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The function of this molar is similar to that of all molars in regard to grinding being the principle action during mastication, commonly known as chewing.
Function
What are the teeth precede the mandibular molars? It is important to note that the permanent mandibular molars are not considered to have any teeth that precede it.
General characters of the Permanent Mandibular first Molar:2. General form and function:
It is the largest and strongest tooth in the lower arch. It normally exhibits five functional cusps, and two well developed roots. The crown is the greatest mesiodistal dimension than that of any tooth in the mouth. From the occlusal, the general outline is pentagonal. In mastication, it functions with the other molars in grinding.
General characters of the Permanent Mandibular first Molar:3. Chronology:• Appearance of dental organ:
•1st. Evidence of calcification:
• Crown completed:
• Eruption:
• Root completion:
4 m.i.u.l.
At birth
2½ - 3 years.
6 - 7 years.
9 - 10 years.
MorphologyBuccal Aspect:
( Facial Aspect )I ) Crown:
1. Geometric outline.
2. Surface outlines:
- Mesial outline: ( including contact area )
- Distal outline: ( including contact area )
- Cervical outline.
- Occlusal outline.
3. Surface describtion:
II) Root: 1. Root trunck. 2. Mesial root (mesial & distal
outlines, apex) 3. Distal root: (mesial & distal
outlines, apex)
⅓
⅓
⅓½
½
MorphologyLingual Aspect: I ) Crown:
1. Geometric outline:
2. Surface outlines:
- Mesial outline: ( including contact area )
- Distal outline: ( including contact area )
- Cervical outline:
- Occlusal outline:
3. Surface describtion:
II) Root: 1. Root trunck. 2. Mesial root (mesial & distal
outlines, apex) 3. Distal root: (mesial & distal
outlines, apex)
MorphologyMesial Aspect:
( Proximal Aspect )I ) Crown:
1. Geometric outline:
2. Surface outlines:
- Buccal outline: ( including crest of curvature )
- Lingual outline: ( including crest of curvature )
- Cervical outline:
- Occlusal outline.
3. Surface describtion.
II) Root: 1. Buccal outline. 2. Lingual outline. 3. Apex. 4. Surface describtion.
⅓
⅓
⅓
MorphologyDistal Aspect:
( Proximal Aspect )I ) Crown:
1. Geometric outline:
2. Surface outlines:
- Buccal outline ( including crest of curvature )
- Lingual outline ( including crest of curvature )
- Cervical outline.
- Occlusal outline.
3. Surface describtion.
II) Root: 1. Buccal outline. 2. Lingual outline. 3. Apex. 4. Surface describtion.
MorphologyOcclusal Aspect: 1. geometric outline:
2. dimensions.
3. surface outlines:
- Buccal outline.
- Lingual outline.
- Mesial outline.
- Distal outline
4. surface describtion:
- cusps.
- grooves.
- fossae.
1
2 2
34
MAXILLARY FIRST MOLARIt is the largest tooth in the maxillary arch.
Principal identifying features1- Rhomboidal occlusal outline.2- BL measurement>MD 3- Four cusps and the cusp of carabelli (non
functional cusp), on the lingual surface of the mesiolingual cusp.
4- There is an oblique ridge between the mesiolingual and distobuccal cusps.
5- Three well separated and well developed roots. The lingual root is the longest.
6-Mesial surface.