Wax try in

Question 1

What needs to be checked at try-in stage?

Answer 1

Aesthetics
OVD
Occlusion in relation to ICP and RCP
Border extensions
Border thickness
Neutral zone issues
Tongue space
Mark post dam and lower border extensions

Question 2

Significant other

Answer 2

Get them to come to next apt. to ease impressions

Question 3

Occlusal balance

Answer 3

To allow maintenance of occlusal balance in antero-posterior and lateral mandibular excursions
Compensation curves: antero-posterior curve, lateral curve

Question 4

Balanced occlusion

Answer 4

First point of contact when px occcludes in centric relation (static position)
As many teeth as possible should contact evenly in this position
ICP must = RCP

Question 5

Balanced articulation (movement)

Answer 5

Desirable to have multiple contacts on both sides of denture in lateral and protrusive movements - stops dentures from tipping
Opposite for dentate pxs

Question 6

Dental appearance

Answer 6

Tooth characteristics

Soft tissue relationships

Question 7

Tooth characteristics

Answer 7

Arrangement: rotation, spacing
Shade: overall, local
Shape: overall, local

Question 8

Midline diastema

Answer 8

Gap

Question 9

Tooth shape - overall

Answer 9

For harmony, tooth shape should correspond to inverse of face shape

Question 10

Tooth shape - local

Answer 10

‘Attrition’ especially when associated with an angular, tapering mould gives ‘masculine’ appearance

Question 11

Soft tissue relationships

Answer 11

Visibility
Support
Tooth/ lip harmony

Question 12

How much tooth should be visible

Answer 12

More lax musculature of older px makes it difficult to reproduce extensive tooth exposure of young px
Let pxs show between 1/2 and 2/3 of incisors
Difficult to get acrylic to match gum colour (ask technician to add contouring and stippling)

Question 13

Tooth/ lip harmony

Answer 13

Lines of lower lip and incisors coincide = harmony
Lines of lower lip and incisors do not coincide = disharmony
Some pxs have irregular lip line

Question 14

Clinical technique

Answer 14

Equipment/ procedure

Correction

Question 15

Error in vertical jaw relations

Answer 15

If small, can make changes at articulator pin and request re-try

Question 16

Error in antero-posterior relations

Answer 16

Take teeth of try in from lower back

Question 17

RCP must = RCP

Answer 17

Take firm control of lower jaw

Index fingers bucccal to lower 4 5 6 region and thumbs under chin

Question 18

Overextension

Answer 18

Check traction

Question 19

Why is mapping post dam the key to retention

Answer 19

Cannot be left to technicican - they have no idea of compressibility of mouth
Every px is different & compressibility diff. in diff areas
Inadequate post dam will lead to poor posterior seal

Question 20

Marking post dam

Answer 20

Get px to say aaah
See where vibrating line is
Mark posterior border with indelible pencil
Palpate anteriorly to this with ball/ pear burnisher to see which tissues are compressible
Consider marking more than one post dam if retching or poor tolerance expected
Ask lab to keep acrylic between two post dams as thin as possible
Then transfer onto master cast

Question 21

Distal margin of maxillary denture

Answer 21

Should be sited 1-2mm anterior to fovae palatini

Question 22

Cutting post dam

Answer 22

Ash 3 - 693

Scribe to required depth with Ash knife or with large bur in straight handpiece

Question 23

Markings that may be useful

Answer 23

Post dam
Retromolar extensions
Width of frenal relief
Buccal extensions around external oblique regions