Microstructural changes in the irradiated and osteoradionecrotic bone: a SEM study

P. Sridhar Reddy, Kaapo Villikka, Bina Kashyap, Hannah Dekker, Engelbert A. J. M. Schulten, Jopi J. W. Mikkonen, Mikael Turunen, Arto P. Koistinen, Nathalie Bravenboer, Arja M. Kullaa

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

Radiation exposure is a major health concern due to bone involvement including mandible, causing deleterious effects on bone metabolism, and healing with an increasing risk of infection and osteoradionecrosis. This study aims to investigate the radiotherapy-induced microstructural changes in the human mandible by scanning electron microscopy (SEM). Mandibular cortical bone biopsies were obtained from control, irradiated, and patients with osteoradionecrosis (ORN). Bone samples were prepared for light microscopy and SEM. The SEM images were analyzed for the number of osteons, number of Haversian canal (HC), diameter of osteon (D.O), the diameter of HC (D.HC), osteonal wall thickness (O.W.Th), number of osteocytes, and number of osteocytic dendrites. The number of osteons, D.O, D.HC, O.W.Th, the number of osteocytes, and osteocytic dendrites were significantly decreased in both irradiated and ORN compared to controls (p <.05). The number of HCs decreased in irradiated and ORN bone compared to the control group. However, this was statistically not significant. The deleterious effect of radiation continues gradually altering the bone quality, structure, cellularity, and vascularity in the long term (>5 years mean radiation biopsy interval). The underlying microscopic damage in bone increases its susceptibility and contributes further to radiation-induced bone changes or even ORN.
Original languageEnglish
JournalUltrastructural pathology
Early online date2023
DOIs
Publication statusE-pub ahead of print - 2023

Keywords

  • Irradiation
  • mandible
  • osteocytes
  • osteoradionecrosis
  • scanning electron microscopy

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