Benign odontogenic tumors of the jaws.
I – Introduction:
* Maxillary tumor pathology is as vast as it is frequent. It covers pathologies developed from the maxillomandibular regions.
* Benign maxillary tumors include a variety of histological entities. In the majority of cases, these tumors are related to elements of the dental system and are called odontogenic tumors . More rarely, they are bone tumors strictly speaking, then called non-odontogenic tumors .
2. Definitions:
- Benign maxillary tumors are localized proliferative neoformations of odontogenic or non-odontogenic origin, but which develop in an anarchic manner, at the expense of the mandible or maxilla and have a slow evolution, without distant metastases.
- Odontogenic tumors are tumors where dental tissue and the tooth play a direct role in their development.
- Non-odontogenic tumors are tumors that develop independently of dental tissue, but yet, in close proximity to the teeth, where the role of the teeth in their genesis is indirect.
- Hamartoma (dysembryoplasia) : is a tissue malformation with a tumoral appearance, composed of an abnormal mixture of constituent elements normally present in the organ in which they develop. The function of which may be altered (example: odontoma).
- Locally aggressive tumor: Benign histological character contrasting with infiltration of neighboring tissues but never giving metastases, purely local development and a tendency to recur due to the difficulties of excision;
- Potentially malignant tumor: Benign tumor likely to become cancerous.
Nomenclature :
- The nomenclature of tumors follows a precise terminology. A tumor name generally consists of a root and a suffix, and may be associated with an adjective.
- The root : defines differentiation (adeno designates a glandular tumor, amelo designates a tumor derived from adamantine tissue; …).
- The suffix:
- oma is used to name benign tumors. However, there are exceptions (e.g. lymphomas and melanomas are malignant tumors);
- matosis refers to the presence of multiple or diffuse tumors (angiomatosis, adenomatosis);
- blastoma refers to an embryonic tumor (ameloblastoma)
3.Reminder of odontogenesis:
The embryological development of the tooth bud results from interactions between the dental lamina and the ectomesenchyme.
Enamel is born under the induction of the ectomesenchyme of the dental lamina comprising 4 layers of cells:
- an external dental epithelium with cubic cells
- a stellate reticulum
- an intermedium stratum
- an internal base of preameloblasts
The peripheral reflection zones of these layers represent the future Hertwig sheath.
- Preameloblasts induce in the mesenchymal papilla the differentiation of fibroblasts into odontoblasts which will form dentin, moreover the Hertwig ridges induce the construction of root dentin.
- The secretion of dentin in turn induces the maturation of preameloblasts into ameloblasts responsible for the secretion of enamel and the appearance of cementoblasts forming cementum.
- The mesenchymal papilla becomes the dental pulp lined with functional odontoblasts.
- At the end of the development of the dental bud:
– the odontogenic epithelium has secreted the enamel
– the ectomesenchyme ensures the formation of the dental pulp; dentine (odontoblasts), root cementum (cementoblast). - Odontogenic tumors (OT) derive from the epithelium, ectomesenchyme and/or mesenchyme of the developing dental organ: thus, they result from dysfunction of the development of the tooth and its adjacent structures.
- Also each step of cellular interaction and each step of dental growth are likely to generate a type of odontogenic tumor.
- We therefore distinguish:
1-benign epithelial odontogenic tumors,
2- Benign epithelial-connective odontogenic tumors;
3- Benign mesenchymal odontogenic tumors
4- classifications:
These tumors have been subject to several classifications, changes in nomenclature systems and nosological difficulties, and this is due to:
- Their histology, which is not homogeneous from the point of view of
- Distribution of tissue found in the lesion. Also, some formations are not tumors strictly speaking but “hamartomas” as is the case with odontomas which cannot be excluded
- Their odontogenic origin or not.
- Absence of anatomo-pathological parallelism: the classification of pathologists does not correspond to individualized clinical entities
1- Common clinical and radiological signs:
1.1 Clinical signs:
- Benign odontogenic tumors are pathological entities specific to the maxilla, however their symptomatology is not specific. It is also common with non-odontogenic tumors and maxillary cysts.
- Bone swelling constitutes the main clinical feature: hard swelling, integral with the bone, of hard or depressible consistency.
- Dental signs may be present: dental mobility, displacements, abnormal developments, delayed healing, etc.
1.2. Radiological signs:
- The opaque radio aspect indicates the osteo, cemento or odonto-formative character.
- Clear radiographic appearance: osteolytic or cystic character.
- The mixed aspect: odontogenic nature +++
- The outline of the image can be: clear, cloudy or irregular, underlined or not with a thick or thin line (osteocondensation border).
- Mono or polygeodic.
- The X-ray also makes it possible to specify the relationships between the tumor and neighboring structures (sinus, dental canal, etc.).
- NB: We are talking about a
- Geode (very clear, regular contours, surrounded by a fine whitish border of osteocondisation)
- Gap (reduction in density giving a more or less well-defined image, of light tone, outline not marked by a dense line).
I. Epithelial odontogenic tumors
1- Ameloblastomas
It is the second most common odontogenic tumor after odontoma.
- First described in literature in 1868
- Consists of a proliferation of odontogenic epithelium within a fibrous stroma. It is called “non-inductive” because it does not produce any calcified element such as enamel, dentin or other.
a/ Pathophysiology
- Most ameloblastomas arise from the odontogenic epithelium: remains of the dental lamina or Could also arise from the epithelial cells of odontogenic cysts (follicular cysts+++) and odontomas
Clinical forms
* In the new 4th edition , 4 types have been identified: * Conventional ameloblastoma
*Peripheral
*Unicystic
*Metastasizing.
A/ Ameloblastoma (conventional)
Definition: Ameloblastoma is a benign but locally aggressive epithelial tumor by:
- Its local evolutionary and invasive potential.
- Its high potential for recurrence (if incomplete excision)
- Risk of malignant degeneration estimated at 5%.
Epidemiology :
Age : 4th and 5th decades
Sex : no sexual predilection
Location: the mandibular molar region +++, extension towards the angle and the mandibular ramus (90% of cases).
In 2nd position the anterior mandibular region, followed by the posterior maxillary region then the anterior maxillary region
Clinical
- Slow, painless expansion (discovered incidentally during a routine dental exam)
- These tumors can progress, leading to significant bone invasion, tooth displacement or loss, lysis of bone cortices, and invasion of soft tissue.
- The weakened bone can then fracture.
- Paresthesias of the inferior dental nerve have been reported, but remain an extremely rare sign in the evolution of these tumors.
- At the maxilla level, the extension can then be made towards the orbital cavity, the base of the skull or the sphenoidal structures on the sella turcica.
1. Epithelial odontogenic tumors
b/ Radiology
- The polygeodic image is the most evocative:
- the rounded or oval geodes, of unequal size, with a clear and homogeneous background, regularly bordered by a fine peripheral border, lean against each other and overlap, creating a classic “soap bubble” image; the cortices are progressively thinned, or even blown away in places by this multilocular bone destruction;
- more frequently, the image is vast, with a polycyclic outline, finely partitioned by vestiges of the bony partitions between the multicentric geodes;
- Later, the ameloblastoma takes on the appearance of a large single geode, with a scalloped outline, pushing back the sigmoid notch, but classically preserves the condyle.
- Dental rhizalysis can be found in teeth adjacent to the osteolytic process or in intralesional dental inclusions.
Macroscopy : the appearance varies from solid to cystic or both
Histology
- The follicular subtype:
The most common, consisting of lobules of epithelial cells embedded in a vascularized connective stroma.
- The plexiform subtype
Composed of a network of epithelial cords anastomosing with each other in a network. Each cord has a base of cubic or columnar cells of the pre-ameloblastic type with an internal zone containing very few stellate cells.
- The acanthomatous subtype
Shows varying degrees of epithelial metaplasia. Keratin pearls may be noted alongside the stellate elements.
- The granular subtype
The least frequent, composed of epithelial cells with eosinophilic granular cytoplasm. These granules correspond to a lysosomal proliferation.
B/ Unicystic ameloblastoma
- Is a variant of intraosseous ameloblastoma, consisting of a single large cyst. It is usually diagnosed after histopathological examination, because it clinically and radiologically resembles an odontogenic cyst.
Epidemiology: constitutes 5% to 20% of ameloblastomas.
Age : 2nd and 3rd decades
Gender : slight male predominance
Localization most commonly located in the area of the mandibular third molar, extending towards the angle, and the ascending ramus, followed by the body and symphysis in second position. Most maxillary cases occur in the posterior areas
Clinical:
It is less aggressive, less blowing
Radiologically: variable appearance:
A- Polygeodic image:
It is the most evocative.
* Rounded or oval geodes, uneven, with a light and homogeneous background, bordered by a fine peripheral edge. By superimposing, these geodes create the classic “soap bubble” image, the cortices are progressively thinned or even blown in places.*
* Sometimes the image is vast, with a polycyclic outline, finely partitioned.
B – Monogeodic image:
A large single geode, with a scalloped outline, blowing and thinning the cortex at the mandibular level, pushing back the sigmoid notch but preserving the condyle.
Sometimes repression or inclusion of dental organs.
CT scan allows to specify the tissue nature (guide the diagnosis); the relationship with the lower dental canal; the sinuses; …*
Macroscopy : presents as a monocystic lesion, sometimes with thickenings that may fill the entire lumen.
Histology:
Unicystic ameloblastoma describes three histological variants
- Luminal type: It develops only in the epithelium of the cyst wall
- Intraluminal type: These are projections of the ameloblastic epithelium towards the light giving a plexiform appearance
- Mural type: It involves punctate infiltrations of the tumor wall with a plexiform or follicular appearance.
Differential diagnosis:
- Multiloculated type : keratocysts, myxomas, ameloblastic fibroma, central giant cell granuloma, solitary cysts.
- Uniloculated type : dentigerous cyst, keratocyst, periapical cyst.
Evolution :
– In the absence of treatment, ameloblastoma progresses slowly in bursts.
– Ameloblastoma is endowed with a particular aggressiveness justifying the extension and the recurrence.
Treatment :
– Bone excision and curettage in monogeodic forms;
– Partial or interruptive mandibular resection as first intention in polygeodic forms.
2- Epidermoid odontogenic tumor
* Epidermoid odontogenic tumor was first described by Pullon in 1975.
- Also called benign epithelial odontogenic tumor, squamous odontogenic tumor. It is exceptional.
Epidemiology :
– Age: of onset: between the 2nd and 7th decade , with a peak around the 3rd decade
– Sex: No sex predilection.
– Location: In the maxilla: incisor-canine region +++
In the mandible premolar-molar region +++
* Multiple localizations in both jaws have already been observed in the same patient. A peripheral localization has also been observed
Clinical
Often asymptomatic
Sometimes: dental mobility with pain and inflammatory signs.
With spontaneous or axial percussion sensitivity
From localized tooth loss, in the absence of localized or generalized periodontal disease.
Radiology
- Unilocular radiolucent image, having a semicircular appearance sometimes approaching a triangular shape, bordered by a rim of condensation from an alveolar segment, directly above or surrounding the repressed dental roots. Rare are advanced cases of TOE described as multilocular radiolucency.
When large volume: rhizalysis possible. Transition to the multilocular form rare but possible. Certain lesions can affect several quadrants and can affect several members of the same family.
Macroscopy
The tumor mass can be:
- Be solid, homogeneous, crumbly and blackish.
- Either excavated (hollow).
- Cleaving healthy bone is sometimes easy, sometimes difficult.
Histology
- It presents islands of well-differentiated mature epidermoid cells in a fibrous stroma, resting on a basal layer of flattened cells, and not cylindrical as in keratoameloblastomas. The epithelial islands present micro-foci of cystic degeneration.
Possible areas of keratinization. Presence of microcalcifications
Differential diagnosis
- Radiologically
– Periodontal disease: when the limits are difficult to individualize
- lateral periodontal cyst
- dentigerous cyst
- keratocyst
- Central odontogenic fibroma
- Histologically
The differential diagnosis is with ameloblastoma.
dystrophic and acanthomatous
Treatment
Excision with or without extraction of the tooth.
3- Adenomatoid odontogenic tumor
- It is a rare, non-aggressive tumor, with progressive growth and little recurrence, representing <5% of odontogenic tumors.
- Arises from the odontogenic epithelium of the enamel organ, or from a follicular cyst, it includes pseudo-canal structures.
Epidemiology : It is encountered more frequently in Africa (Nigeria in particular).
– Age : especially young subjects in the second decade
– Gender : the female gender is most affected.
– Location : canine region of the maxilla.
The mandible is affected twice less (symphyseal and parasymphyseal).
- Sometimes described as “2/3 tumor” (Marx and Stern, 2003):
- 2/3 of cases in young people,
- 2/3 of cases in the maxilla,
- 2/3 of cases associated with an included tooth,
- 2/3 of cases the included tooth is the canine.
Clinic: Painless swelling, slowly increasing in size Sometimes delayed eruption or tooth displacement
Radiology:
- Well-defined monogeodic image, with a diameter of 2 to 4 cm.
– More advanced tumors may contain discrete or marked radiopaque foci, constituting a useful diagnostic criterion (punctuated character of the image by fine opacities)
3 topographical variants
1 -FOLLICULAR TOA (PERICORONAL
2 – Extra-follicular (extra-coronal) TOA
3 – TOA peripheral
Macroscopy: the tumor has a consistency that can be relatively firm or clearly cystic. The section slice is gray-white, dotted with cystic cavities filled with a yellowish liquid.
Histologically:
- The tumor is formed by epithelial cells arranged in nodules, spirals and rosettes.
- Within its nodules are duct-like spaces characteristic of adenomatoid odontogenic tumor.
- Areas of calcification are present in places. They represent attempts at enamel formation.
Differential diagnosis:
- Follicular form: the dentigerous cyst
- Extrafollicular form: residual cyst, globulomaxillary cyst, lateral periodontal cyst, periapical lesion odontogenic keratocyst, ameloblastoma or central giant cell tumor,
- TOA, at a more advanced stage, presenting calcifications, resembles a calcified odontogenic cyst, calcified epithelial odontogenic tumor,
4- Calcified odontogenic epithelial tumor TEOC (Pindborg tumor):
Rare locally invasive tumor initially described by Pindborg in 1955 and 1958. Characterized by the intra-epithelial development of structures of probably amyloid nature, likely to calcify.
– Epidemiology :
-Slight predominance in men.
-Age: This is a tumor that affects patients aged 20 to 60 years, with two peaks of incidence, one at 30 years and the other later at 50 years
– Location :
- Intraosseous form : the most frequent: mandibular molar region 2/3 of cases
* An included tooth (DDS+++): approximately one in two cases.
- The extra-osseous form , rare: anterior maxillary region+++, at the level of the gum.
– Clinic: non-specific.
– Radiology:
– Initially a radiolucent unilocular image is observed
– The image becomes polygeodic in a “beehive” shape when the tumor is old. Giving rise to radiopaque spots which increase in size, number and density (characteristic calcifications) with irregular peripheral osteocondensation.
- In the maxilla, the tumor frequently progresses towards the sinus and nasal cavities causing: epistaxis, nasal deviation.
– Macroscopy : Grayish, pinkish or yellowish tumor, firm, sometimes with cystic spaces when cut.
– Friable consistency due to the presence of calcifications.
– When it is associated with a tooth, the latter is included in the mass by its crown.
– Histology : Tumor sometimes encapsulated in a fibrous capsule, the epithelial cells organized in layers dug with glandular cavities in a loose connective stroma, which may show signs of degeneration.
A homogeneous eosinophilic pseudoamyloid substance between the epithelial trabeculae calcifies, giving concentric rings (Liesgang rings).
– Differential diagnosis:
- Follicular cyst
- Keratocyst
- Calcified odontogenic cyst
- Myxoma
- Ameloblastoma
Treatment
Healing after complete excision.
Mixed odontogenic tumors (epithelial and mesenchymal)
1- Ameloblastic fibroma
- Proliferation of epithelial and mesenchymal tissue without formation of enamel or dentin; this tumor therefore does not contain hard, calcified tissue.
- Rare tumor, said to form from Hertwig’s sheath.
Epidemiology: constitutes 1.5-6.5% of all odontogenic tumors
- Age: occurs before 21 years of age (younger population than ameloblastoma).
– Sex: a slight male predilection.
- Preferred location: the posterior region of the mandible is the most affected (74%).
The maxilla is affected in 20% of cases (posterior region)
- Clinic: usually asymptomatic, incidental discovery.
-When the volume is significant: swelling with mobility and dental movements.
- Radiology:
The lesion initially lies on the occlusal surface of a tooth, near the alveolar crest, in a “hat” manner.
Small lesion: The image is monogeodic, with clear limits.
When the volume is important: multilobulated image blowing out the cortices.
One tooth included in 75% of cases (1M and 2M permanent molars).
– Macroscopy: Surgical exploration reveals a solid mass of grayish-white color, firm or slightly soft. May be encapsulated, with a smooth external surface, areas of hemorrhagic necrosis may be visible
– Histology: Epithelial structures reminiscent of the enamel organ and areas of connective tissue simulating the dental papilla.
Differential diagnosis:
- ameloblastoma,
- residual cyst,
- dentigerous cyst
- adenomatoid odontogenic tumor
- aneurysmal bone cyst
- central giant cell repair granuloma
- odontogenic myxoma
2-The primordial odontogenic tumor
Primordial odontogenic tumor is a newly defined entity in the 2017 WHO classification. It was first described in 2014. There are less than 10 cases published to date.
Epidemiology :
Age: The tumor often affects patients within the first 2 decades.
Gender: No gender predilection.
Location: The most commonly affected site is the molar region of the mandible.
Clinically: Most primary odontogenic tumors are asymptomatic, but they usually cause facial asymmetry)
Radiologically: a well-defined radiolucent image is usually observed associated with an impacted tooth (most commonly the mandibular 3M). This could cause displacement and root resorption of adjacent teeth.
Macroscopy: Overall, it is a well-circumscribed solid multi-lobulated mass without cystic change, associated with a tooth that can easily detach from the tumor.
Histopathology: Histopathologically, it is characterized by loose connective tissue, resembling dental papillae, of variable amount, surrounded by cuboidal/columnar epithelium resembling the inner enamel epithelium of the enamel organ.
The characteristic feature is the columnar or cuboidal epithelium covering the periphery of the tumor.
4-Odontomas
Odontomas are mixed epithelial and ectomesenchymal tumors composed of hard and soft dental tissues. They are usually considered a malformation (a hamartoma), rather than a neoplasm. There are two types of odontomas, compound and complex
- Epidemiology: Odontomas are the most common odontogenic tumors (representing 19% of odontogenic tumors).
- They usually occur in the first and second decades, with equal distribution between the sexes.
- Location :
– Anterior maxillary compound odontomas
-Complex odontomas of the posterior mandible.
Clinically:
- They are usually diagnosed incidentally during a routine X-ray examination.
- Faced with the absence of a permanent tooth on the arch with abnormal persistence of the temporary tooth
- Presence of an abnormal arch.
- Complex odontomas can cause expansion of the jaws while maintaining the cortical limit, as they can be complicated later by inflammatory reactions.
X-ray assessment :
- Compound odontomas : Radiologically, it shows a disharmonious opacity, of anterior location, constituted by the accumulation of multiple rudimentary dental bodies, the whole being surrounded by a clear halo with well-defined contours.
- Complex odontomas: The lesion produces an irregular opacity, of dental tone, posteriorly located, surrounded by a clear halo formed by the lesion tissue in the process of mineralization.
- Macroscopy : In complex odontomas, there is a single mass of randomly arranged soft and hard dental structures
- whereas in compound odontomas, hard and soft tissues form small tooth-like structures.
Differential diagnosis :
- Supernumerary tooth,
- Ameloblastic fibroma (during their development phase)
4-Odogenic phantom cell tumor
- It is a benign, locally invasive, mixed odontogenic tumor. It occurs mainly in intraosseous sites (aggressive), less frequently in the soft tissues of the gingiva and alveolar mucosa (less aggressive). It is the solid form of the ”Gorlin” cyst.
- Epidemiology :
- The reported age of tumor patients ranges from 11 to 79 years, with peak incidence between the 4th and 6th decades.
- Gender: The tumor is twice as common in men as in women.
- Location :
- The posterior regions of the maxilla and mandible, with a slight predilection for the mandible (affected in 53% of cases)
- the extra-osseous variant shows a predilection for the anterior part of the maxillae (gingiva and alveolar mucosa).
- Clinically: The tumor is usually asymptomatic, slow growing. In some cases, resorption of cortical bone with extension into soft tissues may be observed.
- The extraosseous variant presents as an exophytic nodule of the gingiva or sessile alveolar mucosa, sometimes pedunculated. Many occur in edentulous areas.
- Macroscopy: Tumors are solid and have macroscopic areas of calcification, microcystic areas may be present, but they do not constitute a significant area of the tumor.
- Histopathology: Intraosseous and extraosseous types show similar histopathology.
- The basic histopathologic feature is the presence of ameloblastoma-like islands. Minor cysts may form in the epithelial islands. A characteristic feature is the transformation of epithelial cells into ghost cells. Some ghost cells undergo calcification. Ghost cell dentinogenic tumors produce dysplastic dentin or osteodentin-like material. Ghost cells may be trapped in this dysplastic dentin, which in some areas may be mineralized.
- Differential diagnosis:
- This tumor can be distinguished from ameloblastoma by the presence of large numbers of ghost cells and dysplastic dentin.
- It can be difficult to distinguish from calcifying odontogenic cyst.
3- Mesenchymal odontogenic tumors
* Mesenchymal odontogenic tumors are divided into 3 entities, the histogenesis of which is still uncertain, but the benignity of which is recognized.
1- Odontogenic fibroma:
- Odontogenic fibroma is a rare benign tumor that accounts for 0.1% of all odontogenic tumors .
There is an extra-osseous peripheral form, and a central intra-osseous form.
Epidemiology
- Central odontogenic fibroma: has a wide age range and is relatively common in women.
- Peripheral fibroids: appear twice as often in women as in men and the peak incidence is between the 2nd and 4th decades.
Clinical
– Central odontogenic fibroma is often asymptomatic
Large tumors are associated with pain, bone expansion and tooth mobility.
– Peripheral odontogenic fibroma presents as a firm, sessile gingival mass covered by normal-appearing mucosa, resembling fibrous hyperplasia.
- Radio: Central expansive lesion beginning as a spherical radiolucent lesion with secondary appearance of radiopacities,
- Larger tumors may become multilocular displacing cortical bone during development without penetration or reactive periosteal bone formation.
Rhizalysis in 1/3 of cases. A radiolucent border separates the lesion from the adjacent bone. Possible associated impacted tooth .
Differential diagnosis
- Ameloblastoma
- Ameloblastic fibroma
- Neurofibroma
- fibrous lesions of the jaws
- desmoplastic fibroma.
- Follicular cyst and keratocyst: when an included tooth is associated with it
2- Myxoma: Odontogenic myxoma: Fibromyxoma:
- Odontogenic myxoma is a rare, benign, locally invasive neoplasm that does not metastasize. These tumors, whose pathogenesis is still controversial, represent 0.04 to 0.6% of oral cavity tumors and 3 to 7% of odontogenic tumors.
- It is the third most common odontogenic tumor after ameloblastoma and odontomas. Derived from the mesenchymal tissue of the tooth germ by myxoid transformation.
- The tumor is almost always intraosseous, but peripheral types have been described.
Epidemiology :
Age: It is usually diagnosed in the 2nd to 4th decades
- Pediatric cases, occurring at 13 and 17 months of age, respectively, have been reported
Gender: Twice as common in women as in men.
Location: the mandibular molar region and in the ramus > the maxilla
- Damage to soft tissues is exceptional (gum, alveolo-dental ligament)
PS: In the maxilla, the lesion develops in 74% of cases in the region anterior to the first molar and it is more aggressive in the maxilla, with intra-sinus development and therefore long-term asymptomatic development which often leads to late discoveries.
Clinically:
Unilateral bone swelling, painless, without functional disorders, which can reach impressive volumes. Palpation reveals a mass of firm consistency, which can be elastic (cortical breach). The associated dental signs are mobility, displacement or loss of teeth. In the maxilla, intra-sinus development allows for a long asymptomatic extension, which often results in late discovery.
- Radiology:
- Small lesions may have a unilocular radiolucent appearance.
- However, most lesions present polygeodic radiolucent images with polycyclic edges , poorly defined, its geometric compartmentalization is at sharp or right angles creating a “torn fisherman’s net” or “tennis racket” appearance. The condyle may be affected.
- Macroscopy: Characteristic: Shiny, smooth, whitish, grayish or yellowish tumor. It is often poorly limited and frequently spreads into the bone and adjacent soft tissues.
Its consistency varies greatly (depending on the abundance of collagen fibers): firm (fibromyxoma) or gelatinous (myxoma).
- Differential diagnosis :
– Ameloblastoma
– Bone sarcomas
– Chondroma
– Fibroid
– Giant cell tumors
– Intraosseous hemangioma
3- Benign cementoblastoma: true cementomas
- The only true cementum tumor, a rare neoplasm (1 to 6% of odontogenic tumors) characterized by the formation of proliferating cementum tissue in contact with a dental root, with authentic functional cementoblasts.
- Benign tumor with slow progression, non-recurrent after enucleation.
Epidemiology :
– Age : tumor is frequently observed during the second and third decades of life.
– Sex : No sex predilection.
– Location : 3/4 of cases in the mandible: M and PM+++ regions
In 50% of cases, it affects the first permanent molar.
Baby teeth are very rarely affected.
Clinic:
- Revealing curvature + moderate pain.
Possible aggressive behaviors include: bone expansion, cortical erosion, tooth displacement, envelopment of multiple adjacent teeth, involvement of the maxillary sinus, and infiltration of the root canal and pulp chamber.
The affected tooth(s) remain alive.
Macroscopy : Cementoblastoma typically presents as a calcified mass adhering to the root(s) of a tooth and surrounded by a non-calcified matrix of a brownish gray color.
Differential diagnosis:
- hypercementosis (apex visible)
- periapical or focal bone dysplasia
- chronic focal sclerosing osteomyelitis (visible apex),
- cemento-ossifying fibroma,
- condensing osteitis (decayed necrotic tooth),
- Osteoblastoma (not adhering to roots)
CONCLUSION
A good knowledge of these tumors allows their precise diagnosis. This can only be obtained after a good collection of clinical, radiological and especially histological data.
In all cases, if the anatomopathological diagnosis does not appear compatible with the evolution (benign odontogenic tumors of the jaws.
TO: 2023-2024.
I – Introduction:
* Maxillary tumor pathology is as vast as it is frequent. It covers pathologies developed from the maxillomandibular regions.
* Benign maxillary tumors include a variety of histological entities. In the majority of cases, these tumors are related to elements of the dental system and are called odontogenic tumors . More rarely, they are bone tumors strictly speaking, then called non-odontogenic tumors .
2. Definitions:
- Benign maxillary tumors are localized proliferative neoformations of odontogenic or non-odontogenic origin, but which develop in an anarchic manner, at the expense of the mandible or maxilla and have a slow evolution, without distant metastases.
- Odontogenic tumors are tumors where dental tissue and the tooth play a direct role in their development.
- Non-odontogenic tumors are tumors that develop independently of dental tissue, but yet, in close proximity to the teeth, where the role of the teeth in their genesis is indirect.
- Hamartoma (dysembryoplasia) : is a tissue malformation with a tumoral appearance, composed of an abnormal mixture of constituent elements normally present in the organ in which they develop. The function of which may be altered (example: odontoma).
- Locally aggressive tumor: Benign histological character contrasting with infiltration of neighboring tissues but never giving metastases, purely local development and a tendency to recur due to the difficulties of excision;
- Potentially malignant tumor: Benign tumor likely to become cancerous.
Nomenclature :
- The nomenclature of tumors follows a precise terminology. A tumor name generally consists of a root and a suffix, and may be associated with an adjective.
- The root : defines differentiation (adeno designates a glandular tumor, amelo designates a tumor derived from adamantine tissue; …).
- The suffix:
- oma is used to name benign tumors. However, there are exceptions (e.g. lymphomas and melanomas are malignant tumors);
- matosis refers to the presence of multiple or diffuse tumors (angiomatosis, adenomatosis);
- blastoma refers to an embryonic tumor (ameloblastoma)
3.Reminder of odontogenesis:
The embryological development of the tooth bud results from interactions between the dental lamina and the ectomesenchyme.
Enamel is born under the induction of the ectomesenchyme of the dental lamina comprising 4 layers of cells:
- an external dental epithelium with cubic cells
- a stellate reticulum
- an intermedium stratum
- an internal base of preameloblasts
The peripheral reflection zones of these layers represent the future Hertwig sheath.
- Preameloblasts induce in the mesenchymal papilla the differentiation of fibroblasts into odontoblasts which will form dentin, moreover the Hertwig ridges induce the construction of root dentin.
- The secretion of dentin in turn induces the maturation of preameloblasts into ameloblasts responsible for the secretion of enamel and the appearance of cementoblasts forming cementum.
- The mesenchymal papilla becomes the dental pulp lined with functional odontoblasts.
- At the end of the development of the dental bud:
– the odontogenic epithelium has secreted the enamel
– the ectomesenchyme ensures the formation of the dental pulp; dentine (odontoblasts), root cementum (cementoblast). - Odontogenic tumors (OT) derive from the epithelium, ectomesenchyme and/or mesenchyme of the developing dental organ: thus, they result from dysfunction of the development of the tooth and its adjacent structures.
- Also each step of cellular interaction and each step of dental growth are likely to generate a type of odontogenic tumor.
- We therefore distinguish:
1-benign epithelial odontogenic tumors,
2- Benign epithelial-connective odontogenic tumors;
3- Benign mesenchymal odontogenic tumors
4- classifications:
These tumors have been subject to several classifications, changes in nomenclature systems and nosological difficulties, and this is due to:
- Their histology, which is not homogeneous from the point of view of
- Distribution of tissue found in the lesion. Also, some formations are not tumors strictly speaking but “hamartomas” as is the case with odontomas which cannot be excluded
- Their odontogenic origin or not.
- Absence of anatomo-pathological parallelism: the classification of pathologists does not correspond to individualized clinical entities
1- Common clinical and radiological signs:
1.1 Clinical signs:
- Benign odontogenic tumors are pathological entities specific to the maxilla, however their symptomatology is not specific. It is also common with non-odontogenic tumors and maxillary cysts.
- Bone swelling constitutes the main clinical feature: hard swelling, integral with the bone, of hard or depressible consistency.
- Dental signs may be present: dental mobility, displacements, abnormal developments, delayed healing, etc.
1.2. Radiological signs:
- The opaque radio aspect indicates the osteo, cemento or odonto-formative character.
- Clear radiographic appearance: osteolytic or cystic character.
- The mixed aspect: odontogenic nature +++
- The outline of the image can be: clear, cloudy or irregular, underlined or not with a thick or thin line (osteocondensation border).
- Mono or polygeodic.
- The X-ray also makes it possible to specify the relationships between the tumor and neighboring structures (sinus, dental canal, etc.).
- NB: We are talking about a
- Geode (very clear, regular contours, surrounded by a fine whitish border of osteocondisation)
- Gap (reduction in density giving a more or less well-defined image, of light tone, outline not marked by a dense line).
I. Epithelial odontogenic tumors
1- Ameloblastomas
It is the second most common odontogenic tumor after odontoma.
- First described in literature in 1868
- Consists of a proliferation of odontogenic epithelium within a fibrous stroma. It is called “non-inductive” because it does not produce any calcified element such as enamel, dentin or other.
a/ Pathophysiology
- Most ameloblastomas arise from the odontogenic epithelium: remains of the dental lamina or Could also arise from the epithelial cells of odontogenic cysts (follicular cysts+++) and odontomas
Clinical forms
* In the new 4th edition , 4 types have been identified: * Conventional ameloblastoma
*Peripheral
*Unicystic
*Metastasizing.
A/ Ameloblastoma (conventional)
Definition: Ameloblastoma is a benign but locally aggressive epithelial tumor by:
- Its local evolutionary and invasive potential.
- Its high potential for recurrence (if incomplete excision)
- Risk of malignant degeneration estimated at 5%.
Epidemiology :
Age : 4th and 5th decades
Sex : no sexual predilection
Location: the mandibular molar region +++, extension towards the angle and the mandibular ramus (90% of cases).
In 2nd position the anterior mandibular region, followed by the posterior maxillary region then the anterior maxillary region
Clinical
- Slow, painless expansion (discovered incidentally during a routine dental exam)
- These tumors can progress, leading to significant bone invasion, tooth displacement or loss, lysis of bone cortices, and invasion of soft tissue.
- The weakened bone can then fracture.
- Paresthesias of the inferior dental nerve have been reported, but remain an extremely rare sign in the evolution of these tumors.
- At the maxilla level, the extension can then be made towards the orbital cavity, the base of the skull or the sphenoidal structures on the sella turcica.
1. Epithelial odontogenic tumors
b/ Radiology
- The polygeodic image is the most evocative:
- the rounded or oval geodes, of unequal size, with a clear and homogeneous background, regularly bordered by a fine peripheral border, lean against each other and overlap, creating a classic “soap bubble” image; the cortices are progressively thinned, or even blown away in places by this multilocular bone destruction;
- more frequently, the image is vast, with a polycyclic outline, finely partitioned by vestiges of the bony partitions between the multicentric geodes;
- Later, the ameloblastoma takes on the appearance of a large single geode, with a scalloped outline, pushing back the sigmoid notch, but classically preserves the condyle.
- Dental rhizalysis can be found in teeth adjacent to the osteolytic process or in intralesional dental inclusions.
Macroscopy : the appearance varies from solid to cystic or both
Histology
- The follicular subtype:
The most common, consisting of lobules of epithelial cells embedded in a vascularized connective stroma.
- The plexiform subtype
Composed of a network of epithelial cords anastomosing with each other in a network. Each cord has a base of cubic or columnar cells of the pre-ameloblastic type with an internal zone containing very few stellate cells.
- The acanthomatous subtype
Shows varying degrees of epithelial metaplasia. Keratin pearls may be noted alongside the stellate elements.
- The granular subtype
The least frequent, composed of epithelial cells with eosinophilic granular cytoplasm. These granules correspond to a lysosomal proliferation.
B/ Unicystic ameloblastoma
- Is a variant of intraosseous ameloblastoma, consisting of a single large cyst. It is usually diagnosed after histopathological examination, because it clinically and radiologically resembles an odontogenic cyst.
Epidemiology: constitutes 5% to 20% of ameloblastomas.
Age : 2nd and 3rd decades
Gender : slight male predominance
Localization most commonly located in the area of the mandibular third molar, extending towards the angle, and the ascending ramus, followed by the body and symphysis in second position. Most maxillary cases occur in the posterior areas
Clinical:
It is less aggressive, less blowing
Radiologically: variable appearance:
A- Polygeodic image:
It is the most evocative.
* Rounded or oval geodes, uneven, with a light and homogeneous background, bordered by a fine peripheral edge. By superimposing, these geodes create the classic “soap bubble” image, the cortices are progressively thinned or even blown in places.*
* Sometimes the image is vast, with a polycyclic outline, finely partitioned.
B – Monogeodic image:
A large single geode, with a scalloped outline, blowing and thinning the cortex at the mandibular level, pushing back the sigmoid notch but preserving the condyle.
Sometimes repression or inclusion of dental organs.
CT scan allows to specify the tissue nature (guide the diagnosis); the relationship with the lower dental canal; the sinuses; …*
Macroscopy : presents as a monocystic lesion, sometimes with thickenings that may fill the entire lumen.
Histology:
Unicystic ameloblastoma describes three histological variants
- Luminal type: It develops only in the epithelium of the cyst wall
- Intraluminal type: These are projections of the ameloblastic epithelium towards the light giving a plexiform appearance
- Mural type: It involves punctate infiltrations of the tumor wall with a plexiform or follicular appearance.
Differential diagnosis:
- Multiloculated type : keratocysts, myxomas, ameloblastic fibroma, central giant cell granuloma, solitary cysts.
- Uniloculated type : dentigerous cyst, keratocyst, periapical cyst.
Evolution :
– In the absence of treatment, ameloblastoma progresses slowly in bursts.
– Ameloblastoma is endowed with a particular aggressiveness justifying the extension and the recurrence.
Treatment :
– Bone excision and curettage in monogeodic forms;
– Partial or interruptive mandibular resection as first intention in polygeodic forms.
2- Epidermoid odontogenic tumor
* Epidermoid odontogenic tumor was first described by Pullon in 1975.
- Also called benign epithelial odontogenic tumor, squamous odontogenic tumor. It is exceptional.
Epidemiology :
– Age: of onset: between the 2nd and 7th decade , with a peak around the 3rd decade
– Sex: No sex predilection.
– Location: In the maxilla: incisor-canine region +++
In the mandible premolar-molar region +++
* Multiple localizations in both jaws have already been observed in the same patient. A peripheral localization has also been observed
Clinical
Often asymptomatic
Sometimes: dental mobility with pain and inflammatory signs.
With spontaneous or axial percussion sensitivity
From localized tooth loss, in the absence of localized or generalized periodontal disease.
Radiology
- Unilocular radiolucent image, having a semicircular appearance sometimes approaching a triangular shape, bordered by a rim of condensation from an alveolar segment, directly above or surrounding the repressed dental roots. Rare are advanced cases of TOE described as multilocular radiolucency.
When large volume: rhizalysis possible. Transition to the multilocular form rare but possible. Certain lesions can affect several quadrants and can affect several members of the same family.
Macroscopy
The tumor mass can be:
- Be solid, homogeneous, crumbly and blackish.
- Either excavated (hollow).
- Cleaving healthy bone is sometimes easy, sometimes difficult.
Histology
- It presents islands of well-differentiated mature epidermoid cells in a fibrous stroma, resting on a basal layer of flattened cells, and not cylindrical as in keratoameloblastomas. The epithelial islands present micro-foci of cystic degeneration.
Possible areas of keratinization. Presence of microcalcifications
Differential diagnosis
- Radiologically
– Periodontal disease: when the limits are difficult to individualize
- lateral periodontal cyst
- dentigerous cyst
- keratocyst
- Central odontogenic fibroma
- Histologically
The differential diagnosis is with ameloblastoma.
dystrophic and acanthomatous
Treatment
Excision with or without extraction of the tooth.
3- Adenomatoid odontogenic tumor
- It is a rare, non-aggressive tumor, with progressive growth and little recurrence, representing <5% of odontogenic tumors.
- Arises from the odontogenic epithelium of the enamel organ, or from a follicular cyst, it includes pseudo-canal structures.
Epidemiology : It is encountered more frequently in Africa (Nigeria in particular).
– Age : especially young subjects in the second decade
– Gender : the female gender is most affected.
– Location : canine region of the maxilla.
The mandible is affected twice less (symphyseal and parasymphyseal).
- Sometimes described as “2/3 tumor” (Marx and Stern, 2003):
- 2/3 of cases in young people,
- 2/3 of cases in the maxilla,
- 2/3 of cases associated with an included tooth,
- 2/3 of cases the included tooth is the canine.
Clinic: Painless swelling, slowly increasing in size Sometimes delayed eruption or tooth displacement
Radiology:
- Well-defined monogeodic image, with a diameter of 2 to 4 cm.
– More advanced tumors may contain discrete or marked radiopaque foci, constituting a useful diagnostic criterion (punctuated character of the image by fine opacities)
3 topographical variants
1 -FOLLICULAR TOA (PERICORONAL
2 – Extra-follicular (extra-coronal) TOA
3 – TOA peripheral
Macroscopy: the tumor has a consistency that can be relatively firm or clearly cystic. The section slice is gray-white, dotted with cystic cavities filled with a yellowish liquid.
Histologically:
- The tumor is formed by epithelial cells arranged in nodules, spirals and rosettes.
- Within its nodules are duct-like spaces characteristic of adenomatoid odontogenic tumor.
- Areas of calcification are present in places. They represent attempts at enamel formation.
Differential diagnosis:
- Follicular form: the dentigerous cyst
- Extrafollicular form: residual cyst, globulomaxillary cyst, lateral periodontal cyst, periapical lesion odontogenic keratocyst, ameloblastoma or central giant cell tumor,
- TOA, at a more advanced stage, presenting calcifications, resembles a calcified odontogenic cyst, calcified epithelial odontogenic tumor,
4- Calcified odontogenic epithelial tumor TEOC (Pindborg tumor):
Rare locally invasive tumor initially described by Pindborg in 1955 and 1958. Characterized by the intra-epithelial development of structures of probably amyloid nature, likely to calcify.
– Epidemiology :
-Slight predominance in men.
-Age: This is a tumor that affects patients aged 20 to 60 years, with two peaks of incidence, one at 30 years and the other later at 50 years
– Location :
- Intraosseous form : the most frequent: mandibular molar region 2/3 of cases
* An included tooth (DDS+++): approximately one in two cases.
- The extra-osseous form , rare: anterior maxillary region+++, at the level of the gum.
– Clinic: non-specific.
– Radiology:
– Initially a radiolucent unilocular image is observed
– The image becomes polygeodic in a “beehive” shape when the tumor is old. Giving rise to radiopaque spots which increase in size, number and density (characteristic calcifications) with irregular peripheral osteocondensation.
- In the maxilla, the tumor frequently progresses towards the sinus and nasal cavities causing: epistaxis, nasal deviation.
– Macroscopy : Grayish, pinkish or yellowish tumor, firm, sometimes with cystic spaces when cut.
– Friable consistency due to the presence of calcifications.
– When it is associated with a tooth, the latter is included in the mass by its crown.
– Histology : Tumor sometimes encapsulated in a fibrous capsule, the epithelial cells organized in layers dug with glandular cavities in a loose connective stroma, which may show signs of degeneration.
A homogeneous eosinophilic pseudoamyloid substance between the epithelial trabeculae calcifies, giving concentric rings (Liesgang rings).
– Differential diagnosis:
- Follicular cyst
- Keratocyst
- Calcified odontogenic cyst
- Myxoma
- Ameloblastoma
Treatment
Healing after complete excision.
Mixed odontogenic tumors (epithelial and mesenchymal)
1- Ameloblastic fibroma
- Proliferation of epithelial and mesenchymal tissue without formation of enamel or dentin; this tumor therefore does not contain hard, calcified tissue.
- Rare tumor, said to form from Hertwig’s sheath.
Epidemiology: constitutes 1.5-6.5% of all odontogenic tumors
- Age: occurs before 21 years of age (younger population than ameloblastoma).
– Sex: a slight male predilection.
- Preferred location: the posterior region of the mandible is the most affected (74%).
The maxilla is affected in 20% of cases (posterior region)
- Clinic: usually asymptomatic, incidental discovery.
-When the volume is significant: swelling with mobility and dental movements.
- Radiology:
The lesion initially lies on the occlusal surface of a tooth, near the alveolar crest, in a “hat” manner.
Small lesion: The image is monogeodic, with clear limits.
When the volume is important: multilobulated image blowing out the cortices.
One tooth included in 75% of cases (1M and 2M permanent molars).
– Macroscopy: Surgical exploration reveals a solid mass of grayish-white color, firm or slightly soft. May be encapsulated, with a smooth external surface, areas of hemorrhagic necrosis may be visible
– Histology: Epithelial structures reminiscent of the enamel organ and areas of connective tissue simulating the dental papilla.
Differential diagnosis:
- ameloblastoma,
- residual cyst,
- dentigerous cyst
- adenomatoid odontogenic tumor
- aneurysmal bone cyst
- central giant cell repair granuloma
- odontogenic myxoma
2-The primordial odontogenic tumor
Primordial odontogenic tumor is a newly defined entity in the 2017 WHO classification. It was first described in 2014. There are less than 10 cases published to date.
Epidemiology :
Age: The tumor often affects patients within the first 2 decades.
Gender: No gender predilection.
Location: The most commonly affected site is the molar region of the mandible.
Clinically: Most primary odontogenic tumors are asymptomatic, but they usually cause facial asymmetry)
Radiologically: a well-defined radiolucent image is usually observed associated with an impacted tooth (most commonly the mandibular 3M). This could cause displacement and root resorption of adjacent teeth.
Macroscopy: Overall, it is a well-circumscribed solid multi-lobulated mass without cystic change, associated with a tooth that can easily detach from the tumor.
Histopathology: Histopathologically, it is characterized by loose connective tissue, resembling dental papillae, of variable amount, surrounded by cuboidal/columnar epithelium resembling the inner enamel epithelium of the enamel organ.
The characteristic feature is the columnar or cuboidal epithelium covering the periphery of the tumor.
4-Odontomas
Odontomas are mixed epithelial and ectomesenchymal tumors composed of hard and soft dental tissues. They are usually considered a malformation (a hamartoma), rather than a neoplasm. There are two types of odontomas, compound and complex
- Epidemiology: Odontomas are the most common odontogenic tumors (representing 19% of odontogenic tumors).
- They usually occur in the first and second decades, with equal distribution between the sexes.
- Location :
– Anterior maxillary compound odontomas
-Complex odontomas of the posterior mandible.
Clinically:
- They are usually diagnosed incidentally during a routine X-ray examination.
- Faced with the absence of a permanent tooth on the arch with abnormal persistence of the temporary tooth
- Presence of an abnormal arch.
- Complex odontomas can cause expansion of the jaws while maintaining the cortical limit, as they can be complicated later by inflammatory reactions.
X-ray assessment :
- Compound odontomas : Radiologically, it shows a disharmonious opacity, of anterior location, constituted by the accumulation of multiple rudimentary dental bodies, the whole being surrounded by a clear halo with well-defined contours.
- Complex odontomas: The lesion produces an irregular opacity, of dental tone, posteriorly located, surrounded by a clear halo formed by the lesion tissue in the process of mineralization.
- Macroscopy : In complex odontomas, there is a single mass of randomly arranged soft and hard dental structures
- whereas in compound odontomas, hard and soft tissues form small tooth-like structures.
Differential diagnosis :
- Supernumerary tooth,
- Ameloblastic fibroma (during their development phase)
4-Odogenic phantom cell tumor
- It is a benign, locally invasive, mixed odontogenic tumor. It occurs mainly in intraosseous sites (aggressive), less frequently in the soft tissues of the gingiva and alveolar mucosa (less aggressive). It is the solid form of the ”Gorlin” cyst.
- Epidemiology :
- The reported age of tumor patients ranges from 11 to 79 years, with peak incidence between the 4th and 6th decades.
- Gender: The tumor is twice as common in men as in women.
- Location :
- The posterior regions of the maxilla and mandible, with a slight predilection for the mandible (affected in 53% of cases)
- the extra-osseous variant shows a predilection for the anterior part of the maxillae (gingiva and alveolar mucosa).
- Clinically: The tumor is usually asymptomatic, slow growing. In some cases, resorption of cortical bone with extension into soft tissues may be observed.
- The extraosseous variant presents as an exophytic nodule of the gingiva or sessile alveolar mucosa, sometimes pedunculated. Many occur in edentulous areas.
- Macroscopy: Tumors are solid and have macroscopic areas of calcification, microcystic areas may be present, but they do not constitute a significant area of the tumor.
- Histopathology: Intraosseous and extraosseous types show similar histopathology.
- The basic histopathologic feature is the presence of ameloblastoma-like islands. Minor cysts may form in the epithelial islands. A characteristic feature is the transformation of epithelial cells into ghost cells. Some ghost cells undergo calcification. Ghost cell dentinogenic tumors produce dysplastic dentin or osteodentin-like material. Ghost cells may be trapped in this dysplastic dentin, which in some areas may be mineralized.
- Differential diagnosis:
- This tumor can be distinguished from ameloblastoma by the presence of large numbers of ghost cells and dysplastic dentin.
- It can be difficult to distinguish from calcifying odontogenic cyst.
3- Mesenchymal odontogenic tumors
* Mesenchymal odontogenic tumors are divided into 3 entities, the histogenesis of which is still uncertain, but the benignity of which is recognized.
1- Odontogenic fibroma:
- Odontogenic fibroma is a rare benign tumor that accounts for 0.1% of all odontogenic tumors .
There is an extra-osseous peripheral form, and a central intra-osseous form.
Epidemiology
- Central odontogenic fibroma: has a wide age range and is relatively common in women.
- Peripheral fibroids: appear twice as often in women as in men and the peak incidence is between the 2nd and 4th decades.
Clinical
– Central odontogenic fibroma is often asymptomatic
Large tumors are associated with pain, bone expansion and tooth mobility.
– Peripheral odontogenic fibroma presents as a firm, sessile gingival mass covered by normal-appearing mucosa, resembling fibrous hyperplasia.
- Radio: Central expansive lesion beginning as a spherical radiolucent lesion with secondary appearance of radiopacities,
- Larger tumors may become multilocular displacing cortical bone during development without penetration or reactive periosteal bone formation.
Rhizalysis in 1/3 of cases. A radiolucent border separates the lesion from the adjacent bone. Possible associated impacted tooth .
Differential diagnosis
- Ameloblastoma
- Ameloblastic fibroma
- Neurofibroma
- fibrous lesions of the jaws
- desmoplastic fibroma.
- Follicular cyst and keratocyst: when an included tooth is associated with it
2- Myxoma: Odontogenic myxoma: Fibromyxoma:
- Odontogenic myxoma is a rare, benign, locally invasive neoplasm that does not metastasize. These tumors, whose pathogenesis is still controversial, represent 0.04 to 0.6% of oral cavity tumors and 3 to 7% of odontogenic tumors.
- It is the third most common odontogenic tumor after ameloblastoma and odontomas. Derived from the mesenchymal tissue of the tooth germ by myxoid transformation.
- The tumor is almost always intraosseous, but peripheral types have been described.
Epidemiology :
Age: It is usually diagnosed in the 2nd to 4th decades
- Pediatric cases, occurring at 13 and 17 months of age, respectively, have been reported
Gender: Twice as common in women as in men.
Location: the mandibular molar region and in the ramus > the maxilla
- Damage to soft tissues is exceptional (gum, alveolo-dental ligament)
PS: In the maxilla, the lesion develops in 74% of cases in the region anterior to the first molar and it is more aggressive in the maxilla, with intra-sinus development and therefore long-term asymptomatic development which often leads to late discoveries.
Clinically:
Unilateral bone swelling, painless, without functional disorders, which can reach impressive volumes. Palpation reveals a mass of firm consistency, which can be elastic (cortical breach). The associated dental signs are mobility, displacement or loss of teeth. In the maxilla, intra-sinus development allows for a long asymptomatic extension, which often results in late discovery.
- Radiology:
- Small lesions may have a unilocular radiolucent appearance.
- However, most lesions present polygeodic radiolucent images with polycyclic edges , poorly defined, its geometric compartmentalization is at sharp or right angles creating a “torn fisherman’s net” or “tennis racket” appearance. The condyle may be affected.
- Macroscopy: Characteristic: Shiny, smooth, whitish, grayish or yellowish tumor. It is often poorly limited and frequently spreads into the bone and adjacent soft tissues.
Its consistency varies greatly (depending on the abundance of collagen fibers): firm (fibromyxoma) or gelatinous (myxoma).
- Differential diagnosis :
– Ameloblastoma
– Bone sarcomas
– Chondroma
– Fibroid
– Giant cell tumors
– Intraosseous hemangioma
3- Benign cementoblastoma: true cementomas
- The only true cementum tumor, a rare neoplasm (1 to 6% of odontogenic tumors) characterized by the formation of proliferating cementum tissue in contact with a dental root, with authentic functional cementoblasts.
- Benign tumor with slow progression, non-recurrent after enucleation.
Epidemiology :
– Age : tumor is frequently observed during the second and third decades of life.
– Sex : No sex predilection.
– Location : 3/4 of cases in the mandible: M and PM+++ regions
In 50% of cases, it affects the first permanent molar.
Baby teeth are very rarely affected.
Clinic:
- Revealing curvature + moderate pain.
Possible aggressive behaviors include: bone expansion, cortical erosion, tooth displacement, envelopment of multiple adjacent teeth, involvement of the maxillary sinus, and infiltration of the root canal and pulp chamber.
The affected tooth(s) remain alive.
Macroscopy : Cementoblastoma typically presents as a calcified mass adhering to the root(s) of a tooth and surrounded by a non-calcified matrix of a brownish gray color.
Differential diagnosis:
- hypercementosis (apex visible)
- periapical or focal bone dysplasia
- chronic focal sclerosing osteomyelitis (visible apex),
- cemento-ossifying fibroma,
- condensing osteitis (decayed necrotic tooth),
- Osteoblastoma (not adhering to roots)
CONCLUSION
A good knowledge of these tumors allows their precise diagnosis. This can only be obtained after a good collection of clinical, radiological and especially histological data.
In all cases, if the anatomopathological diagnosis does not appear compatible with the evolution (recurrence), new biopsies must be carried out.
In the future, immunostaining techniques and imaging techniques may provide additional information to support diagnosis and prognosis.
), new biopsies must be performed.
In the future, immunostaining techniques and imaging techniques may provide additional information to support diagnosis and prognosis.
Benign odontogenic tumors of the jaws.
Cracked teeth can be healed with modern techniques.
Gum disease can be prevented with proper brushing.
Dental implants integrate with the bone for a long-lasting solution.
Yellowed teeth can be brightened with professional whitening.
Dental X-rays reveal problems that are invisible to the naked eye.
Sensitive teeth benefit from specific toothpastes.
A diet low in sugar protects against cavities.