Mandible & maxilla

Osteomyelitis and inflammatory conditions

Osteomyelitis overview

Last author update: 1 July 2014
Last staff update: 8 July 2020

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PubMed Search: Osteomyelitis [title] mandible maxilla

Annie S. Morrison, M.D.
Kelly Magliocca, D.D.S., M.P.H.
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Cite this page: Morrison A. Osteomyelitis overview. website. Accessed September 26th, 2023.
Definition / general
  • Originates from Greek words osteon (bone) and muelinos (marrow)
  • While the original derivation emphasizes involvement of marrow, common medical literature extends the definition to an inflammation process of the entire bone including cortex and periosteum, recognizing that the pathological process is rarely confined to the medullary portion
  • Osteomyelitis has been used to encompass a wide variety of pathoses / etiologies, such as traumatic injuries, radiation, and certain chemical substances, but the term is mostly often used to describe infection of the bone
    • Osteomyelitis of the jaws is predominantly a disease of the mandible, because the maxilla is vascular with thin cortical plates and less frequently involved
    • When infection becomes established, pus or edema in the medullary cavity and beneath the periosteum can compromise the local blood supply
      • Ischemia can lead infected bone to become necrotic and sequester which is considered a classical sign of osteomyelitis
    • Osteomyelitis of the jaws is still fairly common in maxillofacial clinics and offices despite the introduction of antibiotics and the improvement of dental and medical care
  • Infection of the jaws, due to its unique feature bearing teeth and connecting to the oral cavity / oral environment with the periodontal membrane, differs in several important aspects from osteomyelitis of long bones
    • The specific local immunological and microbiological aspects determine a major factor in the etiology and pathogenesis of this disease and hence also have a direct impact on its treatment; therefore, to extrapolate from long bone infections to disease of the jaws has limitations
    • This is reflected by the longstanding recognition of osteomyelitis of jawbones as a clinical entity which differs in many important aspects from that in long bones; hence, a wide variety of classifications, specifically for the jawbones, have been established
    • Classifications are based on different aspects such as clinical course, pathological–anatomical or radiological features, etiology and pathogenesis
    • A mixture of these classification systems is often used, leading to confusion, hindering comparative studies and obscuring classification criteria
  • The Zurich system of osteomyelitis is generally accepted as the most reliable classification for osteomyelitis
  • Classification is primarily based on clinical course and imaging
  • Cortical bone
    • Cortical bone, synonymous with compact bone, is one of the two types of osseous tissue that form bones
    • Forms the cortex, or outer shell, of most bones
    • Much denser than cancellous bone, the other type of osseous tissue; is also harder, stronger and stiffer than cancellous bone
  • Medullary bone / medullary cavity / marrow cavity
    • The medullary cavity (medulla, innermost part) of bone is the central cavity where red bone marrow or yellow bone marrow (adipose tissue) is stored; hence, the medullary cavity is also known as the marrow cavity
    • The medullary cavity has walls composed of spongy bone (cancellous bone) and is lined by endosteum which are osteoprogenitor cells
  • Periosteum
    • Connective tissue membrane lining the outer / external surface bones except at the joints of long bones
    • Is composed of an outer fibrous layer and an inner cambium / osteogenic layer
  • Periapical granuloma
    • Acute or chronic inflammation admixed with fibrous or granulation tissue locally at the apical or periapical region of a tooth
    • Is devoid of epithelium (i.e. no cyst lining) which distinguishes it from a periapical cyst
    • Periapical granuloma is located at the apex of a necrotic or partially necrotic tooth root
  • Biofilm
    • Collection of microorganisms often embedded in a self produced extracellular polymeric matrix which allows them to adhere to or coat the surface of a living or inanimate structure
  • Acute suppurative osteomyelitis
    • Early phase of osteomyelitis, usually suppurative (pus forming)
    • Exists when an acute inflammatory process moves away from the site of initial infection and spreads through the medullary space of the bone and, in most cases, insufficient time has passed for the body to react to the presence of the inflammatory infiltrate
    • Acute phase may lead to the chronic phase which has been arbitrarily defined as an osseous infection lasting at least 1 month
  • Chronic osteomyelitis
    • Classified as primary or secondary, suppurative or non-suppurative
      • Chronic suppurative (or non suppurative) osteomyelitis: generally regarded as a secondary osteomyelitis characterized by a defensive response that leads to production of granulation tissue which subsequently forms dense scar tissue in an attempt to wall off the infected area
        • The encircled dead space acts as a reservoir for bacteria and antibiotics have great difficulty reaching the site
        • Acute and secondary chronic osteomyelitis: basically the same disease separated by the arbitrary time limit of 1 month after disease onset
        • Suppuration, fistula formation and sequestration are characteristic features
        • Depending on the intensity of the infection and the host bone response, the clinical presentation and course may vary significantly
        • Acute and secondary chronic osteomyelitis of the jaws: caused mostly by a bacterial focus (e.g. odontogenic disease, pulpal and periodontal infection, extraction wounds, foreign bodies, infected fractures)
      • Primary chronic osteomyelitis (PCO): often confused with, but must be distinguished from, chronic suppurative osteomyelitis (secondary chronic osteomyelitis)
        • No obvious association with a bacterial infection
        • No suppuration or sequestration characteristically
        • May be due to altered immune response to an organism of low virulence but no single theory has received widespread acceptance
  • Chronic recurrent multifocal osteomyelitis (CRMO)
    • Characterized by an inflammatory process presenting with findings similar to infectious osteomyelitis but no infectious source is identifiable
    • Often affects preteen and teenage patients
    • Often polyostotic and may affect the mandible
    • May represent a widespread variant of primary chronic osteomyelitis
    • CRMO and SAPHO (synovitis, acne, pustulosis, hyperostosis, osteitis) are distinguished from other forms of osteitis / osteomyelitis as these two diseases may have extragnathic skeletal involvement
  • Chronic tendoperiostitis
    • Initially thought to be an obscure infectious process, the clinical presentation is similar to that of primary chronic osteomyelitis
    • May represent a reactive alteration of bone initiated and exacerbated by chronic overuse of the masticatory muscles, predominantly the masseter and digastric
  • Chronic sclerosing osteomyelitis / diffuse sclerosing osteomyelitis
    • Medullary osseous infection, probably bacterial, induces the complete sclerosis
    • More common in young women; painful; appears radiographically as medullary sclerosis
    • Therapy includes antibiotics, surgical debridement and hyperbaric oxygen therapy in refractory cases
  • SAPHO syndrome
    • Acronym for a complex clinical presentation that includes synovitis, acne, pustulosis, hyperostosis and osteitis
    • The osseous lesions mirror primary chronic osteomyelitis and CRMO
    • Unknown cause but thought to arise in genetically predisposed individuals who develop an autoimmune disturbance secondary to exposure to dermatologic bacteria
    • Increased prevalence of histocompatibility antigen 27 noted
    • SAPHO and CRMO distinguished from other forms of osteitis / osteomyelitis as these two diseases may have extragnathic skeletal involvement
  • Garrè's sclerosing osteomyelitis:
    • In 1893, Swiss physician Carl Garrè reported on patterns of acute osteomyelitis
    • Garrè did not have any pathologic specimens for microscopic examination nor radiographs to augment his descriptions
    • Nonetheless, his name is often associated with the condition in which periosteal duplication, or "onion-skinning" pattern of periostitis leads to enlargement of the jaw, usually mandible
      • Garrè's osteomyelitis and Garrè's sclerosing osteomyelitis are often used synonymously, and should be disassociated with this clinical presentation
      • Note that Garrè's name was and is often misspelled as Garré with an improper accent
    • Numerous synonyms for Garrè's sclerosing osteomyelitis have been used:
      • Chronic osteomyelitis with proliferative periostitis
      • Chronic sclerosing osteomyelitis of Garrè
      • Chronic non-suppurative osteomyelitis with proliferative periostitis
      • Garré's chronic sclerosing osteomyelitis
      • Garré's chronic nonsuppurative sclerosing osteitis
      • Garré's proliferative periostitis
      • Garré's sclerosing osteomyelitis
      • Ossifying periostitis
      • Osteomyelitis of Garré
      • Osteomyelitis sicca
      • Osteomyelitis with proliferative periostitis
      • Periostitis ossificans
      • Sclerosing osteomyelitis of Garré
      • Sclerosing osteomyelitis of Garrè
  • Proliferative periostitis
    • Periosteal reaction to inflammation
    • The affected periosteum forms several rows of reactive vital bone that parallel each other and expand the surface of the altered bone
  • Osteoradionecrosis (ORN)
    • Clinically, a chronic non-healing wound of the affected jaw (most commonly mandible), typically with exposure of bone, in a patient with a history of radiation therapy to the head and neck region
    • Radiation injury to jaw that leads to ORN results from chronic hypovascularity, hypocellularity of marrow space and ultimately hypoxemia
    • Is more similar to avascular necrosis of bone than primary infection of bone, although infection or bacterial colonization can occur
  • Osteochemonecrosis of the jaws
    • Synonyms: bisphosphonate related osteonecrosis of the jaws, bisphosphonate induced osteonecrosis of the jaw, osteonecrosis of jaw, bisphosphonate osteonecrosis, bis-phossy jaw
    • Necrosis of bone related to long term use of antiresorptive medications such as bisphosphonate medications and altered bone metabolism
    • Osteoclasts are thought to be qualitatively impaired, particularly with intravenous forms of bisphosphonate medication which leads to inadequate remodeling of bone and necrosis
  • Condensing osteitis
    • Localized areas of radiographic bone sclerosis associated with the apices of inflamed dead or dying teeth (pulpitis or pulpal necrosis)
    • The association with an area of inflammation, usually a neighboring tooth, is critical because these lesions can resemble other intrabony processes
    • Is not considered a true osteomyelitis
  • Alveolar osteitis / Fibrinolytic alveolitis
    • After extraction of a tooth, a blood clot is formed at the extraction site with eventual organization by granulation tissue and gradual replacement by bone
    • Destruction of the initial clot is thought to delay the above steps required for extraction site healing and leads to a clinical condition known as alveolar osteitis
    • Clot is lost secondary to transformation of plasminogen to plasmin with subsequent lysis of fibrin and formation of kinins, which are potent pain mediators
Spectrum of Classification Systems Related to Gnathic Osteomyelitis
  • Hjorting-Hansen E., Decortication in treatment of osteomyelitis of the mandible: Oral Surg Oral Med Oral Pathol 1970;29:641
    • Classification based on clinical picture and radiology
      1. Acute / subacute osteomyelitis
      2. Secondary chronic osteomyelitis
      3. Primary chronic osteomyelitis
  • Panders AK, Hadders HN. Chronic sclerosing inflammations of the jaw: Oral Surg Oral Med Oral Pathol 1970;30:396
    • Classification based on clinical picture
      1. Acute osteomyelitis
      2. Secondary chronic osteomyelitis
      3. Primary chronic osteomyelitis
      4. Special forms
  • Marx R. Chronic Osteomyelitis of the Jaws: Oral Maxillofac Clin North Am 1991;3:367
    • Classification based on clinical picture and radiology, etiology, pathophysiology
      1. Acute osteomyelitis
        1. Associated with hematogenous spread
        2. Associated with intrinsic bone pathology or peripheral vascular disease
        3. Associated with odontogenic and nonodontogenic local processes
      2. Chronic osteomyelitis
        1. Chronic recurrent multifocal osteomyelitis of children
        2. Garre's osteomyelitis
        3. Chronic suppurative osteomyelitis
          • Foreign body related
          • Systemic disease related
          • Related to persistent or resistant organisms
        4. True chronic diffuse sclerosing osteomyelitis
  • Hudson JW, Osteomyelitis of the jaws: a 50-year perspective: J Oral Maxillofac Surg 1993;51:1294
    • Classification based on clinical picture and radiology
      1. Acute forms of osteomyelitis (suppurative or nonsuppurative)
        • Contagious focus
          1. Trauma
          2. Surgery
          3. Odontogenic Infection
        • Progressive
          1. Burns
          2. Sinusitis
          3. Vascular insufficiency
        • Hematogenous(metastatic)
          1. Developing skeleton (children)
      2. Chronic forms of osteomyelitis
        • Recurrent multifocal
          1. Developing skeleton (children)
          2. Escalated osteogenic (activity < age 25 years)
        • Garre's
          1. Unique proliferative subperiosteal reaction
          2. Developing skeleton (children and young adults)
        • Suppurative or nonsuppurative
          1. Inadequately treated forms
          2. Systemically compromised forms
          3. Refractory forms (chronic recurrent multifocal osteomyelitis)
        • Diffuse sclerosing
          1. Fastidious microorganisms
          2. Compromised host / pathogen interface
  • Topazian RG. Osteomyelitis of the Jaws: Topazian: Oral and Maxillofacial Infections, 4th Edition, 2002 (pg. 251 - 88)
    • Classification based on clinical picture,radiology, etiology (specific forms such as syphilitic, tuberculous, brucellar, viral, chemical, Escherichia coli and Salmonella osteomyelitis are not integrated in classification)
      1. Suppurative osteomyelitis
        1. Acute suppurative osteomyelitis
        2. Chronic suppurative osteomyelitis
          • Primary chronic suppurative osteomyelitis
          • Secondary chronic suppurative osteomyelitis
        3. Infantile osteomyelitis
      2. Nonsuppurative osteomyelitis
        1. Chronic sclerosing osteomyelitis
          • Focal sclerosing osteomyelitis
          • Diffuse sclerosing osteomyelitis
        2. Garre's sclerosing osteomyelitis
        3. Actinomycotic osteomyelitis
        4. Radiation osteomyelitis and necrosis
  • Bernier S et al., Osteomyelitis of the jaws: J Can Dent Assoc 1995;61:441
    • Classification based on clinical picture and radiology
      1. Suppurative osteomyelitis
        1. Acute suppurative osteomyelitis
        2. Chronic suppurative osteomyelitis
      2. Nonsuppurative osteomyelitis
        1. Chronic focal sclerosing osteomyelitis
        2. Chronic diffuse sclerosing osteomyelitis
        3. Garre's chronic sclerosing osteomyelitis (proliferative osteomyelitis)
      3. Osteoradionecrosis
  • Zurich Classification: Baltensperger M, et. al.: J Craniomaxillofac Surg 2004;32:43
    • The Zurich classification system of osteomyelitis is primarily based on clinical course and imaging
    • Histopathology is considered a secondary classification criterion because findings are mostly unspecific and inconclusive when considered by themselves; however, tissue examinations of biopsies are irreplaceable to confirm the diagnosis in cases of unclear and atypical clinical and radiological appearance and to exclude possible differential diagnoses
    • The three major classifications are:
      1. Acute Osteomyelitis (AO)
      2. Secondary Chronic Osteomyelitis (SCO)
      3. Primary Chronic Osteomyelitis (PCO)
    • Further subclassification is based on the presumed etiology and pathogenesis of disease
    • These criteria are therefore considered tertiary classification criteria and are helpful in determining the necessary therapeutic strategies which may differ somewhat among the subgroups
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