GITAM DENTAL COLLEGE & HOSPITAL

DEPARTMENT OF

ORAL & MAXILLOFACIAL SURGERY

SEMINAR ON

FIBRO-OSSEOUS LESIONS OF THE JAWS & ITS SURGICAL MANAGEMENT

Presented By:

Dr. Sambhav K Vora

II MDS

1

CONTENTS-

Introduction

Classification

Fibrous dysplasia

Cemento-osseous dysplasia

Periapical cemento-osseous dysplasia

Focal cemento-osseous dysplasia

Florid cemento-osseous dysplasia

Familial gigantiform cementoma

Ossifying fibroma

Juvenile ossifying fibroma

Osteoblastoma & osteoid osteoma

Cementoblastoma

Differential diagnosis

Controversies

Conclusion

References

2

FIBRO-OSSEOUS LESIONS OF THE JAWS

INTRODUCTION:. The term FibroOsseous lesions (FOL) has been used for

many years as a general description for a group of tumors and proliferative

disorders, which affect the jaws .They comprise a number of specific clinical

entities in which clinical, radiological and histological features often overlap

causing confusion to both pathologist and clinicians in diagnosis and therapy

A bewildering variety of names have been given to lesions within the FOL

group. These include fibrous dysplasia, osteitis fibrosa cystica, fibrous osteoma,

osseous dysplasia, osteofibrosis, periapical cementoma, and osteoid osteoma.

This multiplicity of names, frequently applied to the same pathological

condition has created confusion with regard to diagnostic criteria and

misunderstanding of individual biological behavior.

Fibro osseous lesions (FOL) refer to a diverse process in which the normal bone

architecture is replaced by fibroblast and collagen fibers containing variable

amounts of mineralized material1.

Fibro osseous lesions of the jaws as a generic term used to describe a number of

apparently different pathologic entities that commonly affect the maxilla,

mandible and other facial bones1.

FOL is a generic designation given to a group of disorders (ranging from

inflammatory to neoplastic) that microscopically exhibit, a connective tissue

matrix and islands / trabeculae of bone. Although the histological appearance

and frequently the clinical and radiological features may be similar for many of

these lesions, they demonstrate a wide range of biological behaviour1.

3

The characteristics used to separate the clinical entities are the symptoms and

the radiographic appearance, both of which are extremely varied. Lesions vary

from small, localized, asymptomatic areas discovered on radiographs to well-

defined lesions that cause expansion of the single bone to a functionally

disturbing or cosmetically deforming enlargement of one or many bones. The

radiographic appearance varies from a large, diffuse, dense ground glass pattern

with indistinct boundaries, to localized cyst like radiolucent lesion to well-

defined solitary or multiple radiolucencies with varying foci of radiopaque areas 1.

This presentation is aimed at reviewing the current knowledge and literature

of clinical, radiological, histological features, differential diagnosis, treatment of

fibro-osseous lesions and controversies related to varios lesions and its

management..

CLASSIFICATION

FIBRO OSSEOUS LESIONS OF JAWS

I. Fibrous Dysplasia

II. Cemento-Osseous Dysplasia.

a) Focal Cemento osseous Dysplasia

b) Periapical Cemento osseous Dysplasia

c) Florid Cemento osseous Dysplasia

III. Familial Gigantiform Cementoma

IV. Ossifying fibroma.

V. Juvenile ossifying fibroma

4

III. Miscellaneous

Osteoblastoma,OsteoidOsteoma.Cementoblastoma,

Charles Waldron’s classification:

I. Fibrous Dysplasia

Monostotic

Polyostotic

II. Fibro Osseous (Cemental) lesions presumbly arising in periodontal ligament.

Periapical Cemental Dysplasia

Localised Fibro Osseous Cemental Lesions (Probably reactive in nature)

Florid Cemento osseous Dysplasia (Gigantiform Cementoma)

Ossifying fibroma and cementifying fibroma.

III. Fibro- Osseous Neoplasm of Uncertain or Debatable Relationship to

those arising in the periodontal ligament.

Cementoblastoma, Osteoblastoma, Osteoid Osteoma.

Juvenile active ossifying fibroma and aggressive active

cementifying/ossifyingfibromas

5

Brannon and Fowler classification 9

1.Fibrous dysplasia

A. Monostotic

B. Craniofacial

C. Polyostotic

D. McCune-Albright syndrome

2. Ossifying fibroma and juvenile ossifying fibroma

3. Osseous dysplasia

A. Periapical

B. Focal

C. Florid

D. Familial gigantiform cementoma

CLASSIFICATION OF RADIOLOGICAL PATTERNS OF THE FIBRO-

OSSEOUS LESIONS OF THE JAWS3

Divided into 3 groups-

6

i. Tumour

ii. Dysplasia

iii. Inflammation

These 3 groups were again divided into 5 types based on their radiographic

patterns-

A. Focal

B. Target

C. Radiolucent

D. Calcification

E. Multiconfluent

7

The importance of radiology to the diagnosis of FOL:

Maxillofacial FOLs are of particular interest to the radiologist because they

emphasize the central role of the radiologist in the diagnostic process. This role

arises because the pathology for all FOLs is identical, although they range

widely in behaviour, from dysplasia, hamatoma to benign neoplasia with

occasional recurrence. The late Charles Waldron wrote “In absence of good

clinical and radiologic information a pathologist can only state that a given

biopsy is consistent with a FOL. With adequate clinical and radiologic

information most lesions can be assigned with reasonable certainty into one of

several categories” Conversely in the absence of such information Eisenberg

and Eisenbud stated that “pathologists today will often rightly decline to render

a definitive diagnosis, Instead, the pathologist will resort to the noncommittal

designation of benign fibro-osseous lesions [their italics]. This is the only

acceptable approach considering the potential for inappropriate treatment

otherwise.” Therefore the identification of the majority of FOLs is made upon

clinical and radiological features Radiological assessment of the anatomical

location of a bone tumour, its shape and size, the pattern of its matrix and its

destruction, the definition of its margins and concomitant softtissue

abnormalities generally correlate with its behaviour (aggressive or benign).

“Periosteal reaction” an important feature considered by skeletal radiologists “is

not a feature of benign fibro-osseous lesions”.

Many FOLs, particularly COD, are symptomless and require no surgery.

Therefore diagnosis of the lesions on clinical and radiological features alone

may obviate the need for an otherwise unnecessary invasive procedure. This

avoidance of surgery could benefit the patient, because exaggerated growth of

FD may be stimulated by surgery in young patients.7

8

Radiological evaluation can be carried out with plain radiography ( P.A view,

lateral view, oblique view or waters projection), OPG, Intra oral periapical

radiograp and Occlusal radiograph. Bitewing radiograph can be useful only in

visualization of supracrestal bone formation, which if present is suggestive of

malignancy such as osteosarcoma or chondrosarcoma.

C. T scans are also excellent for demonstrating many subtle lesions especially

for the evaluation of expansile and destructive processes and also for the

visualization of cortical breakthrough and extraosseous extensions. I.V contrast

administration enhances the soft tissues. Dentascans can also be useful in

diagnosing fibro-osseous lesions.

M.R.I can be useful in differentiating solid from non-solid masses, for ex-

fibrous dysplasia complicated by the presence of Aneurysmal bone cyst.

C.T scan has advantage over MRI In its ability to show the matrix of lesion and

whether it contains fibrous, cartilaginous or calcified tissues. Such information

is helpful in the formulation of clinical differential diagnosis.

FIBROUS DYSPLASIA:

W.H.O (1992), defined Fibrous dysplasia (FD) as a benign lesion, presumably

developmental in nature, characterized by a presence of fibrous connective

tissue with a characteristic whorled pattern and containing trabeculae of

immature bone.

It is a condition in which normal medullary bone is gradually replaced by an

abnormal fibrous tissue proliferation. The mesenchymal tissue contains variable

amounts of an osseous matrix that presumably arises through metaplasia and

consists of only woven bone. THIS DISEASE PRODUCES SOLITARY or

multifocal lesions in which there is arrest of bone development in the woven

9

bone stage with failure to lamellar bone. The resultant fibro osseous tissue is

poorly formed and structurally in adequate.

The precise etiology remains unknown, although various theories have been

proposed. Many authorities accept the premise that fibrous dysplasia represents

a non neoplastic hamartomatous growth resulting from altered mesenchymal

cell activity or defect in the control of cell activity.

Marx and Stern (2003) stated that although the clinical development of FD

becomes apparent between 5 to 15 years of age , it begins in the embryo

with the spontaneous gene mutation or deletion of an intra cytoplasmic

transducer protein responsible for bone maturation .all the daughter cells of

the original aberrant cell will produce immature bone, therefore the earlier

this occurs in embryonic development, the more the widespread will be the

FD.

CLINICAL FORMS OF FIBROUS DYSPLASIA /TYPES

Philip et al (1997) – classified FD in to MONOSTOTIC and

POLYOSTOTIC types, where

Monstotic type of FD is further divided in to three subtypes:

Juvenile

Juvenile, aggressive

Adult

Philip et al(1997) Polyostotic type of FD is divided in to three subtypes:

Craniofacial FD – in which only the bones of craniofacial complex are

affected including the mandible and maxilla.

10

Lichlenstein and jaffe type of FD – in which bones of the skeleton with

café au lait pigmentation.

Albright syndrome type of FD- has a traid of severe polyostotic FD,

café au lait pigmentation and various endocrinopathies.

MONOSTOTIC FIBROUS DYSPLASIA

Monostotic fibrous dysplasia (MFD) is a type of Fibrous Dysplasia, which

involves only one bone.MFD is the most common type of regional deformity.

Waldron et al 8 (1992) classified Monostotic type of FD in to three subtypes:

Juvenile

Juvenile, aggressive

Adult

JUVENILE FIBROUS DYSPLASIA

Philip (1997) In the head and neck area, monostotic juvenile fibrous

dysplasia is the most common type of regional deformity. It is slow growing

regional distortion that enlarges proportionately with the affected bone. The

regional over growth continuous until general body growth ceases in the late

teens or early twenties. An uncommon form known as aggressive juvenile

fibrous dysplasia grows at an ever faster rate producing major, often

grotesque deformity that results in loss of function of the affected bone

Clinical Features:

Seen in 1st and 2nd decades of life

Has equal sex predilection

11

Maxilla is effected more than mandible.

Wood N.K and Goaz P.W (1975) stated that the expansion is smooth and

covered with normal appearing mucosa or skin. Ulceration overlying the bony

enlargement is uncommon but may be seen when the mass disrupts the

occlusion or is traumatized during eating.

The first sign of disease is a gradually increasing painless swelling,

which is not well circumscribed and causes a gradually increasing facial

asymmetry. The enlargement is usually smooth, often fusiform in outline

and is more pronounced buccaly than lingually or palatally. When

maxilla is involved there is usually increased prominence of the cheek

and buccal expansion distal to canine, which may extend to involve the

tuberosity. Maxillary lesions commonly extend locally to involve the

sinus, Zygomatic process, floor of orbit and orbital contents are displaced

in some cases. Where the growth is rapid and extensive there may be

marked swelling of the cheek with exopthalmus and proptosis.

Mandibular lesions occur most frequently in the molar and premolar

regions and if the lower border is involved there may be an obvious

protuberance and increased depth of the jaws.

Radiological features:

It varies with the stage of maturity of the lesion, in early stages the lesion

may be radiolucent becoming radiopaque as more bone is formed. The

mature lesion retains none of the normal architecture of trabecular bone,

having replaced it with abnormal bone that produces a “ground glass” or

“orange peel” pattern on radiographs. There is no line of demarcation

because the lesion blends with surrounding bone. Expansion of the

cortical plates and displacement of tooth roots is common. The

laminadura is usually obscured and cortical plates are thinned.

12

Treatment:

Treatment is pursued only when lesions are cosmetically unacceptable or

interfere with sight, mastication and speech, most lesions of the normal

form of juvenile fibrous Dysplasia do not require treatment until the

patient has reached adulthood. Lesions should not be treated by

radiotherapy in an attempt to halt growth because of the risk malignancy

in later life.

ADULT FIBROUS DYSPLASIA:

It is a rare form that occurs spontaneously in adults. It resembles

ossifying fibroma in many ways and must be separated from it because

the treatment is very difficult.

Clinical features:

Are similar to mature juvenile FD. The affected area presents as an

asymptomatic diffuse expansion of the cortices. Some movement of teeth

with in the area may occur.

Radiological features:

Philip (1997) less homogenous than juvenile FD, exhibits a mixed

radiolucent and radiopaque “cotton – ball” pattern. As with other forms

of disease, individual lesions blend with the surrounding bone .expansion

and thinning of the cortical plates is usually evident.

.

Treatment:

Philip (1997) treatment aspect is different from juvenile FD because it is

not self-limiting. In adults, attempts are made to completely remove

13

smaller lesions and halt the progression of larger ones with continuous

conservative treatment.

POLYOSTOTIC FIBROUS DYSPLASIA

Philip (1997) polyostotic type of FD is divided in to three subtypes:

Craniofacial FD – in which only the bones of craniofacial complex

are affected including the mandible and maxilla.

Lichlenstein and jaffe type of FD – in which multiple bones of the

skeleton with café au lait pigmentation.

Albright syndrome type of FD – has a traid of severe polyostotic FD,

café au lait pigmentation and various endocrinopathies.

Clinical features-

Seen in patients under 40 yrs of age

Females are commomly affected than males

Maxilla is commonly affected than mandible.

In the jaws, pain or fracture is rarely present. The most common

complaint is swelling, often toward the buccal side. On examination,

the tissue overlying the swelling is of normal color. The teeth usually

are not mobile, although in severe cases may be displaced. With

involvement of maxilla, the nose may be appear displaced and may

have nasal obstruction and exophthalmia. In most severe cases of

craniofacial involvement, the patients face may appear significantly

14

asymmetric. The serum laboratory values in FD are usually within

normal limits

Radiographic features:

Radiographic appearance of Fibrous Dysplasia is variable, ranging from a

RADIOLUCENT lesion to a densely radio opaque lesion. The classic

presentation has been described as a homogenous radioopacity with the

numerous trabecular of woven bone imparting “GROUND GLASS”

appearance. A 2nd possible pattern is a radiolucent lesion with patchy, irregular

opacities resulting in a mottled radiographic appearance similar in Pagets

disease. An important distinguishing feature of Fibrous Dysplasia is POORLY

DEFINED clinical & radiographic margins of the lesion.

FD commonly displays an abnormal opacification, which ranges from the very

numerous, small and diffusely distributed opacities [“groundglass” and “peau

d’orange” to sclerosis , classically described as

“cotton–wool”. Different patterns may not only be present in different parts of

the same lesion, but may also depend on whether the film used is “direct

exposure” or “fluorescent screen film”.7

The expansion of FD of the mandible is classically spindle (or fusiform)-shaped

when viewed on a true (axial) occlusal film) or on a posterioanterior

projection of the mandible.

Differential diagnosis-

Ossifying fibroma: FD is well established at the age of 20 years but

ossifying fibroma is seen at an older age. Radiographically OF are well

demarcated, spherical or egg shaped, heterogeneous from the normal bone,

also shows expanded or thinned residual uninvolved cortex and

displacement of the inferior alveolar canal, whereas FD are not

15

demarcated, fusifiorm in shape an homogenous. The radiographs and scans

support the concept advanced by Worth that OF is a disease with in the

bone while FD is a disease of the bone .

Chronic sclerosing osteomyelitis :resembles FD in its diffuse and poorly

demarcated radiographic appearance. It too may occur in teenagers and

preteens, but it is more in adults. However, unlike FD, Chronic sclerosing

osteomyelitis is usually severely and constantly painful: there is frequently

a history of an abscessed tooth, or some other infection and appro[priate

cultures may yield actinomyces and eikenella corrodens

Pagets disease :can be distinguished by its onset on individuals older than

40 years and its incrases alkaline phosphate levels.

Osteosarcoma: may be difficult to distinguish from FD radiographically.

In general osteosarcomas do not remodel but resorb the cortex and expand

outward from the destroyed cortex.

TREATMENT and PROGNOSIS:

Once a jaw lesion is determined to represent fibrous dysplasia, the extent of

skeletal involvement should be investigated lesions of F.D. characteristically

exhibit a period of slowly progressive, persistent growth stabilization or

considerable showing of growth after the onset of puberty often follows.

Lesions that result in functional or cosmetic disability may be treated by

osseous recontouring via a transoral approach. This procedure is generally

initiated following the active growth stage and during the period of stabilization

of disease process. For large lesions involving the midface Weber- Fergussion

approach is good alternative for surgical recontouring procedures.

16

The incidence of Malignant transformation of existing F.D. is regarded as rare <

1%. Some investigators have suggested that the change of developing a

malignancy is greater in pts. With polyostotic form of the disease, some Patients

who have developed malignancy had received Radiation therapy, suggesting

that radiation had a sole in the transformation process. Rapid enlargement of a

lesion or onset of pain suggests the possibility of malignant degeneration. Most

SARCOMAS arising in Pre existing lesions of F.D. are high grade lesions with

Poor Prognosis. These have included Osteosarcomas, fibrosarcomas,

chondrosarcomas, malignant fibrous histiocytomas

CEMENTO – OSSEIOUS DYSPLASIAS:

These disease process defined by specific clinical and pathologic features have

been classified as

CEMENTO OSSEOUS DYSSLASIAS:

- Periapical cement osseous dysplasia

- Focal cemento osseous dysplasia.

- Florid cement osseous Dysplasia.

The precise etiology of these lesions is not known. Most investigators suggest

that the C.O.D are the result of disorders in the metabolism of cells normally

involved in the production of bone and cementum matrices. The aberrant

17

activity of these tissues may be the result of an unusual response to undefined

local factors.

PERIAPICAL CEMENTO OSSEOUS DYSPLASIA:

This peculiar condition characteristically involves the periapical bone at the

apices of teeth with vital, noninflammed pulps. The process involves multiple

teeth, usually the mandibular anterior teeth. Periapical cemental dysplasia most

commonly affects middle aged black women.

Clinical features:

Age: Most patients are between 30-50 years.

Site and Location: Mandible is the commonly affected site and anterior

mandible is the frequently affected location.

Waldron9 (1993) lesions are mostly asymptomatic, discovered when

radiographs are taken for other purposes. Solitary lesions may occur, but

multiple foci are present most frequently

Teeth associated with the lesions are almost invariably vital and seldom

have restorations,

Bone expansion is absent and pain is not a feature.

Teeth are vital, a feature, which distinguishes this condition from apical,

cystic and inflammatory process.

Radiological feature: The lesions are usually detected incidentally on routine

radiographic examinations, as the disease is almost invariably asymptomatic

18

Lesions of this type typically have three distinct stages of development.

(1)Osteolytic

(2)Cementoblastic

(3)Mature

Osteolytic stage: The osteolytic stage is characterized by a circular area of

rarefaction at the apex of the vital tooth. The lamina dura is usually absent in

the apical region of the adjacent tooth. The radiolucent area is well demarcated

from the surrounding alveolar bone and a sclerotic ring may be present,which is

thicker ,more irregular,and more diffuse than the margin of a cystic lesion. The

average lesion is approximately 0.5 to 1cm in diameter during this stage in rare

instances,the lesion may be larger than 1cm, in which case it is most likely that

multiple teeth will be involved. The lesion is usually round when it is smaller

than 1cm;it spreads laterally when it enlarges,eventually losing its circular

configuration.

Cementoblastic stage: The cementoblastic stage is characterized by the

appearance of a radiodense cemental mass towards the centre of the lesion.

Initially, a single mass which develops may be very faint. The radiolucent

component remains prominent. An outer rim of sclerotic bone may be

present,especially if active lysis of host bone is in progress. The radiolucent

zone between the central mass of sclerotic rim is divided into three

radiologically distinct bands. The outer band is the region in which calcific

spherules of cementum-like material are formed. In the intermediate band, one

can see individual calcific spherules coalescing with each other form calcific

massules. In the inner band,

Which is adjacent to the central mass, invidual massules are seen that coalesce

with the central mass.

19

Mature Stage: In the mature stage a single central mass develops. In some

instances the mass develops from the apex of the involved tooth, causing it to

have a crescent shape. The periphery of the mass tends to have a smooth

surface, although it may be irregular or even lobulated as a result of coalesced

massules. During periods of dormancy, the cemental mass is in direct apposition

with the adjacent bone and may be mistaken easily for idiopathic osteosclerosis.

During active periods, an outer radiolucent fibrocemento osseous band and

radiopaque margin of reactive bone reappear. The radiolucent band is usually

millimeters wide; however, it may be as thin as a normal periodontal ligament

space or as wide as 0.5 cm. in some instances, especially on panoramic

radiographs, the lingual aspect of the radiolucent outer rim may appear to

extend up on to the root of a tooth; however, this may represent a projection

artifact. The cemental mass may grow on either side of the root, but it usually

does not attach to the root apex. The outer rim of sclerotic bone is a variable

feature.

Histopathology:

These lesions are usually diagnosed on clinical and radiographic features.

When biopsied, they usually consist of multiple fragments of moderately

cellular, collagenous tissue investing variable amounts of bone and cementum

matrix. The relative amount and degree of mineralization of the matrix

components are variable, largely dependent on the length of time the lesions

have been present and therefore the stage of prognosis. The calcified tissue is

associated with osteoblasts and cementoblasts along the surface and is deposited

in variety of configurations, including trabecular, spherules or relatively

irregular masses.

20

Treatment and Prognosis:

Requires no definitive treatment following diagnosis only periodic observation

is necessary during which time one would expect to see the radiographic

changes association with maturation of the lesions.

FOCAL CEMENTO – OSSEOUS DYSPLASIA:

It is a recently described entity that is thought to fall between P.C.D. and florid

osseous dysplasia in the biologic spectrum of C.O.D.

Clinical features:

(1) Most common in females and a higher incidence in whites.

(2) Lesions are typically solitary involving the bone in POSTERIOR

MANDIBLE.

(3) Characteristically asymptomatic and frequently discovered during routine

radiographic examination.

(4) Most lesions are MIXED radiolucent – radio opaque areas, although the

radiographic appearance may very from well defined radiolucent lesion to a

densely radio opaque area.

(5) Most of lesions < 1.5 cm in size

(6) Many cases involve bone adjacent to the roots of asymptomatic vital teeth.

(7) Some cases of F.C.O.D. have been associated with development of

idiopathic bone cavities.

Histopathology:

21

(1) Characteristic feature of F.O.D. is consistency of tissue removed during

biopsy. The tissue is often difficult to correct from the lesion and is removed as

multiple fragments of gritty tissue this feature is especially helpful in distinction

of Ossifying fibroma which can be removed / separated easily from adjacent

normal bone.

(2) These fragments are associated with surgical hemorrhage.

(3) Soft tissue consists of cellular proliferation of fusiform, spindled cells in a

collagenous stroma.

(4) Small blood vessels observed.

(5) Connective tissue consists of small, irregular trabecular of woven bone and

globular deposits of cementum like matrix.

Treatment and Prognosis:

As lesions exhibits only limited potential for progressive growth, most lesions

require no additional treatment.

FLORID CEMENTO OSSEOUS DYSPLASIA:

This disease process represents the most clinically extreme end of the spectrum

of disorders classified as cemento – osseous dysplasias.

Clinicalfeatures:

Most patients who develop F.O.D. are adult, black women. The disease process

characteristically alters he normal bone pattern in a generalized, bilateral

faction.

FOD typically produces mottled, mixed radiolucent radioopaque lesions

adjacent to the teeth through out the affected portions of the jaws. As the

22

lesions mature over time, they may consist predominantly of irregular, diffuse,

sclerotic masses. Uncomplicated lesions of FOD may produce mild cortical

expansion but are otherwise complicated. However, the altered bone is

susceptible to the development of Osteomyelitis following traumatic episodes

such as extractions or biopsies or from mucosal ulcerations such as those

resulting from ill fitting removable prosthesis.

Treatment and Prognosis:

It is a non-neoplastic, self limited process that requires no treatment following

diagnosis. In fact, owing to the significant alterations in the affected bone any

form of trauma, including a biopsy procedure is best avoided.

FAMILIAL GIGANTIFORM CEMENTOMA:

• This is a disorder of jaw bones that ultimately leads to the formation of

massive sclerotic masses of disorganized mineralized material.

• In the past it was a synonym for florid COD.

• It is an uncommon hereditary disorder that demonstrates high penetrance

& variable expressivity.

• It is different from conventional cemento osseous dysplasia.

Clinical features

23

• Commonly seen in caucasians and african blacks, no sex predilection.

• The osseous pathosis appears to be limited to the jaws but multifocal

involving both maxilla and mandible.

• Rapid and expansile growth pattern of jaws in adolescence results in

facial deformity, impaction, malposition, and malocclusion of the

involved dentition.

• Anemia, multifocal polypoidal adenomas of the uterus may be present –

gynocologic consultation is required.

• The osseous enlargement ceases during fifth decade.

Radiographic features

• Resemble cemento osseous dysplasias.

• Initially they appear as multiple radiolucencies in the periapical regions.

• The affected sites expand and develop mixed radiolucent and radiopaque

pattern.

• With further maturation, they become predominantly radiopaque with a

thin radiolucent rim.

Histopathologic features

• It shows same spectrum of changes seen in the florid cemento oseeous

dysplasia, the two cannot be distinguished radiographically.

Treatment and Prognosis

24

• Shave down surgical procedures at the earlier stage to improve aesthetics

are not successful due regrowth.

• At the later stage (radiopaque) partial removal of affected bone will result

in sequestration of the remaining affectd bone.

• Extensive resection and reconstruction of the lesion is recommended at a

later stage if they are causing significant functional & esthetic deformity.

• The extent of surgical procedures is greater at a later stage.

OSSIFYING FIBROMA:

It is considered by most to represent a benign neoplasm arising from

undifferentiated cells of periodontal ligament tissue. This lesions has been

referred to as osteofibroma, fibro-osteoma and benign fibro-osseous lesion of

Periodontal ligament origin. In 1972, the World HealthOrganization (WHO)

considered ossifying fibroma to be a tumor of bone origin This lesion shares

identical clinical radiographic and histopathologic features of with cementifying

fibroma. Neoplastic etiology for ossifying fibroma includes persistent, locally

aggressive growth characteristic and finding of recurrence is seen. Some

investigators regard the lesion as example of localized dysplastic process in

which bone metabolism has been altered.

Clinical features:

It is typically a slow growing, expansible lesions that replaces normal bone as it

enlarges.

25

Most lesions are asymptomatic when detected with rare exceptions, lesions arise

in tooth bearing regions of jaws, with the body of mandible being the most

common site.

Most affected patients are adults with peak incidence between 20 and 40 years.

A definite female predominance (5:1).

When lesions remains undetected for a period of time, the lesion exhibits slow

but persistent progression, in gradual expansion and possible thinning of buccal

and lingual cortical plates.

Firbromas occur as solitary lesions.

In contrast to fibrous dysplasia, the most important distinguishing feature is well

circumscribed sharply defined border between lesion and adjacent bone.

Early lesions present as unilocular or multilocular radiolucencies. It progresses

gradually to a mixed radiolucent radiopaque stage and matrix material is

deposited and mineralized in the lesion.

Fully mature, long standing lesions appear as dense, radiopaque masses

surrounded by a thin, well defined regular, radiolucent rim.

As lesions enlarge, they may displace adjacent teeth and less commonly cause

resorption of tooth roots.

Histopathology:

The tumor consists of a collagenous stroma containing variable number of

uniform spindled or stellate cells. Collagen fibers are often arranged

haphazardly.

The degree of vascularity is variable some are relatively avascular and fibrotic,

whereas others exhibit a well vascular stoma.

26

Irregular partially interconnecting trabecular of woven bone are noted.

Presence of OSTEOBLASTS along the surface of bone deposits.

Basophitic spherical calcifications and anastamosing trabecular of cementum

like material are also frequently present.

Differential diagnosis-

1. Fibrous dysplasia-

S.No Fibrous dysplasia Ossifying fibroma

1. Site- common in maxilla Common in mandible

2. Seen at 1st and 2nd decade 3rd and 4th decade

3. Equal sex predilection Females are commonly

affected

4. Radiologically no line of

demarcation between normal

bone and immature bone

Line of demarcation seen

( encapsulated neoplasm)

5. Fusiform elongation or

expansion

Round or oval expansion

6. Histologically only woven

bone will be seen

Lamellar bone will also be

seen.

2. Osteoid osteoma and osteogenic sarcoma- gives an ill defined aggressive

appearance with radiographic signs of malignancy.

27

3. Condensing osteitis and focal sclerosing osteomyelitis- lacks the

surrounding radiolucent capsule seen in ossifying fibroma and thus easily

differentiated.

4. Ameloblastoma – multilocualated, bubbly appearance, clear line of

demarcation present, root resorption may be present. Sometimes even

associated with unerupted tooth.

5. Adenomatoid odontogenic tumour-

Treatment & Prognosis:

An intraoral approach for the surgical excision of tumor by enucleation is the

preferred method of management adjacent normal structures including teeth,

neurovascular elements and bone should be preferred whenever possible when

large lesions are excised and potential risk for postoperative fracture, IMF

should be considered during initial healing stages. In extensive lesions surgical

resection and bone grafting is indicated.

Cryotherapy is also indicated in treating ossifying fibroma for conditions which

are lying adjacent to the bone or lying within the bone.1

JUVENILE OSSIFYING FIBROMA:

• Synonyms: juvenile aggressive ossifying fibroma, juvenile active

ossifying fibroma and aggressive psammomatoid ossifying fibroma.

• The term active juvenile ossifying fibroma is considered when the lesion

behaves in the more aggressive manner & the patient is under the age of

15 years. Recurrences rates of around 30 to 50 % are encountered in this

type of lesion.2

28

• This uncommon lesion is distinguished from standard OF based on

– its more clinicaly aggressive biologic behaviour,

– occurrence in younger age group,

– and tendency to occur in different anatomic sites.

Clinical features

• Most cases reported before the age of 15 yrs.

• The most frequent sites of occurrence include the orbital ,frontal and

ethmoid bones, the paranasal sinuses, and the maxilla.

• In contrast to standard OF mandible is less frequently involved.

• Common clinical presentation are proptosis, exophthalmos, visual

disturbances, nasal obstruction and facial asymmetry.

• Many tumors exhibit rapid and progressive enlargement.

• Some lesions produce expansion and thinning of cortices; others may

erode the bone and adjacent soft tissue spaces.

• Intra cranial extension through cribriform plate leading to elevation of

frontal lobe and pneumococcal meningitis is also reported.

Radiographic features

• Most tumors present as destructive, expansile lesion, often with fairly

well demarcated, even corticated, borders.

29

• Frequently the lesion exhibits a primarily radiolucent quality with varying

amounts of internal radiopacity, reflecting the degree of mineralization.

Histopathologic features

• Microscopic findings of this lesion are controversial.

• The tumor stroma consists of a highly cellular proliferation of spindled to

stellate cells with minimal intervening collagen.

• The cellular stroma invests thin strands and cords of osteoid, which

contain many osteocyte like cells.

• It also contains woven bone trabeculae with osteoblastic rimming.

• Some lesions contain numerous unoiform, round often laminateds

tructures described as ossicles or psammoma like bodies.

• Other features include –multinucleated goiant cells, myxoid stromal

altterations with areas of degenration, and pseudocyst formation.

Treatment and Prognosis

• The approach to surgical treatment is continually evolving.

• Complete surgical excision is the goal, taking into consideration the size,

location, and extent of the tumor.

• Small accessible lesions may be amenable to surgical excision with

enucleation alone or with peripheral ostectomy.

• Reported recurrence rates for this tumor is between 30% and 58% but no

evidence of metastasis.

30

• Larger, recurrent lesions may necessitate segmental resections and

reconstruction with bone grafts.

OSTEOBLASTOMA AND OSTEOID OSTEOMA:

Osteoblastoma and Osteiod Osteoma are recognized neoplasms in the

extragnathic skeleton and have been occasionally been reported in the jaws.

There is wide agreement that Osteoblastoma and Osteoid Osteoma are closely

related lesions and are separated only on the basis of their clinical and

radiologic characteristics. Some authorities prefer the term Osteoblastoma for

both lesions.

The radiographic findings in Osteoblastoma of the jaws and the remainder of

the skeleton are quite inconsistent and showing varying combinations of

radiolucency and calcification that sometimes are indistinguishable from typical

ossifying/ cementifying fibromas.

Histologically, osteoblastomas can show a range of features, but most typically

they have a highly vascularised stroma containing irregular, frequently

anastomosing trabecular of Osteoid and immature bones with varying decrease

of calcification. The osteoid trabecular are surrounded by prominent, plump

osteoblasts and similar osteoblast like cells are conspicuos in the inter trabecular

spaces. Varying number of multinucleated giant cells may also be present.

Although the histologic findings in the usual osteoblastoma are fairly

distinctive, they have enough overlapping features with some ossifying

fibromas so that the designation of a given lesion as an Osteoblastoma or an

ossifying fibroma may be constroversial.

CEMENTOBLASTOMA:

31

Clinical and Radiographic features:

• It is a odontogenic neoplasm of cementoblasts

• And also known as true cementoma.

• These are rare, less than 1 % of all odontogenic tumors.

• The most common site is posterior mandible that too first molar area

(50%).

• No sex predilection, rarely affects deciduous teeth.

• The common age group is 10-30 yrs.

• Pain and swelling may be present.

• Radiogrphically it appears as a radiopaque mass that is fused to one or

more tooth roots and is surrounded by a thin radiolucent rim.

• The outline of the roots of involved tooth is usually obscured as a result

of root resorption and fusion of tumor with the tooth.

Histopathologic features

• It resembles osteoblastoma and only difference is fusion of the tumor

with the root.

• It consists of sheets and thick trabeculae of mineralized material with

irregularly placed lacunae and prominent basophilic reversal lines.

• Cellular fibrovascular tissue surrounds the trabeculae, and giant cells are

often present.

32

• The periphery of the lesion corresponding to the radiolucent zone seen on

the radiograph, is composed of uncalcified matrix, which often is

arranged in radiating columns.

Treatment and Prognosis

• Surgical extraction of the tooth together with the attached calcified mass.

• Surgical excision of mass with root amputation and endodontic treatment

of the involved tooth may also be considered.

• The prognosis is excellent, tumor does not recur after removal.

• Progressive growth of the tumor after extraction of the tooth and

incomplete removal of the mass has been documented.

According to Eversole et al, the histopathological features of the benign fibro-

osseous process, and radiographic findings, such as evidence of bone cortical

expansion and well-defined margins, suggest the diagnosis of non-aggressive

OF, type B. However, the radiographic features seem to make a modest

contribution to the diagnosis of hybrid lesions, as indicated by the small number

of cases reported in the literature. In addition, Central giant cell granuloma

fundamentally presents radiolucent images, especially in lesions with huge

dimensions. It is recognized that CGCG may produce calcified material.

33

We emphasize that the CT images revealed the localization, nature and extent of

the lesion. The last feature seems to be present in all the cases reported. The

images led to a diagnosis of OF, and the anatomopathological examination

confirmed an association of CGCG and a fibro-osseous lesion. 7

Differential diagnosis of fibro-osseous lesions –

Radiolucent lesions-

a. Unicystic radiolucency with sclerotic margin-

1. Cyst- radiolucency will be smooth, thin and sharply defined. Tooth

will be vital and aspiration shows positive response.

b. Unilocular radiolucency without sclerotic margin with ill defined margins

should be differentiated with malignancies. Root resorption will also be

seen in all malignant lesions.

c. Multilocular radiolucent lesion-

Locules of trabeculae might be few in number and of poor density like

central giant cell granuloma or it may be coarse and thick resembling like

ameloblastoma.

Chronic osteomyelitis should also be considered as differential diagnosis.

Mixed radiolucent and radioopaque lesions-

1. Periapical cement osseous dysplasia- radiolucent lesion surrounds the

apex of the tooth, with either sclerotic margin or opaque masses within

the lucent lesion. Tooth will be vital, absence of pain, no expansion of

cortices.

34

2. Malignant metaststic lesions like osteogenic sarcoma and osteoblastic

carcinoma appears as mixed radiolucent – radioopaque lesions but they

are usually irregular and ill defined along with root resorption which is

not seen in fibro-osseous lesions.

3. Odontoma- it is usually located above the crown of an unerupted tooth

and seldom it is found in the apical region . these are more radioopaque

compared to fibroosseous lesions.

4. Fibrous dysplasia- common in maxilla, seen in 1st and 2nd decade of life.

Has equal predilection for both male and female. Jaw expansion is seen

which is of fusiform type. there is noline of demarcation between

normal bone and defective bone.

5. Condensing osteitis- clinically pain, inflammation, drainage, tenderness

on palpation and regional lymphadenitis will be present.

6. Cement-ossifying fibroma- predilection for premolars and molars. Seen

under 30 years . Attains size of 2 to 4 cm, produces discernible

expansion.

Mixed radiolucencies and radioopacities not necessarily contacting

teeth-

1. Fibrous dysplasia

2. Chronic osteomyelitis

3. Cement-ossifying fibroma

4. Pagets disease

5. Chondrosarcoma

35

Radio-opaque lesions-

1. Fibrous dysplasia

2. Focal sclerosing osteomyelitis

3. Diffuse sclerosing osteomyelitis

4. Focal cement-osseous dysplasia.

CONTROVERSIES

Despite the many years of dedicated study by numerous investigators, the

concepts and parameters of fibro-ossoeus diseases are still in flux.

Among the new theories and contentions, there is now essential agreement that

the osseous dysplasias represent a single disease process, while the so-called

juvenile active ossifying fibroma and other aggressive, active, psammomatoid

ossifying/cementifying fibromas remain controversial2

Are fibro-osseous lesions malformations, hamartomas, or neoplasms?

36

It is strange that fibrous dysplasia, cemento-ossifying fibromas are

considered as fibro-osseous lesions not neoplasms and Osteoid osteoma

and osteoblastoma are considered as neoplasms and not fibro-osseous

lesions.

The debate as to tissue of origin is of little clinical significance, as long as one

differentiates ossifying fibromas from fibrous dysplasia. Hamner et al

advocated the periodontal origin of ossifying fibroma. The periodontal ligament

has been shown to be capable of producing cementum and osteoid, both of

which are characteristically found in ossifying fibromas. Krausen et al and

Spjut et al, however, postulated that primitive mesenchymal cells in areas such

as the ethmoid bone and long bones may produce cementum at sites distant

from odontogenic tissue. They discredited the notion that these tumors arise

from ectopic periodontal tissue in these locations.

.

37

The major controversies are:

1. Distinguishing various fibro-osseous lesions among themselves and

also with other neoplastic lesions.

2. Surgical management of this lesions also remain controversial as to

treat such lesions aggressively initially only or should wait for its

transformation into malignancy then en bloc resections should be

planned. Some lesions can only be treated by curetting and

enucleating.

3. Identifying and predicting aggressive lesions histologically

CONCLUSION

• FOLs are diverse group of processes and benign in nature.

• Diagnosis involves all aspects of the disease like clinical, radiographic,

and histopathological features.

• Histopathology of FOLs is similar, and confusing.

• Treatment largely depends on extent of esthetic and functional deformity.

REFERENCES

1.A.E. Abdullai, Benign fibro-osseous lesions of the facial skeleton: analysis of

52 cases seen at the korle bu teaching hospital. Ghana medical journal sept

2004;vol38: no 3

2. Alper Sari, Juvenile ossifying fibroma: report of a case. Gazi Medical Journal

2001;12:62-71

3.. ARAKI MASAO Classification of Radiographic Patterns of Fibro-osseous

Lesions in the Jaws Dental Radiology VOL.43;NO.3;PAGE.121-129(2003).

4. Brannon, Robert B.; Fowler, Craig B Benign Fibro-Osseous Lesions: A

Review of Current Concepts Advances in Anatomic Pathology:

May 2001 - Volume 8 - Issue 3 - pp 126-143

5. CA. Waldren , Fibro-osseous lesions of the Jaws, JOMS,1985; 43:249-62.

6. CA. Waldren ,Fibro-osseous lesions of jaws, -, JOMS, 1993.

38

7. D.S. MacDonald-Jankowski, Fibro-osseous lesions of the face and jaws.

Clinical Radiology (2004) 59, 11–25

8.D.Summerlin, Diagnosis of fibro-osseous lesions of the jaw . JOMS ;64(9):1

9. Faizan Alawi, DDS, Benign Fibro-osseous Diseases of the Maxillofacial

Bones. Am J Clin Pathol 2002;118(Suppl 1):S50-S70

10. Fibro osseous lesions- Dental clinics of North America

11. Maxillo facial surgery- Peter Ward Booth

12. Necdet DOĞAN, Fibro-Osseous Lesions of the Jaws:

Report of Three CasesTurkiye Klinikleri J Dental Sci 2007, 13:146-152

13. Oral and maxillofacial surgery - Daniel M Laskin

14. Surgical pathology - Fonseca vol. 5.

15. TB of Differential diagnosis –Wood and Goaz

16. TB of Oral and maxillofacial pathology – Brad Nivelle

17. TB of Oral pathology - William Shafer

39

.

1. .

40