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Concept: Cleidocranial dysostosis


BACKGROUND: Cleidocranial dysplasia (CCD) is a rare congenital autosomal dominant skeletal disorder. The disorder is caused by heterozygosity of mutations in human RUNX2, which is present on the short arm of chromosome 6p21. The incidence of CCD is one per million births. CCD appears spontaneously with no apparent genetic cause in approximately 40% of affected patients, and one in three patients has unaffected parents. The most prevalent features associated with CCD are aplastic or hypoplastic clavicles, supernumerary teeth, failed eruption of permanent teeth, and a hypoplastic maxilla. CASE PRESENTATION: A 13-year-old Caucasian boy presented with a chief complaint of delayed eruption of the permanent anterior teeth. The patient was subsequently diagnosed with CCD based on the clinical examination, panoramic X-ray, anterior-posterior and lateral cephalogram, and chest radiograph findings. The details of this case are herein reported because of the extremely low incidence of this disorder. CONCLUSIONS: CCD is of clinical importance in dentistry and medicine because it affects the bones and teeth and is characterized by many changes in skeletal patterning and growth. Particularly in dentistry, CCD is of great clinical significance because is associated with delayed ossification of the skull sutures, delayed exfoliation of the primary teeth, lack of permanent teeth eruption, multiple supernumerary teeth, and morphological abnormalities of the maxilla and mandible. Patients with CCD seek treatment mainly for dental problems. Knowledge of the pathogenesis, clinical characteristics, and diagnostic tools of CCD will enable clinicians to render the appropriate treatment to improve function and aesthetics. Early diagnosis of CCD is crucial for timely initiation of an appropriate treatment approach.

Concepts: Medical terms, Medical statistics, Chromosome, Teeth, Hyperdontia, Dental anatomy, Cleidocranial dysostosis, Permanent teeth



A review of numerous case reports was made, in order to demonstrate the possibilities for treatment of dental disorders in patients with Cleidocranial dysplasia (CCD). In this paper, our own report, including a diagnosis of the effect on the auditory system, is presented. In addition to the triad of CCD symptoms that include hypoplastic or aplastic clavicles, impacted and supernumerary teeth, delayed closure of fontanelles and cranial sutures, impairment of the hearing system resulting in conductive hearing loss also occurs. Our own report is based on the case of a 12-year-old CCD patient, in whom Cone Beam Computed Tomography (CBCT) revealed the presence of 12 supernumerary teeth. Furthermore, a clinical examination pointed to the presence of retained deciduous teeth and a delayed eruption of permanent teeth. Orthodontic-surgical procedures were implemented, in accordance with the literature. During the course of the orthodontic treatment, a decrease in auditory sensitivity was observed, for which reason hearing tests were also performed. Conductive hearing loss was detected. As such, it is important to remember that in such cases, auditory check-ups need to be performed between the many surgical and orthodontic interventions, which usually last a few years.

Concepts: Medical imaging, Auditory system, Otology, Teeth, Hyperdontia, Deciduous teeth, Fontanelle, Cleidocranial dysostosis


Cleidocranial dysplasia (CCD, MIM 119600) is a rare autosomal dominant disorder affecting bone, cartilage, craniofacial growth, and tooth formation leading to supernumerary teeth. Few reports delineate the genotype-phenotype correlations related to the variations in craniofacial morphology and patterning of the dentition and the complexity of treating patient’s malocclusion. Successful management of the craniofacial deformities in patients with CCD requires a multidisciplinary team of healthcare specialists. Approximately 70% of patients are due to point mutations in RUNX2 and <20% due to copy number variations with the remainder unidentified. There is no literature to date, describing the orthognathic management of CCD patients with deletion in one of the RUNX2 alleles. The purpose of this study was to evaluate the craniofacial morphology and dental patterning in a 14-year-old Caucasian female with CCD resulting from a novel microdeletion of RUNX2 in 1 allele. The CCD patient with RUNX2 haploinsufficiency due to microdeletion had decreased craniofacial bone and ankyloses in the permanent dentition. An altered extraction protocol of supernumerary teeth was followed in this patient. Craniofacial growth and morphologic analysis demonstrated atypical skull shape, persistent metopic suture, and decreased mandibular size.

Concepts: Gene, Genetics, Allele, Teeth, Genetic disorders, Haploinsufficiency, Hyperdontia, Cleidocranial dysostosis


In this review, we aimed to depict the clinical, radiological, and genetic features of cleidocranial dysplasia (CCD) and to suggest management guidelines, based on our experience of 8 cases, with an emphasis given to dental complications.The most common craniofacial features of CCD that stand out are a patency of the anterior fontanelle, an inverted pear-shaped calvaria, a hypertelorism, a general midface retrusion, and a mandible prognathism, associated with an excessive mobility of the shoulders, a short stature, and teeth abnormalities such as supernumerary teeth and failure of eruption, in particular. RUNX2 is the only gene in which mutation is known to cause CCD, but mutations are detected in only 65% of all patients with a clinical diagnosis of CCD. Panoramic radiography is a valuable adjunct in confirming the diagnosis of CCD.Our experience allowed us to conclude that orthodontically aided eruption should always be attempted. However, to stabilize the occlusion and to improve facial esthetics, we recommend associated orthognathic surgery. When orthodontic treatment is partially efficient, prosthetic treatment options bring satisfactory results, in terms of occlusion. Nevertheless, when orthodontic treatment fails, we recommend to preserve as many native teeth as possible, and to combine orthognathic preprosthetic surgery and implant-supported prosthesis.In any case, an individualized treatment protocol, depending on the needs and demand of the patient, the age at diagnosis and social and economic circumstances, should be put forward.

Concepts: Genetics, Cancer, Oral and maxillofacial surgery, Orthodontics, Haploinsufficiency, Hyperdontia, Fontanelle, Cleidocranial dysostosis


This clinical report describes the oral rehabilitation with implant-supported fixed dental prostheses in the maxilla and mandible of a patient with cleidocranial dysplasia. Cone-beam computed tomography and a tilted implant protocol in the mandible helped to establish a conservative approach for bone preservation, prevent surgical complications, enable proper implant positioning to avoid anatomic structures, and support the fixed dental prostheses.

Concepts: Medicine, Physician, Prosthetics, Anatomy, Dental implant, Cleidocranial dysostosis


A Thai mother and her two daughters were affected with tricho-rhino-phalangeal syndrome type I. The daughters had 15 and 18 supernumerary teeth, respectively. The mother had normal dentition. Mutation analysis of TRPS1 showed a novel heterozygous c.3809_3811delACTinsCATGTTGTG mutation in all. This mutation is predicted to cause amino acid changes in the Ikaros-like zinc finger domain near the C-terminal end of TRPS1, which is important for repressive protein function. The results of our study and the comprehensive review of the literature show that pathways of forming supernumerary teeth appear to involve APC and RUNX2, the genes responsible for familial adenomatous polyposis syndrome and cleidocranial dysplasia, respectively. The final pathway resulting in supernumerary teeth seems to involve Wnt, a morphogen active during many stages of development. © 2016 Wiley Periodicals, Inc.

Concepts: Family, Protein, Protein structure, Amino acid, Acid, Familial adenomatous polyposis, Hyperdontia, Cleidocranial dysostosis


Wormian bones are independent ossification centers found within cranial sutures or fontanelles. Though common in adult populations, their presence in children can be associated with several conditions such as osteogenesis imperfecta, hypothyroidism, pyknodysostosis, cleidocranial dysostosis, rickets, and acrocallosal syndrome. These conditions encompass a large range of clinical features but there has only been 1 other reported patient of exomphalos occurring concurrently with these ossicles. The authors present the case of a child with an anterior fontanellar Wormian bone, dysmorphic facial features, and exomphalos major born to unaffected parents. The pattern of features seen in this child did not closely match any condition commonly associated with Wormian bones. The only other reported case of both Wormian bone and exomphalos was in a child with acrocallosal syndrome who presented with more severe dysmorphic features than seen here. It is possible that this patient represents a previously unknown association between acrocallosal syndrome and exomphalos or a less severe variant of the condition. Conversely, this patient may possibly illustrate a newly discovered association between Wormian bones, facial dysmorphism, and midline abdominal defects.

Concepts: Skull, Osteogenesis imperfecta, Fontanelle, Cleidocranial dysostosis


  The aim of this article is to publish a literature review and report on a new case of cleidocranial dysplasia syndrome with 6p21.1-p12.3 microdeletion.

Concepts: Writing, Genetic disorders, Myelodysplastic syndrome, Cleidocranial dysostosis


While most supernumerary teeth are idiopathic, they can be associated with a number of Mendelian syndromes. However, this can also be a coincidental finding, since supernumerary teeth occur in 6% or more of the normal population. To better define this relationship, we analyzed the evidence for specific associations. We excluded conditions with a single affected patient reported, supernumerary teeth adjacent to clefts or other forms of alveolar disruption (as secondary rather than primary findings), and natal teeth, which can involve premature eruption of a normal tooth. Since, the cause of supernumerary teeth shows considerable heterogeneity, certain findings are less likely to be coincidental, such as five or more supernumerary teeth in a single patient, or locations outside of the premaxilla. We found only eight genetic syndromes with strong evidence for an association: cleidocranial dysplasia; familial adenomatous polyposis; trichorhinophalangeal syndrome, type I; Rubinstein-Taybi syndrome; Nance-Horan syndrome; Opitz BBB/G syndrome; oculofaciocardiodental syndrome; and autosomal dominant Robinow syndrome. There is also suggestive evidence of an association with two uncommon disorders, Kreiborg-Pakistani syndrome (craniosynostosis and dental anomalies), and insulin-resistant diabetes mellitus with acanthosisnigricans. An association of a Mendelian disorder with a low frequency manifestation of supernumerary teeth is difficult to exclude without large numbers, but several commonly cited syndromes lacked evidence for clear association, including Hallermann-Streiff syndrome, Fabry disease, Ehlers-Danlos syndrome, Apert and Crouzon syndromes, Zimmermann-Laband syndrome, and Ellis-van Creveld syndrome. © 2016 Wiley Periodicals, Inc.

Concepts: Diabetes mellitus, The Canon of Medicine, Syndromes, Teeth, Genetic disorders, Hyperdontia, Hypermobility, Cleidocranial dysostosis