It is contamination (the tines of the fork endings as extinguished heads of matches ) with an identity by temporal contiguity (extinguished heads-fire), an identity by semantic similarity (fire-burning), an identity by spatial contiguity (fork-swallowed food).

Then an other identity by temporal contiguity (Swallowed food-burning ), and finally a double identity by phonetic and semantic similarity (burning-heartburn), followed by an identity by negative emotional similarity (heartburn-ache) solved into a positive opposition (Maalox Plus. Contro il bruciore di stomaco / Maalox Plus. Against the heartburn)

An advertisement not simple, but fully coherent.