Analyses of variable panoramic radiographic characteristics of maxillo-mandibular fibrous dysplasia in McCune-Albright syndrome.
OBJECTIVE
Fibrous dysplasia (FD) is a rare skeletal disease caused by activating GNAS1 gene mutations often found in association with the McCune-Albright syndrome (MAS). Multiple bones may be affected in FD, including maxilla and mandible. Patients with MAS have different endocrinopathies that can further influence bone metabolism. The purposes of this cross-sectional study are to characterize FD panoramic radiographic patterns, and to evaluate the effects of age, endocrinopathies and renal phosphate wasting on radiographic characteristics of maxillo-mandibular FD in MAS.


METHODS
Fifty-one consecutive MAS patients were screened and panoramic radiographs of 43 patients with craniofacial FD were evaluated and analyzed for FD involvement. Clinical chemistries were evaluated for associations between radiographic patterns and age, endocrinopathies or renal phosphate wasting using Fisher's Exact Test.


RESULTS
Four types of radiographic changes were observed: ground glass (granular/condensed trabeculae), radiolucent (lytic), mixed radiolucent/radio-opaque (mixed density) or radio-opaque (sclerotic). Masking or displacement of the maxillary sinus (range: 77.8-86.4%) and mandibular canal (range: 55.6-75.0%) were prevalent in FD sites. Sixty-three percent of the MAS patients had multiple dysregulated endocrine/metabolic functions, the most common were hyperthyroidism, precocious puberty and renal phosphate wasting. There were no statistically significant associations between radiographic patterns and age, endocrinopathies or renal phosphate wasting.


CONCLUSIONS
Maxillo-mandibular FD images in panoramic radiographs fall within a spectrum of four different patterns. Patients with facial asymmetry and any of these radiographic patterns should be promptly referred for further radiographic tests and endocrine evaluation if MAS is suspected.
Akintoye
S O
SO
Craniofacial and Skeletal Diseases Branch, National Institute of Dental and Craniofacial Research/National Institutes of Health, Bethesda, MD, USA. akintoye@dental.upenn.edu
Otis
L L
LL
Atkinson
J C
JC
Brahim
J
J
Kushner
H
H
Robey
P G
PG
Collins
M T
MT
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D005359:Fibrous Dysplasia, Polyostotic / Q000000981:diagnostic imaging*; D006801:Humans; D006980:Hyperthyroidism / Q000150:complications; D017674:Hypophosphatemia / Q000150:complications; D007674:Kidney Diseases / Q000150:complications; D007684:Kidney Tubules / Q000473:pathology; D008297:Male; D008336:Mandibular Diseases / Q000000981:diagnostic imaging*; D008439:Maxillary Diseases / Q000000981:diagnostic imaging*; D008875:Middle Aged; D010026:Osteosclerosis / Q000000981:diagnostic imaging; D011629:Puberty, Precocious / Q000150:complications; D011862:Radiography, Panoramic