Management of Osteomyelitis Flashcards
is it more common for odontogenic infections to spread to soft tissue/fascial spaces or osseous structures
soft tissue/fascial spaces
what is osteomyelitis
inflammation and infection of the bone marrow with a tendency to progression
where does osteomyelitis start
in the medullary bone and then continues to involve adjacent cortical plates and often periosteum - more frequently seen in the mandible
what happens if osteomyelitis is untreated
it progresses from inflammatory destruction of bone, to necrosis (sequestra)
in the oral region, osteomyelitis is usually a result of:
bacterial infection secondary to odontogenic infections and trauma
which jaw is osteomyelitis incidence higher in and why
mandible due to dense, poorly vascularized cortical plates
maxillary bone is:
much less dense with excellent blood supply
describe the mandible
-predominantly supplied by inferior alveolar neurovascular bundle
- overlying cortical plate is thick
describe the maxilla
- much more vascular than mandible as it receives blood supply from several arteries
- less dense than mandible
describe the course of osteomyelitis
indolent, yet progressive and persistent course
what are the immuno compromised status factors that can predispose to osteomyelitis
- DM
- malignancy
- AIDS
- patients taking chronic steroids, and chemotherapeutic agents
- patients on immunosuppressants
- tuberculosis
what are the conditions that affect the jaw vascularity
- H/O irradiation treatment
- advanced osteoporosis
- osteopetrosis
- late stage cemento osseous dysplasia
- osteitis deformans (paget disease)
osteomyelitis is primarily the result of:
odontogenic infections or trauma which cause inoculation of bacteria into the jaws
- results in an inflammatory cascade that is usually self limiting in the healthy patient
- with progression the condition is considered pathologic
what is the pathogenesis of osteomyelitis
- infection and associated inflammation (edema) spreads into marrow spaces and causes compression of blood vessels and therefore causes severe compromise of blood supply
- pus travels through haversian and volkaman’s canal and accumulation beneath the periosteum and elevating it from cortex and thereby reducing the blood supply
- ultimately cortical bone perforates, compromising periosteal blood supply as well
- reduced blood supply causes necrosis of the bone
- small section of necrotic bone may get completely lysed while large get localized and get separated from the shell of new bone by bed of granulation tissue
- the dead bone is surrounded by the new viable bone this is called involucrum
- then pus penetrate the periosteum and mucosal and cutaneous fistulate develop and thereby discharging the purulent pus
- intraoral or extraoral fistulas develop
what happens after an extraoral fistula
bacteria then proliferates as normal blood borne defenses do not reach the tissue and the osteomyelitis process spreads until it is stopped by surgery and medical treatment
what is the microbiology of osteomyelitis
- usually a mixed infection when involving the jaws
- alpha hemolytic streptococci and anaerobic bacteria (peptostreptococcus, fusobacterium, prevotella) recognized as prime pathologic species for osteomyelitis of the jaws
- osteomyelitis of the long bones usually caused by staphylococcus aureus
what are the classifications of acute osteomyelitis
- contiguous focus
- progressive
- hematogenous
- suppurative vs non suppurative
what is contiguous focus
the result of the spread of infection from an adjacent soft tissue focus such as wound, laceration, abscess, post operative infection