Quiz 4 Review Flashcards
Permanent Mandibular First Molar
- Facial Aspect*
- Where do the cuspal ridges of the mesiofacial cusp meet?
- The distofacial cusp has ridges that?
- The distal cusp comprises? And it is more ?
1) The CUSPAL ridges of the MESIOFACIAL CUSP meet at an ANGLE that is almost FLAT
2) The DISTOFACIAL cusp has cuspal ridges that give RISE to more POINTED CUSP tip than the mesiofacial cusp, but the cusp tip is still ROUNDED
3) The DISTAL CUSP comprises a SMALL part of the total mesiodistal width of the facial surface because MOST of the CUSP is LINGUAL to the “distofacial line angle” placing it on the distal aspect of the tooth.
* *** The DISTAL cusp tip is MORE POINTED than either the mesiofacial or distofacial cusp
Permanent Mandibular First Molar
Facial Aspect
- The mesiofacial groove is what than the distofacial groove?
- What does it end in?
- Where is the pit (what is it called)?
1) The MESIOFACIAL groove is SHORTER than the distofacial groove and EXTENDS from the OCCLUSAL margin of the FACIAL surface and terminates HALF way to the cervical line, ENDING in a slight DEPRESSION that EXTENDS LATERALLY from the terminus of the groove.
2) There is a PIT present at the TERMINUS that commonly requires RESTORATION that is termed a “facial” or “buccal” pit
Permanent Mandibular 1st Molar
- Facial Aspect*
- How much does the root trunk on facial aspect measure to be on average?
- Where is the deep depression ?
- Where are the 2 roots positioned?
1) The ROOT trunk on the FACIAL aspect measures 3.0 mm on the AVERAGE.
There is a DEEP DEPRESSION between the ROOTS that becomes more shallow as it extends occlusally from the BIFURCAITON to the CERVICAL line, but DOES NOT CROSS the cervical line.
2) TWO ROOTS are positioned MESIALLY and DISTALLY. The ROOTS of the mandibular 1st molar are usually LONGER and MORE DIVERGENT than those of the mandibular 2nd OR 3rd molar.
Permanent Mandibular 1st Molar
- Lingual Aspect*
- The cervical line is positioned where?
- What is the root trunk measurement? (What is average)
- Total root length will be?
1) The CERVICAL LINE is positioned approx. 1.0 mm HIGHER on the LINGUAL SURFACE than on the facial surface so the ROOT trunk measurement will also be 1.0 mm LONGER (average 4.0 mm) from cervical line to bifurcation on the LINGUAL ASPECT of the tooth
2) When measured on the LiNGUAL, the TOTAL root LENGTH is GREATER because of the roots are measured from the CERVICAL LINE to the APEX.
Permanent Mandibular 1st Molar
- Mesial Aspect*
- What is the shape of crown?
- Where is the greatest curvature?
- Where is the crest higher?
1) The MESIAL crown outline is RHOMBOIDAL shaped
2) The GREATEST CURVATURE of the facial outline is at the CERVICAL THIRD of the crown and is termed the cervical ridge.
3) The crest is HIGHER OCCLUSALLY when compared to the cervical ridges found on maxillary molars bit is still in the CERVICAL THIRD
Permanent Mandibular 1st Molar
- Mesial Aspect*
- What is the angulation of the triangular ridge of the mesiolingual cusp?
- Mesial cusps are?
1) The ANGULATION of the triangular ridge of the MESIOLINGUAL cusp is approx. 30 DEGREES in relation to the “mesial marginal ridge”.
2) Since the MESIAL CUSPS are TALLER than the distal cusps on the tooth, very little of the occlusal surface can be viewed.
Permanent Mandibular 1st Molar
- Distal Aspect*
- The facial outline of the distal cusp is located? (what happens to the distal cusp?)
- What does the distal cusp comprise of?
- What is this also slightly facial to?
1) The FACIAL outline of the DISTAL cusp is located LINGUALLY to the facial outline of the TALLER DISTOFACIAL cusp with entire DISTAL cusp superimposed onto the distofacial cusp
2) The DISTAL CUSP exclusively comprises the DISTAL CONTACT AREA, which is also slightly FACIAL to the faciolingual vertical bisector of the crown
Permanent Mandibular 1st Molar
- DISTAL Aspect*
- The distal and distofacial cusps re what?
1) BOTH the DISTAL and the DISTOFACIAL CUSP Tips are FACIAL to the APICES of the MESIAL and DISTAL ROOTS
Permanent Mandibular 1st Molar
- Occlusal Aspect*
- The distofacial cusp is most _________ placed where the mesiolingual cusp is the most___________?
1) The DISTOFACIAL CUSP is MOST facially placed and the MESIOLINGUAL cusp is the MOST MESIALLY placed cusp on the tooth
Permanent Mandibular 1st Molar
- Occlusal Aspect*
- What is the cusp sizes? (L–>S)
Cusp sizes from LARGEST to SMALLEST are:
1 ) MESlOFACIAL 2) MESIOLINGUAL 3) DISTOLINGUAL 4) DISTOFACIAL 5) DISTAL CUSP
Permanent Mandibular 2ND Molar
- Facial Aspect*
- What is the facial groove called?
- What does it divide?
1) There is ONE FACIAL GROOVE called the FACIAL (or “BUCCAL”) Groove & it divides the MESIOFACIAL and DISTOFACIAL CUSPS, ending in a distinct FACIAL (BUCCAL) pit in the MIDDLE THIRD of the CROWN
Permanent Mandibular 2ND Molar
- Facial Aspect*
- The facial groove is what? (exception?)
- Where is the mesial inclination located?
1) The FACIAL groove is VERTICAL, EXCEPT for a SLIGHT MESIAL INCLINATION at the Facial Pit & is located slightly DISTAL to the VERTICAL LINE dividing the crown in half, MESIODISTALLY
Permanent Mandibular 2ND Molar
- MESIAL Aspect*
- Where is the tip of the mesiofacial cusp closer to?
1) The TIP of the MESIOFACIAL CUSP is CLOSER to the VETICAL FACIOLINGUAL Long Axis Bisector than to the greatest facial outline of the crown
Permanent Mandibular 2ND Molar
- Occlusal Aspect*
- Where are the tips of both the facial cusps located?
1) The TIPS of BOTH FACIAL CUSPS, especially the MESIOFACIAL cusp, are located FARTHER LINGUALLY from the facial outline of the crown than the tips of the lingual cups in relation to the “lingual outline”.
Permanent Mandibular 2ND Molar
- Occlusal Aspect*
- Where does the Facial groove & Lingual groove meet?
- What does these 3 grooves present ?
- The Central pit forms where?
1) The FACIAL GROOVE & LINGUAL GROOVE MEET the CENTRAL GROOVE @ RIGHT ANGLES dividing the occlusal surface into MESIAL and DISTAL halves.
2) These 3 MAJOR GROOVES present a structure which is to be a “+” or “cross” design, or even a 4+ arrangement because there are 4 CUSPS of approx. equal size with a “+” sign dividing them
3) The CENTRAL PIT forms where the FACIAL, LINGUAL, and CENTRAL GROOVES meet and is LOCATED on the lingual half of the crown
