Patient Visit 4

Clinical Procedures

Check the centric relation and vertical dimension of occlusion first.  A faulty centric relation record causes an incorrect mounting and creates the need to (1) make a new record,  (2) remount the mandibular cast, and   (3) rearrange the mandibular posterior teeth.  This is time consuming so check centric relation first.

Confirm the Vertical and Centric Relations

1. Have the mounted trial dentures checked by one of the faculty prior to the patient's appointment.

2. Wash with soap and water any prostheses received from the dental laboratory.  You are then required to disinfect the prostheses in an approved disinfectant for 10 minutes before placing the prosthesis in the patient's mouth.

3. Now, insert the wax trial dentures in the patient's mouth.  Instruct the patient not to hold the teeth firmly together during the try-in phase as this may dislodge the teeth from the wax and alter the arrangement.

4.  Holding the lower record base in place, guide the patient slowly into centric relation.  Clinical observation of the tooth contacts intraorally in centric relation will detect gross errors.  Repeat this several times until you are certain the mounting is correct or incorrect.

5. If you are not absolutely sure of the mounting's correctness, contact your faculty supervisor.  You may need to make another centric relation record to verify your mounting.
a. Apply Vaseline to the maxillary posterior teeth and place it in the patient's mouth.
b. Remove the mandibular posterior teeth and place recording material bilaterally on the posterior of the mandibular record base.
c. Place the mandibular record base in the patient's mouth and guide the patient into centric relation.
d. Remove the trial bases and centric relation record from the patient's mouth.  Place the trial bases on the master casts mounted on the articulator.  Invert the articulator and carefully position the trial bases into the new centric relation record.
e. If the ball-shaped condylar elements on the articulator do not remain seated against the posterior stop of the condylar housing during closure of the articulator when the new record is in place and the posterior teeth are properly seated in the record, then the original centric relation record is incorrect.  The mandibular cast must be removed from its mounting.  A new centric relation record is then used to remount the mandibular cast.  The mandibular posterior teeth must then be rearranged.

6. Check the vertical relation of rest and the vertical relation of occlusion.  Make sure they are satisfactory.  Apply the tests used previously to record vertical relation such as phonetics and measurement.  If the vertical relation should be increased or decreased, sometimes this change can be done directly on the articulator if the change is small (1-2 mm).  A larger change of vertical dimension will require a new centric relation record made at the new vertical dimension of occlusion.