Dental Corner: How to detect and treat feline odontoclastic resorptive lesions - Veterinary Medicine
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Dental Corner: How to detect and treat feline odontoclastic resorptive lesions


Clinical lesions and radiographic evidence of root resorption and ankylosis

Figures 5A & 5B. The maxillary right third premolar (#107) shows evidence of an FORL on oral examination (5A). The dental radiograph (5B) shows #107 (white arrow) with extensive root resorption. This tooth is a good candidate for crown amputation. 5C. The tooth in Figures 5A & 5B before crown amputation. A mucogingival flap has been raised exposing the buccal cortical bone (1) overlying the resorbing roots. The crown (2) will be amputated along the black dotted line, intentionally leaving what’s left of the roots behind. The flap is then reapposed with fine, absorbable suture.
A crown amputation procedure has been described to extract certain teeth exhibiting FORLs.6 In this procedure, you remove the crown of the tooth affected with an FORL while intentionally leaving the resorbing roots behind. Before performing this procedure, make sure there is no evidence of concurrent periodontal disease. Cats with associated periodontitis or stomatitis are not candidates for crown amputation. Dental radiography is essential for accurate diagnosis and treatment planning (Figures 5A-5C).

In multirooted teeth, if only one root is affected with resorption, the root exhibiting the resorption should be crown-amputated, and the healthy root should be elevated and routinely extracted.


If you perform dental extraction or crown amputation, manage the patient's pain with a combination of preoperative and postoperative analgesia, intraoral regional nerve blocks, and analgesics for a few days after the procedure. A common protocol would include premedication with hydromorphone, appropriate intraoral regional nerve blocks with bupivacaine hydrochloride, postoperative hydromorphone, and a fentanyl patch. Of course, many other options are available, and the individual pain management plan should be based on the expected degree of pain and the patient's general health status.

Postoperative antibiotics are often given prophylactically for five to seven days. Antibiotics effective against gram-negative anaerobic bacteria are good choices. Other postoperative oral hygiene measures such as oral rinsing with chlorhexidine can be used, but they are often poorly tolerated by cats.

Reevaluate patients two or three weeks after the procedure to verify that healing has occurred. At that time, a dental home care program can be reinstituted. This may include a combination of tooth brushing, dental diets, appropriate chew treats, and a scheduled six-month recheck. Keep in mind that although a home care program is an important tool in preventing periodontal disease and other oral problems, nothing can be done at home to prevent FORLs. This fact has assuaged many clients' guilt.


1. Gorrel C, Larsson A. Feline odontoclastic resorptive lesions: Unveiling the early lesion. J Small Anim Pract 2002;43:482-488.

2. Harvey CE, Orsini P, McLahan C, et al. Mapping of the radiographic central point of feline dental resorptive lesions. J Vet Dent 2004;21:15-21.

3. Gorrell C. A practical approach to managing feline odontoclastic resorptive lesions, in Proceedings. 18th Annu Vet Dent Forum 2004.

4. Bellows J. Oral surgical equipment, materials, and techniques. In: Small animal dental equipment, materials and techniques—A primer. Ames, Iowa: Blackwell Publishing, 2004;297-328.

5. Holmstrom SE, Frost P, Eisner ER. Exodontics. In: Veterinary dental techniques for the small animal practitioner. 2nd ed. Philadelphia, Pa: WB Saunders Co, 1998;216-244.

6. DuPont G. Crown amputation and intentional root retention for advanced feline resorptive lesions—A clinical study. J Vet Dent 1995;12:9-13.

"Dental Corner" was contributed by Daniel T. Carmichael, DVM, DAVDC, The Center For Specialized Veterinary Care, 609-5 Cantiague Rock Road, Westbury, NY 11590.


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