The prevalence of orofacial clefts in Qatar : a cross-sectional nationwide study.

Background: Cleft lip and palate are congenital craniofacial anomalies that significantly impact individuals and their families, both medically and psychosocially. The Qatari population has unique characteristics that are suggestive of a high prevalence of congenital anomalies: high consanguinity rate, large family size, advanced paternal age and high prevalence of certain genetic disorders. The lack of existing data concerning the epidemiology of cleft lip and/or palate in Qatar warrants a descriptive study addressing this topic.

Dental age estimation: development and testing of a reference data set for Qatari children, adolescents, and young adults aged between 5 and 25 years.

The purpose of this study is to establish and test a reference data set of dental development of Qatari subjects aged between 5 and 25 years. Radiographs of individuals aged between 5 and 25 years were re-used to establish a reference data set (RDS). A scheme comprising 8 tooth development stages (TDS) was used to assess all the teeth on the left side of the maxilla and mandible.

CD40-CD40L expression during orthodontic tooth movement in rats.

The aim of this study was to investigate the expression of the costimulatory molecules CD40 and CD40L in periodontal and bone cells in orthodontically treated and untreated teeth using immunohistochemistry. The upper first molars were moved mesially by a fixed appliance. In the experimental group, CD40+ cells were detected at both the tension and the resorption sides in fibroblast-, macrophage-, and dendritic-like cells.