An observational study in Osteoradionecrosis, Radiotherapy and Risk Factors, sponsored by AO Innovation Translation Center. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-23.
Sponsored by AO Innovation Translation Center · Observational
Osteoradionecrosis (ORN) of the jaw is a serious complication that can occur after radiation therapy for head and neck cancers, including oral cavity cancer (OCC). ORN happens when jawbone tissue dies and fails to heal, often triggered by dental issues like tooth extractions or poorly fitting dentures. Symptoms can include exposed bone, pain, difficulty opening the mouth, trouble swallowing, and even jaw fractures-leading to major physical and emotional challenges.
The likelihood of ORN varies widely, from less than 1% to over 50% in head and neck cancer patients. For OCC specifically, studies report rates from 4% up to 25%. Treatment depends on how much bone is affected and can range from medication to major surgery.
Risk factors include radiation dose, tumor location, oral health, dental extractions, lifestyle habits (like alcohol use), and other health conditions. Poor oral hygiene, high radiation doses, and alcohol use are among the most common risks. However, current data on OCC patients is limited and often not broadly applicable.
This study will retrospectively examine what increases the risk of ORN in OCC patients who received radiation therapy before or after surgery. Using data from multiple international centers, it aims to identify patterns and provide globally relevant insights. The results will help guide prevention strategies and create evidence-based guidelines to reduce ORN and improve long-term outcomes for these patients.
24 studies on the registry are indexed under Osteoradionecrosis; 8 are open to participants now.
This study's planned enrollment of 1,000 is above the median of 140 across 10 observational studies indexed under Osteoradionecrosis.
Browse Osteoradionecrosis studies →AO Innovation Translation Center is the lead sponsor of 32 studies on the registry; 11 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Patients will be selected from the primary care center where the patients received their initial treatment and followed up for at least 24months
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Developed clinically and radiographically or histologically confirmed osteoradionecrosis (ORN) of the jaw following radiotherapy.
No clinical, radiological, or histological diagnosis of ORN during the follow-up period.
Development of osteoradionecrosis (ORN) of the jaw
The primary outcome is the development occurrence (yes/no) of ORN after completion of pre- and/or postoperative RT. The objective is to identify and evaluate patient-, tumor-, treatment-, and region-related risk factors associated with the development of ORN across multiple geographic regions. Scoring Scale: The primary endpoint will be treated as a binary variable: 0 = No ORN 1 = Development of ORN Time to ORN onset (interval between completion of RT and clinical diagnosis of ORN) will also be recorded for time-to-event analyses.
Time frame: After completion of pre-and/or postoperative radiotherapy up to 24 months
Incidence of ORN Across Geographic Regions
To compare the incidence rates across geographical regions, namely between the Eastern and Western world, and High-Income Countries versus Low and Middle-Income Countries.
Time frame: After completion of pre-and/or postoperative radiotherapy up to 24 months
Severity of ORN by Tumor Characteristic
To evaluate the variability in the severity of osteoradionecrosis (ORN) based on primary tumor site (eg, tongue, floor of mouth, oral tongue, buccal mucosa, gingiva), histological tumor type (eg, adenoid cystic carcinoma, squamous cell carcinoma), and tumor characteristics including size, clinical stage (T1-T4), overall stage (III-IVA), and nodal status (N0, N1-2B, N2C, N3
Time frame: After completion of pre-and/or postoperative radiotherapy up to 24 months
Association between radiotherapy dose and ORN severity
To investigate the association between radiotherapy dose parameters (total dose and duration) and the severity grade of ORN among patients who develop ORN. Is there a correlation between increased radiation dose and duration and the severity of the condition?
Time frame: After completion of pre-and/or postoperative radiotherapy up to 24 months
Incidence and severity comparison of preop vs. postop RT
To compare the incidence and severity of ORN in patients undergoing preoperative versus postoperative radiotherapy
Time frame: After completion of pre-and/or postoperative radiotherapy up to 24 months
Incidence comparison across RT modalities
To compare the incidence ORN across different radiation modalities, including intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT), and conventional three-dimensional conformal radiotherapy (3D-CRT)
Time frame: After completion of pre-and/or postoperative radiotherapy up to 24 months
To determine whether the mandible is more susceptible to ORN than the maxilla, or vice versa.
To determine whether the mandible is more susceptible to ORN than the maxilla, or vice versa.
Time frame: After completion of pre-and/or postoperative radiotherapy up to 24 months
Complication evaluation with pre- or postop RT
To evaluate potential complications associated with preoperative and postoperative radiotherapy
Time frame: After completion of pre-and/or postoperative radiotherapy up to 24 months
To analyze the influence of pre-radiotherapy dental extractions and oral hygiene status on the risk of developing ORN
To analyze the influence of pre-radiotherapy dental extractions and oral hygiene status on the risk of developing ORN
Time frame: After completion of pre-and/or postoperative radiotherapy up to 24 months
To examine the variability in ORN incidence and severity between patients who undergo dental extractions before versus after the completion of RT
To examine the variability in ORN incidence and severity between patients who undergo dental extractions before versus after the completion of RT
Time frame: After completion of pre-and/or postoperative radiotherapy up to 24 months
No study locations are listed for this record.
Plan to share: Undecided
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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AO Innovation Translation Center