Scanning and transmission electron microscopy demonstrates bacteria in osteoradionecrosis

Area of Science:

• Oral and Maxillofacial Surgery
• Infectious Diseases
• Microbiology

Background:

• Osteoradionecrosis (ORN) is characterized by hypoxic, hypovascular, and hypocellular bone.
• Previous studies using DNA-DNA hybridization indicated the presence of microorganisms in radionecrotic bone.
• The role of bacterial infection in ORN pathophysiology remains debated.

Purpose of the Study:

• To visualize microorganisms within radionecrotic bone tissue using electron microscopy.
• To investigate the association between microbial presence and osteoradionecrosis.
• To explore the potential for an infectious etiology in ORN.

Main Methods:

• Scanning and transmission electron microscopy were employed.
• Deep medullar specimens were obtained from 14 resected radionecrotic mandibles.
• Microscopic analysis focused on identifying bacterial and fungal presence.

Main Results:

• Microorganisms were detected in 64% (9 out of 14) of the studied specimens.
• Detected microorganisms included rods, spirochetes, and cocci, with rods being most prevalent.
• One sample also showed evidence of yeast (blastoconidia and pseudohyphae).

Conclusions:

• The study provides strong evidence for the association between microorganisms and osteoradionecrosis.
• These findings suggest that microbial presence may be a significant factor in ORN development.
• The results may necessitate a revision of the current understanding of ORN pathophysiology, including the consideration of infectious causes.