Can traumatic occlusion cause endodontic problems? A case report

Radicular cysts are commonly found odontogenic cysts in the jaws. The lesion is diagnosed mainly in young patients during the second decade of life. In the majority of cases, it is asymptomatic. This paper reports a rare case in which traumatic occlusion was identified as the etiology of a radicular cyst. Endodontic treatment was performed and the traumatic occlusion also was corrected. A six-month follow-up appointment found good healing of the periapical region.     

Root and canal morphology of Indian maxillary premolars by a modified root canal staining technique

The aim of this study was to investigate the root and canal morphology of maxillary first and second premolars in Indians by a modified canal staining and tooth clearing technique. Maxillary first (350) and second (350) premolars were collected, and the morphology and number of roots analyzed. After cleaning, the teeth were immersed in India ink and placed in a hyperbaric oxygen chamber at 0.6 MPa for 2 h. The teeth were then demineralized and cleared. Digital images of the teeth were examined under magnification to evaluate the number of root canals, root canal system configurations, number of apical foramina, and intercanal communications. Root canal configurations were identified based on Vertucci’s classification and Gulabivala’s additional classes. The most common root morphology of the first premolars was the classical two separate root morphology (a Caucasian trait) and that of the second premolars was a single-root morphology (a Mongoloid trait), though other morphologies such as singlerooted first premolars and three-rooted first and second premolars were also identified. A “radiculous” first premolar was identified in two samples. The buccal roots of the first premolar showed the maximum variation, the most common being type I (Vertucci’s classification), followed by type IV. The highest incidence of intercanal communications was found in the single-rooted first premolars. All roots exhibiting type IV and V canal configurations showed two separate apical foramina, while additional type 2–3 canal configurations showed three separate apical foramina. The root number and morphology as well as the canal morphology of Indian maxillary premolars showed both Mongolian and Caucasian traits.     

Melorheostosis causing lumbar radiculopathy: a case report and a review of the literature

Background contextMelorheostosis is a rare sclerosing bone disorder with a predilection for the appendicular skeleton. Involvement of the spine is infrequent and largely asymptomatic. Surgical treatment for spinal involvement is therefore uncommon with only one reported case of lumbar fusion for painful lumbosacral melorheostosis.PurposeWe report a case of lumbar melorheostosis causing disabling radiculopathy treated with nerve root decompression.ConclusionsMelorheostosis of the lumbar spine causing radicular symptoms has not been reported before. Our message from the management of this particular patient is to consider surgical option in symptomatic individuals.     

Micro Particle Image Velocimetry Measurements of Steady Diastolic Leakage Flow in the Hinge of a St. Jude Medical® Regent™ Mechanical Heart Valve

A number of clinical, in vitro and computational studies have shown the potential for thromboembolic complications in bileaflet mechanical heart valves (BMHV), primarily due to the complex and unsteady flows in the valve hinges. These studies have focused on quantitative and qualitative parameters such as velocity magnitude, turbulent shear stresses, vortex formation, and platelet activation to identify potential for blood damage. However, experimental characterization of the whole flow fields within the valve hinges has not yet been conducted. This information can be utilized to investigate instantaneous damage to blood elements and also to validate numerical studies focusing on the hinge’s complex fluid dynamics. The objective of this study was therefore to develop a high-resolution imaging system to characterize the flow fields and global velocity maps in a BMHV hinge. In this study, the steady leakage hinge flow fields representing the diastolic phase during the cardiac cycle in a 23 mm St. Jude Medical regent BMHV in the aortic position were characterized using a two-dimensional micro particle image velocimetry system. Diastolic flow was simulated by imposing a static pressure head on the aortic side. Under these conditions, a reverse flow jet from the aortic to the ventricular side was observed with velocities in the range of 1.47–3.24 m/s, whereas low flow regions were observed on the ventricular side of the hinge with viscous shear stress magnitude up to 60 N/m². High velocities and viscous shearing may be associated with platelet activation and hemolysis, while low flow zones can cause thrombosis due to increased residence time in the hinge. Overall, this study provides a high spatial resolution experimental technique to map the fluid velocity in the BMHV hinge, which can be extended to investigate micron-scale flow domains in various prosthetic devices under different hemodynamic conditions.     

An In Vitro Evaluation of the Impact of Eccentric Deployment on Transcatheter Aortic Valve Hemodynamics

Patients with aortic stenosis present with calcium deposits on the native aortic valve, which can result in non-concentric expansion of Transcatheter Aortic Valve Replacement (TAVR) stents. The objective of this study is to evaluate whether eccentric deployment of TAVRs lead to turbulent blood flow and blood cell damage. Particle Image Velocimetry was used to quantitatively characterize fluid velocity fields, shear stress and turbulent kinetic energy downstream of TAVRs deployed in circular and eccentric orifices representative of deployed TAVRs in vivo. Effective orifice area (EOA) and mean transvalvular pressure gradient (TVG) values did not differ substantially in circular and eccentric deployed valves, with only a minor decrease in EOA observed in the eccentric valve (2.0 cm² for circular, 1.9 cm² for eccentric). Eccentric deployed TAVR lead to asymmetric systolic jet formation, with increased shear stresses (circular = 97 N/m² vs. eccentric = 119 N/m²) and regions of turbulence intensity (circular = 180 N/m² vs. eccentric = 230 N/m²) downstream that was not present in the circular deployed TAVR. The results of this study indicate that eccentric deployment of TAVRs can lead to altered flow characteristics and may potentially increase the hemolytic potential of the valve, which were not captured through hemodynamic evaluation alone.     

The NF-kappaB subunit Rel A is associated with in vitro survival and clinical disease progression in chronic lymphocytic leukemia and represents a promising therapeutic target

In this study, we characterized nuclear factor B (NF-B) subunit DNA binding in chronic lymphocytic leukemia (CLL) samples and demonstrated heterogeneity in basal and inducible NF-B. However, all cases showed higher basal NF-B than normal B cells. Subunit analysis revealed DNA binding of p50, Rel A, and c-Rel in primary CLL cells, and Rel A DNA binding was associated with in vitro survival (P = .01) with high white cell count (P = .01) and shorter lymphocyte doubling time (P = .01). NF-B induction after in vitro stimulation with anti-IgM was associated with increased in vitro survival (P < .001) and expression of the signaling molecule ZAP-70 (P = .003). Prompted by these data, we evaluated the novel parthenolide analog, LC-1, in 54 CLL patient samples. LC-1 induced apoptosis in all the samples tested with a mean LD₅₀ of 2.8 µM after 24 hours; normal B and T cells were significantly more resistant to its apoptotic effects (P < .001). Apoptosis was preceded by a marked loss of NF-B DNA binding and sensitivity to LC-1 correlated with basal Rel A DNA binding (P = .03, r² = 0.15). Furthermore, Rel A DNA binding was inversely correlated with sensitivity to fludarabine (P = .001, r² = 0.3), implicating Rel A in fludarabine resistance. Taken together, these data indicate that Rel A represents an excellent therapeutic target for this incurable disease.     

Root fillings with a matched-taper single cone and two calcium silicate–based sealers: an analysis of voids using micro-computed tomography

Clinical Oral Investigations - To compare the percentage of voids in matched-taper single-cone fillings with GuttaFlow Bioseal or BioRoot RCS root canal sealers, using micro-computed tomography....