Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:The sulphate dehydrate part of the implant is gradually resorbed during 7–8 weeks and being replaced by ingrowing bone that remodels to form trabecular bone, supplied by the remaing hydroxyapatite nanoparticles thus incorporated in to the newly formed trabecular bone [8].
Category: