Frequently Asked Questions (FAQs) About Mandibular Devices
A mandibular device, also known as a mandibular advancement device (MAD), is an oral appliance prescribed by a dentist, and designed to treat sleep apnea and snoring by repositioning the lower jaw slightly forward to keep the airway open during sleep.
The device pushes the lower jaw forward, preventing the collapse of soft tissues at the back of the throat, which can block the airway and cause snoring or sleep apnea.
Mandibular devices are typically recommended for patients with mild to moderate obstructive sleep apnea or those who cannot tolerate CPAP therapy. A sleep specialist or dentist can determine if you’re a candidate.
Most users find the device comfortablei after an initial adjustment period.
Some patients undergoing treatment with MADs can encounter early side effects, including dental discomfort, dry mouth, excessive salivation, and gum irritationii. However, these side effects are typically temporary, ranging from mild to moderate in severity, and rarely lead to discontinuation of MAD use.
A dentist specializing in sleep medicine takes impressions of your teeth to create a custom-fitted device tailored to your mouth and jaw structure.
It depends on your dental health. Consult your dentist to evaluate whether a mandibular device is suitable for your dental condition.
Many patients notice improvements in snoring and sleep quality quicklyiv. Long-term results for sleep apnea vary based on individual anatomy and adherence to use.
Possible side effects include temporary jaw discomfort, tooth movement, or changes in salivation. These are usually mild and can often be managed with adjustments by your dentist.
- After each night: rinse with lukewarm water (max 45°C) and clean with a soft toothbrush (no toothpaste or alcohol-based products). Then dry it thoroughly.
- Twice a week: use a antibacterial denture cleaner for deeper hygiene
Yes, the device is compact and portable, making them convenient to take with you.
With proper care, Narval CC devices should last about 3 years. Regular dental check-ups are recommended to assess wear and ensure it remains effective.
No, product adjustments can only be performed by a dental practitioner. Do not hesitate to reach out to your dental practitioner if needed.
Yes, mandibular devices are effective for reducing or eliminating snoring1 caused by airway obstruction, even in the absence of sleep apnea.
If the device no longer provides relief, consult your dentist or sleep specialist. They may adjust the fit, replace worn components, or suggest alternative treatments.
O2 ring set-up
Learn how to wear, operate and adjust your O2 ring for accurate and comfortable daily tracking.
Choose a finger that offers a snug, comfortable fit-neither too tight nor too loose. Wear the device on thumb finger, index finger as option in case of too tight for thumb. Try to move the device along the forefinger to find out the best fit. Avoid being loose. Loose wearing causes inaccurate measure. Do not use the middle finger; if too tight for thumb or forefinger, try little finger.
Wear the device on your finger, it will power on automatically. If can’t power on, charge you device first.
Take the device off your finger, it will power off automatically in a while if not connected to App.
Touch the key on the top of device, you can wake up the screen. You can also check time and battery with the touch key.
Device time will automatically sync with your phone’s time once connected to myNarval
The device can store last 4 sessions, up to 10 hours for each. Short spot checks can be conducted and the SpO2 will be displayed on the device screen.
Sessions below 60 minutes will not be displayed in the app.
Data Sync, Sharing & Bluetooth Help
Having trouble syncing, connecting or sharing your O2 ring data? Find step by step answers here.
Take off the O2 ring.
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- Open myNarval app, the data sync will initiate an automatic sync
- If automatically sync is not initiated, select “Sync Device” from the myNarval home screen to manually sync.
Note: If measurement time is less than 60 minutes, there will be no data.
This usually means the ring is still connected to another mobile device. Here’s how to fix it:
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- Turn off Bluetooth on any other phone or tablet that may have previously connected to the ring. Force the myNarval app to close on those devices.
- Then, on your phone, restart the myNarval app and try connecting again.
The ring can only connect to one device at a time. Disconnecting from others first will solve most pairing issues.
You can generate a PDF report directly from the app by going to the “Create PDF Report” section and downloading the report. Once downloaded, the PDF can easily be shared with your doctor or dentist to support your consultation.
This can occur if the ring is worn either too loosely or too tightly, preventing the sensor from consistently capturing reliable data. We recommend trying again for another night and ensuring the ring fits snugly but comfortably.
If it doesn’t fit well on your thumb, you can try wearing it on your index finger and adjust its position to find the best fit. Make sure it is not loose, as this can lead to inaccurate measurements. Don’t use the middle finger; if the ring is too tight on both the thumb and index finger, you may try the little finger instead.
Yes, rest assured: if the battery runs out during use, your data will still be saved.
To avoid any inconvenience, we recommend charging the device before the battery is completely drained. For best performance, please make sure the device is fully charged before each use. This helps ensure everything runs smoothly and your recordings remain fully reliable.
DO NOT PAIR in the system settings of your phone.
Open myNarval app and make sure Bluetooth is enabled on your phone and device’s battery is not out.
This means the Ring is still trying to stay connected to your phone. To turn it off, simply turn off Bluetooth on your phone and close the myNarval app. The O2Ring will automatically shut down after a short time.
Understanding the Data & Report
Get help with display issues, date and time setup, languages options, and other O2 rings setting.
It refers to the blood oxygen saturation (SpO2) throughout the session. The normal range is typically above 95%. Blood oxygen saturation <90% may be an indicator of clinical unwellness.
This is the average heart rate per minute during the session. Normal resting rates range between 60–100 bpm.
In Obstructive Sleep Apnea (OSA), the upper airway collapses during sleep. During these events, blood oxygen saturation drops from baseline. The oxygen drops, or ODI (oxygen desaturation index), is a measure of how many times the blood oxygen drops each hour of the night. Lower numbers (<5) generally indicate the normal range.
Use the “Sleep journal” section to log relevant events or behaviors.
Troubleshooting & Device Behavior
Here’s how to solve common issues like auto shut-off, missing reading and app connection problems.
- Please ensure that the battery has sufficient charge.
- If the issue is not related to low batteries, please contact us through our form with:
- A photo or short video showing how the ring is worn
- A screenshot of the data gap or missing records on the app
- The serial number of your O2 ring.
If the Bluetooth icon stays on, it means the ring is still trying to connect to the app. To let it power off automatically, please turn off your phone’s Bluetooth and fully close the myNarval. The ring will then shut down on its own after a short while.
The O2Ring uses a built-in rechargeable battery and doesn’t support manual battery replacement. If your device isn’t charging, try the following steps:
- Charge for at least 2–3 hours, even if there’s no charging icon or screen activity. Then check if the device works as expected.
- If the device still doesn’t respond, please contact us through our form with:
- A photo or short video showing how the ring is worn
- A screenshot of the data gap or missing records on the app
- The serial number of your O2 ring.
Products Specs & Safety
The O2 ring is made from medical-grade silicone that is both durable and comfortable for long-term wear. The material that directly touches your skin is silicone, which is hypoallergenic and gentle, ensuring it’s safe for most skin types.
Data management
To create a new password from the app, go to Settings, then select Manage Access & Password. From there, tap on Create New Password and follow the instructions to set up your new password.
If you’ve forgotten your password, don’t worry, you can easily create a new one directly from the login screen.
Open the app and tap on “Forgot Password?”. Enter the email address associated with your account and follow the instructions sent to your inbox. You’ll receive a secure link allowing you to reset your password. Simply create a new password, confirm it, and log in again.
If you don’t receive the email within a few minutes, please check your spam or junk folder.
You have the right to request a copy of the personal data we hold about you.
To request a data export:
- Send an email to privacy@resmed.eu
- Use the subject line: “myNarval – Data Access Request”
- In your email, please include:
- The email address associated with your myNarval account
- Your full name
- A brief description of your request (e.g. “I would like a copy of my personal data”)
We may need to verify your identity before processing your request. Once verified, we will provide your data in a commonly used electronic format, in line with applicable data protection laws.
We may need to verify your identity before processing your request. Once verified, we will provide your data in a commonly used electronic format, in line with applicable data protection laws.
You have the right to request deletion of your personal data, subject to legal and regulatory requirements.
To request data deletion:
- Send an email to privacy@resmed.eu
- Use the subject line: “myNarval – Data Deletion Request”
- In your email, please include:
- The email address associated with your myNarval account
- Your full name
- A clear statement that you are requesting deletion of your personal data
Please note:
- Deleting your data is permanent and cannot be undone
- Some data may need to be retained where required by law or regulatory obligations
We will confirm once your request has been processed.
If we collected and are processing your Personal Data with your consent, then you can withdraw your consent at any time. Withdrawing your consent will not affect the lawfulness of any processing we conducted prior to your withdrawal, nor will it affect processing of your Personal Data conducted in reliance on lawful processing grounds other than consent.
You can contact us any time to exercise any of the rights mentioned above at the following address: privacy@resmed.eu
Note: Withdrawing consent may limit your ability to use features of the app.
You have the right to opt-out of marketing communications we send you at any time. To unsubscribe from our emails, communications and newsletters, from your account settings, select your notification preferences or click the Unsubscribe link at the bottom of every newsletter or email we send you.
For Support
Please contact mynarval@resmed.com from your registered email address and include a brief description of your issue
myNarval is not a medical device.
PROMOTIONAL MATERIAL – Narval CC is compliant with applicable regulations. Manufacturer: Resmed.
Pulse Oxymeter O2 ring is a CE-marked medical device (CE NB0197). Manufacturer: Shenzhen Viatom Technology Co., Ltd.
Local contact: Resmed. Please refer to the instructions for use for relevant information related to any contraindications, warnings and precautions.
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