It depends on what is being studied…. If someone wants to prove that some material (injectable gel????) does not need a membrane, it should be tested both alone against covered by membrane...

What is the name of this gel that you're using to obtain a " membrane " ?

@Frernando . I am not intended to study GBR membrane would required or not . I am planning to study whether HAP nanoparticles incorporated chitin gels can aid in bone regeneration or not . My doubt was, Is GBR membrane will be used usually in cranial bone regeneration studies, along with the test material?

@ Marco . sir I am planning use only chitin gels. 

My doubt was, Is GBR membrane will be used usually in cranial bone regeneration studies, along with the test material?

I understood you are testing if there will be any soft tissue in-growth in the defect area filled with the gel system… so, the right model would be compare the "gel alone" x "gel with membrane"...

how would you cover the defect area? ie sutures or just without any material.ie will you depend  on the gel only and it will become an open wound???? l.i am afraid that if you depend on the gel only  and it does not harden you end up by granulation tissue similar to secondary wound healing  .the Guided bone regeneration method is good in that it will protect the gel and give you a product replacing the gel  and a chance to section and show the guided tissue as well as the new material . Researchers might  come back at you saying how did you know that the results you obtained were  be  from the GBR  ,and here you have to do a sham operation with out the  GBR  to satisfy the critics

I hope this helps

No!!! A membrane commonly collapses into the osteotomy preventing necessary space for regneration. See our publications.