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Oral ulceration with bone sequestration: Retrospective study of eight cases and literature review.

OBJECTIVE
Oral ulceration with bone sequestration (OUBS) describes a site-specific intraoral ulcer that covers exposed, non-vital bone in patients lacking any etiological factor known to induce osteonecrosis. We aimed to conduct a retrospective study of eight new cases of OUBS and review the literature.


SUBJECTS AND METHODS
This is a retrospective study of OUBS cases, diagnosed and managed during 2007-2017. Inclusion criteria were the presence of oral ulcer with exposed non-vital bone at sites of bone prominence and the absence of any factor known to cause osteonecrosis. The English literature was reviewed on original OUBS cases.


RESULTS
Eight patients (5 males and 3 females, aged 27-75 years) were diagnosed with OUBS during years 2007-2017. Four cases involved the mandibular mylohyoid ridge, one a mandibular anterior exostosis and three the maxillary buccal/palatal exostoses. Exposed bone was removed under local anesthesia, resulting in complete healing in all cases. The literature review yielded 32 OUBS cases in the mandible.


CONCLUSION
Oral ulceration with bone sequestration is a distinct, probably under-reported rather than rare clinical entity that should be regarded the provisional diagnosis in case of an oral ulcer covering exposed, non-vital bone at sites of bone prominence in patients lacking any etiological factor known to induce osteonecrosis.