Maxillary 2nd and 3rd Molar Anatomy PDF

Lecture(12) Maxillary second molar Principal identifying features 1- Fifth cusp is less evident. 2- Roots are less divergent, and may be joined together. 3- Both distal cusps are less developed. 4- The crown is smaller in overall d...

Lecture(12) Maxillary second molar Principal identifying features 1- Fifth cusp is less evident. 2- Roots are less divergent, and may be joined together. 3- Both distal cusps are less developed. 4- The crown is smaller in overall dimensions than the 6. Buccal aspect 1- The crown is shorter and narrower Mesio-distally. 2- The disto-buccal cusp is smaller, so some part of the distal surface is seen. 3- The roots are closer together. Lingual aspect 1- The disto-lingual cusp is smaller. 2- Part of the disto-buccal cusp is seen distal to the disto-lingual cusp. 3- No evidence of presence of the fifth cusp. Mesial aspect 1- The divergence of the roots is less than that of the max. first molar. Distal aspect 1- Because the disto-buccal cusp is smaller than the Mesio- buccal cusp more of the Mesio-buccal cusp is seen. Occlusal aspect 1- Rhomboidal shape of occlusal aspect is more visible (acute angles are less and obtuse angles are more). 2- Bucco-lingual diameter is the same as first molar, but Mesio- distal diameter is 1mm less. 3- The distal cusps are smaller and less developed. 4- No fifth cusp. Maxillary third molar:- Principal identifying features 1- Triangular occlusal outline. Disto-lingual cusp is often absent. 2- Roots are shorter, convergent, often fused, and usually are 3 in numbers. 3- smallest maxillary molar. 4- The Mesio lingual cusp is the largest. 5- It may have many variations occlusally: a)Heart shape type with three cusps. b) Rhomboidal shape type with four cusps. c) One cusp type (peg shaped). d) Congenitally missing.