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Deciduous maxillary & mandibular 2 nd molar

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Jubin Babu
Jubin Babu

This document describes the anatomy of the deciduous maxillary and mandibular second molars. It details their features compared to the permanent first molars, including having smaller crowns but longer, more slender roots. The maxillary second molar has two prominent buccal cusps and three lingual cusps, while the mandibular second molar has two equal lingual cusps and three similar buccal cusps. Both teeth have pulp cavities with horns corresponding to the cusps and three root canals.

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DECIDUOUS MAXILLARY 2ND MOLAR Made by: Jubin Babu, 3rd year BDS
Chronology chart
BUCCAL ASPECT  The characteristics resembles those of the permanent maxillary 1st molar, but it is smaller  The buccal view of this tooth shows two well-defined buccal cusps with a buccal developmental groove between them.  The crown is narrow at the cervix in comparison with its M-D measurement at the contact areas.  The crown is much larger than that of the first primary molar.
Buccal aspect contd..  The root are slender, are much longer and heavier than those of maxillary first molar.  The point of bifurcation between the buccal roots is close to the cervical lone of the crown.  The two buccal cusp are more nearly equal in size and development than those of permanent maxillary 1st molar.
LINGUAL ASPECT Lingually , the crown shows the following three cusps; 1. The mesiolingual cusp, which is large and well developed 2. The distolingual cusp, which is well developed (more than primary 1st molar) and 3. A third supplemental cusp, which is apical to the mesiolingual cusp sometimes called the tubercle of carabelli , or the fifth cusp
Lingual aspect contd..  A well-defined developmental groove separates the mesiolingual cusp from the distolingual cusp and connects with the developmental groove, which outlines the fifth cusp.  All three roots are visible from this aspect.  Lingual root is large and thick in comparison with other two roots.
MESIAL ASPECT  The crown has typical molar outline that resembles that of the permanent molars very much.  The crown appears short because of its width buccolingually in comparison with its length.  The mesiolingual cusp of the crown with its supplementary fifth cusp appears large in comparison with the mesiobuccal cusp.
Mesial aspect contd.  Mesiobucaal root from this aspect is broad and flat.  The lingual root has somewhat same curvature as of 1st molar.  The mesiobuccal root extends lingually far out beyond the crown outline.  The point of bifurcation between the mesiobuccal root and the lingual root is 2 or 3 mm apical to the cervical line of the crown
DISTAL ASPECT  From both the distal and the mesial aspect the outline of the crown lingually creates a smooth, rounded line, whereas a line describing the buccal surface is almost straight from the crest of curvature to the tip of the buccal cusp.  The distobuccal cusp and the distolingual cusp are about the same in length. The cervical line is approximately straight , as was found mesially.
Distal aspect contd..  All three roots are seen from this aspect, although only apart of the outline of mesiobuccal root may be seen, since the distobuccal root is superimposed over it.  The distobuccal root is shorter and narrower than the other roots.  The point of bifurcation between the distobuccal root and the lingual root is more apical in location than any of the other point of bifurcation.
OCCLUSAL ASPECT  From the occlusal aspect, the tooth resemble the permanent first molar.  It is somewhat rhomboidal and has four well developed cusp: mesiobuccal, distobuccal, mesiolingual, distolingual and fifth supplemental cusp  The buccal surface is rather flat with the developmental groove between the cusp less marked than that found on the first permanent molar.
PULP CAVITY  The pulp cavity consist of a pulp chamber and 3 pulp canals corresponding to three roots.  These canals leave floor of the chamber at the mesiobuccal and distobuccal corners and from lingual area.  Pulp chamber has 4 pulpal horns, a fifth horn projecting from lingual aspect of mesiolingual horn may be present.  Mesiobuccal pulp horn is largest, pointed and extends occlusally.
 Mesiolingual pulp horn is second in size, when combined with fifth horn it presents a bulky appearance.  Distobuccal pulp horn is third in size, joining mesiolingual pulp horn as slight elevation.  Distolingual pulp horn is shortest and extends only slightly above occlusal level.
DECIDUOUS MANDIBULAR 2ND MOLAR It has characteristics that resemble those of the permanent mandibular first molar, although its dimensions differ.
BUCCAL ASPECT  How it differs from first molars?  It has a narrow M-D calibration at the cervical portion of the crown than at contact level.  The mandibular first permanent molar, accordingly, is wider at the cervical portion.  The roots are slender and long.  They have a characteristic flare mesiodistally at middle and apical thirds.  The point of bifurcation of the roots starts immediately below the CEJ.
LINGUAL ASPECT  Two cusps of almost equal dimensions seen, a short, lingual groove is between them.  The cervical line is relatively straight.  The mesial portion of the crown seems to be a little higher than the distal portion, thus appears tipped distally.
MESIAL ASPECT  Outline of the crown resembles permanent mandibular first molar.  The crest of contour buccally is more prominent  Marginal ridge is high  the lingual cusp is longer, or higher, than the buccal cusp.  The cervical line is regular  The mesial root is unusually broad and flat with a blunt & apex sometimes serrated
DISTAL ASPECT  The crown is not as wide distally as it is mesially; therefore, the mesiobuccal and distobuccal cusp from the distal aspect.  The distolingual cusp appears well developed, and the triangular ridge is seen over the distal marginal ridge.  The distal marginal ridge dips down more sharply and is shorter buccolingually than the mesial marginal ridge.  This cervical line of the crown is regular
Deciduous maxillary & mandibular 2 nd molar
Distal aspect contd..  The distal root is almost as broad as the mesial root is flattened on the distal surface.  The distal root tapers more at the apical end than does the mesial root
OCCLUSAL ASPECT  The occlusal outline is somewhat rectangular  The three buccal cusps are similar is size.  The two lingual cusps are also equally matched.  Well-defined triangular ridges seen  The distal triangular fossa is not as well defined as the mesial triangular fossa.  The mesial marginal ridge is better developed and more pronounced than the distal marginal ridge
PULP CAVITY  Pulp cavity is made up of a chamber & usually 3 pulp canals.  The two mesial pulp canals are confluent as they leave floor of pulp chamber through a common orifice.  Distal canal is constricted in the centre.
 Pulp chamber has 5 pulpal horns corresponding to 5 cusps.  Mesiobuccal and mesiolingual pulp horns are largest.  Distobuccal horn is smaller than mesial horns.  The distal horn is shortest and smallest occupying a position distal to distobuccal horn.
How its different from permanent ?  In the deciduous molar the mesiobuccal, distobuccal and distal cusp are almost equal in size and development.  The distal cusp of the permanent molar is smaller than the other two.  Because of the small buccal cusps, the deciduous tooth crown is narrower buccolingually, in comparison with its mesiodistal measurement , than is the permanent tooth.

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Deciduous maxillary & mandibular 2 nd molar

  • 1. DECIDUOUS MAXILLARY 2ND MOLAR Made by: Jubin Babu, 3rd year BDS
  • 3. BUCCAL ASPECT  The characteristics resembles those of the permanent maxillary 1st molar, but it is smaller  The buccal view of this tooth shows two well-defined buccal cusps with a buccal developmental groove between them.  The crown is narrow at the cervix in comparison with its M-D measurement at the contact areas.  The crown is much larger than that of the first primary molar.
  • 4. Buccal aspect contd..  The root are slender, are much longer and heavier than those of maxillary first molar.  The point of bifurcation between the buccal roots is close to the cervical lone of the crown.  The two buccal cusp are more nearly equal in size and development than those of permanent maxillary 1st molar.
  • 5. LINGUAL ASPECT Lingually , the crown shows the following three cusps; 1. The mesiolingual cusp, which is large and well developed 2. The distolingual cusp, which is well developed (more than primary 1st molar) and 3. A third supplemental cusp, which is apical to the mesiolingual cusp sometimes called the tubercle of carabelli , or the fifth cusp
  • 6. Lingual aspect contd..  A well-defined developmental groove separates the mesiolingual cusp from the distolingual cusp and connects with the developmental groove, which outlines the fifth cusp.  All three roots are visible from this aspect.  Lingual root is large and thick in comparison with other two roots.
  • 7. MESIAL ASPECT  The crown has typical molar outline that resembles that of the permanent molars very much.  The crown appears short because of its width buccolingually in comparison with its length.  The mesiolingual cusp of the crown with its supplementary fifth cusp appears large in comparison with the mesiobuccal cusp.
  • 8. Mesial aspect contd.  Mesiobucaal root from this aspect is broad and flat.  The lingual root has somewhat same curvature as of 1st molar.  The mesiobuccal root extends lingually far out beyond the crown outline.  The point of bifurcation between the mesiobuccal root and the lingual root is 2 or 3 mm apical to the cervical line of the crown
  • 9. DISTAL ASPECT  From both the distal and the mesial aspect the outline of the crown lingually creates a smooth, rounded line, whereas a line describing the buccal surface is almost straight from the crest of curvature to the tip of the buccal cusp.  The distobuccal cusp and the distolingual cusp are about the same in length. The cervical line is approximately straight , as was found mesially.
  • 10. Distal aspect contd..  All three roots are seen from this aspect, although only apart of the outline of mesiobuccal root may be seen, since the distobuccal root is superimposed over it.  The distobuccal root is shorter and narrower than the other roots.  The point of bifurcation between the distobuccal root and the lingual root is more apical in location than any of the other point of bifurcation.
  • 11. OCCLUSAL ASPECT  From the occlusal aspect, the tooth resemble the permanent first molar.  It is somewhat rhomboidal and has four well developed cusp: mesiobuccal, distobuccal, mesiolingual, distolingual and fifth supplemental cusp  The buccal surface is rather flat with the developmental groove between the cusp less marked than that found on the first permanent molar.
  • 12. PULP CAVITY  The pulp cavity consist of a pulp chamber and 3 pulp canals corresponding to three roots.  These canals leave floor of the chamber at the mesiobuccal and distobuccal corners and from lingual area.  Pulp chamber has 4 pulpal horns, a fifth horn projecting from lingual aspect of mesiolingual horn may be present.  Mesiobuccal pulp horn is largest, pointed and extends occlusally.
  • 13.  Mesiolingual pulp horn is second in size, when combined with fifth horn it presents a bulky appearance.  Distobuccal pulp horn is third in size, joining mesiolingual pulp horn as slight elevation.  Distolingual pulp horn is shortest and extends only slightly above occlusal level.
  • 14. DECIDUOUS MANDIBULAR 2ND MOLAR It has characteristics that resemble those of the permanent mandibular first molar, although its dimensions differ.
  • 15. BUCCAL ASPECT  How it differs from first molars?  It has a narrow M-D calibration at the cervical portion of the crown than at contact level.  The mandibular first permanent molar, accordingly, is wider at the cervical portion.  The roots are slender and long.  They have a characteristic flare mesiodistally at middle and apical thirds.  The point of bifurcation of the roots starts immediately below the CEJ.
  • 16. LINGUAL ASPECT  Two cusps of almost equal dimensions seen, a short, lingual groove is between them.  The cervical line is relatively straight.  The mesial portion of the crown seems to be a little higher than the distal portion, thus appears tipped distally.
  • 17. MESIAL ASPECT  Outline of the crown resembles permanent mandibular first molar.  The crest of contour buccally is more prominent  Marginal ridge is high  the lingual cusp is longer, or higher, than the buccal cusp.  The cervical line is regular  The mesial root is unusually broad and flat with a blunt & apex sometimes serrated
  • 18. DISTAL ASPECT  The crown is not as wide distally as it is mesially; therefore, the mesiobuccal and distobuccal cusp from the distal aspect.  The distolingual cusp appears well developed, and the triangular ridge is seen over the distal marginal ridge.  The distal marginal ridge dips down more sharply and is shorter buccolingually than the mesial marginal ridge.  This cervical line of the crown is regular
  • 20. Distal aspect contd..  The distal root is almost as broad as the mesial root is flattened on the distal surface.  The distal root tapers more at the apical end than does the mesial root
  • 21. OCCLUSAL ASPECT  The occlusal outline is somewhat rectangular  The three buccal cusps are similar is size.  The two lingual cusps are also equally matched.  Well-defined triangular ridges seen  The distal triangular fossa is not as well defined as the mesial triangular fossa.  The mesial marginal ridge is better developed and more pronounced than the distal marginal ridge
  • 22. PULP CAVITY  Pulp cavity is made up of a chamber & usually 3 pulp canals.  The two mesial pulp canals are confluent as they leave floor of pulp chamber through a common orifice.  Distal canal is constricted in the centre.
  • 23.  Pulp chamber has 5 pulpal horns corresponding to 5 cusps.  Mesiobuccal and mesiolingual pulp horns are largest.  Distobuccal horn is smaller than mesial horns.  The distal horn is shortest and smallest occupying a position distal to distobuccal horn.
  • 24. How its different from permanent ?  In the deciduous molar the mesiobuccal, distobuccal and distal cusp are almost equal in size and development.  The distal cusp of the permanent molar is smaller than the other two.  Because of the small buccal cusps, the deciduous tooth crown is narrower buccolingually, in comparison with its mesiodistal measurement , than is the permanent tooth.