Miniplate osteosynthesis for fractures of the edentulous mandible: A clinical study 1989–96

Our 8 years experience of treating fractures of the edentulous mandible by miniplate osteosynthesis, is discussed. Forty patients (31 men and 9 women) aged 37 to 86 years (mean: 64.6 years, SD: ± 14.07) with 67 fracture sites were treated. The surgical approach was mainly intraoral (37 out of 40 patients) without the use of intermaxillary fixation. The postoperative clinical and radiological findings are reported and discussed.The advantages of the method are of great importance since immediate postoperative opening of the mouth is permitted, as the fractured bones are anatomically stabilized by means of titanium miniplates and screws. Our results were felt to be satisfactory, with a reoperation rate of only 3.9% (two out of 51 operated fracture sites, 16 condylar fractures were treated conservatively). This allows us to propose intraoral miniplate osteosynthesis as a routine method of treatment in cases of edentulous mandibular fractures which are mainly seen in elderly people.     

Spectrophotometric analysis of crown discoloration induced by MTA- and ZnOE-based sealers

Crown discoloration can be induced by root canal sealer remnants following root canal treatment.

Objective:

The aim of this study was to evaluate chromatic alterations in human tooth crowns induced by a Mineral Trioxide Aggregate-based sealer (MTA Fillapex^® and a commonly used ZnOE-based sealer (Roth-811). The tested null hypothesis was that the application of the materials did not induce clinically perceptible crown discoloration (Ho: CIE color difference ΔE<3.7).

Material and Methods:

Forty five fully developed, intact, mandibular third molars were sectioned 1 mm below the cemento-enamel junction. The pulp chambers were chemomechanically debrided via the cervical access. The specimens were randomly assigned into three groups Group 1: MTA Fillapex, Group 2: Roth 811, Group 3: Negative control (unfilled) and immersed in individually marked vials containing distilled water up to the cervix (37±1º C). The spectral reflectance lines were recorded by utilizing a UV-VIS spectrophotometer equipped with integration sphere in the visual spectrum at baseline, 1 week, 1 and 3 months after material placement. Data were transformed into values of the CIE L*a*b* color system and the corresponding ΔE values were calculated. Statistical analysis was performed using two-way mixed ANOVA models, at p=0.05 level of significance.

Results:

A statistically significant increase in a* and b* chromatic parameters of the MTA Fillapex Group was measured. However, ΔE values did not exceed the human eye perceptibility threshold (set at ΔE<3.7) during the experimental period (ΔEt3=2.88). In Roth-811 Group, a statistically significant decrease in L* and a statistically significant increase in a* and b* chromatic parameters was measured, during all observation periods. Resultant ΔE values exceeded the human eye perceptibility threshold after 1 week (ΔEt1=5.65).

Conclusions:

Application of MTA Fillapex in tooth crowns resulted in minimal color alterations, while Roth 811 induced severe discoloration, in vitro. It could be suggested that, in terms of aesthetics, the use of MTA Fillapex appears to be favorable.     

Large olfactory neuroblastoma (esthesioneuroblastoma) surgically treated with an Altemir technique modification: a case report

Introduction

Olfactory neuroblastomas are rare malignant tumors that usually occur in the upper nasal cavity. The purpose of this paper is to present a case of a large olfactory neuroblastoma filling the entire nasal cavity, treated with an Altemir technique modification.

Methods

A 39-year-old woman presented with a large tumor of the nasal cavity. After the laboratory examinations, the tumor was classified as a Kadish stage A olfactory neuroblastoma. The selected treatment was the surgical excision after an Altemir technique modification combined with midfacial degloving and additional radiotherapy.

Results

Histopathology revealed a Hyams grade III olfactory neuroblastoma completely removed. Although the patient refused the additional radiotherapy, 18 months postoperatively, there were no signs of recurrence, and the patient shows big improvement on her sense of smell.

Conclusions

Large olfactory neuroblastomas filling the entire nasal cavity extending back to the postnasal space can be completely removed using a transfacial approach as the Altemir technique modification is.     

Intoxicated person discrimination using infrared signature of facial blood vessels

In this work, facial thermal infrared images are employed for intoxicated person discrimination. The activity of the facial blood vessels of sober and intoxicated people comes into sight when nonlinear anisotropic diffusion and top-hat transformation are applied to enhance and isolate the vessels from the rest of the information on the face. For an intoxicated person, vessels around the nose and eyes as well as on the forehead become more active, whereas for a person who is sober the vessels’ activity is smoother all over the face’s thermal image. Accordingly, drunkenness can be ascertained by only using the thermal infrared image of the intoxicated person. The proposed method can be incorporated into a non-invasive inspection system used by the police as a first step for intoxicated person detection. The Student’s t-test is employed to assess the degree of confidence in separating the thermal images corresponding to sober and intoxicated people. The 40 participants in the experiment have contributed to the creation of the unique sober–drunk database available on the web.     

Delayed fracture of a zirconium head after total hip arthroplasty

We present a case of fracture of a zirconium head after a cemented total hip arthroplasty. The fracture occurred 81 months after the index operation without any history of trauma. The patient was thin, not participating in sports, and the zirconium head had 0-mm neck length. Preoperative radiographs demonstrated aseptic loosening of both components and significant polyethylene wear. Fracture pattern was unusual as the major fragment was half of the head. A revision was performed to a cementless arthroplasty. The authors have obtained the patient's informed written consent for print and electronic publication of the case report.     

Structurally defined signaling in neuro-glia units in the enteric nervous system

Coordination of gastrointestinal function relies on joint efforts of enteric neurons and glia, whose crosstalk is vital for the integration of their activity. To investigate the signaling mechanisms and to delineate the spatial aspects of enteric neuron-to-glia communication within enteric ganglia we developed a method to stimulate single enteric neurons while monitoring the activity of neighboring enteric glial cells. We combined cytosolic calcium uncaging of individual enteric neurons with calcium imaging of enteric glial cells expressing a genetically encoded calcium indicator and demonstrate that enteric neurons signal to enteric glial cells through pannexins using paracrine purinergic pathways. Sparse labeling of enteric neurons and high-resolution analysis of the structural relation between neuronal cell bodies, varicose release sites and enteric glia uncovered that this form of neuron-to-glia communication is contained between the cell body of an enteric neuron and its surrounding enteric glial cells. Our results reveal the spatial and functional foundation of neuro-glia units as an operational cellular assembly in the enteric nervous system.     

A neural network model of Parkinson's disease bradykinesia.

Parkinson's disease (PD) is caused by dopamine (DA) depletion consequent to cell degeneration in the substantia nigra pars compacta (SNc) and the ventral tegmental area (VTA). Although computational analyses of PD have focused on DA depletion in DA-recipient parts of the basal ganglia, there is also extensive DAergic innervation of the frontal and parietal cortex as well as the spinal cord. To understand PD bradykinesia, a comprehensive network model is needed to study how patterns of DA depletion at key cellular sites in the basal ganglia, cortex and spinal cord contribute to disordered neuronal and spinal cord activity and other PD symptoms. We extend a basal ganglia-cortico-spinal circuit for control of voluntary arm movements by incorporating DAergic innervation of cells in the cortical and spinal components of the circuit. The resultant model simulates successfully several of the main reported effects of DA depletion on neuronal, electromyographic (EMG), and movement parameters of PD bradykinesia.     

Effect of chronic exercise on DNA fragmentation and on lipid profiles in rat skeletal muscle

The concentration and fatty acid composition of phospholipids in animal cells are important determinants of membrane function. Membrane function may influence apoptosis, a biological process that is crucial for the normal development and function of the body. Few and conflicting data exist regarding the effect of chronic exercise on apoptosis in skeletal muscle, and no data exist regarding the effect of chronic exercise on the fatty acid composition of individual muscle phospholipids. We therefore examined the effects of 8 weeks of voluntary wheel running on DNA fragmentation (an index of apoptosis) and on the concentration and fatty acid composition of individual muscle phospholipids and ceramide (a lipid involved in apoptotic signalling) in rat gastrocnemius muscle by comparing 11 trained and 14 untrained male Wistar rats. The trained animals had significantly ( P < 0.05) higher cytochrome c oxidase activity (an index of aerobic adaptation) and lower phosphatidyl inositol concentration compared with their untrained counterparts. Groups did not differ in DNA fragmentation or any other lipid parameter. Our findings suggest that chronic wheel running did not affect apoptosis or the concentration and fatty acid composition of most phospholipids and ceramide in rat gastrocnemius muscle. Given the participation of several phospholipids and ceramide in apoptotic signalling, it appears that the lack of changes in the lipid parameters is in agreement with the lack of change in DNA fragmentation with exercise.