Quiz 3 Review Flashcards
Permanent Maxillary First Molars
- Facial Aspect*
- describe facial cusp
- cuspal ridges ridges of mesiofacial
- cuspal ridges of distofacial
- facial groove extends?
1) BOTH FACIAL cusps are MORE pointed that the lingual cusps
2) Cuspal ridges of the MESlOFACIAL cusp meet at an “obtuse angle”
3) The cuspal ridges of the DISTOFACIAL cusp meet at a 90 degree angle making it sharper then the mesiofacial cusp tip
4) The FACIAL GROOVE extends occlusocervically between the mesiofacial and distofacial cusps to a point near the center of the facial surface, with a slight angulation at the facial pit location toward the distal
Permanent Maxillary First Molars
- Facial Aspect*
- unique to facial surface?
- facial ridges?
- cervical ridge runs?
1) The facial surface has a slight depression extending laterally (BOTH mesially & distally) from the cervical limit of the facial groove. This depression is occulusal to and parallel to the cervical ridge
2) The FACIAL surface has vertically facial ridges extending cervically from the cusp tip of each facial cusp, terminating in the cervical THIRD
3) CERVICAL RIDGE runs MESIODISTALLY just occlusal to the cervical line but ONLY in the MESIAL TWO-THIRDS (2/3) of the CERVICAL THIRD of the crown
Permanent Maxillary First Molars
- Facial Aspect*
- mesiofacial root extend?
- distofacial root?
- root trunk?
1) MESIOFACIAL root extends apically w/ a slight mesial curve for TWO-THRIDS of its length, the curves slightly to the distal
2) The DISTOFACIAL root is STRAIGHTER and SHORTER than the mesiofacial root
3) The root trunk AVERAGES 4 mm in LENGTH
Permanent Maxillary First Molars
- Lingual Aspect*
- distolingual cusp
- distolingual cusp tip characteristic?
- occlusal outline?
1) DISTOLINGUAL cusp is well developed and takes up the remaining 40% of the total mesiodistal width of the crown
2) The DISTOLINGUAL cusp tip is so ROUNDED that it is sometimes described as SPHEROIDAL.
- The OCCLUSAL OUTLINE of the distolinugal cusp joins the distal outline of the crown in an arc that is almost that of a semicircle.
Permanent Maxillary First Molars
- ** LingualAspect***
- lingual groove begins where?
- mesiolingual and distolingual cusps direction?
1) The LINGUAL GROOVE begins at the lingual border of the occlusal table as an extension of the distal oblique groove.
- From this origin between the MESIOLINGUAL and DISTOLINGUAL cusps, it SLANTS CERVICALLY and DIAGONALLY across the LINGUAL surface until it reaches a position near the center of the mesiodistal width of the surface, then it turns more parallel w/ the LONG AXIS of the tooth
Permanent Maxillary First Molars
- ** Mesial Aspect***
- triangular ridges of the mesiofacial & mesiolingual are ?
- mesial marginal groove crosses the ?
1) TRIANGULAR ridges of the MESIOFACIAL & MESIOLINGUAL CUSPS are not as INCLINED as on the maxillary premolars
2) There is a MESIAL MARGINAL GROOVE that crosses the mesial marginal ridge and travels slightly onto the mesial surface and is lined up with the VERTICAL LONG AXIS of the tooth
Permanent Maxillary First Molars
- ** Mesial Aspect***
- How many roots are visible?
- root truck length?
- mesial root surface shows?
1) Only 2 of the 3 ROOTS of this tooth are visible from the mesial view since the MESIOFACIAL root is much WIDER Faciolingually and slightly LONGER than the Distofacial root
2) The ROOT TRUNK is slightly SHORTER on the mesial aspect than on the facial
3) The MESIAL ROOT surface shows a “CONCAVITY” in the TRIFURCATION AREA
Permanent Maxillary First Molars
- ** Mesial Aspect***
- facial outline of the mesiofacial root often?
- describe the middle third of the root?
1) The FACIAL OUTLINE of the MESIOFACIAL ROOT often extends facially in its middle ONE-THIRD almost beyond the greatest projection of the crown
and then in the MIDDLE THIRD of the root curves LINGUALLY to a relatively blunt apex that is approximately in line w/ the tip of the mesiofacial cusp
Permanent Maxillary First Molars
- ** Distal Aspect***
- Describe the crown?
- why does the distal convergence take place?
- Is it possible to see the facial surface? explain
1) Like all Molars, the CROWN of this tooth is NARROWER in its distal half. Most of this distal convergence takes place because the facial cervical ridge flattens out in the distal half of the tooth.
It is therefore possible to see much of the facial surface when viewing the tooth from the distal aspect
Permanent Maxillary First Molars
- ** Distal Aspect***
- What extends from the cervical third of the root?
- why most clinicians be careful when restoring this tooth?
1) There is a shallow, but consistent root surface depression that extends from the CERVICAL THIRD of the ROOT across the Cervical Line onto the Cervical Third of the CROWN.
* Because this DISTAL depression is consistently seen on maxillary first molars, clinicians must be careful to restore class II preparations on this surface or be mindful of calculus deposits that may engulf the depression, making the calculus difficult to remove.
Permanent Maxillary First Molars
- ** Occlusal Aspect***
- describe cusp size
1) The cusp sizes are ordered as follows: a very large MESIOLINGUAL CUSP followed by MESIOFACIAL, DISTOLINGUAL, DISTOFACIAL and 5th (Carabelli’s) in that order. The MAXILLARY 1st MOLAR is known for having a well-developed DISTOLINGUAL CUSP
Permanent Maxillary First Molars
* Occlusal Aspect*
Describe the fossae
1) There are 2 major fossae located on either side of the mid-point of the oblique ridge. They are named the *CENTRAL fossa (in center of the occlusal surface) and the *DISTAL FOSSA ( on the distal side of the oblique ridge)
Permanent Maxillary 2nd Molars
- Facial Aspect*
- describe the facial groove
- mesiofacial cusp is?
- cervical line is?
1) The facial groove is SHORT and MORE distally positioned, especially in comparison to the maxillary 1st molar
2) MESIOFACIAL CUSP is WIDER then the distofacial cusp
3) The cervical line is STRAIGHT across from the Mesial to Distal, EXCEPT for an apical dip in the mid-point area of the crown
Permanent Maxillary 2nd Molars
- Lingual Aspect*
- mesial cuspal ridge of the mesiolingual cusp?
- distolingual cusp is ?
1) The mesial cuspal ridge of the mesiolingual cusp meets the relatively straight mesial outline of the crown at a 115 DEGREE angle
2) The DISTOLINGUAL CUSP is well developed and takes up the remaining 35 % of the total mesiodistal WIDTH of the crown
Permanent Maxillary 2nd Molars
- Mesial Aspect*
- which cusps can be seen from the mesial view?
- describe the facial and lingual outlines
- mesial marginal ridge outline displays what?
1) A portion of the 3 of the 4 CUSP TIPS can be seen from this view: MESIOFACIAL, MESIOLINGUAL, and DISTOFACIAL
2) The FACIAL and LINGUAL outlines of the crown are both CONVEX
3) The Mesial Marginal Ridge outline displays a SEMICIRCULAR CURVATURE, a devoid of a groove
