Researchers tested whether three different injectable substances could help braces move teeth faster in rats. They compared a steroid injection, vitamin D injection, and a natural body chemical called PGE2 against regular braces without injections. The steroid worked best for moving teeth quickly, but surprisingly, the PGE2 injection kept teeth from sliding back after treatment stopped. This animal study suggests that doctors might one day use these injections to make braces work faster and more effectively, though more research in humans is needed before this becomes standard practice.
The Quick Take
- What they studied: Whether injecting three different substances under the gums could help braces move teeth faster and prevent teeth from moving back after braces come off
- Who participated: 105 laboratory rats randomly divided into five equal groups of 21 rats each, with different treatment conditions
- Key finding: Steroid injections made teeth move fastest during treatment, while PGE2 injections prevented the most tooth movement after braces were removed (teeth stayed in place better)
- What it means for you: This animal research suggests that future orthodontic treatments might use special injections to speed up braces and keep teeth stable longer, but human studies are still needed to confirm safety and effectiveness
The Research Details
Scientists conducted a carefully controlled experiment using 105 rats divided randomly into five groups. One group received no braces or injections (negative control), another got braces without injections (positive control), and three groups got braces plus injections of either a steroid, vitamin D, or a natural body chemical called PGE2. The researchers measured how far the rats’ front teeth moved every week for 4 weeks while wearing braces. Then they stopped the braces for 2 weeks to see how much the teeth stayed in place, followed by 2 more weeks to measure if teeth moved backward. A second researcher who didn’t know which group was which checked the results to prevent bias. After the study ended, the researchers examined the bone and tissue around the teeth under a microscope to understand how the injections worked.
This research design is important because it tests three different substances in the same study, allowing direct comparison of which works best. Using animals first lets scientists test safety and effectiveness before trying these treatments in humans. The study also measured both how fast teeth move and how stable they stay afterward, which are both important for successful orthodontic treatment.
This is a well-designed animal study with good scientific controls. The researchers randomly assigned rats to groups and used a blinded reviewer to prevent bias in measurements. They used proper statistical tests to analyze the data and examined tissue samples under a microscope to confirm their findings. However, because this is an animal study, results may not directly apply to humans. The study was published in a peer-reviewed journal, meaning other experts reviewed it before publication.
What the Results Show
During the 4-week period when braces were actively moving teeth, the steroid injection group showed the fastest tooth movement, followed by the vitamin D group, then the PGE2 group. All three injection groups moved teeth faster than rats with braces but no injections. The differences were statistically significant, meaning they were unlikely to happen by chance. When the braces were removed and the researchers measured relapse (teeth moving backward), the PGE2 injection group showed the least amount of backward movement. This was surprising because PGE2 didn’t move teeth the fastest during treatment, but it did the best job keeping them in place afterward. The steroid group, which moved teeth fastest, had more relapse than the PGE2 group. Tissue samples examined under a microscope showed that the injections changed how bone and tissue responded around the teeth, explaining why movement and stability differed between groups.
The vitamin D injection group showed moderate results—faster tooth movement than controls but not as fast as steroids, and moderate relapse rates between the steroid and PGE2 groups. No harmful effects were observed in any of the injected groups, suggesting these substances were safe when injected under the gums. The histological (tissue) findings matched the tooth movement measurements, confirming that the injections were actually changing the biological response in the bone and tissue around teeth.
Previous research has shown that steroids can speed up tooth movement, and this study confirms that finding. However, this appears to be the first study directly comparing how much teeth move backward (relapse) after treatment with different accelerating agents. The finding that PGE2 provides better stability after treatment is novel and suggests that the best accelerating agent might not be the one that moves teeth fastest—stability after treatment is equally important.
This study used rats, not humans, so results may not directly apply to people. Rats’ bones and teeth respond differently than human bones and teeth. The study only lasted 8 weeks total (4 weeks of movement, 4 weeks of retention and relapse), while human orthodontic treatment takes much longer. The injections were given under the gums in rats, but it’s unclear if this same approach would work or be practical in humans. The study didn’t test different doses of these substances or long-term effects beyond 8 weeks. More research in humans is needed before these injections could be used in dental offices.
The Bottom Line
Based on this animal study, these injectable substances show promise for speeding up orthodontic treatment and improving tooth stability. However, human clinical trials are necessary before any of these treatments could be recommended for actual use. If you’re interested in faster orthodontic treatment, discuss current evidence-based options with your orthodontist rather than expecting these experimental treatments to be available soon. Confidence level: Low to moderate for future application (this is early-stage animal research).
Orthodontists and dental researchers should pay attention to these findings as they plan future human studies. People currently wearing braces should not expect these injections to be available yet. Patients interested in accelerated orthodontic treatment should ask their orthodontist about proven methods that are already available. This research is most relevant to dental professionals and researchers, not the general public at this time.
This is basic research using animals, so it will likely take 3-5 years of additional human studies before any of these treatments could potentially become available in dental offices. Even then, they would need approval from regulatory agencies and extensive testing for safety and effectiveness in humans.
Want to Apply This Research?
- If you’re currently in orthodontic treatment, track your tooth movement progress by taking photos of your smile from the same angle weekly and noting any changes in tooth position or bite alignment. This helps you see progress and discuss results with your orthodontist.
- Use the app to set reminders for consistent orthodontic care habits: wearing retainers as prescribed, maintaining excellent oral hygiene around braces, and attending all scheduled appointments. These proven methods are more important than waiting for experimental treatments.
- After braces are removed, use the app to track retainer wear compliance and monitor for any tooth movement over months and years. Set monthly reminders to check your bite and tooth position, and report any changes to your orthodontist immediately, as early intervention prevents major relapse.
This research was conducted in laboratory rats and has not been tested in humans. These injectable substances are not currently approved or available for orthodontic use in dental offices. Do not attempt to obtain or use these treatments based on this animal study. Anyone considering orthodontic treatment should consult with a licensed orthodontist about proven, evidence-based options. This summary is for educational purposes only and should not be considered medical advice. Always follow your orthodontist’s recommendations for tooth movement and retention.