Dentistry at Nora Veterinary Hospital

posted: by: Dr. Jaclyn Martin Tags: "Clinic Specials" "News" 

Our clinic cat, iKat, had his annual exam a couple weeks ago. We found significant tartar, what we lovingly call teeth barnacles, and determined that he needed a full exam, cleaning and treatment under anesthesia. At the time of his exam, we drew blood to screen him for kidney and liver dysfunction, and to check his blood counts (red blood cells to make sure not anemic, white blood cells to fight infection, platelets to form blood clots appropriately). All of this was normal, so we scheduled him to have his procedure yesterday.
The night before, we brought him from his usual home in the kennel area upstairs to our treatment room cages, and made sure he wasn't fed overnight. In the morning, we did a quick exam to make sure nothing had changed drastically in his weight and heart function, then gave him a long-acting pain relief injection. Once that had been on board for an hour or two, we gave him an intramuscular injection of two other sedatives/anesthetics to allow us to get him on gas anesthesia.
We documented the procedure from this point on with photographs so you can see all the steps we take to monitor and support our patients, as well as the basic steps of a general dental exam and cleaning. Hope this helps to explain some of what goes on "in the back" when we are doing dental work, and helps alleviate the fear associated with your pets having anesthesia here!

1. This is our basic anesthetic/surgery report form. It includes all drug dosages and the route they are given by. The boxes at the bottom are where we record vital signs throughout the procedure. These are recorded at least every 10 minutes, usually every five, by an assistant who is in the area during the whole procedure to help the technician or doctor as needed. This is a permanent, official part of the medical record once it is filled out.

2. This is the dental chart for a cat mouth. Each tooth is represented on the illustrations, and we mark missing teeth, fractures, bone loss, and pockets in the gingiva as needed for each tooth. We also mark teeth that are extracted, and we keep it in the medical record to refer to during future exams and dental procedures.
3. This is our ChillBuster warming blanket. It is a very safe, very effective way to keep our patients warm without risk of thermal burns. This blanket is waterproof. It lies directly on the surgery table or the dental sink grate. We cover it with a clean towel for each patient, and can use that towel to cover the patient as well. iKat was under anesthesia for a little over an hour, with a lot of cold water being sprayed in his mouth (see below for description of the procedure) and his temperature was a normal 100.8 when he was waking up. Maintaining body temperature helps animals recover better, and makes the whole process less physically stressful on their bodies.
4. Once he was fully sedated, we placed an endotracheal breathing tube. This is connected to our anesthesia machine, and delivers oxygen and isoflurane gas directly to the lungs. The tube serves a couple very important functions, which is why we use it in nearly all procedures, even if injectable medication is enough to keep the animal sedated. First, it allows us to ventilate the patient if he is not breathing well on his own. Secondly, and most important during dentistry especially, it seals the airway, keeping the water, blood and saliva from the procedure from getting into the patient's lungs, which can cause aspiration pneumonia.
5. All anesthetized patients have an intravenous catheter in place throughout the procedure. This again serves multiple functions. First, it lets us give IV fluids to support blood pressure and hydration during anesthesia, since anesthetics can cause hypotension. Secondly, it is a route for us to give emergency drugs if we have an adverse event during anesthesia and have to do CPR. For dogs, it also is the route through which we give our induction drugs prior to intubation. And we sometimes use this catheter during recovery to give additional pain medication or sedatives if needed for animals that wake up extremely agitated or painful.
6. Our IV fluid pump allows us to give a precise amount of fluids at a steady rate. The fluid rate is calculated for each animal based on body weight and underlying conditions. For example, an animal with heart disease would have a lower fluid rate, and an animal with kidney disease would have a higher one, and probably get additional fluids after the procedure as well.
7. iKat is connected to EKG leads that help us monitor the electrical activity of his heart. This machine is more accurate in larger animals (it sometimes has difficulty reading the lower amount of electricity generated by a cat), but still is a useful monitoring tool for all of our patients.
8. The readout from our EKG machine. It has alarms that sound when the heart rate is too high or too low, or when the rhythm is abnormal.
9. Another way of monitoring the heart, this is an esophageal stethoscope. The stethoscope tubing is attached to additional tubing, rather than the standard bell at the end. This extra tube is fed down through the esophagus to the level of the heart, so that we can hear the heart very easily, even in very fat animals. This helps us to verify that the EKG readings are accurate. The technician (during cleanings) or the doctor (during surgical extractions) is listening to this heartbeat the whole time they are working in the mouth, so we are aware immediately of any changes in heart rate or rhythm.
10. iKat having radiographs (x-rays) taken prior to his cleaning. We use small towels to position the head at the proper angle for x-rays, and to support the head and neck during cleaning and extractions.
11. A radiograph of the right upper canine tooth and premolars. I know the image is blurry (screen photo rather than an import of the image file itself), but you can still appreciate how much of the tooth structure is below the bone and gingiva. Black is air, gray/fine white lines is the bone, and bright white is the teeth, with a darker line in the center that is the pulp canal.
12. Full mouth radiographic study, standard on all of our dentistries. We take additional shots as needed after extractions to verify that roots have been fully removed.

13. Cleaning the teeth with the piezo handpiece. This is instrument has a rapidly vibrating tip that removes tartar and staining. It is cooled by a steady stream of water so that it doesn't cause overheating in the sensitive nerve structures of the teeth and bone. We clean the crowns of the teeth as well as the upper part of the root that is below the gingiva but not encased in bone. In addition, we probe around each tooth to measure the depth of pockets around the roots. After cleaning, we polish the teeth with a mildly abrasive paste like our dentists use, to smooth out any rough or scratched areas that the metal instruments may have caused, since those grooves are good places for bacteria to accumulate and start forming plaque and tartar.
14. A closer look at the scaler handpiece. Notice that we wear gloves when working in the mouth. Even when there isn't periodontal disease, we are stirring up a lot of bacteria. We also wear face masks and eye protection so we don't breathe in any of the debris or get it in our eyes.
15. iKat resting in his recovery cage in the treatment area, where we can keep an eye on him. We leave the endotracheal tube in until our patient can swallow well enough to protect his airways from aspiration. We leave IV catheters until they are sitting up and moving around normally, in case they need additional medications. Nearly all patients go home the same day, although some cats do stay for a second pain injection the next day. Patients can eat small amounts the night they go home; we recommend softening the food for the first few days as the gums can be very tender, even when we have not extracted any teeth.

iKat did need some teeth extracted. We did not photograph this because it is hard to get close enough for good detail, and we didn't want to gross anyone out. There are probably YouTube videos, or pictures on websites of veterinary dental specialists like Brett Beckman or Jan Bellows if you are really curious, but I can describe some of the process here.

First, I inject a local anesthetic, bupivicaine, to numb the nerves of the affected jaw. Then I cut into the gingiva to allow it to be moved out of the way so that the bone over the tooth roots is exposed. I remove bone using the water-cooled high-speed drill on the dental machine to expose the roots, cut the tooth into single-root segments (many teeth have 2 or 3 roots that have to be separated before removal), remove these, smooth out the bone, and suture the gingiva back in place. The bone will fill back in over time, and often when we take x-rays at next year's cleaning, we find the bone level is consistent across the extraction site. Patients go home after extractions with pain medications and, if there is a lot of infection, antibiotics. Sutures dissolve over a few weeks, and most patients are feeling better than before the procedure within a few days, as periodontal disease and broken teeth are very painful conditions.