Fragile-X syndrome: genetic aspects and stomatologic evaluations.

AIM OF THE WORK: The fragile-X syndrome is the most common cause of inherited mental retardation and it is associated with the FMR1 gene on X chromosome. The origin of anatomic anomalies of maxillo-facial complex is still discussed in literature. The authors describe the syndrome and report a clinical case. METHODS: Genetical and clinical aspects and the incidence of caries, periodontal disease and occlusal abrasion are reviewed. Occlusal conditions, particularly openbite and crossbite, are considered. RESULTS: The incidence of fragile-X syndrome is 1: 2000 in males and 1:4000 in females, despite this the syndrome is diagnosed with a lot of difficulties yet, because of extreme variability of the phenomenological aspects. Patients often show severe mental retardation, linked to a peculiar profile of cognitive, behavioural, and emotional dysfunction and to distinctive anatomic features, which become more evident after puberty. Concerning oral characteristics, it doesn't seem to be a significant association between the syndrome and the incidence of caries or periodontal diseases, while an ogival shaped palate is peculiar. CONCLUSIONS: Literature review suggests that when male patients with severe mental retardation without well-known cause are visited, the ipothesis of X-fragile syndrome should be considered. Even though the diagnostic hypothesis may arise from the observation of typical somatic features, the diagnosis can be confirmed only by genetical tests.

A less-invasive approach with orthodontic treatment in Beckwith-Wiedemann patients.

The Beckwith-Wiedemann syndrome (BWS) is a rare genetic disorder, linked to an alteration on the short arm of chromosome 11 that comprises multiple congenital anomalies. Macroglossia is the predominant finding, with subsequent protrusion of dentoalveolar structures, which results in a protruding mandible, anterior open bite, abnormally obtuse gonial angle and increased mandibular length. A less-invasive treatment with orthopaedic appliances in a patient with early tongue reduction is presented. This work summarizes the oral signs linked to macroglossia, and highlights the influence of macroglossia on mandibular growth structures. In our opinion, glossotomy could be carried out in the paediatric patient as a preventive measure in that it curbs the tongue's influence on skeletal growth and dramatically reduces the duration and extensiveness of subsequent treatment.

Multidisciplinary evaluation and clinical management of mesiodens.

Supernumerary teeth are a disorder of odontogenesis relatively common in the oral cavity and characterized by an excess number of teeth. The term mesiodens is used to refer to an unerupted supernumerary tooth in the central region of the premaxilla between the two central incisors. The complications associated with mesiodens include: lack of eruption of permanent teeth, the deviation of the eruption path, rotations, retention, root re-absorption and pulp necrosis with loss of vitality, and diastema. Early detection of mesiodens is most important if such complications are to be avoided. This report describes the treatment of a maxillary central incisor impacted by a mesiodens. The case initially required only surgical treatment, to remove the supernumerary tooth. Successively, orthodontic therapy was done to bring into position the left permanent central incisor, which erupted physiologically, but rotated 90 degrees around along its long axis.

Supernumerary teeth diagnosis and treatment approach. Six case reports.

Supernumerary teeth are relatively common in the general population, affecting the primary and the permanent dentition and have been reported in many genetic syndromes. They are classified according to form and shape. Seven different examples of hyperodontia are presented to highlight the numerical and morphological variation in dental abnormalities manifestations, empathising the importance of thorough clinical and radiological examination and of a correct therapeutic approach. The patients presented single or multiple hyperodontia, with particular interest for a 12 supernumerary teeth case. The clinical problems linked to supernumerary teeth were: impaction or ectopic eruption, crowding, possible root resorption of adjacent teeth. The therapeutical approach of supernumerary teeth varied on the position of the element in excess and on the complexity of the clinical case. In some cases the single extraction of the supernumerary tooth was indicated, while in other cases the extraction of the tooth was needed in addition to orthodontic treatment to gain sufficient space for the tooth with delayed eruption.

[Prenatal screening for Down's syndrome: a simplified method]. / Screening prenatale per la sindrome di Down: un metodo semplificato.

Prenatal screening for Down's syndrome (DS) can be achieved by combining maternal age risks and maternal serum additional parameters (AFP, HCG, uE3) by computer assisted statistical analysis. Nevertheless this measure of risk is far from broad and practical application in Italy, due to cultural and organization difficulties. So we suggest a different technical approach, the age specific risk being multiplied by the HCG/AFP likelihood ratio. HCG and AFP can be tested by an automated Elisa assay, and calculations performed by a simple method, excluding computer and software package use. About 100 pregnancies were evaluated both by a modified version of the Wald test and the method described hereafter. Using the automated HCG and AFP Elisa Testing and Crossley statistical calculation a higher False Positive Rate was observed. On the other hand no different Detection Rate was observed for the two tests. On a retrospective study we found that 5 sera from affected pregnancies were correctly identified both by the modified Wald test and the other method. It is concluded that, despite different False Positive Rates, the choice of which test to use depends on evaluation of local resources, one test being easier-to-perform and more sensitive, the other one probably being more specific but more difficult to perform.