Differiential diagnosis of maxillary sinus pathology

Department of oral medicine and radiology

Differential diagnosis of maxillary sinus pathology

Submitted by,

Shiji Margaret

Final BDS

CONTENTS1. INTRODUCTION2. CLASSIFICATION3. ETIOLOGY4. PATHOGENESIS5. CLINICAL FEATURES6. RADIOLOGICAL FEATURES7. DIAGNOSIS8. TREATMENT9. COMPLICATION10. REFERENCE

1

INTRODUCTION

The paranasal sinuses are air filled cavities present with some bone around the nasal cavities. The sinuses are frontal,maxillary,sphenoid and ethmoidal. Because of the close proximity of maxillary teeth with the maxillary sinuses, these are the most important paranasal sinuses in dental point of view. They are the largest air filled sinuses surrounding the nose.

Embryology

It is the first among the paranasal sinuses to develop.

It starts as a groove on the medial surface of the maxilla during the 4 th month of intrauterine life

At birth,it is a small cavity which is usually fluid-filled. Growth is usually biphasic with growth occurring during the age of 0-3 years and again between 7-12 years. It attains its maximum size at adulthood at around 18years of age. During the later phase pneumatisation proceeds more inferiorly as the permanent teeth develop completely

Anatomy of maxillary sinus

Maxillary sinus is also called “antrum of highmore” This structure is closely related to oral cavity and lesions/infections of the maxillary antrum may present in the oral cavity and vice versa.

2

Arterial supply

Facial artery,infraorbital artery. Greater palatine artery.

Nerve supply

Infraorbital nerve;anterior,middle and posterior superior alveolar nerve

Venous drainage

Facial vein which then drains into pterygoid venous plexus.

Lymphatic drainage

Submandibular lymph nodes and then to deep cervical lymph nodes.

Classification

1. Inflammatory Acute and chronic sinusitis Mucositis Antral polyp Osteomyelitis

2.cyst

Intrinsic Mucus retention cyst(mucocele) Pseudo cyst Surgical ciliated cyst

Extrinsic Odontogenic

Radicular Primordial

3.Neoplasm

Non-odontogenic Exostosis Enostosis

Malignant Squamous cell carcinoma Midline lethal granuloma

4. Developemental

Crouzon syndrome Treacher Collin’s syndrome Binder syndrome

5. Calcification

Anthroliths

6. Traumatic

Fracture of maxilla, tuberosity, nasal bone, zygoma and orbital floor

– Blow out fracture– Isolated injury– Complex fracture

Hematoma due to traumatic injury Foreign bodies displace into the sinus- fractured

tooth/root Oral antral fistula Sinus contusion

Inflammatory disease

Acute and chronic sinusitis

Inflammation of the mucosa of the paranasal sinuses is referred to as sinusitis.when maxillary sinus is involved, it is called as maxillary sinusitis.when all the sinuses are involved it is called as pansinusitis.

Etiology

Dental causes

Periapical infection from the teeth: it may follow dental infection particularly from upper molars and premolars teeth

Oroantral fistula: the accidental opening in the floor of the maxillary sinus during dental extraction is called as oroantral opening.

Periodontitis: it may spread from a deep pocket of marginal periodontitis.

Traumatic: injury of facial bones especially nasal bones and malar bones

Dental material in the antrum: perforation of endodontic filling substance. If root canal is overfilled then there are more changes of gutta purcha points to be inserted into the maxillary sinus.

Implant: implants are used in upper edentulous jaw to aid the retention of dentures or bridges or replace missing teeth.implants are also used when there is insufficiency of bone to support the denture.in these cases as bone is thin,implant can penetrate the nose or sinus.

Infected dental cyst: cyst which have become infected and involve the maxillary sinus can also cause sinusitis

Non-dental causes

Mechanical obstruction of ostium Common cold Allergic rhinitis Other condition

Direct bacterial contamination: infected material may also be introduced directlyby jumping or hydrosliding feet first into contaminated water without holding the nose or during diving,when pressure changes in the nose force nasal secretion into sinus.

Immune deficiency: sinusitis can occur in immune deficiency, state like leukemia,lymphoma and AIDS

Influenza: it can also occur in influenza when bacteria invade as secondary microorganisms.

Blood brone infection: it can also occur in some cases of blood brone infection

Disease of maxillary sinus: benign mucosal cyst or tumors of maxillary sinus can also lead to maxillary sinusitis.

Clinical features

Acute sinusitis: this is a complication of common cold and is accompanied by clear nasal

discharge or pharyngeal drainage,which may eventually become green or greenish-yellow colored.

After a few days the stuffiness increases and the patient complaints of pain and tenderness to pressure or swelling over the involved sinus

There will be signs of sepsis;fever,chills,malaise and an elevated leukocyte count.

Pain may be referred to the premolars and molar teeth on the affected side and these teeth may also be sensitive to percussion

Chronic sinusitis This is a sequel of the former two,which has failed to resolve by 3

months.

There are no external signs, except in case of an acute exaceberation when increased pain and discomfort is apparent.

This type is usually associated with anatomical derangements that inhibit the outflow of mucous,like;deviation of the nasal septam and presence of concha bullosa.

It is also associated with allergic rhinitis,asthma,cystic fibrosis and dental infection.

Radiographic features

Radiodensity: radiographically,the thickening of the mucous membrane and the accumulation of secreations that accompany sinusitis reduce the air content and it will appear as radiopaque.

Allergic sinusitis: in the case of allergy,mucosa will be more lobulated in contrast to that in infection where it is straighter and parallel to the sinus wall.

Chronic sinusitis: chronic sinusitis may result in persistent opacification of the sinus and sclerosis or thickening of surrounding bone.

Antral halo appearance: sometimes if infected teeth are involved then inflammatory changes may lead to resorption of the antral floor and remodelling to produce the appearance described as an antral halo.

Resolution of sinusitis: resolution of acute sinusitis will appear as small clear areas appear in the interior of the sinus as the thickened mucosa gradually shrinks.

Diagnosis

Transillumination test: affected sinus will be found opaque. Radiograph: water’s view and OPG can be taken

Waters view showing maxillary sinus

Laboratory diagnosis: there is elevated leukocyte count.lining of maxillary sinus may show a typical acute inflammatory infiltrate with edema of the connective tissue and often hemorrhege. In chronic cases,cellular proliferation is present.

CT.scan:

Management

Acute sinusitis Anti-histamines for allergy Pseudoephedrine 30-60 mg Phenylephrine 2-4 times/day Amoxicillin 500 mg tid for 10-14 days

Topical nasal spray (unlimited daily use) Ipatropium

Chorinic sinusitis Nasal steroid spray Guafenesin

Decongestants Steam inhalation Nasal irrigation Antibiotics with exacerbations

Complication

Acute sinusitis Maxillary: usually uncomplicated Ethmoid: cavernous sinus thrombosis-serious Frontal: osteomyelitis of frontal bone; cavernous sinus thrombosis;

epidural, subdural, or intracerebral abscess; orbital extension Sphenoid: Rare; extension to internal carotid artery, cavernous sinuses,

pituitary, optic nerves.

Mucositis (Thickened mucous membrane)

The normal mucosal lining of the para nasal sinus is composed of respiratory epithelium and is approximately 1mm thick, and is not visualized on the radiograph. When the mucosa becomes inflamed from either an infectious or allergic process, it may increase in thickness 10mto 15 times and is then seen on the radiograph. This thickening is called mucositis. Any thickening greater than 3mm is most likely to pathological.

Clinical features

It is usually asymptomatic and is discovered on a routine radiograph.


It is seen as a non-corticated band noticeably more radiopaque than the air filled sinus, paralleling the bony wall of sinus.

Mucosal thickening seen distinctly on denta scan images.

Perforation of the floor of the maxillary sinus

Management

Removal of the cause.

Antral polyp

The thickened mucosa of chronically inflamed sinus frequently form irregular folds called as ‘polyps’.polypoid atrophy of mucosa may develop into an isolated area or number of ares throughout the sinus. Antrochoanal polyps, are solitary polyps arising from the maxillary antrum. They were first described by Killian in 1906. Although their etiology remains unknown, allergy has been implicated.

Clinical features

Age: it usually occurs in young persons.

Site: maxillary sinus is more involved as compared to other sinus.in maxillary sinus they may arise from any part of the sinus wall and occasionally pass through the ostium to appear in the nose as antrochoanal polyps.

Picture showing antral polyp

Symptoms: patients present with nasal obstruction,pain is very mild on pressure as mass present inside the nose.

Saints triad: it is associated with “saints triad”, ie.nasal and antral polyposis, aspirin sensitivity and asthma.

Exacerbation of asthma: polyps may exaceberate the asthma by causing obstruction of the nose. It is the most commonly pedunculated, or sessile mass which grows slowly.after the polyps grows to occupy most of the antrum it frequently hernites into the nasal cavity. this may be brought about by repeated sneezing or nose blowing in about 4-6% cases.

Radiological features

Appearance: it appear as homogenous soft mass with smooth,outwardly convex borders.single or multiple lesions may be present.if polyp occurs in the roof of the maxillary sinus in a patient with a history of trauma,the plain film examination may simulate a blow out fracture.

Destruction of walls of sinus: polyps may cause destruction or displacement of bone. They can displace or destroy medial or lateral wall.

CT features: have mucoid attenuation with mucosal enhancement seen at polyps surface. It appears as smooth homogenous mass.

MRI features: mucosa adjacent to polyps will enhance as compared to polyps

CT scan showing maxillary sinus

Management

Non surgical Oral and topical nasal steroid Corticosteroids

Surgical polypectomy Endoscopic sinus surgery

Osteomyelitis

Osteomyelitis (osteo- derived from the Greek word osteon, meaning bone, myelo- meaning marrow, and -itis meaning inflammation) simply means an infection of the bone or bone marrow. It can be usefully subclassified on the basis of the causative organism (pyogenic bacteria or mycobacteria), the route, duration and anatomic location of the infection.

Types

Infantile osteomyelitis Tuberculous osteomyelitis

Infentile osteomyelitis

It is a rare type of osteomyelitis seen in infants in few weeks after birth.it usually involves maxilla.

Clinical features

Site: it is more common in maxilla due to hematogenous route. Symptoms: fever, anorexia, dehydration in some cases, convulsants, and

vomiting may occur. Signs: redness and edema of eyelids, alveolar bone and palate of the

effected side.


Radiodensity: about 10 days after acute infection, the density of trabeculae will be decreased, with blurred and fuzzy.

Trabecular pattern: the earliest radiographic change is that trabeculae in involved area are thin,of poor density and slightly unsharp or blurred.the trabeculae soon loose their continuity as well as the little density present.individual trabeculae become fuzzy and indistinct.

Multiple radiolucency: subsequently, multiple radiolucencies appear which become apparent on radiograph.

Lamina dura: there is loss of continuity of lamina dura,which is seen in more than one tooth.

Diagnosis

Clinical diagnosis: fever, pain with maxillary involvement in the infant will give clue to the diagnosis

Management

Bacterial sampling and culture Vigorous (empirical) antibiotic treatment Drainage Give specific antibiotics based on culture and sensitivities Give analgesics Debridement Remove source of infection, if possible

Tuberculous osteomyelitis

Bone and joint tuberculosis is always hematogenous in origin. Primary focus is related to lung when disease is acquired by inhalation of human strain or to gastrointestinal tract if it is acquired by ingestion of bovine tubercle. The disease starts within the synovial membrane or in intra articular bone.the disease may develop in synovial joint especially the knee and hip joint. Tuberculosis osteomyelitis of maxilla or mandible or TMJ are rare entities

Cyst involving maxillary sinus

Mucous retention cyst (mucocele)

A mucocele is an expanding,destructive lesion that results from a blocked sinus ostium. The blockage may result from intra-antral or intra nasal inflammation,polyp or neoplasm.the entire sinus thus becomes the pathologic cavity. As mucous secritions accumulate and the sinus cavity fills, the increase in intra-antral pressure results in thinning,displacement,and in some cases destruction of sinus walls. When the cavity is filled with pus,it is termed an empyema,pyocele or mucopyocele.

Clinical features

90% of mucoceles occur in the ethmoidal and the frontal sinus and are rare in the maxillary sphenoidal sinus

In the maxillary sinus it may exert pressurenon the superior alveolar nerves causing radiating pain, with a swelling and fullness of the cheek.the swelling may first observed over the anterioinferior aspect of the antrum where the wall may be thinned or destroyed.

If the lesion expands inferiorly,it may cause loosening of the posterior teeth.

If the medial wall of the sinus is expanded the lateral wall of the nasal cavity will deform and the nasal airway may be observed.

If it expands into the orbit,it cause diplopia or proptosis.


The normal shape of the maxillary sinus is changed into a more circular shape as the mucocele enlarges.

The scalloped border of the frontal sinus is usually smoothed by expansion, and the intersinus septum may be displaced.

In the ethmoidal air cells, displacement of the lamina papyracea may occur, displacing the contents of the orbit.

In the sphenoid sinus the expansion may be in the superioe direction, suggesting a pituitary neoplasm.

The sinus cavities appear uniformly radiopaque.

Differential diagnosis

Cyst Benign tumor Malignancy Any suggestion of a lesion associated with occluded ostium should be a

mucocele. A large odontogenic cyst displacing the maxillary antral floor may mimic a mucocele.

Treatment

Surgical removal.

Complications

There are usually no complications.

Surgical ciliated cyst

It is a delayed complication arising years after surgery involving maxilla.

Clinical features

It is usually occurs in the 4th and 5th decades of life Mostly seen in males

The patient may complain of pain,discomfort or swelling of face or intra oral swelling of the palate or alveolus, with pus discharge


it is seen as a well defined radiolucency closely related to maxillary sinus. There is sclerosis of the surrounding bone. As the cyst enlarges it produces pressure effects, with thinning of the

sinus walls which may eventually perforate There may be resorption of mallxillary alveolar process. There is no communication between the cyst and maxillary sinus which

may be demonstated by injecting the sinus with radiopaque material.

Treatment

Enucleation

Pseudo cyst

Pseudocysts are like cysts, but lack epithelial or endothelial cells.

Initial management consists of general supportive care. Symptoms and complications caused by pseudocysts require surgery. Computed tomography (CT) scans are used for initial imaging of cysts, and endoscopic ultrasounds are used in differentiating between cysts and pseudocysts. Endoscopic drainage is a popular and effective method of treating pseudocysts.

This has not to be confused with the so-called 'pseudocystic appearance', mainly radiographically, of other lesions, such as Stafne static bone cyst and aneurysmal bone cyst of the jaws.

Symptoms

Pseudocysts are often asymptomatic. Symptoms are more common in larger pseudocysts, though the size and time present usually are poor indicators of potential complications.

Clinical features

it is mainly seen in 2nd and 3rd decades of life. Males are most commonly effected than female. Mostly involved sites are the antral floor and lateral wall of maxillary

sinus. There may be localized dull pain in the antral region or fullness and

numbness of cheek. There may be pain in the teeth and over the face over or near the sinus. Sometimes antral swelling may also occur.


it is homogenous mass that is more radiopaque than the surrounding sinus cavity.

It appears as a soft tissue mass rather than a calcified area so that medial and lateral landmarks can generally be visualized through the lesion.

It is found projecting from the floor of the sinus, although some may form on the lateral walls.

The cyst appers as spherical ,ovoid,or dome shaped It has a uniform and a smooth outline. They may have narrow or broad base They vary in size from minute to very large. There is no resorption of adjacent bone. Mucous type will associated with thickened mucosa while serous type is

appears normal.

Dome shaped radiolucency seen in left maxillary sinusSuggestive of antral pseudocyst

Treatment.

.Surgical drainage. Endoscopic drainage laproscopy

Radicular cyst

A radicular cyst is a cyst that most likely results when rests of epithelial cells (Malassez) in the periodontal ligament are stimulated to proliferate and undergo cystic degeneration by inflammatory products from a non-vital tooth.

Clinical features

Most common type of cyst of the jaws. Rarely seen before the age of 10. Most frequent between 20 and 60 years. More common in males than females 3 to 2. Maxilla affected more than 3 times the mandible. Cause slowly progressive painless swelling. No symptoms until they become large enough or infected.

If infection enters, the swelling becomes painful and may rapidly expand, partly due to inflammatory edema.

The swelling is rounded and at the first hard Later, when the bone has been reduced to egg-shell thickness, a crackling

sensation (crepitant) may be felt on pressure Finally, part of the wall is resorbed entirely away, leaving soft fluctuant

(rubbery and fluctuant) swelling, bluish in color, beneath the mucous membrane.

The dead tooth from which the cyst has originated is present, and its relationship to the cyst will be apparent in a radiograph

Pathogenesis

The main factors in the pathogenesis of cyst formation are:

Proliferation of epithelial lining and fibrous capsule Hydrostatic pressure of cyst fluid Resorption of Surrounding bone Infection from the pulp chamber induces inflammation and proliferation

of the epithelial rest of Malassez. If infection can be eliminated from the root canal, small radicular cysts

(up to 1 or 2 cm diameter) may regress without surgery. Radicular cyst expand in balloon-like fashion, wherever the local

anatomy permits, indicates that internal pressure is a factor in their growth.

The hydrostatic pressure within cysts is about 70 cm of water and therefore higher than the capillary blood pressure.

Cystic fluid is largely inflammatory exudate and contains high concentration of proteins, some of high molecular weight which can exert osmotic pressure.

Pathogenesis of radicular cyst

Consistent with the inflammation usually present in cyst walls, cyst fluid may contain cholesterol, breakdown products of blood cells, exfoliated epithelial cells, and fibrin.

Collagenases are present in the walls of keratocysts, but their contribution to cyst growth is also unclear.

All stages can be seen from a periapical granuloma containing a few strands of proliferation epithelium derived from the epithelial rest of Malassez, to an enlarging cyst with a hyperplastic epithelial lining and dense inflammatory infiltrate.

Epithelial proliferation results from irritant products leaking from an infected root canal to cause periapical inflammation.

The epithelial lining consists of stratified squamous epithelium of variable thickness.

It lack a well-defined basal cell layer and is sometimes incomplete. Hyaline bodies may be seen in the epithelium and mucous cells are often

present as a result of metaplasia. Long-standing cysts typically have a thin flattened epithelial lining, a

thick fibrous wall and minimal inflammatory infiltrate


In most cases the epicenter of a radicular cyst is located approximately at the apex of a nonvital tooth

Occasionally it appears on the mesial or distal surface of a tooth root, at the opening of an accessory canal or infrequently in a deep periodontal pocket

RADICALAR CYST INVOLVING THE MAXILLA

Most radicular cysts (60%) are found in the Maxilla, especially around incisors and canines.

Because of the distal inclination of the root, cysts that arise from the maxillary lateral incisor may invaginate the antrum.

Radicular cysts may also form in relation to a nonvital deciduous molar and be positioned buccal to the developing bicuspid.

CT scan showing maxillary sinus

Diagnosis

Is based on the combination of:

Adequate History Clinical Examination Selected Investigation:

Pulp vitality testing of associated teethRadiographs (intra/extra oral)Aspiration and analysis of cyst fluidsHistopathology

Management

Treatment of a tooth with a radicular cyst may include:

Extraction, Endodontic therapy, Apical surgery (Enucleation/Marsupilisation)

Neoplasm

Adenoameloblastoma (AOT)

Adenoameloblastoma is a lesion that is often found in the upper jaw. Some consider it a non-cancerous tumor, others a hamartoma (tumor-like growth) or cyst. Often, an early sign of the lesion is painless swelling. These tumors are rarely found outside of the jaw.

It is mostly seen in the maxilla

Symptoms:

Some of the symptoms of Adenoameloblastoma incude:

Jaw cyst Jaw tumor Sinus cyst Sinus tumor Dental cyst

Etiology

It is fairly uncommon, but It is seen more in young people. Two thirds of the cases are found in females

Presentation and diagnosis

Two thirds of cases are located in the anterior maxilla, and one third are present in the anterior mandible.

Two thirds of the cases are associated with an impacted tooth (usually being the canine).

On radiographs, the adenomatoid odontogenic tumor presents as a radiolucency (dark area) around an unerupted tooth extending past the cementoenamel junction.

It should be differentially diagnosed from a dentigerous cyst and the main difference is that the radiolucency in case of AOT extends apically beyond the cementoenamel junction.

Radiographs will exhibit faint flecks of radiopacities surrounded by a radiolucent zone.

It is sometimes misdiagnosed as a cyst.

Clinical features

Clinical features generally focus on complaints regarding a missing tooth. The lesion usually present as asymptomatic swelling which is slowly growing and often associated with an unerupted tooth. However, the rare peripheral variant occurs primarily in the gingival tissue of tooth-bearing areas. Unerupted permanent canine are the theeth most often involved in adenoameloblastoma.


The radiographic findings of AOT frequently resemble other odontogenic lesions such as dentigerous cysts, calcifying odontogenic cysts, calcifying odontogenic tumors, globule-maxillary cysts, ameloblastomas, odontogenic keratocysts and periapical disease . Whereas the follicular variant shows a well-circumscribed unilocular radiolucency associated with the crown and often part of the root of an unerupted tooth, the radiolucency of the extrafollicular type is located between, above or superimposed upon the roots of erupted permanent teeth. Displacement of neighbouring teeth due to tumor expansion is much more common than root resorptions. The peripheral lesions may show some erosions of the adjacent cortical bone. Comparing diagnostic arruracy between intraoral

periapical and panoramic radiographs Dare et al. found that intraoral periapical radiographs allow perception of the radiopacities in AOT as discrete foci having a flocculent pattern within radiolucency even with minimal calcifies deposits while panoramic often do not. Those calcified deposits are seen in approximately 78% of AOT . In addition, in one recently reported case MRI was useful to distinguish AOT from other lesions, even if it is difficult on periapical ordinal radiographies

IOPA showing canine in maxillary sinus

Treatment

Conservative surgical enucleation is the treatment modality of choice. For periodontal intrabony defects caused by AOT guided tissue regeneration with membrane technique is suggested after complete removal of the tumor. Recurrence of AOT is exceptionally rare. Only three cases in Japanese patients are reported in which the recurrence of this tumor occurred. Therefore, the prognosis is excellent.

Exostosis

An exostosis (plural: exostoses) is the formation of new bone on the surface of a bone. Exostoses can cause chronic pain ranging from mild to debilitatingly severe, depending on the shape, size, and location of the lesion.

If an exostosis is thought to be present your podiatrist will most likely have an x-ray taken of your foot to evaluate it. The underlying cause of forming the exostosis needs to be addressed. An exostosis can be treated conservatively or

surgically depending on location and symptoms. If a surgery is performed where the exostosis is removed this is termed an exostectomy.

Clinical features

The clinical features of osteochondromata are:

swelling - usually, at the metaphysis of a long bone lesions may be single or multiple rarely painful the lump is bony hard, although sometimes covered by a bursa which

may be tender

Radiographic features:

Radiologically, the osteochondroma is well-defined. Often the lesion may look smaller than it feels because the cartilage cap is invisible.

There are two main varieties that are seen:

conical cauliflower shaped

There may be partial calcification of the osteochondroma.

Pathology:

On cut surface the torus and exostosis show dense bone with a lamellar or laminated pattern. They are usually comprised of dense, mature, lamellar bone with scattered osteocytes and small marrow spaces filled with fatty marrow or a loose fibrovascular stroma. Some lesions have a thin rim of cortical bone overlying inactive cancellous bone with considerable fatty or hematopoietic marrow present. Minimal osteoblastic activity is usually seen, but occasional lesions will show abundant periosteal activity. Large areas of bone may show enlarged lacunae with missing or pyknotic osteocytes, indicative of ischemic damage to the bone.

Treatment & Prognosis:

Surgical excision

Enostosis

A hyperplasia of bone within the jaws. Also referred to as a dense bony island.

Clinical features

The lesions were all at least 1.5 cm. in diameter. Pain, drainage, or localized expansion of the jaw was present Womens are mostely effected

Causes

genetics stress infection metabolism,.

Symptoms:

The humerus is most commonly affected. Males are more commonly affected than females. The dog normally limps on the affected limb and only rarely holds the limb to prevent any weight from being placed on it.

Pathology

Enostoses are likely congenital or developmental, and are thought to represent either hamartomatous lesions or failure of osteoclastic activity during bone remodelling

Radiographic Features

Location: Anywhere throughout the maxilla and mandible. Edge: Well-defined to Well-localized, continuous with the surrounding

bone trabeculae. Shape: Does not always have a given shape, but may appear round, ovoid

or irregular in shape. Internal: Radiopaque, radiopacity of cancellous bone. Other: None. Number: May be single or multiple. If there are multiple sites throughout

the maxilla and/or mandible, an underlying systemic condition such as Gardner’s Syndrome should be considered.

Diagnosis

Diagnosis is made by pain on palpation of the long bones of the limbs. X-rays may show an increased density in the medullary cavity of the affected bones, often near the nutrient foramen (where the blood vessels enter the bone). This evidence may not be present for up to ten days after lameness begins.


In the vast majority of cases, bone islands have a pathognomonic appearance. Larger lesions may sometimes pose a diagnostic dillema, particularly in the setting of known malignancy.

Differential considerations include: osteoblastic metastasis osteoma osteoid osteoma low grade osteosarcoma

Squamous cell carcinoma

This originates from metaplastic epithelium of the sinus mucosal lining

Clinical features

The males are commonly effected. The most common symptom is facial pain or swelling, nasal obstruction

and lesion in the oral cavity. Lymphnodes are involved in most of the case. Erosion of the medial wall causes nasal obstruction, nasal discharge,

bleeding and pain. Expansion of the alveolar process in the maxillary sinus Sinus root and floor of the orbit causes symptoms related to eye diplopia

and proptosis, pain and hyperesthesia or anesthesia and pain over the cheek and upper teeth.


The medial wall of the sinus is best seen on the waters projections

Waters view showing maxillary sinus

As the lesion enlarges it may destroy the sinus walls and in general cause irregular radiolucent areas in the surrounding bone

Adjacent alveolar process may show bone destruction around the teeth or irregular widening of periodontal ligame t space.

The medial wall of the sinus maynbe thinned or destroyed and it may also extend into the nasal cavity.

Destruction of the floor and anterior and posterior walls may be dectected.


Sinusitis odontogenic cyst Large retention cyst

Treatment

Debridement of sinus Antifungal

– Amphotericin b– Rifampin

Syndromes associated with maxillary sinus

Crouzon’s syndrome

Crouzon syndrome is a genetic disorder known as a branchial arch syndrome. Specifically, this syndrome affects the first branchial (or pharyngeal) arch, which is the precursor of the maxilla and mandible. Since the branchial arches are important developmental features in a growing embryo, disturbances in their development create lasting and widespread effects.

Causes

Associations with mutations in the genes of FGFR2 and FGFR3 have been identified.

Heredity

Crouzon syndrome is autosomal dominant; children of a patient have a 50% chance of being affected

Symptoms

As a result of the changes to the developing embryo, the symptoms are very pronounced features, especially in the face. Low-set ears are a typical characteristic, as in all of the disorders which are called branchial arch syndromes. The reason for this abnormality is that ears on a fetus are much lower than those on an adult. During normal development, the ears "travel" upward on the head; however, in Crouzon patients, this pattern of development is disrupted. Ear canal malformations are extremely common, generally resulting in some hearing loss. In particularly severe cases, Ménière's disease may occur.

Diagnosis

Diagnosis of Crouzon syndrome usually can occur at birth by assessing the signs and symptoms of the baby. Further analysis, including radiographs, magnetic resonance imaging (MRI) scans, genetic testing, X-rays and CT scans can be used to confirm the diagnosis of Crouzon syndrome.

Treatment

Surgery

Dental significance

For dentists, this disorder is important to understand since many of the physical abnormalities are present in the head, and particularly the oral cavity. Common features are a narrow/high-arched palate, posterior bilateral crossbite, hypodontia (missing some teeth), and crowding of teeth. Due to maxillary hypoplasia, Crouzon patients generally have a considerable permanent underbite and subsequently cannot chew using their incisors. For this reason, Crouzon patients sometimes eat in an unusual way--eating fried chicken with a fork, for example, or breaking off pieces of a sandwich rather than taking a bite into it.

Binder syndrome (maxilla nasal dysplasia)

Binder's Syndrome/Binder Syndrome (Maxillo-Nasal Dysplasia) is a developmental disorder primarily affecting the anterior part of the maxilla and nasal complex (nose and jaw). It is a rare disorder and the causes are unclear. Hereditary and vitamin D deficiency during embryonic growth have been researched as possible causes.

clinical Characteristics

arhinoid face, intermaxillary hypoplasia, abnormal position of nasal bones, atrophy of nasal mucosa, reduced absent anterior nasal spine, absence of frontal sinus (not obligatory).

Synonyms:

Maxillo-nasal dysplasia. Maxillo-nasal dysostosis. Naso-maxillo-vertebral syndrome (Binder syndrome).

Prognosis:

The prognosis is good if there is no other problem associated.

Management:

Orthodontic therapy osteotomy when the children were older

.

Anthroliths.

An antrolith is a calcified mass within the maxillary sinus. The origin of the nidus of calcification may be extrinsic (foreign body in sinus) or intrinsic (stagnant mucus, fungal ball).

Most antroliths are small and asympotomatic. Larger ones may present as sinusitis with symptoms like pain and discharge.


Location: Maxillary sinuses. Edge: Well-defined, smooth or irregular outline. Shape: Round, ovoid. Internal: Radiopaque, may have a ‘laminated’ appearance with

radiopaque and radiolucent bands evident due to continued laying down of calcium salts. (This looks similar to layers of an onion.)

Number: May be single of multiple.

IOPA SHOWING AN IMAPACTED TEETH

IN THE MAXILLARY REGION

They appearas solitary or multiple, faintly to extremely radio-opaque masses embedded within the mucoperiosteum. The sinus wall is intact.

Treatment

surgical removel endoscopic sinus surgery


Aspergillosis infection

Traumatic injuries of maxillary sinuses

Tooth roots may be fractured as a result of various forms, including iatrogenic reasons. fractured roots may be forced into the sinus during extraction or subsequent attemps to retrieve them.

Excess root canal filling material may be forced through the apex of an upper posterior tooth during endodontic therapy. Foreign materials may be pushed into the antrum via an existing oro antral fistula. Metallic objects such as pellets, bullets and fragments of shells or bombs may be found if patients has been exposed to the same.

Clinical features

no visible signs and symptoms if the roots is displaced recently. Ask the patient to hold the nose while attempting to breathe out through,

similar to a valsalva maneuver, it will cause bubbles to appear within the blood contained within the fresh extraction.

If the patient has the root or tooth in the sinus for a number of days, he may present with sinusitis

The associated roots are usually of molars and premolars as the sinus is in close proximity to these teeth.


The dislodged fragments are usually found near the floor of the sinus because of the gravity. Sometimes the displaced structure may be mucosal, between the osseous wall of the sinus and the periosteum. The floor of the sinus and periosteum.

The foor of the sinus may break due to the displacement of the tooth fragment into the sinus.

THERE IS A ROOT FRAGMENT LOCATED OBLIQUELY AND APICAL TO THE APEX LINE

CT finding which showed that the tooth was located close to mesial wall of the sinus and roots


Exostoses of the sinus wall or the floor and the septa within the sinus, may mimic dental root fragments or even whole teeth.

Anthroliths

Treatment

Surgical removal

Sinus contusion

This occurs due to a blow to the face that damages the lining of the paranasal sinuses without fracturing the facial bone. There may be green stick fracture of the sinus with a resultant tearing injury to the mucosal lining.

Clinical features

There is a bloody nasal discharge, extreme tenderness of the involved sinus on pressure.

There is rapid resolution of the soft tissue changes.


Haziness of the sinus due to edema. An opaque sinus or fluid level resulting from hemorrhage from the

mucosal tear.


Sinusitis

Blow-out fracture

This results from sudden increase in the intraorbital pressure, due to may be a direct blow to the eye.

Clinical features

The pressure of the blow forces the inferior orbital content through the fracture.

It results in diplopia when the victim look upward and enophthalmus following reduction of edema and fat atropy.


Opacification of the sinus with or without a fluid level. There will be shadow of soft tissue mass in the upper portion of the sinus

and shadows of the depressed bone fragments into the sinus. A tear drop shaped radiopacity is produced in the upper part of the sinus,

due to the herniation of the orbital content downward into the sinus following the collapse of the antral roof.

The depression fracture of the orbit may be accompanied by the fracture of the antrum wall of the maxillary sinus.

CORONAL SECTION TOMOGRAPH OF PATIENT WITH BLOW OUT FRACTURE OF RIGHT ORBITAL FLOOR

Isolated fracture

This involves a single wall which may appear as a bright line on the radiograph.

The most common sites are the anterolateral wall of the antrum and the floor of the antrum, during extraction of the upper posterior teeth whose roots are in close proximity to the antrall floor.

Zygomatic complex fracture

This fractures occurs at the line of weakness and passes through the orbital floor, usually medial to the zygomaticomaxillary suture.

Clinical features

The fractured zygoma is forced into sinus. There may be tearing of the lining membrane with subsequent bleeding

into antrum.


the antrum appers cloudy or will show a fluid level.

Standard occipitomental showing fracture of the right zygomatic complex with a break of antral roof

Oroantral fistula

This is a pathological pathway connecting the oral cavity and the maxillary sinus. It may be caused due to extraction of teeth having chronic periapical infection, extraction of solitary tooth. Extraction of teeth having apices very close to the antral floor, blind instrumentation, surgical removal of large lesions in the upper jaws, malignant tumors,osteomyelitis, syphilis, malignant granulomatous lesion, facial trauma and inadequate blood clot formation.

Clinical features

immediate history of recent traumatic extraction or disappearance of the roots during extraction.

Passage of fluid into the nose from the oral cavity Inability to blow the cheek or smoke. Unilateral epitaxis, due to blood in the antrum escaping through the nasal

ostium. Alteration in vocal resonance.


There will be a break in the continuity of the floor of the maxillary sinus, which may be seen as a disalignment of a small portion of cortical layer of bone

Radiographic features of acute or chronic sinusitis are present.

Periapical showing a discontinuity of the antral foor

There may be evidence of the displaced root or tooth,and a second view of the sinus with the head in a different position may be required to asceration the the exact location of the displace object,

Treatment

It consist of repair and surgical closure under antibiotic therapy.

Reference

Dental and maxillofacial radiology: freny r kajodkar ,2nd edition, jaypee 2009 ; page 751 to 773

Text book of oral medicine: anil govidharao editors, ghom,2nd edition, jaypee 2010 , page 677 to696

Text book of oral and maxillo facial surgery: chitra chakravarthy editor,2nd edition, paras publishers 2011 ,page 246 to 263

Oral & Maxillofacial Pathology: Neville, B, et al. editors,3rd Ed. Saunders 2002 ,page 219 to 226

Text book of medicine; pramod john r editor,2nd edition,jaypee 2005,page 284 to 288

Education

Differiential diagnosis of maxillary sinus pathology