Maxillary first molars

• The maxillary first molars have 3 roots, which can all be seen from the buccal side
• The palatal root is the strongest and largest root
• The mesiobuccal cusp is broader, shorter, and less sharp than the distobuccal cusp
• The root trunk is about 4mm in length
• The axis of the roots are inclined more distally and there is a deep developmental groove that extends into the root trunk
• The mesiolingual cusp is the most prominent (largest and longest)
• The cusp of Carabelli is located on the mesiolingual cusp and forms 60% of the cusp surface
• There is a lingual developmental groove
• Mesially, the crown has a trapezoid outline, with the palatal side being more convex than the buccal
• The occlusal outline is rhomboidal
• The largest cusp is the mesiolingual, followed by the rounded mesiobuccal, the sharp distobuccal, the distolingual, and the cusp of Carabelli
• There is an oblique ridge running from the distobuccal cusp to the mesiolingual cusp (unique feature of the maxillary molars)