Cleidocranial dysplasia, previously known as cleidocranial dysostosis, is a rare hereditary disease of unknown etiology characterized by abnormalities in the skull, jaws, shoulder girdle, as well as abnor­ malities of the dentition. The disease usually follows an autosomal dominant mode of transmission. This is a report on a case in a 25-year-old Saudi female from Gizan, Saudi Arabia, which seemes to be the first case reported in the Kingdom. An outstanding feature of this case is that it did not follow a familial pattern of inheritance since the patient is the only member of the family suffering from such disorder. The abnor­ malities present in the dentition are described together with the associated skeletal malformations. The clin­ ical and radiographic findings, as well as the hereditary pattern of the disease as described in the literature, are discussed. The dental management of these cases is reviewed.

 
Cleidocranial dysplasia was referred to as cleidoc­ ranial dysostosis prior to the conference on the nomenclature for constitutional disorders of bone held in Paris 1969, the proceedings of which were reprinted by Mekusick and Scott.1 The syndrome was first described by Marie and Sainton in 1898,2 as a rare developmental condition in which the leading features were (1) aplasia of the clavicles, (2) exaggerated development of the transverse diame­ ter of the cranium, (3) delayed closure of the fon­ tanells, and (4) disorders of the jaws and dentition. Soule,3 however, reported that the first case was described by Cutter4 in 1897. Occasionally, the cranial and the clavicular abnormalities are lack­ ing, and because of this, Rineheart5 suggested that the name be changed to "mutational dysostosis". The condition is often hereditary, however, several cases were reported in which neither a familial nor a hereditary history was discovered.6-7
This article is a report on a case of cleidocranial dysplasia in a Saudi female from Gizan, Saudi Arabia, which seems to be the first such disorder to be reported in the Kingdom.
Case Report:
On November 1984, a 25-year-old Saudi female was referred to the Dental Department of King Fahad Central Hospital in Gizan for replacement of some missing teeth.
The appearance of the patient, with a large head, small face, drooping shoulders, and stunted gait, caught attention from the first glance. The patient refused clinical photographs.
Family History
The patient, unmarried, was the eldest of two brothers and one sister. None of the siblings and neither of the parents were affected. Her past med­ ical history was non- contributory.
Examination
The patient was short, being 147 cm in height, and stout, weighing 52 kg. She had a large head relative to her stunted gait. The frontal and pariental eminences were conspicuous with flattening of the forehead and the cranial vault, thus, giving the cranium a box-shaped appearance. The cheeks were flattened, stretching the nasolabial folds, giv­ ing the patient's face a sad expression. The maxilla appeared small relative to the mandible in a pseudoprognathic appearance.
Oral Findings
The patient had a narrow highly arched palate. The dentition consisted mainly of deciduous teeth with few permanent teeth in either arch. The man­ dibular incisors were missing and replaced by a fixed bridge using the mandibular deciduous canines as bridge abutments. Some other teeth, however, were missing. Mild inflammation of the entire marginal gingiva was observed. The oral hygiene was generally poor. The oral mucosa and tongue were otherwise normal.
Investigations
Results from blood chemistry and urine analysis were within the normal limits of value.
Radiographic Examination
Several radiographic views were taken.
A pantomogram revealed unerupted permanent teeth and a large number of impacted supernumer­ ary teeth in both the upper and lower jaws. The bone density and architecture in both jaws were otherwise normal. [Fig. 1]
Skull views: The postero-anterior view showed a brachy-cephalic skull with a large transverse diameter. The frontal and parietal eminences were quite noticeable. The anterior and posterior fon­ tanells were widely opened with the suture shadows excessively prominent. The maxilla and zygomatic bones were relatively small. [Fig.2]
In Water's view, the frontal air sinus was entirely absent. Both maxillary antra were small and under developed. [Fig. 3]
Lateral skull view showed prominent suture shadows with numerous wormian bones around the lambdoid suture. The maxilla also appeared small relative to the mandible. [Fig.4]
X-ray of the chest showed defective formation of both clavicle and narrowing of the thoracic cage. [Fig. 5]

Based on the foregoing, the diagnosis of cleidoc­ ranial dysplasia was made. Since 1897, over 700 of cleidocranial dysplasia cases had been described in the literature.8,9,10 A familial incidence was recorded in approximately two-thirds of the reported cases, and the condition was found in as many as five successive generations.11 When inh­ erited, it appears as non-sex-linked, Mendelian dominant characteristic and transmittable by either the mother or father who manifests the defor­ mities.11 In those cases which appeared to have developed sporadically, as with the case presented here, it had been suggested that they represented a recessively inherited disease, or more likey, either an incomplete penetrance in a genetic trait with variable gene expression or a true new dominant mutation.12
The narrow, highly arched palate, the retention of deciduous teeth, delayed eruption of permanent teeth,   and  the  presence  of large  numbers of impacted supernumerary teeth are all classical oral findings in cleidocranial dysplasia.13
The skull deformities observed in this case were all consistent with cleidocranial dysplasia.11,13,14 Although the maxilla appeared smaller relative to the mandible, recent studies based on cephalomet- ric analysis point out that 70% of affected patients had larger mandibles than the controls.15 How­ ever, these findings remain to be confirmed. An outstanding feature of this case was the defective formation of both clavicles. Complete absence of the clavicles, however, was reported only in 10% of the cases of cleidocranial dysplasia.13
Little or nothing is known about the etiology of this condition .11,13 It has been once thought that the disorder was due to some intrinsic systemic defor­ mities arising during the first week of embryonic life, and affecting the bones which develop in the mem­ brane. It is now recognized that the condition affects the entire bony skeleton and extraskeletal structures, such as skeletal muscles.13
There is no treatment for cleidocranial dysplasia, although care of the oral condition is important. The retained deciduous teeth should be restored if they become carious.13 More recently, several attempts were made to induce eruption of the per­ manent teeth through surgical exposure, but the results remain to be evaluated.16