The Animal Study For The Regeneration Of Mucoperiosteal Tissue Of Hard Palate With Absorbable Biofilm

Different surgical flap techniques are applied to reconstruct the palatal defects caused by cleft palate or trauma in clinics. The flap techniques have some deficiencies. In this study the PDLLA films are implanted into the defect area to guide the regeneration of mucoperiosteal tissue in the goat palates. This study is to evaluate the use of PDLLA biofilm as guide to regeneration of the mucoperiosteal tissue, and to search the new method of cleft palate operation.PDLLA was made into 0.5mm thick film. 12 goats as experimental animals were divided into experimental group and control group (6 animals in each) at random. 18.0×16.0mm~2 rectangle defect(including mucoperiosteal and bone tissue) were made in mid part of hard palates. PDLLA biofilms were implanted into the experimental group defects. The same size tissues in the control group were removed without the PDLLA biofilms implanted. The tissue regeneration in the defects wasobserved and measured 2,4,6,8,12 weeks after operation. The structure of regenerating tissue was analyzed by histology 2,4,6,8,12 weeks.The PDLLA biofilms were observed through SEM and TEM.The results are as the following: the mucoperiosteal tissue in experimental group regenerated along the PDLLA biofilms and the mucoperiosteal defects were closed in 7 weeks. The PDLLA biofilms degenerated in the tissue. No obvious rejection reaction could be observed. The soft and hard tissue did not close up in control group in 7 weeks. The structure of regenerating tissue was similar with the normal mucous tissue.It is conclusioned that ,PDLLA biofilms can guide the regeneration of mucoperiosteal tissue to close the palatal defect . PDLLA biofilms can degenerate after the soft tissue regeneration.This method have the clinical application value.