Understanding Human Teeth: Types, Numbers & Anatomy

Adults have 32 permanent teeth (including wisdom teeth), arranged in two arches (maxillary/mandibular), each with left and right quadrants.

Tooth Types & Counts (Per Arch)

Tooth	Per Quadrant	Per Arch	Total	Function
Central Incisor	1	2	4	Cutting, aesthetics, speech
Lateral Incisor	1	2	4	Cutting, aesthetics
Canine (Cuspid)	1	2	4	Tearing, cornerstone of arch
First Premolar	1	2	4	Crushing, tearing
Second Premolar	1	2	4	Crushing, grinding
First Molar	1	2	4	Grinding (largest crown)
Second Molar	1	2	4	Grinding
Third Molar (Wisdom)	1	2	4	Often impacted/extracted

Key Anatomical Features

• Crown: Enamel (hardest body tissue) → dentin → pulp (neurovascular).
• Root: Cementum → periodontal ligament → alveolar bone.
• Numbering Systems: Universal (1–32), FDI (two-digit), Palmer (quadrant + symbol).

Primary (Deciduous) Dentition

20 teeth: 8 incisors, 4 canines, 8 molars (no premolars). Erupt 6–30 months; exfoliate 6–12 years.

Variations: Hypodontia (missing), hyperdontia (supernumerary), impaction, fusion, gemination.