fibro osseous - lesions of the cranial and facial bones are usually benign and 
 tend to grow slowly . benign fibro - osseous lesions have similar 
 histopathological features with fibrous dysplasia , ossifying fibroma , 
 and cemento - ossifiying dysplasia . ossifying fibroma , a rare tumour entity , is a well - demarcated benign 
 fibro - osseous tumour with capsule composed of metaplastic bone , fibrous 
 tissue and varying amounts of osteoid . conventional ossifying fibromas are usually 
 slow growing and generally seen in the third and forth decades of life 
 . it affects people of all ages , but in contrast to the form seen at 
 adults , the juvenile form is clinically more aggressive and tends to be 
 recurrent . according to the new edition of the classification of the world health 
 organization , ossifying fibromas which appear as fast growing mass 
 between 5 and 15 years of age , radiologically well bordered , and 
 consistent with ossifying fibroma histologically , juvenile ossifying fibroma ( jof ) appears at an early age and in 79% of 
 the patients are diagnosed before the age of 15 . the jof is located mainly ( 85% ) in facial bones , in 
 some cases ( 12% ) in calvarium and very seldom ( 3% ) extracranially . ninety percent of the lesions located in the face region , involve the 
 sinuses , mainly the maxillary antra . it appears locally 
 aggressive with cortical disruption and involvement of many adjacent 
 anatomical structures . this lesion has predominating soft tissue 
 consistency with variable amounts of internal calcification and/or 
 linear or irregular focal bone . it usually shows a low density mass 
 due to cystic changes on computed tomography ( ct ) scans . following 
 intravenous injection of iodinated contrast , the lesion may show diffuse 
 appearance enhancement . magnetic resonance imaging ( mri ) is important for the lesion extent evaluation , but is inadequate for 
 bony components . histologically , jof is characterized by the presence of cellular fibrous 
 strom , garland like bony strands and cement particles . the jofs are classified into two distinct clinicopathological entities : the 
 trabecular and the psammomatoid types . trabecular jof is distinguished 
 by the presence of trabeculae of fibrillar osteoid and woven bone and 
 psammomatoid jof is characterised by the presence of small uniform 
 spherical ossicles that resemble psammoma bodies . psammomatoid jof occurs predominantly in the 
 sinonasal and orbital bones , and trabecular jof predominantly affects 
 the jaws . psammomatoid jof has aggressive behaviour and it has a very 
 strong tendency to recur . an accurate diagnosis of jof is made by correlating the clinical , ct scan , 
 mri and histopathological findings . authors herein presents a case 
 of juvenile ossifying fibroma of the mandible which caused expansion and 
 destruction of mandibular cortex . a 9 year old girl applied to the department of otorhinolaryngology and head 
 & neck surgery , seluk university , konya , turkey , complaining of a 
 swelling on the right side of her lower jaw lasting three months . she 
 also felt a pain and inflammation in this area . medical history revealed 
 acute lymphocytic leukaemia presented in remission for 3 years . physical examination revealed a hyperaemic swelling about 6 x 8 cm in 
 size , causing facial asymmetry in the region of submandibular area 
 including right corpus and ramus of the mandibule ( figure 1 ) . assessment 
 with palpation showed a hard , nontender mass with smooth surface adhered 
 to the mandible . the mouth opening of the patient was normal and there 
 were no decayed teeth in the lesion area , but there was malocclusion . there were no assessed pathological changes of the mucous membrane in 
 the tumour region . photograph of a 9 year old girl with jof showing unilateral 
 swelling extending from the right submandibular to the right 
 mandibular ramus and corpus region . photograph of mandibular ramus and corpus region 
 showing clear lingual expansion of the mansoble ( arrow ) . panoramic radiograph showed an irregular but well bordered , unilocular , 
 expansive lesion of the right corpus and ramus of mandible . the ct scan of mandibular tumour showed a solid hypodense mass that enlarged 
 the submandibular area , filled the pterygoid fossa and right masseter 
 muscle region . the tumour was occupied and destructed the right corpus 
 and ramus of the mandible ( figure 3 ) . ct axial image shows a lesion involving submandibular area and 
 causing expansion and destruction of body and ramus of the right 
 mandible ( arrow ) . the heterogenic mass lesion caused destruction of the right ramus of 
 mandible was seen on mri . it was hypointense on t1-weighted images and 
 hyperintense on t2-weighted images ( figure 4 ) . pharyngeal air column , 
 hyoid bone and larynx were displaced to the opposite side ( figure 5 ) . mri axial image shows a large tumour which causes destruction of 
 body and ramus of the right mandible ( arrow ) . mri coronal image shows contrast retention in the tumour ( arrow ) 
 after gadolinium injection . the incisional biopsy was taken from the lesion and the pathology process 
 was reported as jof . diagnosis was based on the presence of trabeculae 
 of fibrillar osteoid and woven bone fragments ( figure 6 ) . because of 
 large size of the mandibular tumour , the resultant expansion and 
 destruction of mandibular cortex , and the close adjacency to the 
 temporomandibular joint , the patient underwent a right hemimandibulectomy using transmandibular approach ( figures 7,8,9 ) . no recurrence was observed during the 2 years of follow - up with three dimensional ct scan and mri ( figures 10 and 11 ) . oral functions of 
 the patient ( chewing , eating and speaking ) were appearing intact ( figure 
 12 ) . photomicrograph of tumour shows the presence of trabeculae of 
 fibrillar osteoid and woven bone ( hematoxylin 
 and eosin stain , original magnification x40 ) . photograph of gross surgical specimen of about 13 x 8.5 x 6.5 cm 
 in size . three - dimensional ct scan shows good jaws relationship and 
 occlusion in the left side . moreover , an unusual clinical presentation with apparent 
 aggressive and destructive growth may be expected when the lesion is 
 encountered in a younger patient , especially below the age of 15 years 
 . it is 
 also called aggressive ossifying fibroma due to its aggressiveness and 
 the high tendency to recur , unlike other fibro - osseous lesions , such as 
 cemento - ossifying fibroma , which may resemble radiographically . due 
 to its distinct histological features , jof has been recognized as a 
 separate histopathological entity among the fibro - osseous group of 
 lesions . jof is a relatively rare fibro - osseous lesion of the jaws characterized by the 
 early age of onset i.e. , under 15 years of age , the location of tumour , 
 and the radiological appearance and the tendency to recur . in contrast , johnson et al .   stated that mandibular tumours are more frequently common in girls between the age of 5 - 11 or 
 during the second to fourth decades of life . a few cases of facial trauma have been suggested as a possible etiologic 
 factor in the jof development . there was no trauma in anamnesis of 
 present patient , but there was an abscess previously drained from this 
 area . noffke   after 8 year follow - up of a juvenile ossifying fibroma in the left 
 mandible of a 4 year old boy demonstrated initial lack of radiological 
 evidence of demarcation and subsequent eccentric enlargement , selective 
 tooth displacement and a multilocular appearance in areas of active 
 growth . additionally , an aneurysmal bone cyst and a decrease in the bone 
 content were presented in the excision specimen . furthermore , 
 osteblastoma , osteosarcoma and odontogenic tumours should be considered 
 in the differential diagnosis of jof . while the osteoblastoma is 
 radiologically seen as cystic bone lesion with sclerotic boundary , 
 abnormal soft tissue mass and aggressive bone destruction is seen in the 
 osteosarcoma , and cystic lesion connected to premolar or molar teeth is 
 seen in odontogenic tumours . the jof is characterized as expansive , having defined sclerotic borders , locally 
 aggressive and destructive at cortex on ct scan . this lesion is observed 
 as a soft tissue mass with internal calcification , linear or irregular 
 bone focuses . while aggressive cortical changes are 
 seen in juvenile form , sclerotic changes are more common in adult form 
 . following gadolinium injection , a slight increase in contrasting is seen 
 . in present case , the lesion was hypointense in t1 and 
 hyperintense in t2 on mri and there was clear contrast retention after 
 the injection of contrast agent . these findings suggest that there was 
 acute lymphocytic leukaemia in the patient 's history . however , after the 
 incissional biopsy obtained from the lesion the final diagnosis of jof 
 was recognized . ong and siar   presented jof as a progressively growing lesion that can 
 attain an enormous size with resultant deformity if left untreated . they 
 presented a case of large cemento - ossifying fibroma involving the left 
 mandible in a 15 year old male patient . furthermore , 
 if jof do not have adequate surgical treatment , it may have high rate of 
 recurrence . the recurrences are generally seen at early stage and they are more aggressive when compared to primary lesions . radical resection , local 
 excision conservatively or enucleation with curettage are among the 
 treatment alternatives . slootweg and mller   suggested 
 that there were no differences between the cases that have limited 
 surgical treatment and those with major surgery in terms of results , and 
 they recommended conservative surgery . on the other hand , waldron et al . 
  suggested that local excision and curettage should be a more 
 preferable method and added that local surgical excision can be applied 
 for recurrent tumour treatment . however , rate of recurrence after 
 conservative treatment was reported in 30 - 58% of cases . therefore , 
 some authors were recommended en block resection as an adequate 
 treatment . curettage together with peripheral osteotomy or sometimes segmental 
 mandibular resection and mandibular reconstruction are suggested in 
 prevalent or recurrent cases . sarcomatous degeneration is reported 
 to develop in lesions that have recurrence in long term . in contrast , espinosa et al .   reported a case of unusual bone 
 regeneration after resection of jof . secondary mandibular reconstruction 
 with autogenous grafts was delayed due to the rapid bone formation . because the large size of the mandibular tumour , resultant expansion and 
 destruction of mandibular cortex , the patient underwent right 
 hemimandibulectomy using transmandibular approach . performed resection and reconstruction keeping 
 the mandibular tissue around the temporomandibular joint . however , in 
 present case , it was necessary to perform right hemimandibulectomy due 
 to close localisation of the tumour to the tempormandibular joint and 
 absence of adequate reliable surgical border . despite of there was no 
 recurrence or complication during two years of follow - up period . although juvenile ossifying fibroma is an uncommon clinical entity , its 
 aggressive local behaviour and high recurrence rate mean that it is 
 important to make an early diagnosis , apply the appropriate treatment 
 and , especially , follow - up the patient over the long - term .
abstractbackgroundfibro - osseous lesions of the jaws , including juvenile ossifying fibroma , 
 pose diagnostic and therapeutic difficulties due to their clinical , 
 radiological and histological variability . 
 the aim of this study was to 
 report the outcome of a 9 years old girl with diagnosed juvenile 
 ossifying fibroma treatment.methodsa 9 years old girl presented with a 6 x 8 cm sized hard fixed tumour on 
 right ramus and corpus of the mandible . on the radiological examination 
 tumour showed an irregular but well bordered , unilocular and expansive 
 lesion on the right corpus and ramus of the mandible . 
 there was no teeth 
 displacement or teeth root resorbtion . 
 microscopically , the tumour had 
 trabeculae , fibrillary osteoid and woven bone . after the clinical , 
 radiological ( panoramic radiography , computed tomography and magnetic 
 resonance imaging ) and histologic analysis it 
 was diagnosed juvenile 
 ossifying fibroma . in the history of the patient 
 there has been an acute 
 lymphocytic leukaemia in the remission for 3 years.resultsbecause of large size of mandibular tumour , resultant expansion and destruction 
 of mandibular cortex , the patient underwent right hemimandibulectomy 
 using transmandibular approach . 
 there was no recurrence or complications 
 for two years follow-up.conclusionsalthough juvenile ossifying fibroma is an uncommon clinical entity , its 
 aggressive local behaviour and high recurrence rate means that it is 
 important to make an early diagnosis , apply the appropriate treatment 
 and , especially , follow - up the patient over the long - term .