Internal Anatomy of Teeth Dr. Mohammad Hammad

Endodontics is a specialty of dentistry, that deals with the tooth pulp and tissues surrounding the root of a tooth.

Why do we need to perform root canal treatment? Irreversibly inflamed pulp (pulpitis). Pulp Necrosis.

What are the general steps of root canal treatment? Access cavity. Cleaning and shaping of the canals. Obturation (filling) of the canals.

Root canal system: chamber and canals. Root canals begins at the orifice and ends at the apical foramen. Most root canals are curved. Accessory canals: small canals extending from pulp to peridontium (horizontal, vertical, lateral or furcational).

Basic anatomy of a molar tooth

Vertucci’s canal configuration A root with a tapering canal and a single foramen is the exception rather than the rule. Type I: single canal extending from pulp chamber to the apex (1).

Type II: Two separate canals leaving the pulp chamber but join short from the apex (2-1).

Type III: one canal leaving the pulp chamber that divides into 2 canals then merges again to exit as one canal (1-2-1).

Type IV: two separate canals extending from pulp chamber to apex (2).

Type V: One canal leaving the pulp chamber and divides and exits the apex as two separate canals (1-2).

Type VI: two separate canals leaving the pulp chamber then unite to form one canal then divides and exit as two canals (2-1-2).

Type VII: One canal leaving the pulp chamber then divides into two canals then unite to form one canal then re-divides and exit as two canals (1-2-1-2).

Type VIII: three separate canals leaving the pulp chamber and exit the apex (3).

Wein’s four possible canal configurations

Apical root anatomy

Apical constriction=minor apical diameter: the narrowest part of the canal. Apical foramen= major apical diameter. Cementodentinal junction. AF not usually coincident with anatomical apex.

Apical constriction 1mm Apical foramen 2mm Anatomical apex