Diagnosis of third-degree burns is easier than second-degree burns. 

The scald third-degree wound is pale with no blood supply and almost no exudate. Pain sensation is lost or reduced. 

Flame burns wound has a carbonized epidermis which can be adherent to the dermis. 

The wound surface is lower than surrounding normal skin surface, there is a loss of pain sensation, and no exudate appears at the exudation stage. 

After treatment with MEBT/MEBO, sparse exudate can be seen. 

After the exudation stage, the necrotic tissue begins to liquefy, but this occurs much slower than that of deep second-degree burns wounds.

Liquefaction completes in 15–20 days and granulation tissue appears in the wound. 

The superficial third-degree burn with thermal injury reaching the subcutaneous layer may heal by skin regeneration. 

A small area of deep third-degree burns wound (diameter <18 cm) with thermal injury reaching the muscle layer may heal without skin grafting but with scar formation. 

Large deep third-degree burns wound needs skin grafting. 

Pediatric third-degree burns wound is usually dark and red in color. 

When conventional surgical burns therapy is applied, it is difficult to estimate burn depth accurately, especially to distinguish deep second-degree and third-degree burns.