CHRONOLOGY AND MORPHOLOGY OF DECIDUOUS MANDIBULAR POSTERIORS.pptx

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1. CHRONOLOGY AND MORPHOLOGY OF DECIDUOUS MANDIBULAR POSTERIORS AND COMPARISION WITH THEIR PERMANENT COUNTERPARTS PRIYANKA MDS-1 st YEAR PEDODONTICS ITS DENTAL COLLEGE GREATER NOIDA

2. CHRONOLOGY

3. MORPHOLOGY OF FIRST MANDIBULAR MOLAR

4. MEASUREMENTS DECIDUOUS PERMANENT 6mm 9.8mm 7.5mm 14mm

5. BUCCAL ASPECT

6. D M M > D CUSPS (MB,DB) NO DEVLOPMENTAL GROOVES 2 ROOTS LINE FROM BIFURCATION BUCCAL ASPECT DEVELOPMENTAL DEPRESSION (divides 2 cusps) MANDIBULAR DECIDUOUS 1 st MOLAR

7. TRAPEZOIDAL 5 CUSPS M D DEVELOPMENTAL GROOVES (MB < DB) CONCAVE 3 mm BIFURCATION CERVICAL LINE ROOTS (M,D) BUCCAL ASPECT D C MB DB ML DL MB - WIDEST MANDIBULAR PERMANENT 1 st MOLAR

8. CUSPS DEVELOPMENTAL GROOVES BIFURCATION ROOT TRUNK DECIDUOUS PERMANENT BUCCAL ASPECT

9. LINGUAL ASPECT

10. M D ROOTS ML CUSP (in line with mesial root,characterstic ) DL CUSP (rounded) CERVICAL LINE (straight) MESIAL MARGINAL RIDGE(well dev) LINGUAL ASPECT DEVELOPMENTAL GROOVE (between 2 cusps) DECIDUOUS 1 st MOLAR

11. CUSPS D M MLC DLC DC LDG 4mm ROOT TRUNK LINGUAL ASPECT CERVICAL LINE (IRREGULAR) HIGH CUSP RIDGES TO HIDE BUCCAL CUSPS, FORMS ANGLE 100 DEGREE ROOTS APPEAR 1mm LONGER THAN BUCCALLY PERMANENT 1 st MOLAR

12. CERVICAL LINE DEVELOPMENTAL GROOVES CERVICAL BULGE DECIDUOUS PERMANENT LINGUAL ASPECT

13. MESIAL ASPECT

14. MESIAL ASPECT B L CURVATURE BUCCALLY AT CERVICAL THIRD CUSPS ML MB MESIAL MARGINAL RIDGE MB > ML(crown length) CERVICAL LINE (SLANTS BUCCOLINGUALLY) ROOT END ( flat.square ) DEVELOPMENTAL DEPRESSION DECIDUOUS 1 st MOLAR

15. MESIAL ASPECT 2 CUSPS (LC>BC), OPP 2 nd PREMOLAR ROOT RHOMBOIDAL L B MMR MCA DD CL BL DIMENSION IS GREATER THAN DISTAL MB ML PERMANENT 1 st MOLAR

16. RHOMBOIDAL BUCCOLINGUAL DIMENSION CERVICAL LINE MESIAL MARGINAL RIDGE ROOT END DECIDUOUS PERMANENT MESIAL ASPECT

17. DISTAL ASPECT

18. DISTAL ASPECT B L DB,DL CUSPS ARE SEEN DB DL DMR DMR – NOT STRAIGHT AND WELL DEVELOPED MB,ML CUSPS DISTAL ROOT CL DECIDUOUS 1 st MOLAR

19. DISTAL ASPECT DISTAL ROOT MR DBC MBC DLC MLC B L MMR DBDG CL DCA CR DC BUCCAL IS MORE CONVERGENCE THAN LINGUAL DISTAL ROOT IS MORE NARROW THAN MESIAL DISTAL CONTACT AREA IS PLACED BELOW DISTAL CUSP RIDGE DISTAL MARGINAL RIDGE IS SHORT PERMANENT 1 st MOLAR

20. DEVELOPMENTAL GROOVES MARGINAL RIDGES - DISTAL DECIDUOUS PERMANENT DISTAL ASPECT

21. OCCLUSAL ASPECT

22. OCCLUSAL ASPECT RHOMBOIDAL ML - LARGEST CG ENDS IN MESIAL PIT,SEPERATES MB ,ML DECIDUOUS 1 st MOLAR

23. OCCLUSAL ASPECT HEXAGONAL MESIODISTAL > BUCCOLINGUAL MB CUSP - LARGEST D M 1 MAJOR FOSSA – CENTRAL 2 MINOR FOSSAE – MESIAL AND DISTAL TRIANGULAR FOSSAE MB ML DB DC DL DEVELOPMENTAL GROOVES – CENTRAL,MESIOBUCCAL,DISTOBUCCAL,LINGUAL ALL DEVELOPMENTAL GROOVES CONVERGE IN THE CENTRE PERMANENT 1 st MOLAR

24. DECIDUOUS OCCLUSAL ASPECT PERMANENT SHAPE LARGEST CUSP MINOR AND MAJOR FOSSAE

25. MORPHOLOGY OF MANDIBULAR SECOND MOLAR

26. MEASUREMENTS DECIDUOUS PERMANENT 5.5mm 11.3mm 7mm 13mm

27. BUCCAL ASPECT

28. BUCCAL ASPECT M D 5 CUSPS MB DB DC DEVELOPMENTAL GROOVES (DIVIDES CUSPS IN EQUAL) MBDG DBDG ROOTS (SLENDER) NARROW MESIODISTAL AT CERVIX THAN AT CONTACT LEVEL BIFURCATION (starts immediately after cervical Line) DECIDUOUS 2 nd MOLAR

29. BUCCAL ASPECT 4 CUSPS CROWN SHORTER CERVICO-OCCLUSALLY AND NARROW MD THAN 1 st BDG CL ROOTS- SHORT THAN 1 st M D MBC DBC MLC DLC DBC – SHORTER THAN 1st PERMANENT MANDIBULAR 2 nd MOLAR

30. CUSPS DEVELOPMENTAL GROOVES MESIODISTAL DIMENSION AT CERVIX BIFURCATION DECIDUOUS PERMANENT BUCCAL ASPECT

31. LINGUAL ASPECT

32. LINGUAL ASPECT LG M D DLC MLC MESIAL SIDE IS HIGHER THAN DISTAL LINGUAL GROOVE ROOTS DIVERGING CL PRIMARY 2 nd MOLAR

33. LINGUAL ASPECT M D NO LINGUAL GROOVE DLC MLC ROOTS CONVERGING CL PERMANENT 2 nd MOLAR

34. LINGUAL GROOVE CERVICAL MESIAL AND DISTAL CUSP LENGTH ROOTS DECIDUOUS PERMANENT LINGUAL ASPECT

35. MESIAL ASPECT

36. MESIAL ASPECT RESEMBLES PERMANENT TOOTH B L CREST OF CONTOUR MORE PROMINENT BUCCALLY MMR CL EXTENDS UP BUCCOLINGUALLY MESIAL ROOT FLATTENED APPEARANCE OCCLUSALLY DECIDUOUS 2 nd MOLAR

37. MESIAL ASPECT CL – LESS CURVATURE L B NO FLATTENED APPEARENCE MESIAL ROOT IS POINTED APICALLY DISTAL ROOT PERMANENT 2 nd MOLAR

38. MESIAL MARGINAL RIDGE MESIAL ROOT CERVICAL LINE MESIAL ASPECT DECIDUOUS PERMANENT

39. DISTAL ASPECT

40. DISTAL ASPECT B L DL DB DISTAL ROOT DMR,MMR ARE SEEN CROWN IS LESS WIDE THAN MESIALLY CL DECIDUOUS 2 nd MOLAR

41. DISTAL ASPECT SIMILAR TO 1 st MOLAR CONTACT AREA(equidistant from cervical line and Marginal ridge) NO DC AND DBG DISTAL ROOT PERMANENT 2 nd MOLAR

42. CONTACT AREA IN PERMANENT IS EQUIDISTANT DISTAL ASPECT DECIDUOUS PERMANENT

43. OCCLUSAL ASPECT

44. OCCLUSAL ASPECT RECTANGULAR LINGUAL CUSPS ARE SIMILAR TRIANGULAR RIDGES – WELL DEVELOPED END IN CDG TRIANGULAR FOSSAE – MESIAL,DISTAL MBC = DBC = DC NARROW MD THAN PERMANENT DECIDUOUS 2 nd MOLAR

45. OCCLUSAL ASPECT B L BDG LDG CDG BDG AND LDG MEET CDG AT RIGHT ANGLE AND DIVIDE TOOTH IN 4 EQUAL PARTS RECTANGULAR D M PROMINENCE CERVICALLY ON MBC MORE CURVATURE DISTALLY PERMANENT 2 nd MOLAR

46. CUSPS DEVELOPMENTAL GROOVES OCCLUSAL ASPECT

47. THANK YOU