Liquid and sterile composition, dedicated to an administration in or through the skin and / or lips, said composition comprising in a physiologically acceptable medium at least one photoreticulable compound, said compound comprising at least one activated photodimerizable group having at least a double bond activated and chosen from: a) photodimerizable groups that carry a stilbazolium function of formula (Ia) or (Ib): ** Formula ** where - R represents the hydrogen atom, a C1-C4 alkyl group or C1-C4 hydroxyalkyl. - R 'represents the hydrogen atom or a C1-C4 alkyl group, and - X- designates an ion chosen from the chlorides, bromides, iodides, perchlorates, tetrafluoroborates, methylsulfate, phosphates, sulfates, methanesulfonates, p-toluenesulfonate ions. where - R "designates a bivalent alkylene radical having 2 to 8 carbon atoms, - R 'represents the hydrogen atom or a C1-C4 alkyl group, and - X- having the same meaning as described for the formula (Ia) above b) the photodimerizable groups that carry a styrylazolium function of formula (II): ** Formula ** in which: - R1 designates the hydrogen atom, a C1-C4 alkyl or C1-hydroxyalkyl group C4, - A designates a sulfur atom, an oxygen atom, or an NR 'or C (R') 2, R ', R' group representing the hydrogen atom or a C1-C4 alkyl group, and - X - having the same meaning as described for the preceding formula (Ia), the photodimerizable group (s) being carried by a partially or fully hydrolyzed polyvinylacetate polymer, a polysaccharide or a polyvinyl alcohol.Composición líquida y estéril, dedicada a una administración en o a través de la piel y/o los labios, dicha composición que comprende en un medio fisiológicamente aceptable al menos un compuesto fotorreticulable, dicho compuesto que comprende al menos un grupo fotodimerizable activado que posee al menos un doble enlace activado y elegido entre: a) los grupos fotodimerizables que llevan una función estilbazolio de fórmula (Ia) o (Ib):**Fórmula** donde - R representa el áto
