Volume 2 - Issue 2 - IJMD

Case ReportFig 7. Photograph showing the biopsy specimenFig 8. Histological section of the lesion revealing trabeculaeof irregular woven bone, in a fibrous connective tissue.mandible. Expansile lesions were also seen in sphenoidalbone, right ethmoidal sinus, orbit, frontal sinus, hardpalate and the zygomatic process of left maxilla. Laboratoryinvestigations like the parathyroid hormone assayrevealed that the level was 58pg/ml (7-53pg/ml), alkalinephosphatase level was 300U/L at 37’c up to 306U/L at37’c, serum calcium level was 8.2mg/dl (8.1 to 10.4mg/dl)and Serum phosphorus level was 2.8mg/dl (2.5 to 4.8mg/dl. Biopsy was done under local anesthesia. Histologicalexamination revealed trabeculae of irregular woven bone,in a fibrous connective tissue. There was no osteoblasticrimming seen around the bony trabeculae.Based on this, the final diagnosis was made as a rarecase of craniofacial monostotic fibrous dysplasia withbilateral involvement. Due to wide variety of involvementof the craniofacial regions, the treatment of this case isa multidisciplinary approach and the case was eventuallyreferred to a higher centre and later the patient had lostfollow up.DiscussionReed’s definition states that fibrous dysplasia is an arrest ofbone maturation, woven bone with ossification resultingfrom metaplasia of a nonspecific fibro osseous type. 2 FD iscaused due to the activating mutations in the GNAS genewhich encodes for the alpha subunit of the signalling Gprotein, Gs alpha. 3 FD has four different disease patterns.They are monostotic, polyostotic, craniofacial form andcherubism. Polyostotic form is again sub - classified intoJaffe’s type and Albright’s syndrome. Both types consist ofvarious bony involvements with cafe-au-lait spots. Albrightsyndrome has additional feature of endocrine disturbancesof various type. Polyostotic fibrous dysplasia with softtissue myxomas is called Mazabraud syndrome. 4Approximately 70 – 80% of fibrous dysplasias aremonostotic. It most frequently occurs in the ribs (28%),femur (23%), tibia, craniofacial bones and humerus, indecreasing order of frequency. FD is usually distributedin the unilateral side, although few cases of bilateralinvolvement have been reported. Maxilla is more commonlyaffected than mandible. 4 It involves one or two contiguousbones. 5 In this case, bilateral craniofacial bones of varioustypes are affected.Initial manifestations of fibrous dysplasia are most commonlyfound in patients aged 3 – 15 years. In monostotic diseasepatient as old as 20 or 30 years are asymptomatic. 4 Theaverage age of patients with craniofacial fibrous dysplasiais 20 to 30 years. 6 The incidence is equal in males andfemale. 2 But in this case, age of the patient is 55 years.The patients with monostotic FD is often asymptomaticand discovered incidentally on the radiological imaging forother reasons. The main clinical symptoms are caused bythe expanding mass, which may result in bony deformity,and nasal or sinus obstruction. 5 Cystic degeneration mayoccur spontaneously in the FD lesions years after the initialdiagnosis. 7 All the features correlate with the present case,except for the cystic degeneration which was absent.Radiograph usually reveals a lytic, ground glass lesionconsistent with FD. 8 Evaluation with CT scanning isparticularly valuable for the diagnosis of FD because itprovides information about the characteristic and extent ofthe lesion. This entity may be classified into 3 types basedon its CT appearance as follows: pagetoid, sclerotic andcystic. Pagetoid describes a mixture of dense and radiolucentareas of fibrosis; sclerotic lesions are homogenously dense,462Indian Journal of Multidisciplinary Dentistry, Vol. 2, Issue 2, February-April 2012