Dental Education Guide

Patient factors

Head & Neck Radiation Therapy and Dental Implants

Prior radiation to the jaws changes implant biology fundamentally. This guide explains the dose thresholds, the risk of osteoradionecrosis, and how implant timing is altered.

Reading time
8–10 min
Medically reviewed
Reviewed by a licensed dentist
Last updated
2026-06-01

Written by

Dental Education Guide Editorial Team

Editorial team

Medically reviewed by

Medical Review Board (External Clinical Advisors)

Medical review

Editorial review

Evidence Review Lead

Editorial review

Last reviewed:
2026-06-01
Last updated:
2026-06-01
Reading time:
8–10 min
Version:
1.0

Overview

Therapeutic head-and-neck radiation produces lasting changes in the jawbone: hypovascular, hypocellular, hypoxic tissue that heals poorly and is vulnerable to osteoradionecrosis (ORN). For implant patients, this means timing, dose, and site planning matter much more than in healthy bone.

Dose thresholds that matter

  • < 50 Gy at the implant site: implant survival is reduced but acceptable in most series.
  • 50–60 Gy: meaningful drop in survival; planning is more conservative.
  • > 65 Gy: substantially elevated risk of ORN and failure; many surgeons consider this a relative contraindication.

Dose information should come from the radiation oncology report, mapped against the implant site rather than the jaw as a whole. Modern IMRT plans often spare parts of the mandible that older 2D plans irradiated heavily.

Timing of implant placement

Two windows are commonly used: (1) immediately at the time of ablative surgery, before radiation begins, with implants left submerged through treatment; or (2) at least 12 months after completion of radiation, allowing tissues to stabilise. The intermediate window (1–12 months post-radiation) is generally avoided because the irradiated tissues have not yet plateaued.

Hyperbaric oxygen — is it useful?

The role of perioperative hyperbaric oxygen (HBO) in irradiated implant patients remains debated. Marx-style protocols are still used in some centres, but the most rigorous trial (HOPON) did not demonstrate a meaningful reduction in ORN. HBO is no longer universally recommended and should be discussed centre-by-centre.

A radiation-aware plan

  • Obtain the radiation oncology summary (total dose, fractions, fields).
  • Map planned implant sites against the actual dose distribution where possible.
  • Atraumatic technique, primary closure, longer healing periods (often 6–9 months).
  • Antibiotic prophylaxis per local protocol; rigorous oral hygiene support.
  • Long-term maintenance every 3 months, with low threshold to image any symptomatic site.

Frequently asked questions

Scientific references

  1. 1. Moraschini V, Poubel LA, Ferreira VF, Barboza ES. (2015). Evaluation of survival and success rates of dental implants reported in longitudinal studies with a follow-up period of at least 10 years: a systematic review. Int J Oral Maxillofac Surg. 44(3):377-88. View source
  2. 2. American Dental Association. (n.d.). Oral Health Topics: Implants. American Dental Association. View source