Developing Posterior Contours

Question 1

Improper contours often induce early _______ of supportive structures and early ________.

Answer 1

Breakdown

Tooth loss

Question 2

What is the crest of curvature/height of contour?

Answer 2

The greatest convexity on the axial surface of the crown

Question 3

How does the proper crown curvature protect soft and hard tissues of the mouth?

Answer 3

1. Will deflect food over the gingival margin and prevent irritation
2. Allows stimulation of soft tissue
3. Prevents tissue from being driven apically
4. Maintaining gingival tone
5. Preventing food/debris packing and inflammation

Question 4

True or False: Excess contour is better than too little contour.

Answer 4

False: excess contour creates surfaces that are hidden and hard to clean

Question 5

Facially, the height of contour for posterior teeth is in the ______ third.

Answer 5

Cervical

Question 6

Lingually, the height of contour for posterior teeth is in the ______ third.

Answer 6

middle

Question 7

What is “emergence profile”?

Answer 7

The profile of the gingival third of a restoration as it emerges from the gingival crevice.
aka: surface that is gingival to the HOC and above the gingival crest

Question 8

The emergence profile should be _____ for 2-3mm above the gingiva.

Answer 8

flat

Question 9

True or False: Proximal surfaces are always flat or slightly concave between the contact area and the CEJ.

Answer 9

True: allows for papillae

Question 10

The _______ aids in proper development of arches and prevents injury to interproximal tissues.

Answer 10

contact area

Question 11

As age increases, the contact areas become more ______ and ______ due to functional wear.

Answer 11

Occlusal

broader

Question 12

Contact areas of all posterior teeth should be ______ to the central fossa and in the occlusal third.

Answer 12

Buccal

Question 13

Contact areas of posterior teeth are in the occlusal third EXCEPT for between ________ the contact is almost in the middle third.

Answer 13

Maxillary Molars (#3, #14)

Question 14

Contact areas of posterior teeth are always buccal to the buccolingual center of the tooth EXCEPT between _______ the contact is in the middle third.

Answer 14

Maxillary Molars

Question 15

Distal contact areas for posterior teeth are more ______ than mesial contact areas.

Answer 15

cervical

Question 16

Distal contact areas for posterior teeth are more ______ than mesial contact areas EXCEPT for mandibular first premolars.

Answer 16

cervical

Question 17

Distal contact areas for posterior teeth are more ______ than mesial contact areas EXCEPT for mandibular first premolars.

Answer 17

cervical

Question 18

Marginal ridges are rounded, elevated crests that are convex ______ and concave______.

Answer 18

Convex: mesiodistally
Concave: buccolingually

Question 19

Marginal ridges ________ from buccal to lingual which makes the _______ half wider than the lingual.

Answer 19

Converge

facial

Question 20

Which two teeth are wider in the lingual half than the buccal half?

Answer 20

Maxillary first molars

Mandibular second premolar with two lingual cusps

Question 21

What is the purpose of an embrasure space?

Answer 21

1. Spillway for the escape of food during function

2. Maintain hygiene

Question 22

_______ embrasures are always larger EXCEPT for ______.

Answer 22

Lingual

Wide lingual teeth (mand. 2nd PM, Max. molar)

Question 23

The “cervical curvature” relates to the contour of the alveolar bone so that it curves ______ at the proximal and curves ______ at the facial/lingual.

Answer 23

Occlusally

apically

Question 24

What is the “biological width”?

Answer 24

the distance between alveolar bone and the cavosurface margin. It should be maintained at a distance between 1.5 and 2 mm to prevent bone resorption