CONSISTENCY AND SOFTNESS OF SOFT LINERS

Consistency is evaluated by an initial now test that allows the clinic ian to select the material of choice for relining procedures according to the size and shape of the ridge and the condition of the soft tiss ue, In this study, the consistency of four autopolymerized soft liners was compared and tested to determine whether they meet the new Intern ational Standards Organization (ISO) 10139-1 specifications. Softness, assessed with a Shore A durometer, was compared with that of two heat -cured silicone soft liners, because the latter are known for their st eady softness over long periods of time. The consistencies of all four autopolymerized soft liners complied with ISO specifications and thei r disk diameter ranged hom 41.3 to 72.2 mm. The softness of all four s oft liners changed with time, unlike the silicones whose softness rema ined consistent. Softness readings varied significantly with sample th ickness and indicated the need to develop criteria for measuring softn ess properties and determining the minimal thickness required for clin ical performance.