Cleidocranial dysplasia: A report of two cases with brief review

Familial Cleidocranial Dysplasia: A Diagnostic Challenge

Cleidocranial dysplasia (CCD) is a rare genetic disorder affecting primarily the cranium, clavicle, and dental tissues. The expression of this disorder can vary widely in severity, even within the same family. Here we present a case report of an affected mother and son with classical manifestations of the disease.

Bilateral ‘kissing’ molars: A case report

‘Kissing molars’, were described by Van Hoof in 1973 as when the occlusal surfaces of impacted molars are united by the same follicular space and the roots point in the opposite direction. There are very few published cases in the literature, and it is an extremely rare form of impaction.

This manuscript concerns the diagnosis and management of a rare dentoalveolar clinical and radiographic presentation, which may be encountered by and be of interest to dental practitioners in both primary and secondary care.

An overview of the intraoral features and craniofacial morphology of growing and adult Japanese cleidocranial dysplasia subjects

BACKGROUND

Orthodontic treatment for cleidocranial dysplasia (CCD) requires an understanding of the nature of the retained deciduous teeth, supernumerary teeth, delayed eruption of the permanent teeth, and craniofacial morphology from childhood to adulthood. This study aimed to provide an overview of the intraoral and craniofacial characteristics of growing and adult Japanese CCD subjects.

METHODS

We assessed cross-sectionally the intraoral features of 28 CCD subjects (males, 15.3 ± 7.0 years; females, 15.2 ± 5.1 years) using orthopantomograms and photographs. Mean facial diagrams (profilograms) of 3 age groups (5-10 years, 11-14 years, over 15 years: adult) were constructed, and linear and angular measurements of 2 age groups (under 15 years, adult) were performed by using cephalograms. The data were compared with Japanese standards.

RESULTS

A mean of 11.7 and 8.4 retained deciduous teeth, 10.4 and 15.8 erupted permanent teeth were observed in the adult males and females, and a mean of 6.8 and 5.3 supernumerary teeth were observed in all males and females, respectively. A positive correlation was found between the number of supernumerary teeth and the age at initial visit. Cephalometric analysis showed an average to anteriorly positioned maxilla, a tendency for counter-clockwise rotation of the ramus, and a prognathic mandible in all groups.

CONCLUSIONS

The number of supernumerary teeth increased with age. The maxilla was average to anteriorly positioned, and the mandible was counter-clockwise rotated and prognathic for all groups. These characteristic craniofacial morphologies and changes of intraoral conditions at different ages in CCD patients should be considered when proposing rational orthodontic treatment plans.

Molecular Genetics of Cleidocranial Dysplasia

Cleidocranial dysplasia (CCD) is a genetic disorder with an autosomal dominant inheritance pattern. CCD characterized by abnormal clavicles, patent sutures and fontenelles, supernumerary teeth and short stature. Approximately 60-70% of CCD patients have mutations in the RUNX2 gene. The RUNX2 gene is an essential transcription factor for chondrocyte maturation, osteoblast differentiation and bone formation. Runx2 regulates mesenchymal cell proliferation in sutures and suture closure by inducing the signaling pathways of the genes of Fgf, Pthlh, hedgehog and Wnt. Material and Methods: We summarized molecular genetics aspects of CCD. Result: Approximately 94% of CCD patients have dental anomalies, the most common of which are supernumerary tooth. Dental anomalies are not determined solely by gene mutations of RUNX2, but are also affected by modifier genes, environmental factors, epigenetic factors and copy number variations. Conclusion: a definite diagnosis of CCD should include the patient's clinical history, symptoms and signs, as well as genetic analyses.

Cleidocranial dysplasia syndrome with epilepsy: a case report

Background

Cleidocranial dysplasia is a rare autosomal dominant disorder resulting in skeletal and dental abnormalities due to the disturbance in ossification of the bones. The prevalence of CCD is one in a million of live births, and epileptic seizures are rarer in this disease.

Case presentation

Herein, we present a case of a 10-year-old girl, who not only suffered with cleidocranial dysplasia, but experienced frequent seizures. We initiated an anti-epileptic treatment for this patient with dose adjustments to her weight of levetiracetam (10 mg/kg, bid) for 3 months. The epileptic seizures were controlled, but the intelligence level and control of epilepsy need to be followed up for a longer duration.

Conclusions

In clinical practice, if a patient has unusual facies, typical clavicle defect, skull bone enlargement, and unclosed anterior fontanelle, we should consider the possibility of cleidocranial dysplasia, genetic detection are helpful to make a confirmed diagnosis. In such cases, early diagnosis and treatment is important to correct deformities and improve the quality of life of patients.