Digital dental scans have made ordering a custom night guard faster and easier than ever. If you already have a digital scan on file, you might be wondering:
Can I reuse my old digital scan for a new night guard—or do I need a new one?
The short answer is: sometimes. It depends on how current your scan is and whether your teeth have changed since it was taken. Below, we’ll explain exactly when an old scan can be reused—and when it’s best to update it.
This article is part of our in-depth guide to using digital dental scans (.STL files) to order custom night guards with confidence.
What Is a Digital Dental Scan?
A digital dental scan (often saved as an .STL file) is a 3D model of your teeth created using an intraoral scanner. These scans are commonly taken at dental offices and are used to fabricate custom dental appliances like:
Because they’re digital, scans don’t degrade over time the way physical impressions can—but your teeth can change.
When You Can Reuse an Old Digital Scan
You may be able to reuse an existing digital scan if all of the following apply:
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✅ The scan accurately reflects your current dental anatomy
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✅ You have not had dental work since the scan was taken
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✅ Your teeth have not shifted, chipped, or worn down significantly
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✅ All molars and biting surfaces were fully captured
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✅ The original file is a true .STL file (not a screenshot or PDF)
If your scan meets these criteria, it can often be reused to create a new night guard—saving time and avoiding the need for a new impression.
When You Should Not Reuse an Old Scan
In many cases, a new scan or impression is the safer choice. You’ll want an updated scan if you’ve had:
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❌ Crowns, fillings, veneers, or implants
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❌ Orthodontic treatment (braces or aligners)
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❌ Tooth extractions or major dental repairs
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❌ Noticeable shifting or changes in your bite
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❌ Increased grinding that’s altered tooth shape
Even small changes can affect the fit, comfort, and effectiveness of a night guard. A scan that no longer matches your teeth can lead to a guard that feels tight, loose, or uncomfortable.
Why Scan Accuracy Matters for Night Guards
Night guards are precision appliances. They rely on an exact fit to:
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Stay securely in place overnight
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Distribute grinding forces evenly
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Prevent jaw strain and tooth damage
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Feel comfortable enough to wear consistently
Using an outdated scan increases the risk of fit issues—which can mean remakes, adjustments, or discomfort.
How Old Is Too Old?
There’s no universal expiration date for digital scans. Some scans taken a few years ago may still be usable—if your teeth haven’t changed.
That said, many dental professionals recommend using scans taken within the last two years, especially for night guards where bite accuracy is critical.
Not Sure If Your Scan Is Still Usable?
That’s completely normal.
Because only you or your dental provider can confirm whether your teeth have changed since the scan was taken, we’re unable to determine this for you. If you’ve had any dental work or changes to your bite since the scan was created, an updated scan or impression will be needed.
👉 When in doubt, it’s always best to use a scan that reflects your current dental anatomy to ensure proper fit and comfort.
Frequently Asked Questions
Can I reuse a digital dental scan for a new night guard?
A digital dental scan can be reused, but only if it still accurately represents your current teeth. If you have not had any dental work or noticeable changes since the scan was taken, it may be suitable for fabrication.
How long does a digital dental scan stay accurate?
A digital scan does not expire on its own. Its accuracy depends on whether your teeth have changed since the scan was created. Even small dental changes can affect the fit of a night guard.
Can a company tell if my old digital scan is still usable?
No. A company cannot determine whether an older scan is still accurate, since only you or your dental provider can confirm whether your teeth have changed since the scan was taken.
What dental changes require a new digital scan?
A new scan or impression is recommended if you’ve had crowns, fillings, veneers, implants, orthodontic treatment, tooth extractions, or noticeable changes to your bite since your original scan.
Is it safer to use a new scan when ordering a night guard?
Yes. Using a scan that reflects your current dental anatomy helps ensure proper fit, comfort, and protection. When in doubt, an updated scan is the safest option.
What if I’m unsure whether my teeth have changed?
If you’re unsure, it’s best to use a new scan or impression. Accuracy is key when fabricating a custom night guard, and updated records help reduce the risk of fit issues.
The Bottom Line
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✔️ Digital scans can often be reused
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✔️ Accuracy matters more than age
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❌ Any dental changes = time for an updated scan
Our goal is always the same: a night guard that fits beautifully and protects your smile properly.
If you have questions about your scan, we’re just a message away 💚