Dental Anatomy V - Quiz 4 Flashcards
Name the Facial Cusps of the Mandibular 1st Molar?
Mesiofacial
Distofacial
Distal
Describe the Facial Cusps of the Mandibular 1st Molar
Mesiofacial - Almost Flat
Distofacial - 90 degrees, More Pointed than MF
Distal - very small, Lingual, more pointed than MF or DF
Describe the MF cusp of the Mdb1M
Almost flat
Describe the DF cusp of the Mdb1M
90 degrees
More pointed than MF
Describe the Distal cusp of the Mdb1M
3 things
Small
Lingual
More pointed than MF or DF
T/F
There is no Facial groove in the Mdb1M
False
- Two of them
- Mesiofacial groove
- Distofacial groove
Which groove is shorter, the Mesiofacial or Distofacial groove of the Mdb1M?
Mesiofacial
The Mesiofacial groove of the Mdb1M extends from the ______ to the ______.
Occlusal
Halfway to Cervical Line
What is at the end of the MF groove of the Mdb1M?
Slight lateral depression
How long is the Root Trunk in the Facial aspect of the Mdb1M?
3mm
Describe the Depression on the facial aspect of the Mdb1M
3 points
Deep
progressively Shallow occlusally
Does NOT cross cervical line
How are the 2 roots of the Mdb1M positioned from the Facial aspect?
Mesially
Distally
How do the roots of the Mdb1M compare to the roots of the Mdb2M?
(2 points)
Longer
More divergent
Which root length is greater in the Mdb1M, the Facial or Lingual aspect?
Why?
Lingual
Cervical line has moved occlusally 1mm on the Lingual side
Where is the Cervical Line higher in the Mdb1M, Lingual or Facial?
By how much?
Lingual
1mm
making root length 4mm
From the mesial aspect of the Mdb1M, what shap is the crown outline?
Rhomboidal
Mesial aspect Mdb1M: The Crest of Contour of the Cervical Ridge is _______ than MaxM’s, but _______.
Higher Occlusally
Still in Cervical 1/3
Mdb1M - Mesial Aspect
What is the angle between the Triangular Ridge of the ML cusp and the Mesial Marginal Ridge?
30 Degrees
Why can very little occlusal surface be seen from the Mesial Aspect of the Mdb1M?
Mesial cusps Taller
Mdb1M - Distal Aspect
The facial outline of the Distal Cusp is _____ to the facial outline of the taller _____ cusp
Lingual
Distofacial
From the Distal Aspect Mdb1M, what is superimposed onto the Distofacial Cusp?
Entire Distal Cusp
What EXCLUSIVELY makes up the distal contact area of the Mdb1M?
Where is this located in relation to the faciolingual bisector of the crown?
Distal Cusp
```
Slightly Facial
definitely NOT lined up
~~~
Mdb1M - Distal Aspect
Both the distal and distofacial cusp tips are _____ to the apices of the mesial and distal roots.
Facial
What is the most Facially placed cusp in the Mdb1M?
Distofacial cusp
What is the most Distally placed cusp in the Mdb1M?
Distal cusp
What is the most Mesially placed cusp in the Mdb1M?
Mesiolingual cusp
What are the cusp sizes of the Mdb1M from largest to smallest?
Mesiofacial Mesiolingual Distolingual Distofacial Distal
Mdb2M - Facial Aspect
How many facial grooves?
What does it divide?
Where does it end?
One
Mesiofacial and Distofacial cusps
Distinct pit in Middle 1/3 of crown
What are the 2 pieces of Negative Anatomy on the Facial Aspect of the Mdb2M?
Facial Groove
Facial Pit (middle 1/3)
Describe the path and location of the facial groove in the Mdb2M
path: slight Mesial bend toward Facial Pit
location: slightly Distal to vertical line dividing line in half
Mdb2M
Mesiofacial cusp is located closer to:
Vertical faciolingual long axis bisector, or
Facial outline
Vertical faciolingual long axis bisector
Mb2M - Occlusal View
Which set of cusps is offset further from their respective outlines?
What 1 cusp in particular?
Facial Cusps
Mesiofacial cusp especially
Describe the Lingual cusps of the Mb2M
Not as offset as far from Lingual outline as Facial cusps are offset from Facial outline
What divides the Occlusal surface of the Mb2M into halves?
Central Groove
What meets at right angles at the Central Groove of the Mb2M?
(these are the 3 major grooves)
Facial groove
Lingual groove
Central groove
What do the facial, lingual, and central grooves of the Mb2M make?
What does this delineate?
cross design
4 cusps approximately equal size
To what side is the central pit of the Mb2M offset?
Lingually
*forms from facial, lingual, central grooves
Where do the lateral ends of the central groove end in the Mb2M?
Mesial and Distal Triangular fossae
T/F
The Mesial and Distal Triangular fossae of the Mb2M each have a triangular Pit
True
Each of the 4 cusps of the Mb2M have 3 features.
What are they?
Mesial and Distal Cuspal Ridges
Triangular Ridge
The Triangular Ridges of the Mb2M form what?
2 Transverse Ridges
What feature of the Mb3M often exhibits decay because it is difficult to clean?
Where is it located?
Facial Pit
Middle 1/3 Facial aspect
Mb3M - Mesial aspect
Where is the Central Groove located?
Lingual to faciolingual long axis bisector
Mb3M - Occlusal
What direction is wider?
Mesiodistal wider than faciolingual
just like other molars
