4- pulpal/periapical pathology + lesions

most common disease process that dentist encounters

inflammation

2 types of periapical inflammatory disease

1. rarefying osteitis

2. sclerosing osteitis

periapical inflammatory disease is a result of what 

caries/trauma → necrotic pulp → periapical inflammatory disease 

what happens once the disease spreads beyond the root apex

pericapical inflammatory disease → osteomyelitis

term for inflammation that is restricted to PDL

apical periodontitis

2 radiographic signs of apical periodontitis

1. widened PDL space

2. loss/thickening of lamina dura (radiopaque line that’s normally around the roots)

definition of rarefaction

loss of bone material 

definition of osteitis

inflammation of bone

what’s rarefying osteitis

chronic inflammation associated w/ non-vital tooth 

rarefying osteitis always involves 1 of which 3 things

1. abscess

2. granuloma

3. radicular cyst

what’s sclerosing osteitis

• sclerosis: hardening of bone

• increased radiopacity of bone w/ widened PDL

differentiate the pathology for #30 + #31

• #30: apical rarefying osteitis

• #31: developing tooth w/ open root apex

what’s the pathology of #7

apical rarefying osteitis

what’s the pathology of #30

apical sclerosing osteitis

describe the pathology 

apical sclerosing osteitis + radiolucency around PDL space 

T/F: trabeculae can become thicker + increase in number in periapical inflammatory disease

true 

what’s the arrow pointing to

periosteal new bone formation

what are the arrows pointing to

“Halo sign”: elevation/displacement of max sinus floor 

what’s the arrow pointing to

periosteal bone formation aka periostitis aka “onion skin” + mucosal thickening aka mucositis  

T/F: you can have rarefying + sclerosing osteitis at the same time

true

differentiate the pathology of the 2 images

• left: loss of apical lamina dura + periapical radiolucency

• right: normal lamina dura + radiolucency due to submandibular fossa

differentiate the pathology of the 2 images

• left: widened PDL + periapical radiopaque area + non-vital tooth → sclerosing osteitis

• right: normal PDL + periapical radiopaque area due to dense bone island + vital tooth → normal

what’s the pathology 

floor of max sinus elevated/displaced → rarefying osteitis 

what’s the pathology 

pneumatization of max sinus 

what’s the pathology 

mucus retention psuedocyst 

5 potential pathologies as a result of periapical inflammation 

1. parulis: “gum boil” 

2. periapical granuloma

3. periapical cyst

4. periapical abscess

5. condensing osteitis

3 clinical signs of parulis

1. dome-shaped yellow-pink papule

2. may/may not exhibit active suppuration (pus formation)

parulis is usually located where

on gingiva facial to non-vital tooth

2 histopath features of periapical granulomas

1. granulation tissue surrounded by fibrous connective tissue

2. lymphocytic infiltrate may be intermixed with neutrophils, plasma cells, histiocytes, and occasionally mast cells or eosinophils

describe the 3 structural components of a cyst

outer → inner

1. fibrous CT + granulation tissue

2. epithelium

3. lumen

T/F: periapical cysts are the most common odontogenic cyst

true

how does the epithelium form the lining of a periapical cyst

usually derived from rests of Malassez or from lateral aspect of root at orifice of accessory canal

2 histopath features of periapical cysts

1. lining of cyst composed of stratified squamous epithelium

2. wall of cyst consists of dense fibrous tissue w/ inflammatory infiltrate

periapical abscesses are a result of

accumulation of acute inflammatory cells @ apex of a non-vital tooth

3 clinical features of periapical abscesses

1. headache, fever, malaise, chills

2. tenderness of affected tooth

3. possibility to spread through bone (osteomyelitis) or perforate cortex + spread through soft tissue (cellulitis)

what’s a Phoenix abscess 

type of periapical abscess, acute exacerbation of chronic periapical inflammatory lesion

2 histopath features of periapical abscesses 

1. acute inflammatory cells, cellular debris, necrotic material, and bacterial colonies

2. Phoenix abscesses may include soft tissue component

3 tx options for periapical abscesses

1. Drainage

2. Elimination of infection

3. Antibiotics for medically compromised patients

2 tx options for condensing osteitis

1. endo therapy

2. ext

T/F: 85% of condensing osteitis cases will resolve or regress

true

2 tx options for non-vital teeth

1. RCT + biopsy of tissue

2. non-restorable → EXT + curettage of apical tissue

what happens if cortical plates have been lost after a non-vital tooth is treated

periapical fibrous scar formation

T/F: untreated cysts can turn into squamous cell carcinoma 

true, but it’s rare

what is this

chronic hyperplastic pulpitis: hyperplastic granulation tissue extrudes from pulp chamber

chronic hyperplastic pulpitis usually happens in which age

children + young adults w/ large pulp exposures

2 tx options for chronic hyperplastic pulpitis

1. endo

2. ext 

definition of osteomyelitis

inflammation that has extended from periapical region → marrow space, cortex, cancellous portion of bone + periosteum

6 types of osteomyelitis

1. acute osteomyelitis

2. chronic osteomyelitis

3. acute suppurative osteomyelitis

4. acute pyogenic osteomyelitis

5. proliferative periostitis

6. periostitis ossificans

acute osteomyelitis usually affects which 2 areas

1. mandible

2. premolar-molar area

6 clinical features of acute osteomyelitis

1. pain

2. swelling

3. redness

4. fever

5. purulent discharge

6. mobility in involved teeth

what happens if acute osteomyelitis is not treated 

chronic osteomyelitis, but can also occur de novo

T/F: acute osteomyelitis does not radiographically manifest in the early stages

true

once past the early stages, the periphery of acute osteomyelitis presents w/ what 3 radiographic features

1. poorly defined

2. non-corticated

3. gradual transition to normal trabeculae

once past the early stages, the internal structure of acute osteomyelitis presents w/ what 3 radiographic features

1. decreased bone density

2. loss of trabeculae sharpness

3. mixed radiolucent- radiopaque areas: “moth-eaten” appearance w/ irregular outline

4. sequestrum: islands of necrotic bone

what is the black arrow pointing to 

large sequestra caused by acute osteomyelitis 

4 radiographically visible effects on surrounding structures due to acute osteomyelitis

1. bone formation aka periosteal stimulation aka “onion skin” pattern

2. bone resorption

3. fistula

4. pathologic fracture 

what are the arrows pointing to

fistula due to acute osteomyelitis

what is the white arrow pointing to

periosteal reaction due to acute osteomyelitis

what are the arrows pointing to 

pathologic fracture of the L mandible due to acute osteomyelitis 

chronic osteomyelitis is called diffuse sclerosing osteomyelitis when it has which 3 features

1. proliferation of bone

2. subperiosteal bone deposition on large segment of mandible

3. slight jaw enlargement

what’s the pathology of the L mandible

diffuse sclerosing osteomyelitis of L angle-ramus of mandible

what’s the pathology of the R mandible

osteoradionecrosis (ORN), radiographically similar to osteomyelitis

T/F: bisphosphonate related osteonecrosis of the jaws (BRONJ) is radiographically indistinguishable from osteoradionecrosis + osteomyelitis

true

differentiate between the 2 radiographs

• L: osteomyelitis w/ ill-defined, mixed lesion of L body + ramus of mandible, “moth eaten” appearance 

• R: well-defined radiopaque lesions in max + mand, not osteomyelitis 

3 types of soft tissue inflammation seen radiographically

1. pericoronitis

2. sinusitis + mucositis in max sinus

3. mucus retention “pseudocyst”

2 radiographic signs of pericoronitis

1. periosteal reaction

2. sclerotic bone reaction (radiopaque)

what are the white + black arrows

• white: periosteal rxn

• black: sclerotic bone rxn

of pericoronitis

sinusitis + mucositis in max sinus are shown radiographically via 

sclerotic changes in boney walls 

3 radiographic features of mucus retention “pseudocyst”

1. relative radiopacity on floor of sinus

2. well-defined, not corticated

3. dome-shaped