• It is the 5th tooth of the maxillary arch in
• It can not be seen in primary dentition.
• It supports the first pre-molar in function.
• It resembles closely to the first pre-molar.
• Its less angular than first pre-molar.
• It gives rounded effect to the crown from all
• Single rooted.
• Crown of 2nd pre-molar is smaller cervico occlusally and mesio-distally.
• Root is longer than 1st pre-molar.
• Both the teeth are about same length but the
2nd pre-molar is greater in length.
• According to the universal tooth numbering
system its number is:
• Maxillary right is tooth # 4.
• Maxillary left is tooth # 13.
• Mandibular left is tooth # 20
• Mandibular right is tooth # 29.
• According to FDI system the tooth numbers
• Maxillary right is tooth # 15.
• Maxillary left is tooth # 25.
• Mandibular right is tooth 45 #.
• Mandibular left is tooth 35#.
First evidence of calcification = 2 – 2.5 yr
Enamel completed = 6 – 7 yr
Eruption 10 – 12 yr
Root completed 12 – 14 yr
• Buccal cusp is not long as of first pre-molar.
• Buccal cusp is less pointed.
• Mesial slope of buccal cusp ridge is shorter
than distal slope.
• The crown and root from this aspect are
thicker at their cervical portions
• Buccal ridge may not be prominent as that of
• Lingual aspect shows
• Lingual cusp is more
or less the same size
as buccal cusp.
• The root from this
side is tilted mesially.
• Maxillary 2nd pre-molar has 1 root, which is
usually as long or a millimeter longer than the
root of 1st pre-molar.