抄録
Aim of study
To compare the effect on bone regeneration relative to maintenance period of PTFE
membrane in rabbit calcarial defects.
Materials and Methods
Eight adult New Zealand white female rabbits were used in this study. Four defects were
surgically made in their calvaria. Using a trephine bur, 4 'through and through' defects were
created and classified into 3 groups, which were consisted of control group(no graft),
experimental group 1(autogenous bone)and experimental group 2(deproteinized bovine bone;
OCS-BⓇ). The defects were covered with PTFE membrane(CytoplastⓇ). Membranes were
removed after 1, 2, 4 and 8 weeks post-GBR in each 2 rabbits. And then, all rabbits were
sacrificed, specimens were taken and observed histologically.
Results
Control group. After 1 week any new bone formation was not evident. After 2 weeks minimum
of bridge-shaped new bone are formed. After 4 weeks the defect was filled with new bone,
though the regenerated thickness was less than the adjacent bone. After 8 weeks the
new bone formation appears incomplete in the bony cavity, with invaded connective tissue
on the superficial surface.
Experimental group 1. At 1 and 2 weeks the defects were filled with new bone at adjacent
bone thickness, but connective tissue was invaded on superficial surface. At 4 and 8
weeks the new bone formation appears complete in the bone cavity without connective
tissue and the autogenous bone particle is blended with new bone.
Experimental group 2. At 1,2 and 4 weeks the defects were filled with new bone at
original bone thickness and appeared light concave on the surface that consists of
connective tissue. At 8 weeks the new bone formation appeared complete in the bone cavity
without connective tissue and new bone formation around deproteinized bovine bone
particle was appeared.
Conclusion
1) The use of graft material and membrane was necessary in GBR procedure.
2) When PTFE membranes were removed early, the most favorable bone
regeneration was revealed in experimental group I, followed by experimental group II
and control group.
3) On GBR, it is recommended that membrane should maintain for 4 weeks with
autogenous graft. As well, the use of xenograft need longer maintenance period than
autogenous bone.
