Q. My lower-level dressage horse has a bad habit of grinding his teeth on the bit and making a noise. Judges have marked us down for this as being “tense.” My horse doesn’t seem tense to me and he does it all the time when I ride. Is there any way I can get him to stop?

Gerhard Politz

A. In dressage, we use the word “tension” to indicate a lack of relaxation and submission. Tension is not always manifested in obvious behavior problems such as spooking, bolting or coming above the bit. Sometimes it appears much more subtly. Particularly in stoic horses, teeth grinding or tail swishing may be the only perceptible response to an underlying physical discomfort. Unfortunately, if the discomfort is not addressed promptly, this response may turn into a habit, which can be difficult to eliminate. So the sooner you can identify the cause, the better.

Start your investigation in the most obvious place: your horse’s mouth. Ask a qualified equine dentist to perform a thorough mouth examination and teeth floating. (If your veterinarian has floated his teeth recently and noted no problems, it may still be worth getting a second opinion from a dental specialist.)

Next, enlist the help of an experienced rider or tack expert to evaluate the suitability and fit of your bit and noseband. To achieve proper acceptance of the bit, your horse must feel comfortable with the bit and free to move his jaw in a soft chewing motion. As this motion naturally generates a fair amount of saliva, visibly dry lips and mouth during your training session are also signs of bit/contact problems.

A too-thin bit or a bit adjusted too high in his mouth may discourage this chewing motion. Try lowering the bit a hole or two and experiment with different shapes and thicknesses of bits, as well as different types and combinations of metals, such as copper or sweet iron.

Also be sure your noseband isn’t so tight that it restricts jaw mobility. This is a common problem with flash and “crank” nosebands (the latter are aptly named and, unfortunately, often very detrimental to a horse’s proper acceptance of the bit). If you use one of these nosebands, consider switching to a dropped noseband, adjusted correctly along your horse’s chin groove. To be sure your noseband is adjusted loosely enough, you must be able to fit two or three fingers between the noseband and the nasal bone. Another simple method is to offer your horse a piece of carrot or apple when he’s bridled. If he can’t munch it easily, the noseband is too tight.

Find an expert to evaluate your saddle fit as well. It may be pinching your horse’s withers or pressing against his shoulder blades, which many horses find disconcerting, especially while trotting.

Ask your veterinarian to help rule out any other possible physical issues: sore back or hocks, sensitive soles, chiropractic problems (e.g., hips out of alignment), etc. What may not make your horse necessarily lame might be causing enough discomfort to manifest itself in teeth grinding.

At the same time, work with a qualified instructor to identify any rider errors that may be causing or contributing to the problem, especially in the way you use the contact to the bit. Rigid, bouncy or unsteady hands can cause a horse to go into “protective” mode. He may still perform all the movements asked of him but with a dry, immobile mouth and an inharmonious connection. I teach my students to influence their horses’ mouths in such a way that they are happy with the bit. With the correct, quiet elasticity and mobility in the connection, your hands create a conversation with your horse’s mouth. This skill takes years to master, but it should be made a top priority from the very beginning.

Finally, once you’ve investigated all of the above potential problems, consider your horse’s individual temperament. Perhaps he’s an overachiever who constantly tries to go more forward and do more work. With this type of horse, emphasize relaxation exercises, such as “chewing the reins out of the hands” and “releasing the reins with one or both hands.” Also encourage correct chewing motion by feeding him a sugar cube or two just before you mount. To break a long-standing teeth-grinding habit, it may even help to offer additional sugar cubes periodically during your ride.

Once you resolve the underlying cause–or combination of causes–of your horse’s tension, you will find that he not only stops grinding his teeth but also offers a happier connection and freer, more expressive movement throughout all of his work.

The career of Grand Prix dressage rider Gerhard Politz spans three countries and more than five decades. Before leaving his native Germany, he earned the professional Reitlehrer FN degree and the German Gold Medal for FEI wins while guiding several students to state and national championships. In England, he received certification as a British Horse Society Instructor. Since moving his program to Flintridge Riding Club in southern California in 1987, Gerhard has helped shape both the US Dressage Federation Instructor Certification Program and the design of the USDF dressage tests. His dedication to classical dressage principles and the training pyramid has benefited countless riders across the country, including many North American Junior and Young Rider Championships individual and team medalists.

This article was originally published in the January 2010 issue of Practical Horseman. Read more from Gerhard Politz in “Here’s How” in the May 2011 issue.