Oral surgical procedures occasionally require removal of the periosteum due to lesions,
and these raw bone surfaces are prone not only to infection but also to scar formation
during secondary healing. The objective of this study was to identify successful methods
for reconstruction using periosteal defect dressings. We created 1-cm2 defects
in the skin and cranial periosteum of 10-week-old male Wistar rats under isoflurane
anesthesia. The animals were assigned to three defect treatment groups: (1) polyglycolic
acid sheets with fibrin glue dressing (PGA-FG), (2) Spongel® gelatin sponge dressing (GS),
and (3) open wound (control). Postoperative wound healing was histologically evaluated at
2, 4, and 6 weeks. The moist conditions maintained by the GS and PGA-FG treatments
protected the bone surface from the destructive effects of drying and infection. Complete
wound healing was observed in the GS group but not for all animals in the PGA-FG and
control groups. Histologically, osteoblast proliferation on bone surfaces and complete
epithelialization with adnexa were observed in the GS group at 6 weeks after surgery. In
contrast, PGA sheets that had not been absorbed inhibited osteoblast proliferation and
delayed wound healing in the PGA-FG group. Wound surface dressings maintain a moist
environment that promotes wound healing, but PGA materials may not be suitable for cases
involving exposed periosteum or bone surfaces due to the observed scar formation and
foreign-body reaction.