Study of the Use of Methoxyflurane vs Placebo in the Management of Pain in Oral and Dental Emergencies in Adults: METODO (METhoxyflurane in ODOntology) (METODO)

June 10, 2026 updated by: University Hospital, Brest

Prospective Double-blind Randomized Comparative Study of the Use of Methoxyflurane vs Placebo in the Management of Pain in Oral and Dental Emergencies in Adults: METODO (METhoxyflurane in ODOntology)

With a chronic shortage of dentists in some regions, and an increase in life expectancy and living conditions, the number of patients admitted to oral health emergencies is on the rise. Pain is the main reason for consultation, and is particularly exacerbated in the orofacial sphere. Dental pain has several etiologies: infectious, inflammatory or traumatic accidents.Beyond the ethical aspects of acute pain management, pain relief is a real objective. Despite prioritization systems, patients can wait a long time in an unsettled environment, with tired and sometimes aggressive patients. Numerous recommendations exist to improve analgesia in emergency departments, but there are still difficulties in effectively and rapidly managing acute dental and orofacial pain. To meet this demand and facilitate the treatment process, an alternative solution using methoxyflurane (Penthrox®) could be considered. This product, mainly intended for emergency services, has been approved in Europe since 2016 for the "emergency relief of moderate to severe pain associated with trauma in conscious adult patients". Thus, it would be interesting to assess the value of methoxyflurane (Penthrox®) in the management of pain in oral emergencies as a wait-and-see solution.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
190

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • France
      • Brest, France, 29200
        • CHU Brest

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Adult patient (> 18 years)
  • Conscious patient consulting an oral emergency department with pain assessed as moderate to severe NRS greater than or equal to 4
  • Patient has social security affiliation or who beneficiary of such social security
  • Patients who have given informed consent

Exclusion Criteria:

  • Patients with a history of allergy to methoxyflurane or any of the components of Penthrox (take into account family history of severe allergic reactions)
  • Patients with a history of malignant hyperthermia (known or genetic predisposition)
  • Patients with hepatic impairment after use of methoxyflurane or halogenated hydrocarbon anesthesia
  • Patients with severe renal Failure
  • Patients with altered level of consciousness, whatever the cause: head trauma, drug or alcohol abuse
  • Patients with cardiovascular instability or respiratory depression
  • Pregnant or breast-feeding patients. Therefore, a urine pregnancy test will be performed for all patients of childbearing age eligible to participate in the study
  • Patients under legal protection (guardianship and curatorship) or deprived of liberty
  • Patients unable to speak or read French fluently, unable to understand the principle of a numerical scale, anxiety and satisfaction questionnaires, and unable to cooperate with tests

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Placebo Comparator: control group
Drug: control group (standard of care + placebo).
standard of care + placebo
Experimental: Experimental group
Drug: Experimenta group (standard of care + Methoxyflurane).
standard of care + Methoxyflurane

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Pain assessed by a numerical rating scale at baseline and at T=15min post-treatment
Time Frame: 15 minutes post-treatment
Pain at baseline and at T=15min post-treatment, measured using a numerical rating scale (NRS) graded from 0 to 10 (0 means no pain, 10 means maximum imaginable pain)
15 minutes post-treatment

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Pain intensity <4/10 (yes/no) at T=15min after treatment
Time Frame: 15 minutes post-treatment
15 minutes post-treatment
Pain assessed by a numerical rating scale at T=7min (immediate efficacy)
Time Frame: 7 minutes post-treatment
Pain at T=7 min post-treatment, measured using a numerical rating scale (NRS) graded from 0 to 10 (0 means no pain, 10 means maximum imaginable pain)
7 minutes post-treatment
Pain assessed by a numerical rating scale at T=40 minutes after treatment and just prior to treatment by the practitioner (persistence of efficacy)
Time Frame: 40 minutes post-treatment
Pain at T=40 min post-treatment, measured using a numerical rating scale (NRS) graded from 0 to 10 (0 means no pain, 10 means maximum imaginable pain)
40 minutes post-treatment
Assessment of Anxiety
Time Frame: Just before chairside treatment
Anxiety, measured at inclusion and just before chairside treatment using a translated and adapted anxiety questionnaire (MDAS: modified dental anxiety scale) Total score is a sum of all five items, range 5 to 25: 5 means not anxious, 25 means extremely anxious
Just before chairside treatment
Measuring the amount of local anesthetic used during treatment
Time Frame: 1 day
1 day
Post-care satisfaction questionnaire
Time Frame: End of the study (up to 1 day)
Answers to 4 questions on overall satisfaction of the care, ranging from very dissatisfied to very satisfied
End of the study (up to 1 day)
Pain assessed by a numerical rating scale at T=15min according to analgesic associated with methoxyflurane
Time Frame: 15 minutes post-treatment
Pain at T=15 min post-treatment, measured using a numerical rating scale (NRS) graded from 0 to 10 (0 means no pain, 10 means maximum imaginable pain)
15 minutes post-treatment
Pain assessed by a numerical rating scale at T=15min according to type of emergency
Time Frame: 15 minutes post-treatment
Pain at T=15 min post-treatment, measured using a numerical rating scale (NRS) graded from 0 to 10 (0 means no pain, 10 means maximum imaginable pain)
15 minutes post-treatment

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University Hospital, Brest

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
October 14, 2024

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
October 3, 2025

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
October 3, 2025

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
December 15, 2023

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
July 9, 2024

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
July 10, 2024

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
June 12, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
June 10, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
June 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 29BRC23.0024 (METODO)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

All collected data that underlie results in a publication

IPD Sharing Time Frame

Data will be available beginning five years and ending fifteen years following the final study report completion.

IPD Sharing Access Criteria

Data access requests will be reviewed by the internal committee of Brest UH. Requestors will be required to sign and complete a data access agreement

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings