4.3 Technology of acrylic partial denture

what are impression trays?

1. receptacle into which suitable impression material is placed to make a negative likeness

2. Device that is used to carry, confine and control impression material while making an impression

what materials can be used for individual tray fabrication?

• shellac base plates

• photocured base plate

• acrylic resin

what is occlusion/occlusal rim?

• occluding surfaces fabricated on interim or final denture bases for purpose of making maxillo mandibular relation records and arranging teeth (also called record rim)

factors to consider when choosing between complete and removable partial dentures

1. any splinting needed

2. distribution - symmetrical or not

3. functional expectation

4. strong patient desire to maintain teeth

what is wax rim?

• prismatic bodies made of pink wax with a cross section of 1cm

• prefabricated

• laboratory made

• elliptical ( for maxilla), parabolic (for mandible)

In artificial teeth setup the occlusal rim should provide?

• guidelines: midline, high hipline + canine lines

• proper placement of occlusal plane

• proper lip support

• correct jaw relationship

Bonvill triangle

• equilateral triangle measuring 4 inches (above 11 cm)

• triangle is formed by connecting contact points of mandibular central incisors’ incisal edge to each condyle midpoint

• First described triangle in 1858

• Triangle is based on principle of geometry, mathematics and mechanics in scientific articulation of human teeth

Factors to look out for during fixation in occludator?

• High lip line, canine line and midline are marked on

• In all movements, centric relation, intercuspal position between upper and lower teeth there is occlusal contact (make sure balanced occlusion is occurring) (only for complete dentures)

• Need use of facebow, instrument that will allow us to take facebow registration of patient and to fix the models in the articulator