A large proliferative growth on the left side	A single non-healing ulcer on left lateral border of tongue

Leukoplakia [20] – A white plaque of questionable risk having excluded (other) known diseases or disorders that carry no increased risk for cancer. It has two main clinical types namely homogeneous and non-homogeneous leukoplakia.

Homogeneous lesions are uniformly white and flat with shallow surface cracks.

Non-homogeneous varieties include: speckled – mixed, white (predominant) and red; nodular – small polypoid outgrowths, rounded red or white excrescences; verrucous – wrinkled or corrugated surface appearance; and proliferative verrucous leukoplakia – multiple, simultaneous lesions.

Speckled non-homogeneous leukoplakia	Nodular non-homogeneous leukoplakia

Verrucous leukoplakia Courtesy: WHO IARC Screening group	Proliferative verrucous leukoplakia Courtesy: WHO IARC Screening group

Erythroplakia [20] – A fiery red patch that cannot be characterized clinically or pathologically as any other definable disease.¹⁰

Oral Submucous Fibrosis (OSMF) [21] – The clinical signs and symptoms depend on the stage of the condition.

Stage 1 involves stomatitis with erythematous mucosa, vesicles, ulcers, melanotic pigmentation and petechiae.

Erythematous mucosa, petechiae, ulcers Courtesy: WHO IARC Screening group	Melanotic pigmentation Courtesy: WHO IARC Screening group

Stage 2 includes fibrosis which is the hallmark of the disease. Early lesions show blanching of the oral mucosa with development of vertical palpable fibrous bands in the buccal mucosa and circular bands around the oral commissure later. These features result in a mottled marble like appearance of the mucosa. Other features include trismus, reduced mobility and size of the tongue, blanching floor of the mouth and palate, fibrotic and depigmented gingiva, shrunken or everted uvula, sunken cheeks and so on.

Blanching in right cheek Courtesy: WHO IARC Screening group	Blanching in lower lip Courtesy: WHO IARC Screening group

Reduced mouth opening Courtesy: WHO IARC Screening group	Blanching in plate & shrunken uvula Courtesy: WHO IARC Screening group

Stage 3 may present with additional lesions like leukoplakia, or speech and hearing deficit because of involvement of the tongue and the eustachian tube.

Oral Lichen Planus (OLP) [22] – OLP may present with both red and white elements the most common being the reticular type i.e. fine white lines or striae, in a network or annular pattern, called Wickham’s striae.

Papular Courtesy: Burket’s Oral Medicine, 11thed	Plaque type Courtesy: WHO IARC Screening Group

Other clinical varieties are papular (small white dots), plaque-like (homogeneous well-demarcated white plaque), bullous, erythematous/atrophic (homogeneous erythematous area), and ulcerative (fibrin-coated ulcers surrounded by an erythematous zone). The erythematous and ulcerative types are usually symptomatic. However, the reticular striae must be present alongwith these types to establish a clinical diagnosis of OLP.

Oral lichenoid lesion (OLL) [23] – OLLs share the clinical features of OLP, however, the former are usually unilateral and have a topographical association with the causative agent.

Smoker’s palate [22]– One of the most common oral mucosal clinical effects of smoking are white leathery lesions of the palate (smoker’s palate). An initial erythema is followed by greyish white palatal mucosa, alongwith multiple red dots representing orifices of the minor salivary glands.