Premolars Flashcards
How many premolar are there per quadrant?
2
How many premolars are there in total?
8
What is an alternative name for premolars?
Bicuspids
How many cusps do premolars have?
2
one buccal, one lingual; mandibular 2nd can have 2 lingual
Which cusp in a premolar is larger?
Buccal cusp
How many lobes are found in premolars?
4 lobes
What ridges are found in premolars?
Cusp ridge
transverse ridge
Marginal ridge
How many grooves are seen in premolars?
3 (mesiobuccal, distobuccal, central)
What shape is the crown of premolars?
Pentagonal (from buccal)
Trapezoidal (from proximal)
The ___ contacts of premolars are GENERALLY higher than the ___ contacts.
Mesial (near junction of occlusal and middle thirds)
Distal (more cervical in middle third)
Which proximal contacts are GENERALLY higher in premolars?
Mesial
Which premolar is the exception to the proximal contact general trait?
Mandibular 1st premolar (mesial contact is more cervical /same level as distal contact)
In the mandibular 1st premolar, the mesial proximal contact is ___ compared to the distal proximal contact.
More cervical / same level
In the maxillary 1st premolar, the mesial proximal contact is ___ compared to the distal proximal contact.
More occlusal (higher)
All premolar crowns taper towards the ___ from the contact area.
Lingual
What is the function of the buccal and lingual contours of premolars?
Deflect food away from gingival margin (self-cleaning mechanism)
Where is the buccal height of contour for premolars?
Cervical 1/3
Where is the lingual height of contour for premolars?
Middle 1/3
Occlusal 1/3 in mandibular 1st
The lingual cusp tip of all premolars is ___ to midroot axis.
Mesial
Generally, the ___ marginal ridge of premolars is more occlusal than the ___ marginal ridge. Why?
Mesial, distal
Crown tapers from mesial to distal
Exception: mandibular 1st premolar (distal more occlusal)
The distal marginal ridge is more occlusal for the ___ premolar.
Mandibular first
For all premolars, The apical third of roots bends ___ more often than ___.
Distally, mesially
For all premolars, cervical lines curve ___ on facial / lingual surfaces and curve ___ on proximal surfaces.
Apically, occlusally
The ___ cervical line is more convex than the ___ for all premolars.
Mesial, distal
Do the anteriors or premolars have a taller crown?
Anteriors
Do anteriors or premolars have more curvature of cervical line on mesial and distal?
Anteriors
Do anteriors or premolars have broader contact areas?
Premolars
Do anteriors or premolars have contact areas more nearly at the same level?
Premolars
Are anteriors or premolars wider bucco-lingually than mesio-distally?
Premolars