Applying synthetic radiography to intraoral tomosynthesis: a step towards achieving 3D imaging in the dental clinic

Objectives:A practical approach to three-dimensional (3D) intraoral imaging would have many potential applications in clinical dentistry. Stationary intraoral tomosynthesis (sIOT) is an experimental 3D imaging technology that holds promise. The purpose of this study was to explore synthetic radiography as a tool to improve the clinical utility of the images generated by an sIOT scan.Methods:Extracted tooth specimens containing either caries adjacent to restorations (CAR) or vertical root fractures (VRF) were imaged by sIOT and standard dental radiography devices. Qualitative assessments were used to compare the conspicuity of these pathologies in the standard radiographs and in a set of multi-view synthetic radiographs generated from the information collected by sIOT.Results:The sIOT-based synthetic 2D radiographs contained less artefact than the image slices in the reconstructed 3D stack, which is the conventional approach to displaying information from a tomosynthesis scan. As a single sIOT scan can be used to generate synthetic radiographs from multiple viewing angles, the interproximal space was less likely to be obscured in the synthetic images compared to the standard radiograph. Additionally, the multi-view synthetic radiographs can potentially improve the display of CAR and VRFs as compared to a single standard radiograph.Conclusions:This preliminary experience combining synthetic radiography and sIOT in extracted tooth models is encouraging and supports the ongoing study of this promising approach to 3D intraoral imaging with many potential applications.     

Design and Fabrication of an Injection Tool for Neuromuscular Microstimulators

The injection of small implants into precisely localized sites within the body is a difficult task usually undertaken by surgeons or interventive radiologists. We have designed, produced and tested a simple tool for implanting BION™ wireless microstimulators as an outpatient office procedure. The ability of BIONs to elicit a desired muscle contraction depends on their placement near the motor fibers that innervate the muscle fibers, providing both the requirement and a means for achieving accurate placement. The implant is preloaded into the tip of the cannula of a two-piece insertion tool made from non-conductive polymers. Trial stimulation pulses are generated by the implant as the tool is manipulated into the desired position. The implant is released by withdrawing the cannula over the implant, preserving both the relative location of the implant’s electrodes with respect to the target and determining its desired axial orientation, which is important for implants containing motion sensors. The BION Insertion Tool has been used for over 30 BION implants in human subjects to date. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

SOCS1 deficiency results in accelerated mammary gland development and rescues lactation in prolactin receptor–deficient mice

Prolactin is essential for proliferation and differentiation of the developing mammary gland. We have explored a role for Suppressor of Cytokine Signaling 1 (SOCS1) as a modulator of the prolactin response using mice deficient in SOCS1, which were rescued from neonatal death by deletion of the Interferon gamma (IFN gamma) gene. SOCS1(-/-)/IFN gamma(-/-) mice exhibited accelerated lobuloalveolar development in the mammary gland during late pregnancy and precocious lactation. Significantly, the lactogenic defect in prolactin receptor heterozygous females could be rescued by deletion of a single SOCS1 allele. These findings establish a role for SOCS1 as a negative regulator of prolactin signaling and suggest that SOCS1 is required for the prevention of lactation prior to parturition.