floss can aid you in marking the canine lines.

Materials for self-control:

A. Tests for self-control (tables, diagrams, drawings, graphs)

Task for self-control:

Draw a diagram of the structure of clinical examination methods.

Date: 2015-12-24; view: 1905