Definition: Loss of bone due to inflammation. This term includes an abscess, cyst and/or granuloma as these can not typically be differentiated on a radiograph and are identified histopathologically. This is associated with a non-vital tooth. It takes 8 – 14 days for bone loss to be visible on a 2-D radiograph (periapical or pantomograph). A tooth may be necrotic without visible bone loss on a radiograph. Sometimes referred to as apical rarefying osteitis or lateral rarefying osteitis based on location.
Location: Associated with a tooth, typically found at the apex. Can be found on the lateral aspect of a root when associated with a lateral canal.
Edge: Well-defined to Well-localized.
Shape: Round to ovoid, starts as a tear-drop shape at the apex with the lamina dura and periodontal ligament space pulling away from a tooth apex or source of inflammation.
Number: May be single or multiple.
(click image to enlarge)
(left – arrow pointing to area of inflammation apical to the maxillary lateral incisor) (right-without arrow)
apical to maxillary lateral incisor
apical to maxillary left central incisor
apical to maxillary right posterior teeth
apical to mandibular first premolar
example of lateral rarefying osteitis on maxillary canine