Diagnosis of oral white lesions could be quite challenging. These lesions represent a good spectrum of lesions with different etiology and various prognoses. The diagnosis of white lesions varies from benign reactive lesions to more serious dysplastic and carcinomatous lesions. While there are some classic features that help distinguish these lesions, similar features may produce to some complications in diagnosis. Efforts should be made to determine a particular diagnosis to stop time elapse in treatment of patients with more serious lesions. a choice tree may be a flowchart that organizes features of lesions so as to assist clinicians to succeed in a logical conclusion. To use the choice tree, one should begin from the left side of the tree, makes the primary decision, and proceeds to the far right of the tree where the definite diagnoses are listed Oral lesions are often classified into four groups comprising of ulcerations, pigmentations, exophytic lesions, and red-white lesions [2]. Although white lesions constitute only 5% of oral pathoses, a number of these lesions like leukoplakia, lichen ruber planus , and proliferative verrucous leukoplakia have malignant potential as high as 0.5–100% [3]. Therefore, white lesions mandate an appropriate clinical diagnostic approach to exclude the likelihood of malignancy. The onset of oral white lesions are often acquired or congenital, with a history of long-lasting existence within the latter form. Oral white lesions are often caused by a thickened keratotic layer or an accumulation of non-keratotic material. Accordingly, when a clinician confronts a white area on the oral mucosa, the primary issue to be elucidated is whether or not it are often scraped off by means of a bit of gauze or not. If so, a superficial non-keratotic layer like pseudomembranes, most ordinarily caused by fungal infections or caustic chemicals, should be suspected. Otherwise, white lesions are often attributed to increased thickness of keratin layer, which could are induced by local frictional irritation, immunologic reactions, or more crucial processes like premalignant or malignant transformation.In the next step, any specific clinical pattern of white lesions like papular, annular, reticular or erosive-ulcerative patterns, or a mixture of them (characteristic for lichenoid lesions) should be inspected so as to differentiate white patterned lesions from non-patterned ones.Therefore, this narrative review paper focuses on three clinical steps to approach oral white lesions: the primary step is to work out whether the lesion is congenital or acquired; the second and third steps are to examine if it are often wiped off or not and if it's a special pattern or not
