Cleidocranial dysplasia: clinico-radiological illustration of a rare case

Abstract

Cleidocranial dysplasia is an autosomal dominant condition caused by mutation of RUNX2, characterized by generalized dysplasia of the bones and teeth. Affected individuals have short stature, atypical facial features, and skeletal anomalies affecting mainly the skull and clavicle. The dental manifestations are mainly delayed exfoliation of the primary teeth and delayed eruption of the permanent teeth, with multiple impacted supernumeraries, and absence of cellular cementum. The frequency of this disorder is 1 per million individuals. Here we report a rare case of CCD in a 9-year-old male patient having most of the characteristic features of this syndrome. Interestingly, disorganized dentinal tubules were found in the roots of an extracted deciduous first molar, which seems to be a unique feature not reported previously.

Cleidocranial dysplasia: Two unique cases

“…[9] The genetic studies demonstrated microdeletion of chromosome band 6p21, t (6;18) (p12; q24) translocation and pericentric inversion of the chromosome. [6,10] The gene aff ected is believed to be core binding factor activity 1 (CBFA1). CBFA1 is crucial for diff erentiation of stem cells into osteoblasts, so any defect in this gene will lead to defect in the membraneous and endochondral bone formation.…”

“…The cellular cementum is completely absent, and acellular cementum is increased on the roots of the aff ected teeth. [6] Underdeveloped paranasal sinuses are also noted. Vertebral defects with scoliosis, kyphosis or lordosis, pelvic bony abnormalities and anomalies of phalangeal, tarsal, metatarsal, carpal and metacarpal bones are also present.…”

“…[8] Skull radiographs show brachycephaly, open skull sutures, small sphenoid bones, and calvarial thickening over the occiput. [6] Wormian bones are also seen in the coronal and lambdoid regions because of the abnormal ossifi cation pattern. [14] Chest radiography shows a narrow thorax, oblique ribs and, [6] hypoplastic, aplastic, or discontinuous clavicles.…”

“…[6] Wormian bones are also seen in the coronal and lambdoid regions because of the abnormal ossifi cation pattern. [14] Chest radiography shows a narrow thorax, oblique ribs and, [6] hypoplastic, aplastic, or discontinuous clavicles. [3] Bell shaped small thoracic cage having short ribs is also seen.…”

“…[3] Since, CCD shows generalized dysplasia of bones and teeth "dysplasia" is more appropriate instead of "dysostosis". [6] Prominent supraorbital and infraorbital ridges, exorbitism due to defi cient orbital volume and frontal bone thickening results in the characteristic skull appearance in CCD known as "Arnold head." [2] This appearance is similar to descendants of a Chinese family named Arnold.…”