1/22: Posterior Palatal Seal; Record Bases; Facebow transfer

Question 1

What is the average distance between the upper and lower labial sulci adjacent to the labial frenula when teeth are in occlusion?

Answer 1

40 mm

Question 2

The distance from the upper sulcus to the incisal edge of the upper central incisor is an average of

Answer 2

22 mm

Question 3

the distance from the lower sulcus to the incisal edge of the lower central incisor is an average of

Answer 3

18 mm

Question 4

What is a record base?

Answer 4

An interim denture base used to support the record rim material for recording maxillomandibular records.

Question 5

What does interim mean?

Answer 5

Discarded during denture processing (resin, triad)

Question 6

What does permanent mean?

Answer 6

Actually become part of the completed denture (processed resin, metal)

Question 7

What is a trial base?

Answer 7

A material or device representing the base of a denture
- It is used for making maxillomandibular relationship records and for the arrangement of teeth

Question 8

What is the postpalatal seal?

Answer 8

The soft tissue area at or beyond the junction of the hard and soft palates on which pressure, within physiologic limits, can be applied by a denture to aid its retention

Question 9

Where is the posterior palatal seal?

Answer 9

Posterior border of a maxillary prosthesis

Question 10

How do you establish the posterior palatal seal?

Answer 10

• Saying “ah” makes the soft palate go up
• Pinching the nose and trying to blow through it makes the soft palate go down (Valsalva maneuver)
• Transfer the marked posterior palatal seal line from the mouth to the final impression

Question 11

When should you carve the transferred posterior palatal seal into the master case?

Answer 11

Before making the record base

Question 12

What is the record base fabrication?

Answer 12

• Autopolymerized resin: sprinkle-on
• Visible-light-cured material
• Vacuum-formed
• Heat-processed resin
• Cast metal

Question 13

What is the role of record bases/wax rims?

Answer 13

• Establish Rest Vertical Dimension
• Establish Occlusal Vertical Dimension
• Establish adequate interocc. Distance
• Establish tentative occlusal plane
• Determine & record centric relation
• Transfer jaw relationship to articulator
• Enable “Trial denture” arrangement

Question 14

Record bases must be:

Answer 14

• Rigid
• Stable
• Smooth, contoured, comfortable
• Accurately fitting for retention & stability

Question 15

What contributes to the most common errors of CD fabrication?

Answer 15

Faulty bases

Question 16

What does the wax occ. rim establish?

Answer 16

Jaw relationships and to arrange artificial teeth to form the “trial denture”

Question 17

What is the purpose of wax occlusion rims?

Answer 17

Serve as a means of transfer of face bow transfer records
Aid in orientation of the incisors and the occlusal plane when properly contoured
Aid in developing contours of the lips and cheek when properly contoured
Used in developing the vertical dimension of occlusion
Used in making tentative centric relation records
Sere as a general ad in selection of teeth

Question 18

According to Zarbs text, what is a wax occlusion rim known as?

Answer 18

“An analogue for the mouth’s neutral zone”

Question 19

What does analogue mean?

Answer 19

A part that is similar or comparable in some respects

Question 20

What is a camper’s plane?

Answer 20

A plane established by the inferior border of the ala of the nose

Question 21

What does the facebow orient?

Answer 21

Maxillary case to the axis of opening/articulator