Permanent Posterior Teeth

Question 1

Upper first Premolar

Answer 1

• Two cusps Present (Lingual Cusp is shorter than buccal cusp by 1mm)
• Mesial slope of the buccal cusp is slightly longer than distal slope
• Canine fossae present on mesial surface
• MMDG is present on the mesial surface
• Occlusal surface is hexagonal in shape
• Longer central developmental groove
• Usually two roots present

Question 2

Upper Second Premolar

Answer 2

• No canine fossae
• No MMDG
• Mesial slope of the buccal cusp is shorter than distal slope
• Occlusal surface is oval in shape
• Buccal and lingual cusps are similar length
• Short central developmental groove
• Presence of supplementary grooves
• Mostly Single Root

Question 3

Lower First Premolar

Answer 3

• Severe Lingual Inclination
• Servere Lingual Convergence
• Occlusal Outline is diamond shape
• Snake eyes appearance (occlusal surface - 2 cusps)
• MLDG (tear drop) is present

Question 4

Lower Second Premolar

Answer 4

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