Craniofacial abnormalities in a murine model of Saethre-Chotzen Syndrome.

Background: Saethre-Chotzen Syndrome (SCS) is an autosomal dominant syndrome that occurs due to a mutation or deletion of the Twist1 gene at chromosome 7p21. Our aim was to conduct a morphometric analysis of the craniofacial features in the mouse associated with a Twist1 mutation.

Methods: Micro-computed imaging was conducted for the skulls of forty skeletally mature mice, equally distributed by sex (male and female) and two genotypes (Twist1 or murine model of SCS; and Twist1 or wild-type).

The human medial pterygoid muscle: Attachments and distribution of muscle spindles.

Published descriptions about the sites of origin of the human medial pterygoid muscle vary and there are few reports on the distribution and density of muscle spindles in this muscle. We aimed to: (1) determine the extent of anatomical variability in the origins and insertions of the superficial and deep heads of the human medial pterygoid muscle and (2) determine the extent of variation in the distribution of spindles in the two heads of the muscle. Thirty-nine human cadaver hemi-heads were dissected and the attachments of the medial pterygoid muscle examined.

The Influence of Chorion Type on Health Measures at Birth and Dental Development in Australian and Dutch Twins: A Comparative Study.

Chorion type may significantly influence the prenatal environment of twins. This study explored the associations between chorion type and gestational age, birth weight, birth length, and the timing of emergence of the first primary tooth in two populations of twins, Australian and Dutch. Additionally, we investigated the relationship between chorion type and birth weight discordance (BWD) in order to determine whether a significant relationship existed between discordance in birth weight and discordance in the timing of emergence of the first primary tooth.

Prevalence of infraocclusion of primary molars determined using a new 2D image analysis methodology.

Background: The reported prevalence of infraocclusion varies widely, reflecting differences in definitions and measurement/scoring approaches. This study aimed to quantify the prevalence and extent of infraocclusion in singletons and twins during the late mixed dentition stage of dental development using a new diagnostic imaging method and objective criteria. The study also aimed to determine any associations between infraocclusion and gender, arch type, arch side and tooth type.

Infraocclusion: Dental development and associated dental variations in singletons and twins.

Objective: The aim of this study was to investigate the prevalence of selected dental variations in association with infraocclusion, as well as determining the effects of infraocclusion on dental development and tooth size, in singletons and twins.

Design: Two samples were analysed. The first sample comprised 1454 panoramic radiographs of singleton boys and girls aged 8-11 years.