Australian Dental Council (ADC) Practice Test

Pemphigus vulgaris is a serious autoimmune condition that is marked by the formation of bullae (large blisters) and erosions in various mucous membranes, including the mouth. This disease arises due to the production of autoantibodies that target desmogleins, which are proteins essential for the adhesion of epithelial cells. The result is a breakdown in the connections between these cells, leading to the formation of blisters that can rupture and result in painful erosions.

In the context of the other options, while bullous lichen planus can also present with lesions in the mouth, it typically involves a different type of inflammatory process and may not feature the same level of blistering. Erythema multiforme presents with target lesions on the skin and can have oral manifestations, but it does not primarily manifest as bullae or erosions. Oral melanoma is a malignant tumor of the oral mucosa and does not typically present with bullae or erosions as a primary characteristic. Thus, pemphigus vulgaris stands out clearly due to its distinctive clinical presentation.