The invention relates to a plunger-stopper (510) comprising a cylindrical body (511) having a front axial side closed by a front wall (513), said hollow cylindrical body (511) comprising an outer surface provided with at least one secondary sealing profile (610), said front wall (513) comprising a front axial outer surface (631) provided with a coating (635), advantageously an ethylene tetrafluoroethylene film, said front wall (513) comprising along the radially outer edge thereof a primary sealing profile (630), said front wall (513) and said hollow cylindrical body (511) being made of different materials, said hollow cylindrical body (511) being overmolded on said front wall (513), said front axial outer surface (631) of said front wall (513) comprising a deformation profile (633) arranged inside said primary sealing profile (630) of said front wall (513), said deformation profile (633) being suitable for deforming radially to facilitate insertion and/or sliding of said plunger-stopper (510) in a syringe body.Bouchon-piston (510) comportant un corps cylindrique (511) ayant un côté axial avant fermé par une paroi frontale (513), ledit corps cylindrique creux(511) comportant une surface externe pourvue d'au moins un profil d'étanchéité secondaire (610), ladite paroi frontale (513) comportant une surface externe axiale frontale (631 ) pourvue d'un revêtement (635), avantageusement un film en éthylène tétrafluoroéthylène, ladite paroi frontale (513) comportant sur son bord radialement externe un profil d'étanchéité primaire (630), ladite paroi frontale (513) et ledit corps cylindrique (511) étant réalisés avec des matériaux différents, ledit corps cylindrique creux (511) étant surmoulé sur ladite paroi frontale (513), ladite surface externe axiale frontale (631) de ladite paroi frontale (513) comportant un profil de déformation (633) disposé radialement à l'intérieur dudit profil d'étanchéité primaire (630) de ladite paroi frontale (513), ledit profil de déformation (
