Osteoradionecrosis is an inflammatory bone condition that occurs after exposure to therapeutic radiation doses, usually for head and neck cancers. It is characterized by exposed bone for at least 3 months after radiation therapy. The mandible is most commonly affected due to its anatomy and low vascularity. Management includes conservative approaches like antibiotics and debridement to maintain bone integrity and prevent infection, as well as hyperbaric oxygen therapy to reduce hypoxia and improve healing. Prevention involves dental work before radiation and careful oral hygiene during and after treatment.

2. Osteoradionecrosis
Guided by :
Dr. Krushna pateria,
Dr. Pooja wankhade
Presented by :
Mohammad Naved

3. Contents :
 Introduction
 Definition
 Etiology
 Clinical features
 Radiographic examination & features
 Differential diagnosis
 Management
 Prevention

4. Introduction
 This is inflammatory condition of bone.
 The high doses of radiation used in radiotherapy
reduce drastically the vascularity and reparative
powers of bone. The mandible is particularly
susceptible.
 Subsequent trauma (e.g. tooth extraction)
or infection may produce osteomyelitis with
rapid destruction of the irradiated bone,
sequestra formation and poor healing.

5.  It is characterized by presence of exposed bone for a
period of at least 3 months occurring at any time after
delivery of the radiation therapy.

6. Definition
 Osteoradionecrosis refers to an inflammatory
condition of bone (osteomyelitis) that occurs after the
bone has been exposed to therapeutic doses of
radiation usually given for a malignancy of the head
and neck region.

7. Etiology
 Doses above 50 Gy usually are required to cause this
irreversible damage.
 Bone that has been irradiated is hypocellular and
hypovascular.
 Dental extraction and denture trauma after radiation
therapy.

8. Clinical features
 Mandible is commonly affected than maxilla due to
microanatomy & less vasculature.
 Posterior mandible is commonly affected than anterior
portion because of radiation treatment for tumors in
this region.

9.  Loss of mucosal covering & exposed bone are hallmark
of Osteoradionecrosis.
 Pain may or may not be present with swelling and
drainage extraorally..
 The exposed bone become necrotic as result of loss of
vascularity from periosteum & sequestra.

10. Radiographic Features
 CT imaging is modality of choice.
 Early changes in bone: is well defined area of bone
resorption within the outer cortical plate of
mandible.

11.  Later changes: lytic or sclerotic or mixture
 Location : Commonly posterior mandible
 Periphery : ill defined
 Internal structure : A range of bone formation and
resorption occur. The bone pattern is granular.

12.  Effects on surrounding structures : in rare cases
stimulated periosteal bone formation resulting in
bone formation on outer cortex.
 In the alveolar processes of maxilla and mandible there
is irregular widening of periodontal membrane space.

13. EARLY LATER

15. Differential diagnosis
 Bone resorption stimulated by high level irradiation :
Differentiated by absence of exposed bone.
 Chronic osteomyelitis : history of radiation therapy.

16. Management
1. Conservative approach to maintain the integrity of
inferior border of mandible, keeping the site free of
infection , and patient free of pain is more successful.
 Adminstration of Antibiotics , rinisng
 Sequestrectomy, local debridement
 Use of narcotic analgesics , hydration, nutrition
 Ultrasound therapy can be used.

17. 2. Radical method
 HBO therapy
 Local debridement , sequestrectomy
 Mouth rinsing

18. 3. Hyperbaric O2 therapy : breathing 100 % oxygen
through facemask at 2.4 absolute atmospheric
pressure for 90 minutes 5 days week.
HBO reduced the hypoxia and increase healing by
increase in arterial and venous O2 tension.

19. Prevention of ORN
 Pre irradiation care :
Extraction of periodontally compromised tooth which
is in direct beam of radiation.
 During therapy : mouth rinse with 0.2 %
chlorhexidine.
 Post irradiation care :
Avoidance of denture use. Use of salivary substitutes.

20. Summary
 Osteoradionecrosis is caused by bone exposed to
irradiation therapy above 50 Gy.
 It is a radiation induced, non healing, hypoxic wound.
 Its prevention and treatment are possible.
 HBO therapy , Sequestrectomy are some methods of
treatment.

21. References
1. White and pharoh
2. Rajiv M borle. Textbook of oral and maxillofacial
surgery. Jaypee. 1st edition 2014.

22. Thank you