The interpositioning of various materials to complete suturectomy for the treatment of craniosynostosis has been used by many surgeons to prevent early postoperative reunion. Clear scientific proof for this procedure has not yet been obtained with any material, however. A previously described model of experimental craniosynostosis was employed to examine the effects of an interpositioned biodegradable polyglycolic acid (PGA) membrane on the growing skull of 14 newborn rabbits. Additional 11 newborn rabbits served as controls, as on their skulls only unilateral resection of the coronal suture was performed (experimental craniosynostosis). The skulls were examined for shape and histology up to 6 months of age. The 11 rabbits in the control group developed a unilateral deformity on their calvaria as demonstrated by dry-skull osteometry. The 14 rabbit skulls having the interpositioning of a PGA membrane done into the resection site at the time of unilateral suturectomy were found to have grown in a remarkably symmetrical fashion. The interpositioning of a PGA membrane therefore seems to prevent the formation of a skull deformity during growth as compared with early suturectomy alone.