Page 781 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

756 CHAPTER 4

VetBooks.ir misleading and unnecessary. There is little evi- powered tools. The latter are ever increasing in effi-
ciency, popularity and usage. Many models are avail-
dence that removal of non-pathological dental
tissue, other than removing sharp foci traumatising
variety of contact angles are desirable. Such instru-
soft tissues and thereby causing soft-tissue pain or able but those with small heads, water cooling and a
impeding mastication, is of any great benefit to the ments are capable of excessive rasping leading to
horse. Masticatory wear in a normally eating horse pulpar and sensitive dentine exposure in incompetent
will produce surfaces and edges that are reasonably hands. Short periods of contact and frequent checking
angular and hence efficient for chewing. In the har- on progress enable careful treatment to be executed.
nessed and performing horse, bridle side-pieces may Although some animals will tolerate these well, they
exert pressure over these edges resulting in muco- can be used with much greater safety and precision
sal trauma. Stabled horses fed a high proportion of if the animal is sedated, thereby enabling visual con-
non-grazed food probably perform less masticatory trol. In addition, there is evidence that dental rasping
movement than their grazing ancestors, and some is stressful for the horse and sedating it may decrease
compensation for this lack of occlusal wear can this. Ideally, rasping should be done under visual con-
potentially be of benefit. After a careful visual and trol to enable careful control and precision. Manual
digital palpation these overgrown prominences can instruments are safe in less restrained horses and
be appraised for reductive treatments. Typically, the effective when used proficiently but have the potential
buccal aspects of maxillary cheek teeth and lingual for repetitive strain injuries to the veterinarian. The
aspects of mandibular dentition are prone to develop use of head-stands and mirrors is increasingly popular
overgrowths, sometimes termed ‘enamel points’. In to aid with the precision of dental rasping.
addition, rostral overgrowths or hooks can develop Teeth with exposed pulps, gingival tracts, caries or
on the caudal mandibular molars and rostral maxil- dental fracture should be appraised radiographically,
lary premolars. Rasping to prevent the development and treatments advised based on the viability of the
of these is prophylactically sensible. teeth and the impact of such treatments on the patient.
Rasping can be done with manual instruments Treatments should be recorded on a dental chart and a
or the increasingly popular rotary or reciprocating plan made for re-examination or follow-up treatment.

NON-DENTAL DISEASE OF THE ORAL CAVITY

CLEFT PALATE (PALATOSCHIASIS) The signs are usually evident during a cursory
examination at birth or once the foal commences
Definition to suck. Foals with a cleft palate present with nasal
Cleft palate is a congenital defect resulting in an reflux during feeding, as milk entering the oral
incomplete symphysis, which can affect the upper lip cavity passes into the nasal cavity and exits via the
and hard palate but which most commonly involves nares bilaterally during sucking. Such foals are able
the caudal portion of the soft palate (Fig. 4.73). to swallow but some aspiration can occur in the first
few days. Oral and digital examination of the hard
Aetiology/pathogenesis and soft palate will reveal a defect, which varies from
The defect is the result of failure of the lateral pala- approximately 1 cm to the whole caudal portion of
tine processes to fuse, which normally occurs at the soft palate. Complications result from the dys-
approximately day 47 of gestation. The heritability phagia and can include failure of passive transfer
has not been established in horses. of gamma- globulins from colostrum, dehydration,
hypoglycaemia and aspiration pneumonia.
Clinical presentation
Primary cleft palate (affecting the upper lip and Diagnosis
rostral hard palate) presents as a sagittal facial defor- Clinical detection of the lesions may be further
mity with incomplete aponeurosis of the upper lip. confirmed by nasal or oral endoscopy. The sagittal