Bone infection and necrosis Flashcards
(39 cards)
What is likely the cause of a acute periapical abscess?
Non-vital tooth. Source of infection is usually obvious! Pulp death could also be due to trauma where the tooth has no cavity.
Give me the clinical features of a periapical abscess
- Symptomatic or asymptomatic
- Becomes symptomatic as purulent material accumulates in the alveolus! Then it is percussion and mastication sensitive, does not respond to pulp test and swelling of the tissues occur.
- progresses and spreads: either through medullary spaces (causes osteomyelitis) or perforates cortical bone which drains through intra oral sinus.
- When draining, asymptomatic, but when drainage blocks it becomes symptomatic due to the pressure built up
- GP can be used to determine origin of infection with radiograph.
Give the radiological features of a periapical abscess
- Widen PDL
- Ill defined radiolucency!
- Phoenix abscess: outline of original chronic lesion with associated ill-defined bone loss (rises from ashes)
How do we treat a periapical abscess?
- Drainage: -excision
- root canal treatment
- soft tissue drainage - Eliminate focus of infection
- Use NSAIDS
- pre-op
- immediate post op - Antibiotic cover:
- not really needed as long as well localised or easily drained
- Needed in immunocomp pts, if there is cellulitis, or dissemination. - After RCT/extract!
- sinus tract will resolve self and bone will take awhile to heal. - If sinus tract persists then:
- curettage tract
- surgical removal
Give the pathogenesis of a periapical granuloma
Mass of chronically or subacutely inflammed granulation tissue at apex of non-vital tooth.
Does not show true granulomatous inflammation!
Formation of apical inflammatory lesions represent a defensive reaction secondary to presence of microbial infection in root canal that spread to apical zone. NB CAN DEVELOP FROM PERAIPICAL ABSECESS OR AS INTIAL LESION AND CAN DEVELOP INTO A PERIAPICAL CYST!!!
Give the clinical features of a periapical granuloma
- acute lesions (acute apical periodontitis) are symptomatic, pain on biting with no obvious alterations
- chronic lesions (chronic apical periodontitis) are asymptomatic!
Give the radiographic features of a periapical granuloma
- Early stages of infection see no radiographic alterations
- loss of apical lamina dura
- later detectable apical radiolucency which is small and barely predictable, can get greater than 2cm. Well circumscribed or ill defined.
Give the treatment of a periapical granuloma
- endodontic treatment and then evauluate every 1,3, 6 months then 1 yr and 2yr
- extract badly damaged teeth.
- Use NSAIDS in symptomatic cases
- Periapical surgery for lesions larger than 2cm! will curettage all peri-radicular soft tissue, amputate apical portion of root (apicectomy), seal the canal foramen, all soft tissue removed submitted for histological exam.
What is a periapical fibrous scar?
- sometimes periapical defects dont heal with normal bone but filled with fibrous tissue.
- often occurs when both buccal and lingual cortical plates are lost
- Often in areas with intact ortical plates
Supply the pathogenesis of condensing osteitis
Lesion is focal, periapical, hyperplastic bone reaction that results from chronic low grade pulpitis.
Excessive bone deposition without resorption results in increased bone density in periapical area of any tooth affected with either a chronic carious lesion or more commonly a leaking restoration. Its a localised area of bone sclerosis.
Give the clinical features of condensing osteitis
- Children and young adults in area of lower premolars and molars seen with pulpitis and pulpal necrosis.
- Pain generally not a feature but mild sensitivity may be present
- Most cases associated with md premolar and molars!
- expansion of area should not be present clinically
Give the radiological features of condensing osteitis
- Well defined radiopaque lesion up to 2cm in diameter
- At apical area
- associated with root apex of carious or heavy restored teeth with pulpitis or non vital teeth
- Lamina dura is intact!
- Periodontal space may be widened!
- NO radiolucent border (seen in focal or periapical osseous dysplasia)!
Give a differential diagnosis for the radiographic findings of condensing osteitis
- Focal osseous dysplasia:
- radiopacity with radiolucent rim
- lower molars
- middle age african females - Idiopathic osteosclerosis:
- radiopacity is separated from tooth apex
- Teeth in area are sound
How do we come up with a diagnosis of condensing osteitis?
Clinico-radiological features only
Biopsy not included
Treatment of condensing osteitis?
Eliminate the odontogenic focus or source of infection. Extract or do root canal. 85% cases regress partially or totally. Lesions may also resolve with normalisation of PDL space.
If radiopacity persists and PDL space stays widen then re-evaluate endo treatment or is a bone scar.
Explain what osteomyelitis is
Acute or chronic inflammatory process in medullary spaces or cortical surfaces of bone that extends away from site of involvement.
Explain primary osteomyelitis
- Ill defined group of inflammatory bone disorders.
- Idiopathic
- No obvious association with bacterial infection. Does not respond to antibacterial medications.
- suppuration and sequestra formation absent
Explain secondary (suppurative) osteomyelitis
Expanding lytic destruction of bone with suppuration and sequestra formation. Uncommon in developed countires but usually due to jaw fractures and immunosupression. Strong male predominance! Involves mandible more. In mx in children that arises from NOMA or NUG. Md is poorly vascularised compare to mx
What is the aetiology of secondary osteomyelitis? Or what are the predisposing factors of secondary osteomyelitis?
- After odontogenic infection
- after jaw trauma fractures
- gunshot wounds
- spreads from periodonitis
- spread from NUG
- spread from NOMA
- Chronic systemic diseases
- immunosupression
- decreased vascularity of bone leads to necrosis and inflammation.
- radiation
- osteopetrosis
- pagets disease
- end stage cemento-oeeous dysplasia
How do we diagnose osteomyelitis?
- Clinical and radiological features
- Bone biopsy for histology
Give the pathogenesis of acute suppurative osteomyelitis
Acute inflammatory process
Spreads through the medullary spaces.
Mandible is less vascular than the maxilla, making it more prone to osteomyelitis.
The acute inflammatory process present in the medullary spaces leads to extravasation of fluids and proteins with resultant occlusion of the thin walled blood vessels. This leads to further bone necrosis!
Give the clinical features of acute suppurative osteomyelitis
- Signs and symptoms of acute inflammation as well as systemic signs of infection
- Local sign and sympt include swelling due to oedema, pain and redness or draining fistula.
- swelling fluctuant but reactive bone formation and fibrosis leads to a firm swelling!
- affected bone becomes necrotic and separated from surrounding vital areas and eventually exfoliate through the overlying mucosa into oral cavity NB1
- associated teeth may be tender and moobile
- Paraesthesia of lower lip associated with mandible cases
- sequestra exfoliation (gets pushed out through the oral mucosa)
- Sytemically: fever, malaise, lymphadenopathy, leucocytosis
Give the radiological features of acute suppurative osteomyelitis
- Early in process no changes visible
- patchy irregular radiolucencies visible with progression (moth eaten appearance)
- widen PDL space loss of lamina dura
- loss of circumscribed IAN canal or mental foramen.
- sometimes central radiopaque masses representing the necrotic bone (sequestra) may be seen
Give the treatment of acute supurrative osteomyelitis
- Antibiotics: penecillin with metronidazole (good bone penetration) or clindamycin (also good bone penetration)
- surgical intervention: resolve source of infection, Drainage, remove infected bone and get samples for culture and antibiotic sensitivity testing. Reconstruction of mandible. If untreated will lea to cellulitis and septicaemia!
