Record Bases & Wax Rims

Question 1

record base

Answer 1

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

Question 2

Interim –

Answer 2

are discarded during denture processing

resin, Triad

Question 3

“Permanent” –

Answer 3

actually become part of the completed

denture (processed resin, metal)

Question 4

trial base

Answer 4

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 5

The Postpalatal Seal

Answer 5

the seal area at the posterior at the posterior border of a maxillary prothesis

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 in its retention

Question 6

Establishing Postpalatal seal

Answer 6

Locate vibrating line in mouth by palpating hamular notches with mirror. Have pnt say “AH” and mark area where soft palate flexes upward. Mark “vibrating line” with indelible pencil

 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)

Question 7

Record Base Fabrication (5)

Answer 7

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

Question 8

Role of Record Bases/Wax Rims (7)

Answer 8

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 9

Record bases must be: (4)

Answer 9

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

Question 9

Record bases must be: (4)

Answer 9

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

Question 10

Faulty bases contribute to the most common errors of

CD fabrication: (4)

Answer 10

 Improper Occ. Vert. Dimension
 Inaccurate centric relation registration
 Unstable “Trial Denture” (renders phonetic tests and
esthetic assessments inaccurate)
 Decreased patient confidence in dentist

Question 11

Wax Occlusion rims (2)

Answer 11

Location and dimensions are basically the same as
the natural teeth they are replacing.
 Positions of artificial teeth should be similar to those
occupied by natural teeth.

a wax form used to establish jaw relationships and to arrange artificial teeth to form the trial denture
a blueprint to assist the dentist and lab tech through the phases of denture fabrication

Question 12

purpose of wax occlusion rims (6)

Answer 12

serve as a means of transfer or face bow and 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
serve as a general aid in selection of teeth

Question 13

wax occlusion rim is an analogue for the

Answer 13

mouths neutral zone

Question 14

analogue

Answer 14

a part that is similar or comparable in some respects

Question 15

maxillary wax rim checklist (3)

Answer 15

• the labial and lingual surfaces must be smooth and free of voids
• the posterior section of the rim should be tapered to avoid the retromolar pad
• the curvature of the anterior portion must simulate the curvature of the edentulous arch

Question 16

mandibular wax rim (2)

Answer 16

• the mandibular wax rim is fabricated in a smaller manner, however, the rim should be centered over the crest of the ridge
• lingual contours must not impinge of the tongue space

Question 17

completed record bases checklist (10)

Answer 17

• palate should be consistent 1-2 mm thick and well adapted
• lingual of ridge of mandible reinforced but concave
• retromolar pad area covered
• thin areas labial to ridge
• toughened ridge areas
• no porosity or voids on tissue surface
• flanges smooth and rounded
• tissue surfaces well adapted
• no excess flash on land area of master casts
• record bases do not rock on master casts and are reasonably retentive

Question 18

campers plane

Answer 18

a line running from the inferior border of the ala of the node to some defined point on the tragus of the ear, usually considered to be the tip of the tragus. it is frequently used, with a third point on the opposing tragus, for the purpose of establishing the ala tragus plane. ideally the ala tragus plane is considered to be parallel to the occlusal plane. the occlusal plane is at an angle of approximately 10 degrees relative to the Frankfort horizontal plane, when viewed in the mid sagittal plane

Question 19

fox plane

Answer 19

used to located campers (occlusal plane) clinically

Question 20

facebow

Answer 20

orient the maxillary cast to the axis of opening/articulator