including pachyonychia congenita, Ellis-van Creveld syndrome, and Hallermann-
Streiff syndrome.
Natal or neonatal teeth are often mobile because of limited root development and may
be a danger to the airway if they are inhaled. The crowns may be abnormal in form
and the enamel may be poorly formed or thinner than normal. The mobility of the
tooth frequently also causes inflammation of the surrounding gingivae. Trauma to the
ventral surface of the tongue may cause ulceration (877HFig. 13.44) and difficulty during
feeding may occur if the infant is breastfed.
Treatment
Local measures such as smoothing of the sharp edges of the tooth with a rubber cone
in a dental handpiece may help resolve the ulceration. In a number of cases, if the
tooth is markedly loose it should be extracted as it is unlikely to form a useful part of
the dentition. Firm application of Spencer-Wells forceps to the tooth crown is advised,
followed by minor local curettage to remove remains of the developing tooth-germ at
that site.
878H
Fig. 13.44 Natal teeth 71, 81. Ulceration of
ventral surface of tongue.13.8.2 Delayed eruption
Delayed eruption of primary teeth may arise from either systemic or local factors. It
may be associated with prematurity or low birth weight.
Delayed eruption of teeth of both dentitions may occur in association with Down
syndrome and Turner's syndrome. Delayed eruption may also be associated with
nutritional abnormalities or endocrine disorders such as hypothyroidism or
hypopituitarism.
Cleidocranial dysplasia is an autosomal dominant condition characterized by aplasia
or hypoplasia of the clavicles and widespread cranial changes. These include a
brachycephalic skull (short in the antero-posterior dimension), frontal and parietal
bossing, hypoplasia of the maxilla and zygomatic arches, hypertelorism as well as
delayed closure of the anterior fontanelle and skull sutures. Multiple wormian bones
are present in the line of the cranial sutures, particularly the lambdoid suture. With
respect to the jaws, the most striking dental feature is the presence of multiple
supernumerary teeth, particularly of the permanent dentition, and particularly in the
anterior parts of the jaws. Permanent tooth eruption is often delayed or there is failure
of eruption, partly because of the number of supernumerary teeth. The primary teeth