tooth anatomy Flashcards
upper central incisor
Larger than upper lateral incisor
- Mesioincisal angle is sharp and the distoincisal angle is rounded
- Incisal edge is straight
- Cingulum is centralised
- Conical and round root
upper lateral incisor
Incisal edge is sloping distally
- Cingulum is twisted distally
- Root apex curved distally
- Presence of palatal pit
- Both incisal angles are rounded
lower central incisor
Most symmetrical teeth
- Smallest teeth in the oral cavity
- Lingually inclined
- Incisal edge and cingulum – centralised
- Mesioincisal and distoincisal angles are sharp
lower lateral insisor
Larger than lower central incisor
- Has sharp mesioincisal angle and round distoincisal angle
- Incisal edge sloping distally
- Cingulum twisted distally
- Root apex curved distally
upper canine
The Crown is shorter and broader
- Lingual ridge is very prominent
- The lingual ridge runs from the cusp tip to the cingulum – divides lingual
fossae into two
- Longest root in the oral cavity
- Cusp tip is pointed
- The mesial cusp slope is shorter than the distal cusp slope
- Root is curved distally
lower canine
Crown is longer and narrower
- Lingual ridge is present only on the incisal third
- Crown is lingually inclined
- Cusp tip is less pointed than the upper canine
- Mesial cusp slope is shorter than distal cusp slope
- Root is shorter than upper canine
- Root is curved distally
upper first pre-molar
Two cusps present – lingual cusp is shorter than buccal cusp by 1 mm
- Mesial slope of the buccal cusp is slightly longer than the distal slope.
- Canine fossae present on mesial surface
- MMDG (Mesial marginal developmental groove) is present on the mesial
surface
- Occlusal surface – hexagonal in shape
- Longer central developmental groove
- Usually, two roots are present
upper second pre-molar
No canine fossa
- NO MMDG
- Distal surface of the buccal cusp is longer than mesial slope
- Occlusal surface – oval in shape
- Buccal and lingual cusp similar length
- Short central developmental groove
- Presence of supplementary grooves
- Mostly single root
lower first pre-molar
Severe lingual inclination
- Severe lingual convergence
- Occlusal outline – diamond
- Snake eyes appearance – occlusal surface
- MLDG (mesiolingual developmental groove) is present
lower second pre-molar
can have 2 or 3 cusps.
Occlusal surface – 2 cusp type
- Oval shaped
- Has lingual convergence
- U-shaped or H-shaped CDG
- Supplementary groove present
Occlusal surface – 3 cusp type
- Square shaped
- No lingual inclination and no lingual convergence
- Y-shaped CDG
- One buccal cusp and two lingual cusp – one large mesiolingual cusp and
distolingual cusp
- Supplementary grooves present
Upper molars, in general
- Thickness (Buccolingual) > Width (Mesiodistal)
- Two buccal roots and one palatal (longest root)
upper first molar
- Tubercle of carabelli present
- Occlusal surface is rhomboid with 4 cusps
- Mesiolingual is the largest cusp with tubercle of carabelli present
- Oblique ridge connects between ML (mesiolingual) and DB (distobuccal)
cusps - Roots are long and widely placed
upper second molar
- Occlusal surface is rhomboid (4 cusps) or heart-shaped (4 or 3 cusps)
- No tubercle of carabelli
- Roots are shorter and less widely placed
upper third molar
- Occlusal surface is rhomboid or heart-shaped
- No tubercle of carabelli
- Multiple supplementary grooves
- Root is short and fused
- No distal contact area
Lower molars, in general
- Width (Mesiodistal) > Thickness (Buccolingual)
- Two roots – mesial and distal
