Thermal injuries are classified based on their cause, such as flame, scald, electrical, or chemical contact. A cigarette burn is a specific type of contact burn resulting from the localized, high-temperature heat of a lit cigarette tip applied to the skin. This concentrated thermal energy creates a unique injury pattern that is visibly distinct from other types of burns.
Immediate Physical Characteristics
A fresh cigarette burn typically presents as a circular or slightly oval lesion, closely matching the diameter of a lit cigarette (5 to 10 millimeters across). This precise, uniform margin is a direct consequence of the steady, concentrated thermal contact.
The center of the wound, which has suffered the most intense heat, exhibits a phenomenon called coagulation necrosis. This process causes the skin proteins to denature and the tissue to die, resulting in a firm, dry, and often depressed central area that appears pale white, yellow, or even charred black. This discoloration signifies a full-thickness, or third-degree, burn in the central zone, meaning all layers of the skin have been destroyed.
Surrounding the necrotic center is a ring of less severely damaged tissue, known as the zone of stasis, and an outermost ring of redness, or erythema. The deep nature of the central injury often destroys the local nerve endings, potentially making the core of the fresh burn relatively painless despite the surrounding inflammation. This pattern of a small, deep, “punched-out” lesion with a distinct border is the hallmark of the injury in the first 24 to 48 hours.
Appearance During Healing and Scar Formation
Over the deeply necrotic center, a hard, dark crust, known as an eschar, forms as the dead tissue dries out. This eschar is typically dark brown or black and serves as a natural protective barrier over the underlying wound bed.
The eschar will gradually separate from the healthy tissue underneath, a process called sloughing, which can take several weeks due to the depth of the initial burn. Once the eschar has detached, it leaves behind an open ulceration that must heal by secondary intention, resulting in the formation of scar tissue. Because the injury destroys the entire thickness of the skin, including the dermal layer, scarring is the expected outcome.
The final healed mark is often a permanent, circular, and depressed scar known as an atrophic scar. This sunken appearance occurs because the body is unable to fully regenerate the lost dermal tissue and underlying fat. The scar tissue itself may display irregular pigmentation, with the circular border frequently outlined by post-inflammatory hyperpigmentation (darkening) or the center showing hypopigmentation (lightening), which further defines the initial injury’s outline.
Distinguishing Features from Other Thermal Injuries
The most telling feature is the remarkable uniformity of the lesion’s shape and size. Accidental contact with a hot surface, like a stove or iron, often results in an irregular shape that reflects the object’s geometry, but the cigarette burn is almost perfectly circular or oval.
Unlike scald burns, which are caused by hot liquids flowing across the skin, the cigarette burn does not exhibit any splash marks, runoff patterns, or diminishing severity away from the point of contact. Scalds tend to be less uniform in depth, with the burn severity decreasing as the liquid cools while running down the body. The cigarette burn, by contrast, maintains a consistent, deep destruction across its entire small surface area.
The disproportionate depth compared to the small surface area is the most specific identifying factor. While many accidental contact burns are superficial or partial-thickness, the concentrated heat of a cigarette tip held against the skin delivers enough thermal energy to cause a full-thickness injury in a very small spot. This combination of a small, distinct, and deep mark is what makes the visual identification of a cigarette burn possible.