Advanced Review of Pathology

Goals

How to approach a pathologic findings

Benign vs Malignant

Radiographic patterns to know

Periapical abscess, granuloma, cyst 

inflammatory RL lesions 

all periapical RL linked with non vital teeth=necrosis

can’t definitively differentiate radiographically

radiographic tendencies (not diagnostic)

• abscess-PDL widening, diffuse borders

• granuloma-small, well defined RL 

• cyst-larger, may show corticated border

diagnosis requires clinical tests (vitality testing) and/or biopsy 

Dentigerous cyst 

Developmental/odontogenic RL lesions

RL attached at CEH of an unerupted tooth

well defined, often corticated

displaces teeth

most common with mandibular 3rds and maxillary canines

Lateral periodontal cyst

Developmental/odontogenic RL lesions

RL between roots of vital tooth 

well circumscribed 

Odontogenic keratocyst (OKC)

Developmental/odontogenic RL lesions

well defined RL

smooth borders, scalloping may occur between roots

can be uni or multiocular

strong preference for posterior mandible 

high recurrence rate 

Simple bone cyst (traumatic bone cyst)

Developmental/odontogenic RL lesions

scallops between roots

vital teeth

uniocular RL

rarely any resorption or displacement of adjacent teeth

unlike OKC, SBC is NOT corticated or expansile 

Ameloblastoma

neoplastic RL

multiocular “soap bubble” or “honeycomb”

• may look uni when small

cortical expansion + thinning

aggressive but benign 

Condensing osteitis

RO lesion

RO at apex

linked with non vital tooth

no RL halo 

Odontoma

RO

Compound

• tooth like structure; denticles

• anterior maxilla

Complex

• RO mass with no tooth structures

• posterior mandible

Cementoblastoma

RO mass fused to root

surrounded by RL halo

may cause expansion

may cause displacement, resorption can occur

tooth remains vital

pain may be present, but not always 

Periapical cemento-osseous dysplasia (PCOD)

Mixed lesions

occurs in vital teeth

anterior mandible common

3 stage progression

• RL

• Mixed

• RO with thin RL border

often bilateral and symmetrical 

Fibrous dysplasia)

Mixed

ground glass look

borders blend into surrounding bone

loss of lamina dura

often unilateral expansion 

Paget’s disease

Mixed

cotton wool pattern

patchy irregular RO regions

may cause increased alveolar ridge size

possible increased spacing between teeth

linked with this disease (late stage) 

Osteosarcoma

Mixed

sunburst RO

widening PDL space without trauma

irregular destructive bone changes

pain and swelling clinically

malignant 

Border characteristics

Location

Key takeaways

Osteomyelitis

malignancy

moth eaten destructive RL