Dental Anatomy: Upper Incisors and Canine

Upper Central Incisor

• Average length is 22.5 mm (range: 21 – 25.6 mm).
• Predominantly has one canal (99.4%), with a 0.6% chance of a second canal and 24% lateral canals.
• Curvature details:
  • Straight: 75%
  • Distally curved: 8%
  • Mesially curved: 4%
  • Labial: 9%
  • Lingual: 4%
• Pulp chamber is centrally located with three pulp horns (mamelons), wider mesiodistally.
• Root canal has one main canal; 24% have lateral canals near the apical region, with various curvature types.

Upper Lateral Incisor

• Average length is 21 mm (range: 20.5 – 25.1 mm).
• One canal present in 93.4% of cases, with 6.6% having a second canal and 10% with lateral canals.
• Curvature details:
  • Straight: 30%
  • Distally curved: 53%
  • Mesially curved: 3%
  • Labial: 4%
  • Bayonet: 6%
• Pulp chamber located centrally with two pulp horns, larger than that of the lower central incisor.
• Root canal is finer than upper central incisor, wider labiolingually.

Upper Canine

• Largest in the upper arch with an average length of 26.5 mm (range: 23.1 – 28.9 mm).
• Predominantly has one canal (96.5%), with a 3.5% chance of a second canal (buccal-lingual) and 24% lateral canals.
• Curvature details:
  • Straight: 39%
  • Distally curved: 32%
  • Labial: 13%
  • Lingual: 7%
  • Bayonet: 7%
• Triangular pulp chamber, centrally located with one pulp horn, wider labiolingually.

Lower Central Incisor

• Smallest tooth with an average length of 21.5 mm (range: 19.6 – 23.4 mm).
• One canal present in 73%, occasionally two canals are found (26% with one foramen, 6.5% with two foramina).
• Curvature details:
  • Straight labial canal: 60%
  • Distal curve: 23%
  • No mesial curves or lingual curves.
  • Labial curve: 13%
• Pulp chamber located centrally with three pulp horns.

Lower Lateral Incisor

• Average length is 22.4 mm (range: 20.2 – 24.6 mm).
• One canal present in 56.9% of cases, with variations including up to 29.4% with two canals.
• Curvature details:
  • Straight labial canal: 60%
  • Distal curve: 23%
  • Mesial curve: 0%
  • Labial curve: 13%
• Pulp chamber is similar to the lower central incisor but larger.

Lower Canine

• Average length is 25.2 mm (range: 22.9 – 27.5 mm), similar to the upper canine but smaller.
• Predominantly has one canal (94%), with a 6% chance of a second canal and 9.5% lateral canals.
• Curvature details:
  • Straight labial canal: 68%
  • Distal curve: 20%
  • Mesial curve: 1%
  • Lingual curve: 0%
  • Bayonet: 2%
• Pulp chamber is centrally located with one pulp horn.