anatomy

Abstract: Armadillos are bitten by several species of flea. Females of the genus Tunga penetrate the epidermis and when in place are fertilised by males, after which the abdomen swells enormously to form a ’neosome’. Within the penetrans group, T. perforans, makes lesions that perforate the osteoderms within the integument to form ~3 mm diameter cavities occupied by a discoid neosome. We examined these lesions in carapace material from animals which had died in the wild to see whether we could recruit evidence as to how they may be generated, either by the insect or by the host....

Abstract: Objectives: Differences in the mineral concentration (MC) level of dental enamel may represent a precursor of white spot lesions adjacent to fixed orthodontic brackets. The aim of the current in vitro study was to compare the MC level central, occlusal and cervical to orthodontic attachments. Methods and materials: A total of 16 enamel blocks were obtained from sound human premolar samples extracted for orthodontic reasons. The buccal portion of the dental enamel blocks was divided into central, occlusal, and cervical regions and then imaged and measured to calculate the level of MC using quantitative X-ray microtomography methods (XMT) at each site....

Abstract: Inhalant use disorder is a psychiatric condition characterized by repeated deliberate inhalation from among a broad range of household and industrial chemical products with the intention of producing psychoactive effects. In addition to acute intoxication, prolonged inhalation of fluorinated compounds can cause skeletal fluorosis (SF). We report a young woman referred for hypophosphatasemia and carrying a heterozygous ALPL gene variant (c.457T>C, p.Trp153Arg) associated with hypophosphatasia, the heritable metabolic bone disease featuring impaired skeletal mineralization, who instead suffered from SF....

Abstract: The coronal portion of the developing upper third molar may be impacted by the developing roots of the second molar. At the relevant age – roughly from 10 to 13 years – both organs are largely soft tissues when and where they collide. It is obviously not possible to obtain tissue from both teeth whilst they are developing, but a frequent after-effect of such collisions is extraction of the third molar....

Abstract: Starting from scratch, if one wanted to correlate light microscopical (LM) and X-ray microtomographic (XMT, micro-CT) findings from the mineralized tissues - bone and calcified cartilage in the skeleton and dentine, enamel, and cementum in teeth - one could simply examine the same, resin embedded sample with at least one flat surface by confocal scanning reflection and/or fluorescence light microscopy and XMT. However, we are frequently presented with ready-made ‘ground’ sections mounted in Canada balsam or DPX on 25mm wide ~1mm thick glass slides with 0....

Abstract: It is presently unclear why there is a high prevalence of periodontal disease (PD) in individuals living with chronic kidney disease (CKD). By employing three different models in rats and mice, we demonstrate that experimental uremia causes periodontal bone loss. Uremia alters the biochemical composition of saliva and induces progressive dysbiosis of the oral microbiota, with microbial samples from uremic animals displaying reduced overall bacterial growth, increased alpha diversity, reduced abundance of key components of the healthy oral microbiota such as Streptococcus and Rothia, and an increase in minor taxa including those from gram-negative phyla Proteobacteria and Bacteroidetes....

Abstract: Many x-ray microtomography.(XMT) studies of human vertebral bone samples have been conducted, but none with high quality, high contrast resolution methodology, which necessarily requires long integration times and, therefore, stable samples. We accessed a collection of 69 ~2mm thick, parasagittal sections of L2 vertebral bodies which were preserved - by embedding in PMMA - under the aegis of the BioMed 1 European project [Bone quality in osteoporosis]. Prior studies using quantitative backscattered electron [qBSE-SEM] imaging had shown a wide spread of local mineralisation density values when sampled at one cubic micrometer [1 fl] resolution, but only in 2D section planes....

Abstract: In linearly polarised light (LPL), birefringent structures appear brightest if they lie both in the plane of the section and at 45° / 135° to the axes of the crossed polarising filter elements, but dark if perpendicular to the section plane or parallel to either polarizer or analyser, preventing measurement of the whole scene at once because nothing can be resolved in the dark sectors of the ‘Maltese cross’. This may be solved using circularly polarised light (CPL), when dip with respect to the section-plane may be quantified for plane parallel sections and we can use pseudocolour to produce dip maps....

Abstract: Abstract for poster P25 presented at Bone Research Society, Winchester 28/6/2018 All that fractures is not bone: microscopic anatomy of vertebral bodies. Objectives: To understand interface between cortical shell and cancellous bone in human vertebral bodies, age changes, and probable mechanical significance. Archival material, 3-4 mm mid-body vertical slices, 80 L2 embedded PMMA: blocks polished, carbon coated, 20 kV qBSE SEM; high contrast resolution x-ray microtomography (XMT: 44 hour scans); iodine vapour staining and further BSE SEM, uncoated....

Abstract: Purpose: Cracks in bone and articular calcified cartilage (ACC) of the subchondral plate heal by intercalation of a highly mineralised infill material which disappears with demineralisation. This material may also extruded into hyaline articular cartilage (HAC) as High Density Mineralised Protrusions (HDMPs), which may fragment and act as a cutting and grinding agent, damaging HAC from within. We wish to know more about the structure and composition of HDMPs. We have prepared very thin sections from the front face of bone blocks embedded in PMMA - which had previously been studied by backscattered electron scanning electron microscopy (BSE-SEM) and x-ray microtomography (XMT) - by the new technique of laser-ablation machining and wanted to know if this method could be applied to this rather intractable problem....

Abstract: Fracture of nickel-titanium (NiTi) endodontic files is an uncommon but potentially damaging occurrence during root canal preparation. If the broken portion of the file remains inside the tooth canal it can prevent complete preparation of the root canal with consequent negative impact on treatment outcomes. Removal of file fragment from the tooth canal is currently a mechanical process, which due to the limited working space and restricted view can lead to further problems including perforation of the tooth....