Facial Prosthetics Design & Fabrication Flashcards

When using a craniofacial implant system to retain an auricular prosthesis, the abutment height is selected primarily based on:

Answer: Soft tissue thickness at the implant site

Abutment height must match soft tissue thickness so the prosthesis bar seats flush without compressing or tenting tissue.

A color metamerism problem occurs when a prosthesis appears well-matched in the clinic but mismatches in outdoor light. This is corrected by:

Answer: Checking and adjusting color match under multiple light sources during fabrication

Metameric matches fail under different illuminants; evaluating and adjusting color under daylight, incandescent, and fluorescent light during fabrication prevents this.

Which material property is described by the ability of a silicone prosthesis to return to its original shape after deformation?

Answer: Resilience / elastic recovery

Resilience (elastic recovery) describes how completely a material rebounds after stress is removed, critical for prostheses that flex with facial movement.

During impression-making for an orbital prosthesis, the patient should ideally maintain which gaze direction?

Answer: Straight-ahead primary gaze

Primary gaze represents the functional position and ensures the prosthetic eye will be correctly oriented for everyday use.

When fabricating a prosthetic ear for a child with microtia who is still growing, the preferred retention strategy is:

Answer: Adhesive retention with plans to replace the prosthesis as growth occurs

In growing children, adhesive retention is preferred because osseointegrated implants should be deferred until craniofacial growth is complete.

The purpose of applying a mold release agent (separator) before investing in dental stone is to:

Answer: Allow separation of mold sections without damaging the model or prosthesis

A separator prevents chemical bonding and mechanical interlocking between stone layers, enabling clean mold separation.

A two-part flasking technique for an auricular prosthesis uses a 'cope' and 'drag.' The drag refers to:

Answer: The lower base section of the flask

In foundry and dental flask terminology, the drag is the lower mold half and the cope is the upper half.