Ultrastructure des microcalcifications du mésenchyme pulpaire des dents temporaires humaines

Scanning electron microscopic observations of pulp calcifications in deciduous molars were correlated with microradiographic findings.Numerous spherical calcifications were found in appearance similar to those in the permanent dentition.In a second type, mineralization took the form of diffuse deposits of calcium.The discrete diffuse foci coalesced into large islands of mineralized connective tissue.A third type of calcification was observed in which rhombic crystals were associated in a spherulitic pattern.The exact cause of the crystal formation is unknown. Moreover, as we are aware, the spherulitic calcifications have never been previously reported in this location.The preliminary results indicated that mineralization in the pulp of deciduous molars, takes a variety of forms, suggesting that calcium deposition can occur by different processes.L’objectif de ce travail est de corréler les observations au microscope électronique à balayage et en microradiographie, des micro-calcifications du mésenchyme pulpaire des molaires temporaires.Les résultats montrent que la pulpe contient de nombreuses calcifications sphériques ou ovalaires correspondant à la définition des pulpolithes.Un deuxième type de minéralisation a été trouvé sous la forme de dépôts diffus de sels de calcium. La coalescence des calcifications diffuses aboutit à la formation de plages plus larges de tissu minéralisé.Un troisième type de calcification est constitué de cristaux rhombes organisés sous la forme de sphérulites.Ce type de concrétions dont l’origine est inconnue ne paraît pas avoir été observée précédemment au microscope électronique à balayage.Ces résultats préliminaires montrent que les calcifications apparaîssent sous des formes variées suggérant que des mécanismes très différents gouvernent la promotion des dépôts de sels de calcium dans le mésenchyme pulpaire des molaires temporaires

Pneumatosis coli and incarcerated inguinal hernia

Background: A 53-year-old man was in follow-up for metastasized head and neck cancer. He was in a poor overall condition

Lipoma arborescens

Background: A 34-year-old man presented with recurrent and intermittent painful hydrops of the knee. This has started 13 years ago, after he underwent a reconstruction of the anterior cruciate ligament (ACL) and a partial resection of the lateral meniscus

Cementomimetics—constructing a cementum-like biomineralized microlayer via amelogenin-derived peptides

This is the published version. Copyright 2012 Nature Publishing GroupCementum is the outer-, mineralized-tissue covering the tooth root and an essential part of the system of periodontal tissue that anchors the tooth to the bone. Periodontal disease results from the destructive behavior of the host elicited by an infectious biofilm adhering to the tooth root and left untreated, may lead to tooth loss. We describe a novel protocol for identifying peptide sequences from native proteins with the potential to repair damaged dental tissues by controlling hydroxyapatite biomineralization. Using amelogenin as a case study and a bioinformatics scoring matrix, we identified regions within amelogenin that are shared with a set of hydroxyapatite-binding peptides (HABPs) previously selected by phage display. One 22-amino acid long peptide regions referred to as amelogenin-derived peptide 5 (ADP5) was shown to facilitate cell-free formation of a cementum-like hydroxyapatite mineral layer on demineralized human root dentin that, in turn, supported attachment of periodontal ligament cells in vitro. Our findings have several implications in peptide-assisted mineral formation that mimic biomineralization. By further elaborating the mechanism for protein control over the biomineral formed, we afford new insights into the evolution of protein–mineral interactions. By exploiting small peptide domains of native proteins, our understanding of structure–function relationships of biomineralizing proteins can be extended and these peptides can be utilized to engineer mineral formation. Finally, the cementomimetic layer formed by ADP5 has the potential clinical application to repair diseased root surfaces so as to promote the regeneration of periodontal tissues and thereby reduce the morbidity associated with tooth loss

Les perles d'émail des dents de lait.

A microradiographic study of 40 human deciduous teeth showed an unexpected high frequency (33%) of enamel pearls at the junctional interradicular line of the molars. An electron probe analysis showed that the composition of the pearls is similar to that of the coronal enamel. The pearls are located on normal dentine and are in contact with a hypermineralised layer separating cementum from dentine. It is hypothesised that the origin of this hyaline layer and the observed high frequency of pearls is not due to a possible differentiation of Hertwig sheath cells but results from variations of an usual biological process.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

DENT NEO-NATALE OU DENT PRELACTEALE?

SCOPUS: NotDefined.jinfo:eu-repo/semantics/publishe

Syphilitic parotitis

Background: A 45-year-old man presented with painless swelling of both parotid salivary glands. This swelling had been present for 1 year. Clinical examination showed a large, hard mass in the right parotid gland with diameter of more than 5 cm, a smaller similar lesion in the left parotid gland and lymphadenopathy of the right axilla

Histopathology of the interactions between alveolar bone and impacted dental germs in osteopetrotic op/op rats

Osteopetrosis, a general increase in bone density, is well-known as an autosomal recessive disease in several mammalian species. Compared with normal littermates, the osteopetrotic rats suffered from a complete failure of tooth eruption. Histologic and microradiographic studies show that the molars and the incisors developed a progressive ankylosis, the bone invades the germs and finally dissociates them. As early as the first days after birth, the incisors and the first molars are affected by the osteopetrotic process while the second and the third molars remain untouched. The periodontal membrane of the incisors is rapidly invaded by the osteopetrotic bone trabeculae. After the eleventh day, the process reached all molars. The germs were overlaid by an occlusal unresorbed bone. The formation of the gebernacular canal appeared to be independent of the prefunctional eruption.SCOPUS: ar.jFLWNAinfo:eu-repo/semantics/publishe