Teeth are extracted for a number of reasons in our canine and feline patients. One of the most common reasons to perform extractions is advanced periodontal disease. Multiple studies have shown that periodontal disease has a prevalence of 80-85% in dogs and cats over 2 years of age.1,2 Early or mild periodontal disease does not always necessitate extraction of the affected teeth, but advanced or end-stage periodontal disease often requires extraction for treatment.1,3
Persistent deciduous teeth are found frequently in toy/small breed dogs and should be addressed when the dogs are still young. Left in place, the continued presence of deciduous teeth can cause irreversible periodontal disease of the adjacent permanent tooth. Deciduous teeth should exfoliate once the permanent successive tooth has fully erupted; if they are still present, they should be removed.1 Often timing of removal coincides with spay/neuter surgery as most of the adult dentition should erupt by the age of 5-7 months.1,3
Fractured teeth are seen with an incidence of nearly 25% in our canine patients.2 Unfortunately, many of these fractures are caused by inappropriate chew items such as nylabones, antlers, and marrow bones.4 Root canal treatment is an option for complicated crown fractures while extractions are often required for complicated crown root fractures or long-standing complicated crown fractures.4,5
Malocclusion is another frequent finding in our toy/small breed and some purebred dogs. While orthodontic appliances can resolve the issue, selective extraction can also be successful. The goal is to provide a pain-free functional occlusion.1 Crowding/supernumary teeth can also be treated with selective extraction. This gives the remaining teeth room for a healthy periodontium.
Any “missing” teeth should be investigated in dogs and cats. A great time to investigate is during a spay/neuter as the adult dentition should be erupted or in the process of erupting by 5-7 months.1 Any unerupted or impacted teeth can be treated at that time. Bony impaction will require extraction while soft tissue impaction can be treated with an operculectomy to allow the tooth to continue its normal eruption.1 Addressing these teeth at a younger age can prevent the development of dentigerous cysts, which can cause significant bone loss, damage to nearby structures, and potential jaw fractures.1
Cats (and some dogs) often present with tooth resorption. Unfortunately, there is no way to stop or reverse the tooth resorption process. Tooth resorption in cats can be classified as Type 1, 2, or 3.6 Type 1 tooth resorption in cats requires extraction of all remaining tooth structures while type 2 tooth resorption in cats can be treated with crown amputation. Type 3 tooth resorption occurs when one tooth is affected by both types 1 and 2 tooth resorption, necessitating different approaches to different regions of the tooth. Intraoral radiographs must be obtained prior to treatment to determine the type and extent (or stage) of tooth resorption.6 Dogs can also present with tooth resorption, but theirs is not classified as type 1, 2, and 3. The most common type of tooth resorption seen in dogs is external replacement resorption which resembles Type 2 tooth resorption in cats.7,8,9 This type does not always require treatment unless it involves the crown or has severely damaged the integrity of the tooth.7,8,9 Like type 2 in cats, this type of tooth resorption may be treated with crown amputation when indicated.7,8,9 The second most common type of resorption found in dogs is external inflammatory resorption, often seen in relation to tooth root abscesses due to endodontic disease and/or advanced periodontal disease.7,8,9 These teeth require extraction due to the periapical lucencies indicative of endodontic disease.7,8
Feline chronic gingivostomatitis is an uncommon but debilitating disease affecting our feline patients. Total or caudal mouth extraction procedures do not always provide an immediate cure, but they are recommended as the best chance for a cure.10 The majority of cats do improve with about 30% having refractory disease and requiring medication for a period of time.10,11 Studies have found cyclosporine to be a good adjunct treatment after caudal/partial/total mouth extractions are performed.10
Prior to performing extractions, be sure to get permission from the client. Estimates should be provided with a range that allows for multiple extractions. Often the extent of treatment needed cannot be appreciated until an examination, charting, and intraoral radiographs are performed under general anesthesia. Have a plan in place after obtaining all the pertinent information. Does the owner need to be called and informed of all the findings or only unexpected findings? What if the owner can’t be reached? Would the owner prefer you to extract all the necessary teeth or just perform a complete dental prophylaxis and return another day for extractions? Some owners become very upset if teeth are extracted without permission. This is often due to a lack of understanding about the disease process…or cost. What happens if the required work will go over the high end of your estimate?
Local anesthetic blocks are an important part of dentistry and oral surgery; they help prevent wind-up, decrease anesthetic requirements, and provide post-operative pain control.1,3 Lidocaine and Bupivacaine are common local anesthetics used in our canine and feline patients. These can be purchased as formulations with vasoconstrictors or they can be mixed with opioids.1,3 Do not exceed 4 mg/kg of Lidocaine or 2 mg/kg of Bupivacaine for dogs and cats.3 The volume of local anesthetic also needs to be taken into consideration.12,13 Larger volumes can be given per site in larger dogs and cats (see charts in the slides that follow).12,13 Commonly performed local anesthetic blocks include the infraoribital, caudal maxillary, rostral mandibular (mental), and caudal mandibular (inferior alveolar).1,3 Specific landmarks and guidelines will be discussed during the presentation.
Equipping the dental operatory with proper equipment and instruments is imperative for success. Recommended supplies include: high-speed delivery unit with integrated water coolant, burs for high-speed handpiece (1/2, 1, 2, 4, 700, 701,701L, cylindrical diamond, conical white stone), scalpel blades (#11, #15, #15C), periosteal elevators (molt #2, molt #4, freer), dental elevators (winged elevators #1-4), luxators in various sizes, extraction forceps, small alveolar curette, tissue forceps: Brown-Adson 7X7 tooth, Olsen-Hegar needle holders, scissors (Dean), root tip picks, dental radiographs (mandatory), excellent lighting, suture (Monocryl in 3-0 to 5-0 sizes, with reverse cutting or tapered needles), Gel-foam of Vetspon for hemostasis.1,3
Dental extractions can be divided into two major categories: “simple/closed” versus “surgical” extractions.1,3 Simple extractions do not require removal of alveolar bone or sectioning of multirooted teeth, while surgical extractions do. Mucoperiosteal flaps are created for surgical extractions, and they should be closed without tension.1,3 Absorbable sutures are recommended for extraction site closure, using a simple interrupted suture pattern.1,3
Extraction complications can occur for a number of reasons; the best approach for handling complications is prevention.1,3 Preventive measures include pre-operative intraoral radiographs, proper technique, good lighting, +/- magnification, post-operative radiographs, and occasional intraoperative radiographs.14,15 Proper technique includes using the correct instruments as intended and technique improves with appropriate training.14,15,16 Common complications include retained tooth roots, pushing tooth roots in to the nasal cavity/mandibular canal, orbital penetration, hemorrhage, and dehiscence.14,15 Each of these complications will be discussed in today’s presentation in addition to their prevention and treatment. Remember to ask for help, be honest, and learn from your mistakes.