Prevalence and Anatomical Characteristics of Bifid and Trifid Mandibular Canals: A Computer Tomography Analysis.

PURPOSE: To assess the prevalence and configuration of bifid (BMC) and trifid (TMC) mandibular canals using computed tomography (CT), describing the anatomical characteristics of the accessory canals, especially of the retromolar type. MATERIALS AND METHODS: CT scans of 123 patients were analysed. BMCs were identified and the patterns of bifurcation were classified, including trifid canals. The width of accessory canals was measured. Retromolar canals were further classified according to their course and morphology, while their position and width were evaluated using linear measurements on CT images. RESULTS: The majority of patients (53.6%) presented at least one BMC or TMC. 36.2% of mandibular canals were bifid, while 4.5% were trifid. The forward canals (12.6%) and retromolar canals (10.2%) were the most common among BMCs. In relation to the retromolar canals, 60% were vertical and 40% curved, with a mean width of 1.03 ± 0.28mm. CONCLUSION: BMCs and TMCs are common 3D radiographic findings, so that they should be considered as anatomical variations, not anomalies. Preoperative CT or CBCT evaluation should aid in identifying these variations and analysing their position and course in surgical planning.

A challenging diagnosis of late-onset tumefactive multiple sclerosis associated to cervicodorsal syringomyelia: doubtful CT, MRI, and bioptic findings: Case report and literature review.

BACKGROUND: Tumefactive multiple sclerosis (MS) is an unusual variant of demyelinating disease characterized by lesions with pseudotumoral appearance on radiological imaging mimicking other space-occupying lesions, such as neoplasms, infections, and infarction. Especially when the patient's medical history is incompatible with MS, the differential diagnosis between these lesions constitutes a diagnostic challenge often requiring histological investigation. An older age at onset makes distinguishing tumefactive demyelinating lesion (TDL) from tumors even more challenging. METHODS: We report a case of brain TDL as the initial manifestation of late-onset MS associated with cervico-dorsal syringomyelia. A 66-year-old Caucasian woman with a 15-day history headache was referred to our hospital because of the acute onset of paraphasia. She suffered from noncommunicating syringomyelia associated to basilar impression and she reported a 10-year history of burning dysesthesia of the left side of the chest extended to the internipple line level. RESULTS: Computed tomography (CT) and magnetic resonance imaging (MRI) examinations revealed a left frontal lesion with features suspicious for a tumor. Given the degree of overlap with other pathologic processes, CT and MRI findings failed to provide an unambiguous diagnosis; furthermore, because of the negative cerebrospinal fluid analysis for oligoclonal bands, the absence of other lesions, and the heightened suspicion of neoplasia, the clinicians opted to perform a stereotactic biopsy. Brain specimen analysis did not exclude the possibility of perilesional reactive gliosis and the patient, receiving anitiedemigen therapy, was monthly followed up. In the meanwhile, the second histological opinion of the brain specimen described the absence of pleomorphic glial cells indicating a tumor. These findings were interpreted as destructive inflammatory demyelinating disease and according to the evolution of MRI lesion burden, MS was diagnosed. CONCLUSION: TDL still remains a problematic entity clinically, radiologically, and sometimes even pathologically. A staged follow-up is necessary, and in our case, it revealed to be the most important attitude to define the nature of the lesion, confirming the classic MS diagnostic criteria of disseminate lesions in time and space. We discuss our findings according to the recent literature.

Clinical evaluation of 209 all-ceramic single crowns cemented on natural and implant-supported abutments with different luting agents: a 6-year retrospective study.

BACKGROUND: The Procera AllCeram™ system (Nobel Biocare AB, Göteborg, Sweden) is a valid alternative to metal-ceramic restorations. However, limited long-term data of its use for single crowns on natural and implant-supported abutments are available. PURPOSE: The present study aimed at evaluating the clinical performances of Procera AllCeram single crowns in both anterior and posterior regions of the oral cavity either on natural tooth or implant abutments over a period of 6 years. MATERIALS AND METHODS: Two hundred nine single crowns were fabricated and used in 112 patients. Zinc phosphate and resin luting agents were used to cement the restorations. The crowns were evaluated according to the California Dental Association's quality assessment system. RESULTS: Three crowns were lost at follow-up. Of the 206 restorations, which completed the 6-year follow-up, 9 crowns were affected by mechanical complications and 7 crowns failed. All surviving crowns were ranked as either excellent or acceptable. Cumulative survival and success rates of 95.2 and 90.9%, respectively, were recorded. CONCLUSIONS: Within the limitations of the present study, Procera AllCeram crowns proved to be a reliable clinical option to restore both anterior and posterior missing teeth either on natural or implant abutments. The resin cement used in the present study performed better than the zinc phosphate luting agent.

Novel design of drug delivery in stented arteries: a numerical comparative study.

Implantation of drug eluting stents following percutaneous transluminal angioplasty has revealed a well established technique for treating occlusions caused by the atherosclerotic plaque. However, due to the risk of vascular re-occlusion, other alternative therapeutic strategies of drug delivery are currently being investigated. Polymeric endoluminal pave stenting is an emerging technology for preventing blood erosion and for optimizing drug release. The classical and novel methodologies are compared through a mathematical model able to predict the evolution of the drug concentration in a cross-section of the wall. Though limited to an idealized configuration, the present model is shown to catch most of the relevant aspects of the drug dynamics in a delivery system. Results of numerical simulations shows that a bi-layer gel paved stenting guarantees a uniform drug elution and a prolonged perfusion of the tissues, and remains a promising and effective technique in drug delivery.

Ruptured, dissecting posterior inferior cerebellar artery aneurysms: endovascular treatment without parent vessel occlusion.

INTRODUCTION: Treatment of a dissecting aneurysm of the medullary segments of the posterior inferior cerebellar artery (PICA) usually entails trapping of the diseased arterial segment with possible sacrifice of brainstem perforators. The goal of the work was to review our experience with selective coiling of ruptured, dissecting aneurysms of the anterolateral segments of the PICA without parent vessel occlusion. METHODS: Eleven consecutive patients (9 women, 2 men, mean age 47.2 years) were retrospectively reviewed from a prospectively acquired neuroradiological database. On admission three patients had Hunt and Hess (HH) grade I, three HH grade II, two HH grade III, and one HH grade IV. Outcome was evaluated according to the modified Rankin scale (mRS) score. Follow-up (mean:19.4 months) consisted of magnetic resonance angiography and/or digital subtraction angiography in ten patients. RESULTS: Ten patients had mRS score 0 and one mRS score 2. No treatment failure occurred. The aneurysm was completely occluded in seven patients, a neck residue was present in two, and a loose coil mesh was present in two. Recurrence occurred in three patients, and all were successfully retreated for a total of 13 procedures. Procedure-related complications were all without clinical consequences and included a coil perforation in one procedure and stagnant filling of the parent vessel in six procedures. PICA occlusion did not occur in any patient. CONCLUSION: Coiling of ruptured, isolated dissecting aneurysms of the PICA without parent vessel occlusion is feasible, relatively safe and effective in preventing early/medium-term rebleeding. A strict angiographic follow-up program is, however, necessary to detect recurrence.

Endovascular treatment of painless aortic ulcer detected by transesophageal echocardiography as an incidental finding.

Penetrating aortic ulcer (PAU) is defined as an ulcerating atherosclerotic lesion that disrupts the aortic wall layers, penetrating the internal elastic lamina. The natural history of the disease and the preferred treatment are still debated. We report a case of painless PAU in a 78-year-old man detected by transesophageal echocardiography at the level of proximal descending aorta as an incidental finding. The patient underwent endovascular stent-graft placement without any complications at early and late follow-up.