21 Palatal Defects (Congenital)

DEFINITION/OVERVIEW



  • Primary palatal cleft (palatoschisis): located at the junction/suture of the incisive bone and one or both of the maxillary processes; may be associated with cleft lip (cheiloschisis) (Fig. 21-1)
  • Secondary palatal cleft: defect on midline behind incisal area involving the soft and/or hard palate


x25AA001rs Figure 21-1 Primary palatoschisis with cheiloschisis of a puppy.


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c21uf003ETIOLOGY/PATHOPHYSIOLOGY



  • Dogs/cats

    • Failure of the developing paired palatine processes to fuse properly
    • As in people, the cause is thought to be multifactorial: contributory risk genes together with environmental influences (teratogen exposure) will result in a cleft defect if a threshold is reached
    • In many cases with a wide variety of breeds, there likely has been an intrauterine insult during fetal development

      • Teratogens include infectious agents, corticosteroids, excessive vitamin A or D, X-ray radiation, griseofulvin, hormones, and nutritional deficiencies

    • In some, genetic predisposition: incomplete penetrance in shih tzu

c21uf004SIGNALMENT/HISTORY



  • Any breed or gender if intrauterine insult
  • Prevalence reported in brachycephalic breeds, beagles, cocker spaniels, dachshunds
  • Secondary cleft readily apparent at birth if external cleft lip (cheiloschisis) is present
  • Primary cleft: apparent with oral exam that each newborn should receive (Fig. 21-2)

    • Newborn may have history of poor nursing, and decreased growth, with milk draining or bubbling from nose


x25AA001rs Figure 21-2 Primary palatoschisis with cheiloschisis of a young adult.


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c21uf005CLINICAL FEATURES


Dogs



  • Primary cleft palate

    • Unilateral or bilateral cleft at rostral aspect of maxilla

      • Often associated with cleft lip

    • Seldom has clinical signs unless associated with a secondary cleft palate
    • Dental anomalies, such a tooth number, size, and morphology are common in both deciduous and permanent dentition; the maxillary third incisor in the vicinity of the cleft is frequently involved

  • Secondary cleft palate

    • Midline defect can be mild to extensive, involving hard and/or soft palate
    • Unable to nurse effectively without proper suction

      • Poor growth, unthrifty
      • Milk drainage from nose, gagging, sneezing
      • Can progress to rhinitis or even aspiration pneumonia, which can be fatal

Cats



  • Less common than in dogs

c21uf006DIFFERENTIAL DIAGNOSIS



  • Traumatic palatal defects

c21uf007DIAGNOSTICS



  • Complete oral examination: this should be an essential part of every newborn examination
  • Intraoral radiograph to assess the extent of osseous involvement (Fig. 21-3)
  • Appropriate preoperative diagnostics when indicated prior to procedure

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May 22, 2017 | Posted by in GENERAL | Comments Off on 21 Palatal Defects (Congenital)

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