Complications liées aux piercings [Complications of body piercing].

Au sein de la population générale, de plus en plus de personnes arborent des piercings, en particulier parmi les jeunes adultes. Hormis les réactions inflammatoires et les infections locales, les complications liées à ces piercings sont méconnues. Les personnes ne sont en général pas informées des risques avant de réaliser un piercing et leurs antécédents, traitements médicamenteux ou comorbidités éventuelles, sont largement négligés par les personnes qui réalisent le geste. Les complications sont le plus souvent locales et bénignes, mais des complications sérieuses et parfois mortelles ont été décrites dans la littérature. Cet article propose une revue des problématiques possibles auxquelles pourrait être confronté un médecin de premier recours, face à un patient qui souhaiterait réaliser un piercing ou présenterait des complications suite à la mise en place d'un tel dispositif. The trend of body piercing has grown in popularity in the past decade within the general population and especially among young adults. Complications of body piercing include local inflammation and infections, but severe complications are also possible and largely underestimated. People are usually not aware of the risks before making a piercing, and their medical history, medication and comorbidities are largely neglected by the people who realise the piercing. This article presents a review of the complications that a primary care physician may observe, for a patient who wishes to make a piercing, or presents complications due to the implementation of such a device.

Comparison between Radiographic (2-dimensional and 3-dimensional) and Histologic Findings of Periapical Lesions Treated with Apical Surgery.

INTRODUCTION: The aim of this study was to evaluate the concordance of 2- and 3-dimensional radiography and histopathology in the diagnosis of periapical lesions. METHODS: Patients were consecutively enrolled in this study provided that preoperative periapical radiography (PR) and cone-beam computed tomographic imaging of the tooth to be treated with apical surgery were performed. The periapical lesional tissue was histologically analyzed by 2 blinded examiners. The final histologic diagnosis was compared with the radiographic assessments of 4 blinded observers. The initial study material included 62 teeth in the same number of patients. RESULTS: Four lesions had to be excluded during processing, resulting in a final number of 58 evaluated cases (31 women and 27 men, mean age = 55 years). The final histologic diagnosis of the periapical lesions included 55 granulomas (94.8%) and 3 cysts (5.2%). Histologic analysis of the tissue samples from the apical lesions exhibited an almost perfect agreement between the 2 experienced investigators with an overall agreement of 94.83% (kappa = 0.8011). Radiographic assessment overestimated cysts by 28.4% (cone-beam computed tomographic imaging) and 20.7% (periapical radiography), respectively. Comparing the correlation of the radiographic diagnosis of 4 observers with the final histologic diagnosis, 2-dimensional (kappa = 0.104) and 3-dimensional imaging (kappa = 0.111) provided only minimum agreement. CONCLUSIONS: To establish a final diagnosis of an apical radiolucency, the tissue specimen should be evaluated histologically and specified as a granuloma (with/without epithelium) or a cyst. Analysis of 2-dimensional and 3-dimensional radiographic images alike results only in a tentative diagnosis that should be confirmed with biopsy.

Multilayered organization of jasmonate signalling in the regulation of root growth.

Physical damage can strongly affect plant growth, reducing the biomass of developing organs situated at a distance from wounds. These effects, previously studied in leaves, require the activation of jasmonate (JA) signalling. Using a novel assay involving repetitive cotyledon wounding in Arabidopsis seedlings, we uncovered a function of JA in suppressing cell division and elongation in roots. Regulatory JA signalling components were then manipulated to delineate their relative impacts on root growth. The new transcription factor mutant myc2-322B was isolated. In vitro transcription assays and whole-plant approaches revealed that myc2-322B is a dosage-dependent gain-of-function mutant that can amplify JA growth responses. Moreover, myc2-322B displayed extreme hypersensitivity to JA that totally suppressed root elongation. The mutation weakly reduced root growth in undamaged plants but, when the upstream negative regulator NINJA was genetically removed, myc2-322B powerfully repressed root growth through its effects on cell division and cell elongation. Furthermore, in a JA-deficient mutant background, ninja1 myc2-322B still repressed root elongation, indicating that it is possible to generate JA-responses in the absence of JA. We show that NINJA forms a broadly expressed regulatory layer that is required to inhibit JA signalling in the apex of roots grown under basal conditions. By contrast, MYC2, MYC3 and MYC4 displayed cell layer-specific localisations and MYC3 and MYC4 were expressed in mutually exclusive regions. In nature, growing roots are likely subjected to constant mechanical stress during soil penetration that could lead to JA production and subsequent detrimental effects on growth. Our data reveal how distinct negative regulatory layers, including both NINJA-dependent and -independent mechanisms, restrain JA responses to allow normal root growth. Mechanistic insights from this work underline the importance of mapping JA signalling components to specific cell types in order to understand and potentially engineer the growth reduction that follows physical damage.

SEM evidence for existence of an apical disc on the scolex of Clestobothrium crassiceps (Rudolphi, 1819): comparative results of various fixation techniques

The scolex of the bothriocephalidean cestode Clestobothrium crassiceps was studied by means of scanning electron microscopy (SEM). The comparative results of various fixation procedures and techniques are presented. The scolex of C. crassiceps is oval to globular and exhibits two deep bothria which appear in the form of two lobes separated by a longitudinal groove. At the apex of the scolex, resembling a beret, an apical disc is present (oval, flattened and with a sinuous edge). Our results are compared with those previously reported in other species of Clestobothrium. This study represents the first report which highlights the presence of an apical disc in the scolex of C. crassiceps. It describes the effects of different procedures applied to our material during preparation and a comparative analysis results obtained using these various methods.

SEM evidence for existence of an apical disc on the scolex of Clestobothrium crassiceps (Rudolphi, 1819): comparative results of various fixation techniques

The scolex of the bothriocephalidean cestode Clestobothrium crassiceps was studied by means of scanning electron microscopy (SEM). The comparative results of various fixation procedures and techniques are presented. The scolex of C. crassiceps is oval to globular and exhibits two deep bothria which appear in the form of two lobes separated by a longitudinal groove. At the apex of the scolex, resembling a beret, an apical disc is present (oval, flattened and with a sinuous edge). Our results are compared with those previously reported in other species of Clestobothrium. This study represents the first report which highlights the presence of an apical disc in the scolex of C. crassiceps. It describes the effects of different procedures applied to our material during preparation and a comparative analysis results obtained using these various methods.

Sox4 participates in the modulation of Schwann cell myelination.

In order to identify new regulators of Schwann cell myelination potentially playing a role in peripheral nervous system (PNS) pathologies, we analysed gene expression profiling data from three mouse models of demyelinating neuropathies and from the developing PNS. This analysis revealed that Sox4, which encodes a member of the Sry-related high-mobility group box protein family, was consistently upregulated in all three analysed models of neuropathy. Moreover, Sox4 showed a peak in its expression during development that corresponded with the onset of myelination. To gain further insights into the role of Sox4 in PNS development, we generated a transgenic mouse that specifically overexpresses Sox4 in Schwann cells. Sox4 overexpression led to a temporary delay in PNS myelination without affecting axonal sorting. Importantly, we observed that, whereas Sox4 mRNA could be efficiently overexpressed, Sox4 protein expression in Schwann cells was strictly regulated. Finally, our data showed that enforced expression of Sox4 in the mouse model for Charcot-Marie-Tooth 4C aggravated its neuropathic phenotype. Together, these observations reveal that Sox4 contributes to the regulation of Schwann cell myelination, and also indicates its involvement in the pathophysiology of peripheral neuropathies.

THE LYCHEE TREE PROPAGATION BY LAYERING

The aim of the study was to assess the influence of season and different substrates on rooting of air layers of lychee (Litchi chinensisSonn.) for the production of seedlings to ensure the formation of uniform and productive orchards. Air layers were done in plants of the Bengal cultivar using leafy and healthy woody branches, with about 0.010 to 0.015 m in diameter, in which were performed complete girdling with 0.020 m wide at a distance of 0.30 to 0.40 m below the apex. Then the branches were wrapped in moistened substrate. The layering was made at six times of theyear (January, March, May, July, September and November) and two substrates were used (coconut fiber and sphagnum) in a 6 x 2 factorial design in a randomized block with ten replicates. After 90 days, layers were separated from the matrix plant and evaluated for rooting and callus formation, root number, considering only the primary roots, length, area and volume of the roots, beyond the dry weight of roots and calluses. The months of January, March, September and November showed the best results for all analyzed variables related to rooting. With respect to the substrates, the only difference was in January and March to the root number and dry weight of roots, where the sphagnum showed the best results. The month of July was more conducive to the formation of calluses. The period between September and March was more suitable to the propagation of lychee, when there were rooting percentages above 90%, in addition to the formation of large amount of roots.

Changes of Root Length and Root-to-Crown Ratio after Apical Surgery: An Analysis by Using Cone-beam Computed Tomography.

INTRODUCTION: Apical surgery is an important treatment option for teeth with post-treatment periodontitis. Although apical surgery involves root-end resection, no morphometric data are yet available about root-end resection and its impact on the root-to-crown ratio (RCR). The present study assessed the length of apicectomy and calculated the loss of root length and changes of RCR after apical surgery. METHODS: In a prospective clinical study, cone-beam computed tomography scans were taken preoperatively and postoperatively. From these images, the crown and root lengths of 61 roots (54 teeth in 47 patients) were measured before and after apical surgery. Data were collected relative to the cementoenamel junction (CEJ) as well as to the crestal bone level (CBL). One observer took all measurements twice (to calculate the intraobserver variability), and the means were used for further analysis. The following parameters were assessed for all treated teeth as well as for specific tooth groups: length of root-end resection and percentage change of root length, preoperative and postoperative RCRs, and percentage change of RCR after apical surgery. RESULTS: The mean length of root-end resection was 3.58 ± 1.43 mm (relative to the CBL). This amounted to a loss of 33.2% of clinical and 26% of anatomic root length. There was an overall significant difference between the tooth groups (P < .05). There was also a statistically significant difference comparing mandibular and maxillary teeth (P < .05), but not for incisors/canines versus premolars/molars (P = .125). The mean preoperative and postoperative RCRs (relative to CEJ) were 1.83 and 1.35, respectively (P < .001). With regard to the CBL reference, the mean preoperative and postoperative RCRs were 1.08 and 0.71 (CBL), respectively (P < .001). The calculated changes of RCR after apical surgery were 24.8% relative to CEJ and 33.3% relative to CBL (P < .001). Across the different tooth groups, the mean RCR was not significantly different (P = .244 for CEJ and 0.114 for CBL). CONCLUSIONS: This CBCT-based study demonstrated that the RCR is significantly changed after root-end resection in apical surgery irrespective of the clinical (CBL) or anatomic (CEJ) reference levels. The lowest, and thus clinically most critical, postoperative RCR was observed in maxillary incisors. Future clinical studies need to show the impact of resection length and RCR changes on the outcome of apical surgery.

Cardan Gear Mechanism versus Slider-Crank Mechanism in Pumps and Engines

In machine design we always want to save space, save energy and produce as much power as possible. We can often reduce accelerations, inertial loads and energy consumption by changing construction. In this study the old cardan gear mechanism (hypocycloid mechanism) has been compared with the conventional slider-crank mechanism in air pumps and four-stroke engines. Comprehensive Newtonian dynamics has been derived for the both mechanisms. First the slidercrank and the cardan gear machines have been studied as lossless systems. Then the friction losses have been added to the calculations. The calculation results show that the cardan gear machines can be more efficient than the slider-crank machines. The smooth running, low mass inertia, high pressures and small frictional power losses make the cardan gear machines clearly better than the slider-crank machines. The dynamic tooth loads of the original cardan gear construction do not rise very high when the tooth clearances are kept tight. On the other hand the half-size crank length causes high bearing forces in the cardan gear machines. The friction losses of the cardan gear machines are generally quite small. The mechanical efficiencies are much higher in the cardan gear machines than in the slider-crank machines in normal use. Crankshaft torques and power needs are smaller in the cardan gear air pumps than in the equal slider-crank air pumps. The mean crankshaft torque and the mean output power are higher in the cardan gear four-stroke engines than in the slider-crank four-stroke engines in normal use. The cardan gear mechanism is at its best, when we want to build a pump or an engine with a long connecting rod (≈ 5⋅crank length) and a thin piston (≈ 1.5⋅crank length) rotating at high angular velocity and intermittently high angular acceleration. The cardan gear machines can be designed also as slide constructions without gears. Suitable applications of the cardan gear machines are three-cylinder half-radial engines for motorcycles, sixcylinder radial engines for airplanes and six-cylinder double half-radial engines for sport cars. The applied equations of Newtonian dynamics, comparative calculations, calculation results (tables, curves and surface plots) and recommendations presented in this study hold novelty value and are unpublished before. They have been made and written by the author first time in this study.

Pain-evoked alterations on gingival blood flow and gingival crevicular fluid (GCF) neuropeptide SP and collagenase-2 (MMP-8) levels

Previous studies have demonstrated that clinical pulpal pain can induce the expression of pro-inflammatory neuropeptides in the adjacent gingival crevice fluid (GCF). Vasoactive agents such as substance P (SP) are known to contribute to the inflammatory type of pain and are associated with increased blood flow. More recent animal studies have shown that application of capsaicin on alveolar mucosa provokes pain and neurogenic vasodilatation in the adjacent gingiva. Pain-associated inflammatory reactions may initiate expression of several pro- and anti-inflammatory mediators. Collagenase-2 (MMP-8) has been considered to be the major destructive protease, especially in the periodontitis-affected gingival crevice fluid (GCF). MMP-8 originates mostly from neutrophil leukocytes, the first line of defence cells that exist abundantly in GCF, especially in inflammation. With this background, we wished to clarify the spatial extensions and differences between tooth-pain stimulation and capsaicin-induced neurogenic vasodilatation in human gingiva. Experiments were carried out to study whether tooth stimulation and capsaicin stimulation of alveolar mucosa would induce changes in GCF MMP-8 levels and whether tooth stimulation would release neuropeptide SP in GCF. The experiments were carried out on healthy human volunteers. During the experiments, moderate and high intensity painful tooth stimulation was performed by a constant current tooth stimulator. Moderate tooth stimulation activates A-delta fibres, while high stimulation also activates C-fibres. Painful stimulation of the gingiva was achieved by topical application of capsaicin-moistened filter paper on the mucosal surface. Capsaicin is known to activate selectively nociceptive C-fibres of stimulated tissue. Pain-evoked vasoactive changes in gingivomucosal tissues were mapped by laser Doppler imaging (LDI), which is a sophisticated and non-invasive method for studying e.g. spatial and temporal characteristics of pain- and inflammation-evoked blood flow changes in gingivomucosal tissues. Pain-evoked release of MMP-8 in GCF samples was studied by immunofluorometric assay (IFMA) and Western immunoblotting. The SP levels in GCF were analysed by Enzyme immunoassay (EIA). During the experiments, subjective stimulus-evoked pain responses were determined by a visual analogue pain scale. Unilateral stimulation of alveolar mucosa and attached gingiva by capsaicin evoked a distinct neurogenic vasodilatation in the ipsilateral gingiva, which attenuated rapidly at the midline. Capsaicin stimulation of alveolar mucosa provoked clear inflammatory reactions. In contrast to capsaicin stimuli, tooth stimulation produced symmetrical vasodilatations bilaterally in the gingiva. The ipsilateral responses were significantly smaller during tooth stimulation than during capsaicin stimuli. The current finding – that tooth stimulation evokes bilateral vasodilatation while capsaicin stimulation of the gingiva mainly produces unilateral vasodilatation – emphasises the usefulness of LDI in clarifying spatial features of neurogenic vasoactive changes in the intra-oral tissues. Capsaicin stimulation of the alveolar mucosa induced significant elevations in MMP-8 levels and activation in GCF of the adjacent teeth. During the experiments, no marked changes occurred in MMP-8 levels in the GCF of distantly located teeth. Painful stimulation of the upper incisor provoked elevations in GCF MMP-8 and SP levels of the stimulated tooth. The GCF MMP-8 and SP levels of the non-stimulated teeth were not changed. These results suggest that capsaicin-induced inflammatory reactions in gingivomucosal tissues do not cross the midline in the anterior maxilla. The enhanced reaction found during stimulation of alveolar mucosa indicates that alveolar mucosa is more sensitive to chemical irritants than the attached gingiva. Analysis of these data suggests that capsaicin-evoked neurogenic inflammation in the gingiva can trigger the expression and activation of MMP-8 in GCF of the adjacent teeth. In this study, it is concluded that experimental tooth pain at C-fibre intensity can induce local elevations in MMP-8 and SP levels in GCF. Depending on the role of MMP-8 in inflammation, in addition to surrogated tissue destruction, the elevated MMP-8 in GCF may also reflect accelerated local defensive and anti-inflammatory reactions.

Analysis of the antibiotic prophylaxis prescribed by Spanish oral surgeons

Aim: To identify prophylactic antibiotic prescription practices among Spanish dentists with preferential dedication to Oral Surgery in different types of tooth extraction surgeries. Method: Members of the Spanish Oral Surgery Society were surveyed on antibiotic prophylaxis use in 4 different tooth extraction modalities scaled according to their surgical invasiveness. Results: Sixty-nine of the 105 distributed questionnaires were returned completed. Thirteen percent of the surveyed surgeons would prescribe antibiotics to prevent postoperative wound infection when confronted with conventional tooth extraction lasting less than 5 minutes. In the case of surgery lasting more than 5 minutes, the percentage of participants that would prescribe antibiotics increased to 39%. When a mucoperiosteal flap was elevated or an ostectomy was performed, 87% and 100%, respectively, would prescribe antibiotic prophylaxis. Amoxicillin and its combination with clavulanic acid were the most commonly prescribed antibiotics. All participants would prescribe the antibiotic orally, starting after surgery and with a duration that ranged from 2-8 days. Conclusions: The results obtained suggest that antibiotic prophylaxis for preventing local odontogenic infection is not being correctly implemented in Spain. This can generate new bacterial resistances, facilitate adverse drug reactions and favor opportunistic infections. Better designed studies are needed in order to clarify the role of antibiotics in the prevention of postsurgical wound infection

Complications of guided surgery and immediate loading in oral implantology: a report of 12 cases

Objectives: The growing interest in minimally invasive surgery, together with the possibility of fitting prostheses with immediate function, have led to the development of software capable of planning and manufacturing a surgical guide and prosthesis that can be placed upon conclusion of the implant surgery step. The present study evaluates the surgical and prosthetic complications of implant treatment with the guided surgery technique, together with patient comfort during and after treatment. Patients and methods: A retrospective observational study was made of 19 patients with partially or totally edentulous upper and/or lower maxillae, involving the placement of a total of 122 implants. All cases were planned and operated upon with the guided surgery technique. Results: A total of 122 implants were placed in 14 males and 5 females. The intraoperative surgical complications comprised a lack of primary stability, while the postoperative complications consisted of infections and a lack of implant osteointegration. Ten implants failed. The prosthetic complications in turn comprised loosening of the provisional prosthesis screws, prosthesis tooth fracture, and a lack of passive fit of the immediate prosthesis. The degree of patient satisfaction was evaluated using a verbal scale. Conclusions: Implant restoration with the guided surgery technique and immediate functional loading is a predictable procedure, provided patient selection and the surgical technique are adequate, affording lesser postoperative morbidity and increased patient satisfaction thanks to the immediate restoration of esthetics and function

A prospective, randomized, triple-blind comparison of articaine and bupivacaine for maxillary infiltrations

Objectives: To compare the clinical anesthetic efficacy of 0.5% bupivacaine and 4% articaine (both with 1:200.000 adrenaline) for anterior maxillary infiltration in healthy volunteers. Material and methods: A triple-blind split-mouth randomized clinical trial was carried out in 20 volunteers. A supraperiosteal buccal injection of 0.9 ml of either solution at the apex of the lateral incisor was done in 2 appointments separated 2 weeks apart. The following outcome variables were measured: latency time, anesthetic efficacy (dental pulp, keratinized gingiva, alveolar mucosa and upper lip mucosa and tissue) and the duration of anesthetic effect. Hemodynamic parameters were monitored during the procedure. Results: Latency time recorded was similar for both anesthetic solutions (p>0.05). No statistically significant differences were found in terms of anesthetic efficacy for dental pulp, keratinized gingiva or alveolar mucosa. Articaine had a significant higher proportion of successful anesthesia at 10 minutes after infiltration in lip mucosa and lip skin (p=0.039). The duration of anesthesia was 336 minutes for bupivacaine and 167 minutes for articaine. (p<0.001). No significant hemodynamic alterations were noted during the procedure. Conclusions: Articaine and bupivacaine exhibited similar anesthetic efficacy for maxillary infiltrations. The duration of anesthesia was longer with the bupivacaine solution, but lip anesthesia was better with articaine

Apical closure device for transapical valve procedures?.

OBJECTIVES: Transapical transcatheter valve procedures are performed through a left minithoracotomy and require apical sutures to seal the apical access site. The use of large-calibre devices compromises any attempt to fully perform the procedure with a thoracoscopic approach or percutaneously. We report our preliminary experience in animals with a new sutureless self-expandable apical occluder, engineered to perform transapical access site closure in a minimally invasive setting with large-size introducer sheaths. METHODS: The apical occluder with extendable waist was implanted in six young pigs during an acute animal study. Under general anaesthesia, animals (mean weight: 62 ± 8 kg) received full heparinization (heparin: 100 UI/kg; activated clotting time above 250 s). Through a median sternotomy, a 21-Fr Certitude? introducer sheath (outer diameter: 25 Fr) was placed over the wire into the cardiac apex. The delivery catheter carrying the constrained apical plug was inserted into the sheath and deployed under fluoroscopic control, whereas the Certitude? was retrieved. After protamine infusion, we observed and recorded the 1-h bleeding with standard haemodynamic parameters. Animals were sacrificed, and hearts analysed. RESULTS: Six apical closure devices were successfully introduced and deployed in six pig hearts through large-size apical sheaths at first attempt. In all animals, the plugs guaranteed immediate apical sealing and traces of blood were collected in the pericardium during the 1-h observational period (mean of 16 ± 3.4 ml of blood loss per animal). Haemodynamic parameters remained stable during the entire study period and no plug dislodgement was detected with normal systemic blood pressure (mean arterial mean blood pressure: 65 ± 7 mmHg). Post-mortem analysis confirmed the full deployment and good fixation of all plugs, without macroscopic damages to the surrounding myocardium. CONCLUSIONS: This sutureless self-expandable apical occluder is a simple device capable of sealing large-size apical access sites (20-35 Fr) in an acute animal study. This approach is a step further towards less invasive transapical valve procedures in the clinical setting, and further animal tests will be performed to confirm the long-term efficacy and safety of this device.

Lineaarisen hammashihnaservokäytön tilasäätö

Tuotantotehokkuus näyttelee yhä suurempaa roolia teollisuudessa, minkä vuoksi myös pakkauslinjas­toille joudutaan asettamaan suuria vaatimuksia. Usein leik­kaus- ja kappaleensiirtosovelluksissa käyte­tään lineaarisia ruuvikäyttöjä, jotka voitaisiin tietyin edellytyksin korvata halvemmilla ja osittain suori­tuskykyisimmillä hammashihnavetoisilla johteilla. Yleensä paikkasäädetty työsolu muodostuu kahden tai kolmen eri koordinaatisto­akselin suuntaan asen­netuista johteista. Tällaisen työsolun paikoitustarkkuuteen vaikuttavat muun muassa käytetty säätöra­kenne, moottorisäätöketjun viiveet, sekä laitteiston eri epälineaarisuudet, kuten kitka. Tässä työssä esitetään lineaarisen hammashihnaservokäytön dynaamista käytöstä kuvaava matemaatti­nen malli ja laaditaan mallin pohjalta laitteen simulointimalli. Mallin toimivuus varmistetaan käytän­nön identifiointitesteillä. Lisäksi työssä tut­kitaan, kuinka hyvään suorituskykyyn lineaarinen hammas­hihnaservokäyttö kyke­nee, jos teollisuudessa paikoitussäätörakenteena tyypillisesti käytetty kaskadira­kenne tai PID-rakenne korvataan kehittyneemmällä mallipohjaisella tilasäädinra­kenteella. Säädön toi­mintaa arvioidaan simulointien ja koelaitteistolla suoritetta­vien mittaus­ten perusteella.