Page 140 - Manual of Equine Field Surgery

136 HEAD AND NEC.K SURGERIES ---------,,-

resulting from fistula formation, incomplete tooth

removal, bone sequestrum, infected tooth root ALTERNATIVE PROCEDURES

socket, packing breakdown, mucous membrane

healing prior to wound granulation, or the pres- Several options exist for treatment of periapical

ence of a foreign body i11 the wound. Long-term infections in horses. Medical therapy is limited to

complications can be associated with an incorrect the systemic administration of antibiotics and is

initial diagnosis resulting in persistence of the often ineffective. Ideally, the antibiotic therapy is

primary problem, removal of the wrong tooth, or guided by bacterial culture and sensitivity results.

leaving behind a diseased tooth or tumor. In the absence of bacterial culture results, we gen-

Therapy starts with exploration of the tooth erally recommend long-term therapy (30 to 60

root socket under general anesthesia. Generally, a days) of a potentiated sulfonamide. Typically, the

bone or tooth root fragment is identified, and drainage stops or at least diminishes during the

removal typically results in rapid healing of the course of therapy, only to return shortly after

st1rgery site. If bone or root fragments are not the antibiotics are discontinued. One publication

identified, alveolar bone damage may be present. reported successful medical therapy in three of

Because the alveolar bone between cheek teeth is five horses treated medically.17

relatively thin, damage to the alveolar bone may Occasionally lateral buccotomy and alveolar

expose the root of the adjacent tooth, which may plate removal are indicated for removal of teeth

result in periodontal disease in the adjacent tooth. with damaged crowns or teeth surrounded by

Inadvertent removal or loss of the alveolar sclerotic bone that would make removal by con-

plate can occur as a result of the original inflam- ventional oral extraction or repulsion difficult.11

matory process or during surgery. Removal of the Additionally, the caudal mandibular cheek teeth

alveolar plate such that the cement surface of the may be removed with this technique." Lateral

reserve crown of the adjacent tooth is exposed will buccotomy and alveolar bone plate removal are

result in incomplete healing as granulation tissue more tedious and time consuming than oral

will not adhere to exposed cementum. Similarly, extraction or repulsion and therefore are not

aggressive curettage of the socket can result in practical in field situations. A thorough descrip-

destruction of mesenchymal cells that would have tion of the technique is available elsewhere.v"

contributed to healing of the socket. Generally, Ideally, endodontic therapy for periapical

these errors will result in the development of infections in horses would allow for the tooth

chronic draining tracts and periodontal disease to remain in place, thus avoiding many of the

with the potential future need for removal of the complications associated with their removal .

•
affected adjacent tooth. Endodontic therapy requires special surgical

Repulsion of a mandibular tooth may result in skills, knowledge, and equipment and is generally

a fractured mandible if the dental punch is posi- a long general anesthetic procedure. The reported

tioned 011 the mandible rather than on the tooth long-term success rates have ranged from 440/o to

root or if the punch slides off the tooth root and 81 o/o.1,19,20

this redirection is not recognized by the surgeon. An alternative procedure for periapical infec-

This is a surprisingly easy complication if care is tions of the mandibular teeth has been re-

not taken to correctly position the punch and ported. 9'21 Periapical curettage involves identifying

continually monitor its orientation. Fortunately, the affected area, removing the overlying cortical

unless the mucous membranes have been pene- and cancellous bone, and identifying the affected

trated, these fractures can heal well following alveolus. Using curettage and irrigation, infected

removal of any small bone fragments. material is removed, with care taken to not disturb

Because of the orientation of the cheek teeth, the healthy root. The wounds are then left to heal

gaps created by tooth removal are gradually closed via second intention. Postoperative therapy con-

by movement of the cheek teeth to fill the gap. sists of removing the external serum crusting on

This movement creates another problem that will a daily basis and applying petrolatum to the skin

require continued tooth care for the rest of the around the wound to prevent serum scalding. The

horse's life. Tooth overgrowth can occur at either wounds are not flushed, and postoperative antibi-

the site of tooth removal or the first or last cheek otics and analgesics are recommended but not

tooth of the opposing arcade. required. The success rate has been reported to be