Chameleons have true teeth which we refer to as the “dental arcade”. The dental arcade is often broken in places due to physical trauma and bacterial infections which rot out the bone. The most commonly seen broken jaw is the physical trauma from rubbing their noses on their enclosures. The chameleon will rub it raw and straight through the bone. This is often seen on imported wild chameleons that are improperly kept and have no concept of a cage. The chameleon will continually try to press through the walls or lid even to self-injury. Luckily, better packing and keeping methods have decreased the occurrence of this injury.
Bacterial infection (see Stomatitis – Mouth Rot) can also occur where an injury occurs in the mouth and bacteria take hold. The bacteria will eat through bone which weakens the dental arcade to the point where it will break under normal usage.
A broken jaw is a downward spiral of problems as the immune system is stressed to the maximum trying to fight the infection which is either present or is attempting to take hold. And, at the same time, food intake has slowed due to the pain of chewing.
A broken jaw is relatively easy to diagnose as it is a literal break. Though it may take careful study to notice it being that a chameleon will not volunteer to open his mouth unless you can inspire him to try and scare you away. This is the perennial problem with bacterial infections – they happen hidden away. The main challenge of broken jaws is not identifying the break, but identifying it before the break occurs. If the break is imminent due to infection then you will notice puss or a green cheesy substance in the mouth. But you have to think to look in the mouth and this is why many of these cases advance so far before being treated. It is always a good idea to sneak a peak in your chameleon’s mouth when he eats to se if there is anything that should be caught early.
A jaw break due to nose rub is, unfortunately, easy to see as it is a literal removal of all layers of skin and you see raw bone. This is an extreme case of nose rub. Usually they do not rub that far, but even just a weakening of the point where the dental arcade meets in front can be enough for it to break during eating.
This female Trioceros quadricornis (Four-horned chameleon) has rubbed her snout to the point of breaking her dental arcade. This picture was taken mouths into recovery. The gray area around the front of her mouth is the scar issue. Although she did break the front of her jaw she was able to eat regularly with the back portion.
Prowlpuss was a male Trioceros quadricornis (Four-horned Chameleon) who came to me with multiple issues. A respectable number of issues came from a raging mouth infection that mutilated his mouth and teeth. You can see where the teeth should be. These were lost to the bacterial infection. This chameleon went on to live years after this image was taken which goes to show you how strong chameleons really are!
A broken jaw, or infection around the dental arcade, is definitely a veterinarian visit. Depending on how bad the situation is there may need to be a cleaning of the area to remove active infection. Saving the dental arcade gets hard and harder the longer the infection runs unchecked. There may be some surgery required. There is a very good chance that you will need to give antibiotic treatment.
Antibiotics are usually given in oral or injectable forms. Usually, veterinarians just prescribe a “broad spectrum” antibiotic that has a history of being effective with the most common bacterial strains. It is critical to follow through the entire antibiotic course even if improvement has been shown in order to reduce the chances of producing antibiotic resistant bacteria.