Developing Posterior Contours Flashcards
Improper contours often induce early _______ of supportive structures and early ________.
Breakdown
Tooth loss
What is the crest of curvature/height of contour?
The greatest convexity on the axial surface of the crown
How does the proper crown curvature protect soft and hard tissues of the mouth?
- Will deflect food over the gingival margin and prevent irritation
- Allows stimulation of soft tissue
- Prevents tissue from being driven apically
- Maintaining gingival tone
- Preventing food/debris packing and inflammation
True or False: Excess contour is better than too little contour.
False: excess contour creates surfaces that are hidden and hard to clean
Facially, the height of contour for posterior teeth is in the ______ third.
Cervical
Lingually, the height of contour for posterior teeth is in the ______ third.
middle
What is “emergence profile”?
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
The emergence profile should be _____ for 2-3mm above the gingiva.
flat
True or False: Proximal surfaces are always flat or slightly concave between the contact area and the CEJ.
True: allows for papillae
The _______ aids in proper development of arches and prevents injury to interproximal tissues.
contact area
As age increases, the contact areas become more ______ and ______ due to functional wear.
Occlusal
broader
Contact areas of all posterior teeth should be ______ to the central fossa and in the occlusal third.
Buccal
Contact areas of posterior teeth are in the occlusal third EXCEPT for between ________ the contact is almost in the middle third.
Maxillary Molars (#3, #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.
Maxillary Molars
Distal contact areas for posterior teeth are more ______ than mesial contact areas.
cervical
Distal contact areas for posterior teeth are more ______ than mesial contact areas EXCEPT for mandibular first premolars.
cervical
Distal contact areas for posterior teeth are more ______ than mesial contact areas EXCEPT for mandibular first premolars.
cervical
Marginal ridges are rounded, elevated crests that are convex ______ and concave______.
Convex: mesiodistally
Concave: buccolingually
Marginal ridges ________ from buccal to lingual which makes the _______ half wider than the lingual.
Converge
facial
Which two teeth are wider in the lingual half than the buccal half?
Maxillary first molars
Mandibular second premolar with two lingual cusps
What is the purpose of an embrasure space?
- Spillway for the escape of food during function
2. Maintain hygiene
_______ embrasures are always larger EXCEPT for ______.
Lingual
Wide lingual teeth (mand. 2nd PM, Max. molar)
The “cervical curvature” relates to the contour of the alveolar bone so that it curves ______ at the proximal and curves ______ at the facial/lingual.
Occlusally
apically
What is the “biological width”?
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
