Purpose: Although the usefulness of polyglycolic acid (PGA) sheet for wound dressing has been recently reported, its histopathological effect on wound healing is not completely elucidated. This pilot study focused on the neo-epithelium formation and the remaining inflammation.Methods: Full-thickness defects of 8 mm were created on the back of seven-week-old rats. Four rats were divided into the control (raw surface) group and the PGA group, in which the wounds were covered with a PGA sheet. The wounds were assessed on days seven and 12 after wound creation. The length of neoepithelium on day seven was measured by referring to Masson's trichrome (MT) and α-smooth muscle actin (α-SMA) staining. The remaining inflammation on days seven and 12 was assessed with ionized calciumbinding adapter molecule 1 (Iba-1) staining. Results:The average values of neo-epithelium length on day seven measured by referring to the borderline between MT staining and α-SMA expression were 959.2 μm in the control group and 582.2 μm in the PGA group. The number of Iba-1-positive cells on day 12 was significantly higher in the PGA group than in the control group.Conclusions: To assess the neo-epithelium length and the remaining inflammation, the α-SMA, MT, and Iba-1 staining may be appropriate.

Pain is a problematic symptom in patients with osteonecrosis of the jaws (ONJ). Effective pain management in patients with advanced ONJ still remains an unresolved issue. This case series report presents three patients who were referred to the pain clinic for treatment of intractable pain caused by ONJ. Two patients received mandibular nerve blocks and achieved pain relief. After referral to the pain clinic, these two patients underwent segmental mandibulectomy for ONJ. In the third patient, the effect of pain control was limited. Appropriate cooperation between the oral and maxillofacial surgeon and the pain specialist is essential for pain management in patients with advanced ONJ who experience intense pain.