In periodontal disease, not only does the bone that supports the teeth, known as alveolar bone, reduce in height in relation to the

teeth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tear ...

, but the

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

of the remaining alveolar bone is altered.Carranza, FA: Bone Loss and Patterns of Bone Destruction. In Newman, MG; Takei, HH; Carranza, FA; editors: ''Carranza’s Clinical Periodontology'', 9th Edition. Philadelphia: W.B. Saunders Company, 2002. page 363. The bone destruction patterns that occur as a result of periodontal disease generally take on characteristic forms. Mand Right Premolar PA

Types of destruction

There are four chief types of bone defects that present in the alveolar bone: # horizontal defects # vertical, or angular, defects # fenestrations # dehiscences

Horizontal defects

Generalized bone loss occurs most frequently as horizontal bone loss. Horizontal bone loss manifests as a somewhat even degree of bone resorption so that the height of the bone in relation to the teeth has been uniformly decreased, as indicated in the radiograph to the rig defects occur adjacent to a tooth and usually in the form of a triangular area of missing bone, known as ''triangulation''.

References

{{Periodontology Dentistry