Page 138 - Manual of Equine Field Surgery

134 HEAD AND NECK SURGERIES

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A B

Figure 22-4 Lateral and ventral views of mandibu-
Figure 22-2 Radiograph of 8-year-old horse.
lar and maxillary cheek teeth showing differences in

root structure. A, maxillary tooth with three roots

(some have four roots); B, mandibular tooth with two

roots.

Ideally, radiographs are taken at various inter-

vals throughout the procedure to ensure accurate

placement of the surgical site, removal of a

minimal amount of bone over the affected tooth,

and accurate placement of the punch. Radi-

ographs provide a11 accurate method of placing

the punch along the sagittal plane but not in the

frontal plane. The teeth accessible through the

sinuses are usually more toward midline than

anticipated (see Figure 21-3). 111 young horses

with long tooth roots that virtually fill the sinuses,

a trephine site that is very close to the infraorbital

canal will be necessary.

After the appropriate surgery site has been
Figure 22-3 Radiograph of 12-year-old horse.
selected, a 5-cin skin incision is made. The bone

overlying the tooth roots is removed with either

rongeurs or a trephine (Figure 22-5). The punch

need to be accessed through the maxillary sinus. is seated with the mallet, and a hand is positioned

The third upper molar is better accessed through in the mouth over the affected tooth to detect

a frontal sinus trephination site to allow position- vibrations from the punch. Radiographs can be

ing of a dental punch through the frontomaxillary taken at this point to verify accurate placement

opening into the caudal-maxillary sinus11 or a and orientation of the punch. Once it is verified

combination of frontal and maxillary trephina- that the tooth being punched is the affected tooth,

tion sites.12 Occasionally, a bone flap may be used several hard hits are generally required with the

to provide greater exposure to the tooth roots.13 mallet to loosen the tooth (Figure 22-6). The