Sore corners of the mouth are not only painful for your horse—they also call for a clear change in how you ride and which bit you use. Whether it's a bit sore our a wound that your horse got out in the field: most importantly, they require proper care and a horse-friendly transition period. In this post, we'll show you how to support your horse during this sensitive phase and which bits are most suitable for reintroducing bit use.
Healing Phase: Why the Bit Has to Go
If your horse has sore mouth corners, rest is key—not just in the stable but especially in the mouth. Superficial skin injuries at the corners of the mouth typically heal within about 14 days. During this time, a bit should be strictly avoided. Anything else could hinder healing and potentially lead to long-term issues. Bitless riding is a horse-friendly alternative during this initial phase. Hackamores, sidepulls, or other bitless bridles allow for continued, controlled riding without irritating the sensitive area.

Post-Acute Phase: Starting with a Soft, Flexible Mullen Mouth Bit
Once the initial two weeks have passed and no open wounds remain, you can cautiously reintroduce a gentle bit. A soft, flexible mullen mouth bit like the NATHE Mullen Mouth Bit has proven to be effective. Made from high-quality thermoplastic with an exceptionally smooth surface, it offers a large contact area and reduces unnecessary tension at the corners of the mouth thanks to its shape. Especially during recovery, the bit should be slightly thicker—particularly around the corners of the mouth. This helps distribute pressure more evenly and protects the delicate lip tissue. The NATHE bit scores points with its ergonomic design and comfortable feel.

Additional Support and Long-Term Healing
Products like mouth butter can provide extra healing support. They enhance the bit’s glide and have a soothing effect on already irritated skin. However, even if the area looks healed from the outside, the tissue is not yet ready for full use. A complete regeneration usually takes 6 to 8 months. During this time, patience and gentle handling are crucial—any unnecessary irritation could delay or even reverse healing progress.
Gradual Return to Jointed Bits
After 2 to 3 months of riding with a flexible mullen mouth bit, a careful transition to a jointed bit may be possible. This could be a single or double-jointed bit, depending on your horse’s preference and oral anatomy. Keep in mind: double-jointed bits exert more pressure toward the corners of the mouth and may not be ideal during the recovery phase. We recommend starting with a single-jointed bit and closely monitoring your horse’s response. If it's well tolerated, you can gradually build from there.

Gentle Alternatives and Secure Transitional Options
If you’re ready to return to a normal bit, eggbutt bits are a gentle choice. These are particularly mouth-corner friendly, as the sidepieces have a smooth transition and rest gently against the horse’s mouth. The fixed connection between the mouthpiece and sidepieces prevents pinching, making them especially suitable for sensitive horses. Eggbutt bits foster a stable, trusting connection between rider and horse—an ideal next step on the road back to a regular training routine.

Our Recommendation: Take Your Time Returning to Normal
Full healing takes time—usually about 6 to 8 months before the corners of the mouth can bear normal tension again. Like any other time, a gentle approach to bits, bridles, and rein aids is essential. Trust in proven products like the NATHE Mullen Mouth Bit made of Thermoplastic and protect your horse’s oral health for the long term. Be diligent in checking the mouth corners and choose bits carefully—better too soft than too demanding. After all, the goal is not just a functioning riding horse but a healthy, content one.
Conclusion: The Right Bit Gets You Safely Through Recovery
Sore mouth corners aren’t a reason to panic—but they are a clear sign that change is needed. With a bit of patience, solid knowledge, and high-quality products, you can provide your horse with the best possible care. The goal is clear: a healthy, happy horse with permanently protected mouth corners. You should also take a closer look at your current bit, as unsuitable bits can, in the worst case, cause injuries to the corner of the mouth. We explain how to find the right bit for your four-legged friend in the article: 'How do I find the right bit?'