Although some teeth are in obvious need of extraction, like the above abscess, the decision process for extraction can range from simple to complicated and is based on several factors:
(1) the condition of the tooth
(2) the condition of the patient
(3) the cooperation or decision of the owner
Condition of Tooth
A thorough evaluation of the involved tooth or teeth is the first step, to determine the feasibility of salvaging the tooth as compared to the benefits if extracted. While some teeth can undergo extensive therapy to salvage them, sometimes the option to extract is the best choice for a combination of the above reasons.
Condition of Patient
Full evaluation of the patient is necessary as well. In a patient with any systemic compromises (e.g., endocarditis, organ disease, implants), extraction may allow a potential future source of infection to be removed. Those that should have anesthetic events and times minimized might also benefit from extraction. In addition, the age of the pet should be considered. A young pet may be spared a lifetime of troubles if a compromised tooth is removed preventively. Conversely, a compromised but stable tooth in a senior may never move on to cause significant disease.
Cooperation of Owner
Owner consent and commitment is also necessary. In lieu of extraction, extensive periodontal or endodontic therapy may be necessary to preserve a tooth, so the additional costs, anesthetic events, and even the ability to provide home care should be considered. For whatever reason, and no matter how much it might be indicated, an extraction should never be performed without the owner’s knowledge and consent. A signed release form with “permission to extract” may be adequate if minor, simple extractions are anticipated. Any time a more complicated, unexpected extraction is warranted (e.g., a canine or carnassial tooth, multiple teeth) it is best to contact the owner for complete disclosure and permission. When owners admit their pet, they should be informed that unexpected lesions may be found during the dental procedure and it is important that they provide a means of contact.
Which Teeth need to go?
Strategic vs. Non-strategic Teeth
Is the tooth important? Canine teeth and carnassial teeth are often worth taking extra steps to save. Smaller, less important teeth may be extracted without significant impact – though some owners think all teeth are important.
• Smaller, non-strategic teeth adjacent to strategic teeth may be “sacrificed” in order to be able to more fully treat the larger tooth:
• Lower first incisors adjacent to canines
• Teeth adjacent to lower 1st molars (4th premolar, 2nd molar)
Extent or Stage of Periodontal Disease:
Full evaluation with probing, radiographs and physical exam will indicate the extent of disease and potential compromise to the tooth.
Strategic vs. Non-strategic Extraction:
Extraction of adjacent non-strategic teeth will often allow better access to the periodontal structures of the strategic teeth, as well as the ability to provide advanced therapy (root planing, etc).
When teeth are so close together that the gingival tissue is not able to surround a tooth completely, a significant risk for developing periodontal disease exists. Food and bacteria are not prevented from entering the periodontal space and are very difficult to remove by brushing or normal chewing behaviour. Common teeth affected by crowding are the 6’s with 7’s and 8’s. This is particularly true for brachiocephalic breeds.
While any level of mobility does not automatically make a tooth a candidate for extraction, extensive mobility that does not respond to therapy may be an indication of insufficient attachment.
Furcation exposure is not an automatic reason for extraction, either. In fact, with good home care, these teeth can often be salvaged, as long as they are not accompanied by additional attachment loss (deep pockets).
ANY time a pulp’s vitality is compromised, extraction or endodontic therapy should be performed; persistence of a non-vital pulp will cause bacteria to flow into systemic circulation on a regular basis (at the apical infection site).
• Open canal? If so, the tooth is compromised
• Pulp not exposed? Bacterial translocation can occur over the long term so even “chipped” teeth are
vulnerable to future abcessation.
Vital tooth will transmit light well – often pink of the pulp is visible
Non-vital tooth will appear dark and discolored, sometimes with a “black” pulp appearance
Compare with similar teeth if unsure
Confirm results with radiology
• Intraoral radiology:
Look for any periapical bone loss (not “diagnostic” for abscessation, a histopathologic diagnosis, but highly indicative)
Evaluate canal width as compared to similar teeth (non-vital tooth will not produce further dentin, so canal may appear wider)
Evaluate condition of roots - presence of resorptive lesion or fracture may lead to extraction
Extraction vs. Endodontic Therapy:
• Is the tooth an appropriate candidate for endodontic therapy?
• Radiograph roots to see if solid
• Fully evaluate canine teeth in cats - often have root resorption after crown fracture
• Additional cost for endodontics - check commitment of owner
• Additional anesthetic time involved - evaluate health of pet
• Repeat occurrence? Most fractured teeth are as a result of behavioural patterns. Will chewing on hard objects continue? Will there be an increased risk of automobile accidents? Jumping? Fighting?
Retained deciduous tooth with presence of permanent counterpart or it’s eruption:
• Any time there are two teeth in the same place at the same time, the deciduous tooth needs to be
• Persistence of the deciduous tooth will cause the permanent tooth to erupt in an abnormal position:
• Most permanent teeth will erupt further lingual or palatal to their normal position - base narrow
mandibular canines often require intervention
• Maxillary canine teeth will erupt further forward (rostral or mesial) to their normal position - this can close
the natural diastema for the mandibular canine
Fractures of deciduous teeth:
• An open pulp can lead to infection spreading to the apex of the tooth. This can damage the underlying
permanent tooth bud
Non-vital deciduous teeth:
• Similar to a fracture, a non-vital tooth can become infected. Infection at the apex can damage the
underlying permanent tooth bud
Deciduous malocclusion causing mechanical interference to continued jaw growth:
• Even if a “temporary” situation (i.e., adult jaw will eventually be a normal length), these teeth can disrupt normal jaw growth
• Growth of jaws is disproportionate prior to 12 weeks of age in dogs. Window for interceptive extractions very short to correct malocclusions.
If there is discomfort or pain from a maloccluded tooth (e.g., base narrow mandibular canine hitting the palate), then extraction (or crown reduction with pulp capping) will provide a more comfortable bite.
If a tooth is “missing”, it should always be radiographed. With few exceptions, an unerupted tooth should be extracted, because it could form a large dentigerous cyst that can destroy bone.
If the extra tooth will cause crowding or contribute to periodontal disease, it should be extracted. Be sure to radiograph to find all supernumerary teeth.
With resorptive (odontoclastic) lesions, full evaluation of the tooth with radiography is necessary to determine the extent of root involvement. In cats, this is always an indication for extraction due to the pain involved. Canine resorbtion is often less painful and extraction is limited to those with significant gingival hyperemia or evident discomfort.