| abrasion | the wearing away of a substance or structure through some unusual or abnormal mechanical process. |
| annular | shaped like a ring. |
| atrophy | loss of the normal thickness of the mucosa resulting in an increased translucency. |
| contusion (bruise) | a superficial injury, usually painful or tender, produced by impact without laceration. There may or may not be a color due to hemorrhage. |
| crust | dried residue of a combination of any or all of the following: serum, blood, cellular detritus, purulent discharge, or other exudates. Crust is seen on skin, including vermilion of lip. |
| ecchymosis | a nonelevated area of hemorrhage, larger than a petechia. |
| erosion | a depressed, superficial lesion that results from partial loss of the mucosa. The epithelium above the basal cell layer is denuded. An erosion often arises secondary to rupture of a vesicle or bulla; therefore, the base of a ruptured vesicle could represent an area of erosion. Erosions are moist and slightly depressed; healing rarely results in scarring. |
| eschar | a slough produced by burning or a corrosive application. |
| excoriation | a scratch that removes the cutaneous epidermis, producing a superficial lesion. |
| fissure | a narrow, linear cleavage or groove of the mucosa that may or may not extend through the mucosa. A fissure may be normal or abnormal; it typically affects the lips and paraoral tissues. When pathogenic organisms infect a fissure, pain, ulceration, and inflammation often result. |
| fistula | an abnormal passageway that leads from a suppurative cavity, cyst, or abscess to the surface of the mucosa (epithelium). An abscessed tooth often produces a clinically evident pustule at the terminal end of the fistula known as a parulis (gum boil). |
| keratosis | increased production and retention of keratin resulting in a raised lesion. |
| laceration | a wound made by tearing. As a consequence, it has irregular edges. |
| linear | arranged in a fashion to resemble a line. |
| papilla | a small nipple-shaped projection or elevation. |
| papillary | describing a tumor or growth exhibiting numerous surface projections. |
| papillomatous | similar to or resembling a papilloma; another term for papillary. |
| patch | a circumscribed area that is larger than a macule and differentiated from the surrounding epidermis by color or texture, or both. Like the macule the patch is neither elevated nor depressed. |
| pedunculated | describing a tumor or growth whose base is narrower than the widest part of the lesion. |
| petechia | a round, pinpoint area of hemorrhage. |
| plaque | a lesion that is slightly elevated and is flat on its surface. |
| polypoid | a lesion resembling a polyp. |
| pseudomembrane | a membranous layer of exudate containing organisms, precipitated fibrin, necrotic cells, and inflammatory cells that is produced by an inflammatory reaction on the surface of a tissue. |
| punctate | resembling or marked with points or dots. |
| scale | an increased rate of Malpighian cell proliferation of the epidermis results in nonretention of superficial cells; the desquamating layers are scales. |
| scar | the result of an injury that produces either an atrophy or a hypertrophy of the mucosa with an increase in the amount of underlying collagen tissue. The scar usually acquires a lighter color because of decreased vascularity. It is a permanent mark after a wound heals, a visible sign that indicates a disruption in the integrity of the epidermis and dermis. Scars are infrequently found in the oral cavity but may be of any shape or size. |
| sessile | describing a tumor or growth whose base is the widest part of the lesion. |
| sinus tract | an abnormal passageway that leads from a suppurative cavity, cyst, or abscess to the surface of the skin (epidermis). |
| slough | a mass of dead tissue. |
| stellate | pointed, shaped like a star. |
| telangiectasia | a vascular lesion caused by permanent dilatation of a small, superficial blood vessel. |
| ulcer | lesion characterized by the loss of the surface epithelium and frequently some of the underlying connective tissue. It often appears depressed or excavated. |
| verrucous | describing a tumor or growth that exhibits a rough, warty surface. |
| wheal | an edematous papule or plaque that results from acute extravasation of serum into the upper dermis. Usually pale red, pruritic, and of short duration; they are often seen in allergic individuals. |