a. Appointments. Most complete denture techniques require five
appointments. On the first appointment, the patient is examined and preliminary
impressions are made. The purpose of this is to evaluate the patient and to plan
treatment. Diagnostic casts are poured from the preliminary impressions. On the
second appointment, final impressions are completed from which the master cast is
poured. The purpose of this procedure is to fabricate accurate casts upon which the
dentures will be made. On the third appointment, jaw relationship registrations are
made for transferring from the patient to the articulator all the positions and information
necessary to fabricate the dentures. On the fourth appointment, the trial denture is
evaluated in the patient's mouth and on the articulator for esthetics, occlusion, and
denture base contour. On the fifth appointment, the finished dentures are inserted into
the patient's mouth. At this time, the dentures are adjusted for fit and occlusion and the
patient is instructed in their use and maintenance and in oral health care. One or more
subsequent appointments may be given for adjustment and evaluation of the dentures.
Dental appointment systems vary from one clinic to another and can vary from one
service to another service of the same clinic. Usually, the prosthodontic section has its
own appointment system because the prosthodontist needs flexibility in determining the
time needed for each appointment and a series of appointments works out well for
prosthodontic procedures. The dental specialist must know the procedures and
routines of the particular prosthodontist. A well-planned appointment schedule can
increase the efficiency of the prosthodontic service.
b. Impressions. Impressions for complete dentures include all the teeth,
alveolar ridges, and areas of muscle attachment in a single jaw. The type of impression
material used will depend upon the purpose for which the impression is to be used, the
impression technique to be employed, and the preference of the dental officer.
Subcourse MD0502, Dental Clinical Materials, discusses the properties, uses, and
manipulation of impression materials. Examples of typical instruments and materials
used and a description of the dental specialist's duties in impression procedures follow.
Preliminary impressions are used to construct study models before fabricating complete
dentures. Final impressions are used to construct the master cast upon which the
denture is fabricated.
(1) Preliminary impressions. Irreversible hydrocolloid is the most commonly
used material for making preliminary impressions. Figure 5-10 depicts instruments and
materials used for irreversible hydrocolloid impressions.