Primary chronic osteomyelitis (chronic diffuse sclerosing osteomyelitis) of the mandible is an uncommon condition, probably arising as a consequence of infection with bacteria of low virulence, in which bone deposition rather than bone resorption occurs. These bacteria are most likely derived from skin or oral mucosa gaining access to bone from the periodontium or through the circulation. Furthermore, delayed hypersensitivity and ischaemic changes within bone may contribute to the inflammatory response, which once initiated is very difficult to eradicate. When the likely aetiological factors are considered a logical approach to management includes the surgical removal of affected bone and the topical application of a broad spectrum antibiotic to the resultant surgical bed.