Does the chemistry in the saliva of Down syndrome children explain their low caries prevalence?

AIM: The present study focuses on the relationship between dental caries and saliva components such as phosphate, calcium, potassium, chloride as well as α-amylase in children with Down syndrome. MATERIALS AND METHODS: Forty-five Caucasian sibling pairs, with the mean age of 13±4 years compose the final sample. Stimulated whole saliva was collected from DS children and their siblings and an automatic analyser quantified the biochemical parameters. RESULTS: Down syndrome children presented lower caries rates. The salivary concentration of calcium, phosphate, potassium and chloride did not differ between DS and sibling children. In respect to α-amylases, the absolute salivary concentration as well as salivary secretion rate was similar between DS and sibling controls. CONCLUSION: In conclusion, no correlation between dental caries and salivary ionic composition as well as α-amylase secretion rate was found in DS children.

Fast and slow dynamics in a discotic liquid crystal with regions of columnar order and disorder.

Aromatic disk-shaped molecules tend to self-organize into a herringbone packing where the disks are inclined at angles ±Î¸ with respect to the axis of the column. In discotic liquid crystals this can introduce defects between stacks of limited length. In a C(3)-symmetric hexa-peri-hexabenzocoronene, solid-state NMR, x-ray scattering, and rheology identifies such a packing with θ=43° and stacks of about seven disks. Disordered regions containing defects fill the space in between the ordered stacks. Biaxial intra- and intercolumnar dynamics differing by eight decades are identified.

Modification of layered atelocollagen by ultraviolet irradiation and chemical cross-linking: structure stability and mechanical properties.

Physical and chemical modifications of atelocollagen materials have been carried out to improve their physical, chemical and biological properties. We have studied the influence of physical modification using ultraviolet irradiation and of chemical modification using hexamethylene diisocyanate on the physical properties of layered atelocollagen materials. The study evaluated the structural stability of cross-linked materials using swelling experiments. Influence on mechanical properties is also discussed.

[Hydrocele and cholesterol granuloma of the tunica vaginalis simulating a tumor in echography]. / Hidrocele y granuloma por colesterol de la túnica vaginal simulando un tumor en la ecografía.

OBJECTIVE: A case of cholesterol granuloma of tunica vaginalis, with an equivocal ultrasound image but typical histopathological picture, is described. PATIENT AND METHOD: A 33-year-old man complained of a painless scrotal mass of 17 years duration. The mass was 10 cm in diameter, could not be transilluminated and appeared as paratesticular and solid on ultrasound, suggesting a tumor. At operation an old hydrocele with cholesterol crystals and cholesterol granuloma of tunica vaginalis was found. A partial resection of tunica vaginalis was performed, sparing the testis. COMMENT: Cholesterol granuloma is a rare inflammatory reaction of tunica vaginalis, that may simulate an intrascrotal tumor on physical examination, on ultrasound and at operation.

Craniofacial features and specific oral characteristics of Down syndrome children.

AIM: This article intends to describe the characteristics of Down syndrome children in order to facilitate their management in the dental office. METHODS: A review of literature was made limited to articles published between 2003 and 2013. The article is based on a literature search in PubMed and the authors' clinical experience with the patient group. DISCUSSION: Individuals with Down syndrome are clinically characterized by generalized hypotonia, neurological, cardiac and respiratory problems and changes in their stomatognathic system. Almost all these patients have an occlusal disharmony, including anterior open bite, anterior and posterior crossbite, anterior proclination and underdevelopment of the maxilla and the midface. Dental anomalies such as hypodontia, peg-shaped teeth and enamel hypocalcification are also found. The dentomaxillofacial features have clinical implications in speech, nutrition, posture, ventilation and aesthetics, with enormous consequences in growth, development and social integration. CONCLUSIONS: When planning the dental treatment of patients with Down syndrome, dental practitioners should always consider their general health, in order to achieve a holistic and interdisciplinary approach.