When should hyperbaric oxygen (HBO) therapy be started after dental extraction in high-risk patients?

Hyperbaric Oxygen Therapy Timing After Dental Extraction in High-Risk Patients

Routine prophylactic hyperbaric oxygen (HBO) therapy is not recommended before dental extractions in patients who received prior head and neck radiation therapy, but when indicated, it should be administered as 20 sessions before extraction and 10 sessions after extraction. 1

Risk Assessment for HBO Therapy

The need for HBO therapy should be determined based on:

1. Radiation exposure history:

   • Patients who received >50 Gy to the mandible or maxilla are at highest risk 1
   • Areas where substantial volume of mandible/maxilla received >50 Gy may benefit from HBO 1

2. Time since radiation:

   • Longer time since radiation is associated with higher risk of osteoradionecrosis (ORN)
   • Risk increases from 6% if within 1 year of radiation therapy to 16% if ≥5 years after radiation therapy 1

HBO Protocol When Indicated

When HBO is deemed necessary for high-risk patients:

• Pre-extraction: 20 sessions at 2.4 atmospheres for 80-90 minutes daily 1, 2
• Post-extraction: 10 sessions following the same protocol 1, 2

This protocol has been studied in multiple clinical trials, though evidence for its efficacy is limited 1, 2.

Alternative and Adjunctive Approaches

For high-risk patients, consider these evidence-based alternatives:

1. Pentoxifylline and tocopherol:

   • Start at least 1 week before procedure
   • Continue for 4 weeks after procedure or until socket healing
   • Dosage: pentoxifylline 400mg twice daily and tocopherol 1,000 IU once daily 1

2. Perioperative antibiotics:

   • Recommended for patients at higher risk for ORN 1
   • Example: amoxicillin 1 hour before procedure and three times daily for 5 days after 1, 2

3. Antiseptic mouth rinses:

   • Chlorhexidine gluconate (0.12% or 0.2%) twice daily until healing 1
   • Start before procedure and continue until sufficient healing 1

Evidence Analysis and Limitations

The most recent high-quality evidence challenges the routine use of HBO therapy:

• A randomized controlled trial (HOPON) with 144 patients found no significant difference in ORN incidence at 6 months between HBO and control groups (6.4% vs. 5.7%) 2
• This contradicts older studies that reported higher ORN rates (14-30%) without HBO 2

However, HBO may still benefit specific high-risk subgroups:

• It improves the probability of dental socket healing within irradiated areas 1
• Patients with radiation dose >50 Gy to substantial volumes of mandible/maxilla may benefit 1

Important Considerations and Contraindications

Before initiating HBO therapy, consider:

• Cardiac status: Patients with decompensated heart failure (NYHA class IV) should not undergo HBO 3
• Recent cardiac events: HBO should be avoided after recent cardiac arrest 3
• Respiratory conditions: Patients with severe respiratory compromise or history of spontaneous pneumothorax are at increased risk of complications 3
• Seizure disorders: Anti-seizure medications should be optimized before treatment 3

Monitoring During HBO Treatment

For patients receiving HBO therapy:

• Monitor for signs of bleeding or hematoma formation
• Track vital signs for indications of internal bleeding
• Perform post-procedure assessment of the access site 3

Key Takeaway

While routine prophylactic HBO is not recommended for all patients with prior head and neck radiation therapy, it may benefit selected high-risk patients. When used, the established protocol is 20 pre-extraction and 10 post-extraction HBO treatments at 2.4 atmospheres for 80-90 minutes per session.