28.1

Types of Bone

Cortical bone​

The cortical bone, also referred to as compact bone, is a dense outer layer of bone​ that appears radiopaque on a radiograph​. The inferior border radiopaque of the mandible is composed of cortical bone​.

Cancellous bone​

The cancellous bone is a soft, spongy bone located between two layers of dense cortical bone​. It appears primarily radiolucent​. Trabeculae (bony spicules) appear Trabeculae Radiopaque, while marrow spaces appear Bone marrow Radiolucent

Prominences of Bone

Prominences of bone appear radiopaque on dental images. There are five types of prominences: process, ridge, spine, tubercle, and tuberosity.

Types of prominences:​
Process: marked prominence or projection

Example: Coronoid process of the mandible

 Coronoid process (of mandible)
Ridge: linear prominence or projection

Example: Internal oblique ridge
Spine: sharp, thornlike projection

Example: Anterior nasal spine of the maxilla
Tubercle: small bump or nodule

Example: Genial tubercles of the mandible
Tuberosity: rounded prominence

Example: Maxillary tuberosity

Spaces and Depressions in Bone

Spaces and depressions in bone do not resist the passage of the x-ray beam and appear radiolucent on dental images. There are four spaces and depressions in bones: canal, foramen, fossa and sinus.

Spaces and Depressions in Bone
Canal: tubelike passageway through bone that contains nerves and blood vessels​

Example: Mandibular canal
Foramen: opening or hole that permits the passage of nerves and blood vessels​

Example: Mental foramen of the mandible
Fossa: broad, shallow, scooped-out, or depressed area​

Example: Submandibular fossa of the mandible​
Sinus: hollow space, cavity, or recess in bone​

Example: Maxillary sinus

Miscellaneous Terms

Septum

A bony wall or partition that divides two spaces or cavities​. A septum may be present within the space of a fossa or sinus​. Appears radiopaque on a radiograph.

  • Example: Nasal Septum

Suture

An immovable joint representing a line of union between adjoining bones of the skull​. This thin line appears radiolucent​.

  • Example: Median palatine suture of the maxilla

 

Practice Makes Perfect

License

Icon for the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License

DE 115: Dental Radiography Copyright © 2024 by verabodnarchuk; monicacoggin; alisonloach; and rbhatia2 is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, except where otherwise noted.

Share This Book