Hello Veronica,
our recommendation is that the ObjectScope should be opened/obtained based on demand by the page. The scope is a fairly light weight instance and fast to create. My personal recommendation is to use a getter property which obtains a scope when it had not been obtained before for this page (page field then, or master page field).
The only difficulty is to Dispose() the scope when no longer needed, but this can easily be achieved in the overridden Dispose() of the page or master page.
All the best,
Thomas
the Telerik team
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