Craniofacial and dental development in Costello syndrome.

Costello syndrome (CS) is a RASopathy characterized by a wide range of cardiac, musculoskeletal, dermatological, and developmental abnormalities. The RASopathies are defined as a group of syndromes caused by activated Ras/mitogen-activated protein kinase (MAPK) signaling. Specifically, CS is caused by activating mutations in HRAS. Although receptor tyrosine kinase (RTK) signaling, which is upstream of Ras/MAPK, is known to play a critical role in craniofacial and dental development, the craniofacial and dental features of CS have not been systematically defined in a large group of individuals. In order to address this gap in our understanding and fully characterize the CS phenotype, we evaluated the craniofacial and dental phenotype in a large cohort (n = 41) of CS individuals. We confirmed that the craniofacial features common in CS include macrocephaly, bitemporal narrowing, convex facial profile, full cheeks, and large mouth. Additionally, CS patients have a characteristic dental phenotype that includes malocclusion with anterior open bite and posterior crossbite, enamel hypo-mineralization, delayed tooth development and eruption, gingival hyperplasia, thickening of the alveolar ridge, and high palate. Comparison of the craniofacial and dental phenotype in CS with other RASopathies, such as cardio-facio-cutaneous syndrome (CFC), provides insight into the complexities of Ras/MAPK signaling in human craniofacial and dental development.

[Orthodontic anomalies and secular trend in formation of the orofacial cranium]. / Ortodontické anomálie a sekulární trend v utvárení orofaciální oblasti.

BACKGROUND. The aim of the study was to compare craniofacial and dental characteristics of contemporary and historical populations and elucidate some etiological aspects of malocclusion. METHODS AND RESULTS. Con-temporary cohort of 703 university students and three historical samples (73 skulls from 9th century, 344 skulls from the 10th to 14th century and 210 skulls from the 14th to 18th century were examined. Measurements of craniometric and anthropometric points were done. The width of jaws was examined in Pont's points. Björk´s method for epidemiological registration of malocclusion was used; teleroentgenograms were examined as well. Broader dental arches regardless of the type of skull and significantly lower frequency of serious malocclusions were proven in historical population. CONCLUSION. The extreme increase of serious malocclusions in the contemporary population is more probably caused by civilisation factors than secular trend in formation of skull. .

Orthodontics and foetal pathology: a personal view on craniofacial patterning.

This article summarizes the essentials of studies on the craniofacial skeleton performed over 17 years. It presents data from research into foetal pathology resulting in new views on craniofacial patterning and/or fields for further discussion. The fields described cover all areas seen on profile, frontal, and panoramic radiographs. The fields are the theca, frontonasal, maxillary, palatine, and mandibular together with the cerebellar field and cervical spine. Regional fields in the dentition are described according to the pattern of peripheral nerve innervation. Studies on severely malformed foetuses show that the malformation can occur solely within a single field or in several fields. This is the background for these personal views on craniofacial patterning. These new views may assist in the diagnosis and interpretation of malformations in the cranium and dentition.

Estudio descriptivo de la oclusión temporaria en niños de la ciudad de Córdoba, Argentina / A descriptive study of temporary occlusion in children from Cordoba city, Argentina

Esta investigación revela las características oclusales de la población infantil de la ciudad de Córdoba, Argentina. Se realizó un estudio transversal de una muestra representativa, perteneciente al estudio CLACYD (Córdoba, Lactancia, Alimentación, Crecimiento y Desarrollo). Se seleccionaron 290 niños de ambos sexos a los 5 años de edad. Los objetivos fueron obtener datos epidemiológicos de la oclusión dentaria temporaria, describir sus características normales y anormales, relacionándolas con el estrato social de las familias. Los datos fueron analizados con el paquete estadístico SPSS/PC 4.0. Se evaluaron las diferencias de distribución de las categorías de las variables, utilizando las pruebas de Chi cuadrado, considerándose una diferencia estadísticamente significativa cuando p<-0.05. Los resultados obtenidos se expresaron en proporciones con intervalos de confianza del 95 por ciento. Del total de la población un 55.2 por ciento tenía oclusión normal, no evidenciándose diferencias estadísticamente significativas con relación a estratos sociales (alto, medio y bajo). En cuanto a las maloclusiones observamos prevalencia de sobremordida en un 20.9 por ciento de los niños

[Fetal ventilation and craniomaxillary development]. / Ventilation foetale et développement cranio-maxillaire.

Data acquired by means of color Doppler ultrasound very explicitly suggest what the role of the fetal ventilation and nasal capsules in the morphogenesis of the maxillary prognathism, turbinates, nasal valves and nasopharynx could be. Furthermore, the dysmorphologies observed in Apert or Crouzon craniosynostosis, achondroplasia or unilateral cleft lip would also testify that the influence of the fetal ventilatory dynamics goes beyond the limits of the face and extends to the cranial base and the cranium. The wealth of raised hypothesis thanks to the contribution of this imaging system could question the validity of some conceptions of the fetal craniomaxillary morphogenesis.

[The origin of class II]. / La Classe II--son origine?

Profound knowledge of craniofacial growth is of utmost importance to the clinician in order to establish a treatment plan which respects the growth type of each patient. Different growth processes and possible etiological factors leading to a skeletal Class II are discussed. Only a comprehensive analysis in all three dimensions will allow adequate choice of treatment procedure.