MANDIBULAR 2ND MOLAR - looks different from other molars TYPE TRAITS OF MANDIBULAR 2ND MOLAR •
BUCCAL SURFACE 1. Smaller crown than 1st Molar but bigger than 3rd Molar 2. MBC & DBC separated by Bu groove 3. 1 Bu groove 4. Roots closer together and inclined distally; apical 3rd distally inclined 5. intermediate in (width) size
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LINGUAL SURFACE 1. Li cusp is higher & more conical than Bu cusp 2. Length: crown shorter occlusocervically than mand 1st Molar 3. Bu profile & proximal surface not visible 4. Crown not as narrow at cervix 5. roots have a more pronounced distal inclination 6. MD profiles not converged too much towards neck
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MESIAL SURFACE 1. resembles 1st Molar 2. MRoot not as broad with sharp apex 3. Crown is rhomboidal and Bu is inclined towards Li 4. MMR occlusally positioned
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DISTAL SURFACE 1. D cusp is missing 2. Less of the Bu surface is visible 3. D is as large as 1st Molar 4. DRoot is narrower Bu-Li and has pointed tip 5. DBC, DLC and apices of Mesial cusp are visible 6. Triangular Ridges are visible 7. MR wider than DR
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OCCLUSAL SURFACE 1. Rectangular outline 2. Bu profile = Li profile 3. M & D profiles similar in width 4. M & D profiles are curved, no Li convergence 5. Most prominent portion of the Bu profile is at the region of the MBC 6. Maximum Bu-Li diameter M to BG
7. 2 Mesial cusps: widest MD than 2 Distal cusps; longer Bu-Li than DC 8. Most prominent Bu-Li diameter M to BG 9. BG divides 2 Bu cusps 10. Occlusal Table Outline: rectangular 11. BC & LC form the long sides 12. MRoots form the short sides 13. Has MBC, DBC, MLC & DLC 14. 2 Mesial cusps wider MD than Distal cusps 15. Marginal ridges have slight Li convergence 16. MMR slightly wider BC 17. No marginal grooves crossing MMR & DMR 18. +4 groove pattern - Rosette Go 091108