WAX PATTERN

Question 1

Steps of wax pattern fabrication

Answer 1

1-Coping fabrication
2-Axial contouring
3-Waxing of occlusal morphology 4-Margin adaptation and finishing 5-Evaluation, finishing, and polishing

Question 2

Emergence profile

Answer 2

The part of the axial contour that extends from the base of the gingival sulcus To the height of contour, the emergence profile should be straight or concave To facilitate access for oral hygiene

Question 3

The two principal objectives of Margin finishing

Answer 3

(1) minimizing dissolution of the luting agent and (2) facilitating plaque control.

Question 4

defects may happen during fabrication of cast restoration At the margins

Answer 4

include :
1-over-hanging margins (thick margin)
2-over-extended margins
3-under-extended margins
4-open margins

Question 5

the wax pattern will be….

Answer 5

duplicated exactly through The investing and casting technique, the final restoration will be exactly as the Wax pattern

Question 6

There are two accepted ways of fabricating a wax pattern:

Answer 6

1-The direct technique, in which the pattern is waxed on the prepared tooth in The mouth
2-The indirect technique, in which the pattern is waxed on a stone cast made From an accurate impression of the prepared tooth

Question 7

Types of wax used in wax pattern construction

Answer 7

Type 1-for intra oral patterns, inlays, post& core

Type2-for extra oral pattern construction , cases of crown & Bridge

Question 8

Requirement of inlay wax include :

Answer 8

1- should be of different color than that of the die
2-should flow readily when heated
3-should be rigid when cooled

Question 9

Consistency of type II inlay wax :

Answer 9

1-soft inlay wax
Used in fabrication of initial layer of wax pattern (coping fabrication)

2-medium consistency inlay wax
ed in build up of the bulk of the wax pattern contour

3-hard consistency inlay wax
Used at the margin to prevent any wax distortion at the margin

Question 10

Steps of wax pattern fabrication

Answer 10

1-Coping fabrication
2-Axial contouring
3-Waxing of occlusal morphology
4-Margin adaptation and finishing
5-Evaluation, finishing, and polishing

Question 11

Methods of coping fabrication

Answer 11

1-Dipping method
2-Addition method
3-Molten press method

Question 12

should be observed during waxing of axial surfaces

Answer 12

1-Contact area
2-Hight of contour
3-Embrasures
4-Emergence profile

Question 13

The location and size of contact area should be determined in wax pattern, meaning ?

Answer 13

Occluso- gingivally most posterior contact areas are located in the occlusal third Of the crown except for the contact between the maxillary first and second molar which located In the middle third

Facio-lingually most posterior teeth contacts are located slightly to the facial Aspect of the middle of the posterior teeth except for the contact between The maxillary first and second molars which are centrally located.

Question 14

A pinpoint contact may cause

Answer 14

food impaction between

Question 15

Too large contacts can

Answer 15

encroach on gingival embrasure Which make plaque control very difficult and lead to Periodontal disease

Question 16

Height of contour on the facial surface of posterior teeth on

Answer 16

the cervical third

Question 17

Height of contour on the lingual surface on the

Answer 17

middle third ,except in the Maxillary premolar and molar in the cervical third

Question 18

Amount of height of contour on the buccal and lingual surface

Answer 18

facial contours , 0.5mm beyond the out line of root at CEJ

lingual surfaces , 0.5mm on all maxillary posterior teeth and Mandibular first premolar, about 0.7mm on mandibular second premolar and 0.1mm on mandibular molars.

Question 19

In the Negative waxing technique

Answer 19

Bring the Working and opposing casts together

Question 20

WAX-Added technique also called

Answer 20

(positive waxing technique) + occlusal features like cusp tips (called cones)

Question 21

In requirements of properly waxed occlusal surfaces, The cusps and ridges of occlusal surfaces should be………Without……..

Answer 21

shaped to allow even contact With opposing teeth , interferences in centric and eccentric

Question 22

During wax pattern fabrication in centric occlusion position should be three Point contacts (ABC) which are

Answer 22

A-contacts: between lower buccal and upper buccal cusps
B-contacts: between lower buccal and upper palatal cusps
C-contacts: between the lower lingual and upper palatal cusps

• B-contacts are the most important

Question 23

Depending on the position of contacts there are two types of occlusal arrangement

Answer 23

1-cusp-marginal ridge occlusion
2-cusp-fossa occlusion

Question 24

During cut back of wax patterns for metal-ceramic restorations, the exact amount Of space required for porcelain can be determined using either of two methods:

Answer 24

1-Use of depth orientation grooves
2-Use of putty index