PIGMENTED LESIONS OF THE ORAL MUCOSABlue, brown and black discoloration constitute the pigmentedlesions of the oral mucosa, these lesions represent a variety ofclinical entities, ranging from:-1-physiological changes (e.g. racial pigmentation ).2-manifestations of systemic illnesses (e.g. Addisons disease).3-Malignant neoplasm (e.g. melanoma and Kaposi sarcoma)4-Exogenous pigmentation is commonly due to foreign-bodyimplantation in the oral mucosa.5-Endogenous pigments include melanin, hemoglobin,hemosiderin and carotene.
Differential Diagnosis of Oral Pigmented LesionEvaluation of the patient presenting with pigmented lesion shouldinclude:-1-full medical and dental history, the history should include the onsetand duration of the lesion, the presence of associated skinhyperpigmentation the presence of systemic signs and symptoms ( e.gmalaise, fatigue, weight loss) and smoking habits.2-Extra oral and intra oral examinations. pigmented lesions on theface, perioral skin and lip should be noted. the number, distribution,size, shape and colour of intraoral pigmented lesions should beassessed.3-Investigations such as discopy test, radiography, biopsy andlaboratory investigations such as blood test can be used to confirm aclinical impression and reach a definitive diagnosis.
Pigmented lesions are classified into:-▼ BLUE/PURPLE VASCULAR LESIONS.HemangiomaVascular lesions presenting as proliferations of vascular channels aretumorlike hamartomasthe lesion may harbor vessels close to the overlying epithelium andappear reddish blue or, if a little deeper in the connective tissue, a deepblue. Angiomatous lesions occurring within muscle (so-calledintramuscular hemangiomas) may fail to show any surface discoloration.Clinicaly: Whereas most hemangiomasare raised and nodular, some may beﬂat, macular, and diffuse, particularly onthe facial skin, where they are referredto as port-wine stains
TREATMENT:-Since most hemangiomas spontaneously involute during teenage years Patientwho require treatment can undergo conventional surgery, laser surgery, orcryosurgery. Larger lesions that extend into muscles are more difficult toeradicate surgically, and scleroting agents such as 1% tetradecyl sulfate may betreated by intralesional injection
Varix*pathologic dilatations of veins or venules are varices or varicosities,*the chief site of such involvement in the oral tissues is the ventral tongue*Clinicaly:Lingual varicosities appear as tortuous serpentineblue, red, and purple elevations that course over the ventrolateralsurface of the tongue, with extension anteriorly.*They are painless and are not subject to rupture and hemorrhage*some can be blanched, others are not, due to the formation of intravascularthrombi.
The varix resembles the hemangioma both clinically and histologically, yet it isdistinguished by two features: (1) the patient’s age at its onset and(2) its etiology.
Hereditary Hemorrhagic TelangiectasiaCharacterized by multiple round or oval purple papules measuring less than 0.5cm in diameter, hereditary hemorrhagic telangiectasia (HHT) is a geneticallytransmitted disease, inherited as an autosomal dominant traitThere may be more than100 such purple papules on the vermilion and mucosalsurfaces of the lips as well as on the tongue and buccal mucosa. the facial skinand neck are also involved. Examination of the nasal mucosa will reveal similarlesions, and a past history of epistaxis may be a complaint. Indeed, deaths havebeen reported in HHT attributable to epistaxisDifferential diagnosis should includepetechial hemorrhages with an attendingplatelet disorder, petechiae are macularrather than papular and (as foci oferythrocyte extravasation with breakdownto hemosiderin) red or brown rather thanpurple
Microscopically:- HHT shows numerous dilated vascular channels withsome degree of erythrocyte extravasation around the dilated vessels.There is no treatment for the disease. If the patient would like to have thetelangiectatic areas removed for cosmetic reasons, the papules can be cauterizedby electrocautery in a staged series of procedures using local anesthesia
▼ BROWN MELANOTIC LESIONSEphelis and Oral Melanotic MaculeThe common cutaneous freckle, or ephelis represents an increase in melanin pigmentsynthesis by basal-layer melanocytesEphelides can be encountered on the vermilion border of the lips, with the lowerlip being the favored site since it tends to receive more solar exposure than theupper lip. The lesion is macular and ranges from being quite small to over acentimeter in diameter. Some patients report a prior episode of trauma to the area.The intraoral counterpart to the ephelis isthe oral melanotic macule. These lesionsare oval or irregular in outline, are brown oreven black, and tend to occur on the gingiva, palate, and buccal mucosa.
Microscopically,a normal epithelial layer isseen, and the basal cells contain numerousmelanin pigment granules without proliferation ofmelanocytesThe oral melanotic macule does not represent a melanocyticproliferation, and does not predispose to melanoma. Once it isremoved, no further surgery is required.
Malignant MelanomaOral mucosal melanomas are extremely rare. Their prevalence appears tobe higher among Japanese people than among other populations.Melanomas arising in the oral mucosa tend to occur on the anterior labialgingiva and the anterior aspect of the hard palate.clinically oral melanomas are macular brown and black plaques with anirregular outline. They may be focal or diffuse and mosaicEventually, melanomas become more diffuse, nodular with foci of hyperand hypopigmentation.
Teratment:- Excision with wide margins is the treatment of choice this may be difficult to accomplished because of the anatomical constrains and proximity to the viralstructures. radiation and chemotherapy are ineffective which adds to the difficulty associated with the management of this malignancy, the prognosis for patients with oral melanoma is much worse than that for patients with cutaneous lesions and the overall 5-years survival rate is 15%.
Physiologic (racial ) Pigmentation Black people, Asians, and dark-skinned Caucasians frequently show diffuse melanosis of the facial gingiva. In addition, the lingual gingiva and tongue mayexhibit multiple, diffuse, and reticulated brown macules. Although other causes of hyperpigmentation are possible, racial pigmentation, representing basilar melanosis, evolves in childhood and usually does not arise de novo in the adult. Therefore, any multifocal or diffuse pigmentation of recent onset should be investigated further to rule out endocrinopathic disease
Peutz-Jeghers SyndromeIn Peutz-Jeghers syndrome oral pigmentation is distinctive and is usuallypathognomonic. Multiple focal melanotic brown macules are concentrated about thelips while the remaining facial skin is less strikingly involved. The macules appearas freckles or ephelides usually measuring < 0.5 cm in diameter. Similar lesionsmay occur on the anterior tongue, buccal mucosa, and mucosal surface of the lips.Ephelides are also seen on the ﬁngers and handsHistologically, these lesions show basilar melanogenesis without melanocyticproliferation.
▼ BROWN HEME-ASSOCIATED LESIONS Ecchymosis Traumatic ecchymosis is common on the lips and face yet is uncommon in the oral mucosa. Immediately following the traumatic event, erythrocyte extravasation into the submucosa will appear as a bright red macule or as a swelling if a hematoma forms. The lesion will assume a brown coloration within a few days, after the hemoglobin is degraded to hemosiderin.*Certainly, patients taking anticoagulantdrugs may present with oralecchymosis, particularly on the cheek ortongue, either of which can be traumatizedwhile chewing. Coagulopathic ecchymosisof the skin and oral mucosa may also beencountered in hereditary coagulopathicdisorders and in chronic liver failure
PetechiaCapillary hemorrhages will appear red initially and turn brown in a few days oncethe extravasated red cells have lysed and have been degraded to hemosiderin.Petechiae secondary to plateletdeﬁciencies or aggregation disordersare usually not limited to the oralmucosa but occur concomitantly onskinoral petechiae are usually conﬁned to the soft palate, where 10 to 30 petechiallesions may be seen and can be attributed to suction. Excessive suction of the softpalate against the posterior tongue is self inﬂicted by many patients who have apruritic palate at the onset of a viral or an allergic pharyngitis; they simply “click”their palate. When traumatic or suction petechiae are suspected, the patientshould be instructed to cease whatever activity may be contributing to thepresence of the lesions. By 2 weeks, the lesions should have disappeared. Failureto do so should arouse suspicion of a hemorrhagic diathesis, and a platelet countand platelet aggregation studies must be ordered.
▼ GRAY/BLACK PIGMENTATIONSAmalgam TattooBy far, the most common source of solitary or focal pigmentation in theoral mucosa is the amalgam tattoo.*No signs of inflammation are present at the periphery ofthe lesion. In some cases especially when the amalgamparticles are large enough they can be seen in intraoralradiographs as fine radiopaque granules.
Hairy TongueHairy tongue is a relatively common condition of unknown etiology. The lesioninvolves the dorsum, particularly the middle and posterior one-third. Rarely arechildren affected. The papillae are elongated, sometimes markedly so, and have theappearance of hairs.Microscopically, the ﬁliform papillaeare extremely elongated andhyperplastic with keratosis. Externalcolonization of the papillae bybasophilic microbial colonies is aprominent featureTreatment consists of having the patient brush the tongue and avoid tea andcoffee for a few weeks. Since the cause is undetermined, the condition can recur.