Obstructive sleep apnea syndrome (OSAS) in children with Class III malocclusion: involvement of the PHOX2B gene.

Purpose: The aim of this study is to provide new molecular approaches to the children with obstructive sleep apnea syndrome by evaluating the possible involvement of the PHOX2B gene, notoriously associated to congenital central hypoventilation syndrome (CCHS), in Class III malocclusion.

Methods: Fifty subjects with Class III malocclusion, aged from 8 to 14 years, and with history of sleep apneic episodes, and 20 age-matched controls were submitted to genomic DNA examination from oral cells to specifically analyze the PHOX2B genotype.

Results: Point "silent" mutations affecting different nucleotides of the PHOX2B gene were observed in 32 % of patients with Class III malocclusion and never in controls (0 %).

A novel method for banking dental pulp stem cells.

Dental pulp stem cells (DPSC), a cell type of mesenchymal origin showing high proliferation and plasticity, are an emerging source of adult stem cells offering interesting features in view of potential applications in regenerative medicine. These features prompted us to develop a new method to cryopreserve DPSC inside a whole tooth, thus avoiding the need to purify the cells before cryopreservation and reducing the initial costs and workload of tooth banking. In this study we cryopreserved 4 human deciduous whole teeth after digging micro-channels into the tooth with an Nd:YAG laser beam (laser piercing) to allow the cryopreservative to reach the dental pulp and preserve the cells at -80°C.

Orthodontic treatment in a patient with cleidocranial dysostosis.

Cleidocranial dysostosis is a rare congenital skeletal disorder, associated with clavicular hypoplasia or aplasia, delayed closure of cranial fontanels, brachycephalic skull, delayed exfoliation of primary dentition, eruption of permanent teeth, and multiple supernumerary and morphologic abnormalities of the maxilla and mandible. The disorder is caused by mutation in the CBFA1 gene, on the short arm of chromosome 6p21. The prevalence of cleidocranial dysostosis is estimated one per million, without sex or ethnic group predilection.