340 research outputs found

    Anatomical considerations relevant to implant procedures in the mandible

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    The authors review anatomical facts significant for preoperative planning of implant procedures in the mandible. This planning includes the precise evaluation of distinct anatomical factors, such as the position of the mandibular canal, the width of the mandibular cortical plates and the degree of involutive changes of the inferior dental artery.The mandibular canal is usually situated centrally in the mandibular corpus, slightly closer to the lingual cortex in its distal parts; towards the front, it approaches the vestibular cortical layer. Mesially from the mental foramen, a clearly defined incisive canal is present in only one third of the edentate mandibles.Mandibular corpus of the edentate mandibles consists of cancellous bone enclosed by a shell of compact cortical bone. Cortical layers demonstrate significant variations in width; nervertheless, the widths of lateral cortical layers, generally, enable safe placement of endosseal implants.Finally, in patient’s preoperative assessment, involutive changes of the inferior dental artery should also be considered. During the involution of the mandibular alveolar process, it shows changes of direction and calibre, changes in arborization and, sometimes, complete occlusion of the main trunk. The degree of these involutive changes points out the mandibular vascular supply and the regenerative capacity of the tissues needed for the success of the implant procedure.Les auteurs passent en revue les faits anatomiques importants qu’il convient d’avoir Ă  l’esprit en Ă©tablissant le programme prĂ©opĂ©ratoire pour la mise en place d’implants dans la mandibule.Ce programme inclut l’évaluation prĂ©cise des diffĂ©rents facteurs anatomiques tels que la position du canal mandibulaire, la largeur de la corticale mandibulaire et le degrĂ© des changements involutifs de l’artĂšre dentaire infĂ©rieure.Le canal mandibulaire est habituellement situĂ© au centre du corps mandibulaire, trĂšs proche du cortex ventral dans ses portions distales; vers l’avant» il s’approche de la corticale vestibulaire. MĂ©sialement par rapport au foramen mentonnier, un canal incisif bien dĂ©fini est prĂ©sent uniquement dans seulement un tiers des mandibules Ă©dentĂ©es.Le corps mandibulaire des mandibules Ă©dentĂ©es consiste en un os rĂ©duit entourĂ© par un os cortical de type compact. Les couches corticales dĂ©montrent des variations de largeur significatives; nĂ©anmoins, les largeurs des couches corticales latĂ©rales, permettent gĂ©nĂ©ralement le placement d’implants endo-osseux en toute sĂ©curitĂ©.Enfin, au cours de l’établissement du programme prĂ©opĂ©ratoire du patient, les changements involutifs de l’artĂšre dentaire infĂ©rieure devraient Ă©galement ĂȘtre prises en considĂ©ration. Au cours de l’involution du processus alvĂ©olaire de la mandibule, cette artĂšre montre des changements de direction et de calibre, des changements de l’arborisation et quelquefois, une complĂšte oblitĂ©ration de son tronc principal. L’importance de ces changements involutifs, met l’accent sur la supplĂ©ance vasculaire de la mandibule et la capacitĂ© rĂ©gĂ©nĂ©rative des tissus nĂ©cessaires pour le succĂšs de la mise en place des implants

    Morphometric analysis of mandibular canal: clinical aspects

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    Results of morphometric analysis of the mandibular canal (MC), carried out on 105 conserved mandibles, 70 being dentate and 35 edentate, was performed. The analysis was carried out on consecutive sections, at mutual intervals of 0.5 cm. In the mandibular ramus sections were carried out obliquely, approximately in the frontal plane, and horizontally, from mandibular foramen to the lowest region of the vertical part of the MC (all together two sections). In the mandibular corpus, consecutive transversal sections were carried out between existing teeth, or at mutual intervals of 0.5 cm in edentate regions.The obtained results pointed out the very close relationship between the MC and lingual cortical plate of the mandibular ramus. In its horizontal part, the average diameter of the MC was 2.6 mm. It was situated more lingually in the molar region; towards the front, it approached the vestibular cortical plate, being closest to it in the region of the second premolar. Similar relationships of the MC and both cortical plates existed in edentate jaws. Relationships of the MC and tooth root apices varied; however, the MC was closest to the apices of the third molar. Mesially from the mental foramen, a clearly defined incisive canal was present in 92% of the dentale mandibles, but only in 31% of the edentate ones. The nearest to the incisive canal was the apex of the first premolar.The authors point out the importance of presented results in everyday practice, especially in oral and maxillofacial surgery. Having in mind the existing relationship between the MC and neighbouring structures, it is possible to avoid the injury of its content during several oral surgical procedures in mandibular ramus and corpus.L’analyse morphomĂ©trique du canal mandibulaire (CM) a Ă©tĂ© faite sur 105 mandibules conservĂ©es. Parmices mandibules, 70 Ă©taient partiellement Ă©dentĂ©es et 35 totalement Ă©dentĂ©es. Les distances du CM de la couche compacte osseuse de la mandibule et des apex des racines dentaires ont Ă©tĂ© mesurĂ©es sur les coupes successives pratiquĂ©es Ă  une distance de 0,5 cm. Dans la rĂ©gion de la branche montante mandibulaire les coupes successives ont Ă©tĂ© pratiquĂ©es suivant le plan horizontal, de l'orifice postĂ©rieur du canal mandibulaire Ă  la terminaison de la partie verticale du CM. La rĂ©gion du corps mandibulaire a Ă©tĂ© traitĂ©e par des coupes verticales. Ces sections ont Ă©tĂ© faites successivement Ă  travers l’espace entre chaque deux dents ou Ă  une distance de 0,5 cm dans les rĂ©gions Ă©dentĂ©es.Les rĂ©sultats obtenus montrent que le CM se dirige obliquement de haut en bas et en avant, trĂšs proche de la lame osseuse linguale. Dans la partie horizontale son diamĂštre est de 2,6 mm en moyenne. Dans la rĂ©gion des dents molaires le CM est trĂšs proche de la lame osseuse linguale; en cheminant en avant, le CM s’approche de la lame osseuse buccale dont il est le plus proche dans la rĂ©gion de la P2. Dans les mandibules Ă©dentĂ©es, le CM a des rapports semblables.La distance du CM des apex des racines dentaires est variable, pourtant il est le plus proche des apex des racines de la M3. MĂ©sialement du trou mentonnier, le canal incisif Ă©tait clairement individualisĂ© dans 92% des mandibules avec la denture conservĂ©e, et dans 31% des mandibules Ă©dentĂ©es. La premiĂšre prĂ©molaire Ă©tait la plus proche du canal incisif.Les auteurs montrent l’importance des rĂ©sultats prĂ©sentĂ©s pour la stomatologie clinique, surtout pour la chirurgie orale et maxillofaciale. Compte tenu des rapports du CM avec les structures voisines on peut Ă©viter des lĂ©sions de son contenu au cours de certaines interventions chirurgicales sur la branche montante et sur le corps de la mandibule

    Immobilization of cells by electrostatic droplet generation: a model system for potential application in medicine

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    The process of electrostatic extrusion as a method for cell immobilization was investigated that could be used for potential applications in medicine. An attempt was made to assess the effects of cell addition and polymer concentration on the overall entrapment procedure, ie, on each stage of immobilization: polymer-cell suspension rheological characteristics, electrostatic extrusion process, and the process of gelation. The findings should contribute to a better understanding of polymer–cell interactions, which could be crucial in possible medical treatments. Alginate–yeast was used as a model system for carrier-cells. The electrostatic extrusion was considered as a complex two-phase flow system and the effects of cell and alginate concentrations on the resulting microbead size and uniformity were assessed. Under investigated conditions, microbeads 50–600 ÎŒm in diameter were produced and the increase in both alginate and cell concentrations resulted in larger microbeads with higher standard deviations in size. We attempted to rationalize the findings by rheological characterization of the cell–alginate suspensions. Rheological characterization revealed non-Newtonian, pseudoplastic behavior of cell-alginate suspensions with higher viscosities at higher alginate concentrations. However, the presence of cells even at high concentrations (5×108 and 1×109 cells/mL) did not significantly affect the rheological properties of Na-alginate solution. Lastly, we investigated the kinetics of alginate gelation with respect to the quantity of Ca2+ ions and cell presence. The gelation kinetics were examined under conditions of limited supply with Ca2+ ions, which can be essential for immobilization of highly sensitive mammalian cells that require minimal exposure to CaCl2 solution. The molar ratio of G units to Ca2+ ions of 3.8:1 provided complete crosslinking, while the increase in alginate concentration resulted in prolonged gelation times but higher strength of the resulting gel. The cell presence decreased the rate of network formation as well as the strength of the obtained Ca-alginate hydrogel

    Antioxidant Capacities and Phenolic Levels of Different Varieties of Serbian White Wines

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    The biologically active compounds in wine, especially phenolics, are responsible for reduced risk of developing chronic diseases (cardiovascular disrease, cancer, diabetes, etc.), due to their antioxidant activities. We determined the contents of total phenolics (TP) and total flavonoids (TF) in selected Serbian white wines by colorimetric methods. Total antioxidant activity (TAA) of the white wines was analyzed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay. Međaơ beli had the highest content of TP, TF and TAA. The radical scavenging capacity (RSC) and total antioxidant activity (TAA) of white wines were 15.30% and 1.055 mM Trolox equivalent, respectively. Total phenolic (TP) and total flavonoid (TF) contents in white wines ranged from 238.3 to 420.6 mg gallic acid equivalent per L of wines and 42.64 to 81.32 mg catechin equivalent per L of wines, respectively. A high and significant correlation between antioxidant activity and total phenolic content was determined in wines (R2 = 0.968, p < 0.01). For the individual polyphenols determination we used a high performance liquid chromatography (HPLC)-diode array detection (DAD) technique. The majority of white wine polyphenols was represent by four hydroxycinnamic acids (HCAs)

    Les rapports du canal mandibulaire avec les faces externes du corps de la mandibule et risques qui en découlent de le léser

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    The investigations of relations and position of the mandibular canal (CM) were carried out on 80 mandibles (33 dentulous, 27 partly edentulous and 20 completely edentulous).The studies of relations of CM to the sides of mandibular body were accomplished by morphometric analysis of CM on consecutive transversal sections of mandibular body (54 preparations). The relation of the CM to be buccal or to the lingual side is expressed as the distance from the surface of the correspondent side of the mandibular body, which is shown in Table 1. According to these data, the position of the canal is at first proximate to the lingual side, and from the first molar tooth (M1) it approaches the buccal surface of the mandibular body.The position of the entire CM was determined by analysis of mandibular preparations (26) after removing the buccal osseous lamina. These investigations revealed that the position of the CM is predominantly buccal. Reconstruction of relations of the CM to the sides of mandibular body, according to the data obtained from transversal sections, and the real position of the CM are presented in Scheme I.The difference in direction lines of relations and of predominant position of the CM is a consequence of morphological characteristics of mandibular body.Le CM a Ă©tĂ© Ă©tudiĂ© sur 80 mandibules (dont 33 avec la denture conservĂ©e, 27 peu Ă©dentĂ©es et 20 totalement Ă©dentĂ©es). L’analyse morphomĂ©trique des rapports du CM a Ă©tĂ© faite sur les coupes frontales de la mandibule (54). La position du CM en entier a Ă©tĂ© examinĂ©e aprĂšs la trĂ©panation du corps mandibulaire (26 prĂ©parations). La reconstruction des rapports du CM d’aprĂšs les donnĂ©es obtenues sur les coupes fait apparaĂźtre que le canal a d’abord une position linguale, ensuite il croise la M1 et se termine dans une position buccale. Dans la plupart des cas, le CM a, dans la majeure partie de son trajet, une position buccale Ă  cause de la configuration caractĂ©ristique du corps mandibulaire

    Polyphenol Content and Antioxidant Activity of Sour Cherries From Serbia

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    The aim of this study was to evaluate the content of phenolics: the total phenols (TP), flavonoids (TF), anthocyanins (TA), as well as the total antioxidant\ud capacity (TAC) in three sour cherry cultivars (Prunus cerasus L.) introduced to the southeast Serbia climate conditions. Among the investigated sour cherries,\ud „Oblačinska“ cultivar contained the highest amounts of all groups of phenolics, followed by „Cigančica“ > „Marela“. A significant difference were observed in the phenolic content among different cultivars and growing seasons (p  0.05), and the phenolic compounds were significantly higher in the growing season 2009. The examined cultivars possess a high antioxidant capacity, and all phenolics of highy correlation with TAC. The following compounds were identified and quantified using HPLC-DAD: 4 anthocyanins, the most abundant of which was cyanidin-3-glucoside in “Marela” and “Oblačinska”, and cyanidin-3-glucosylrutinoside in „Cigančica“, and 4 hydroxycinnamic acids, the most abundant of which was neochlorogenic acid in all sour cherry cultivars. The growing and ripening process on the tree of sour cherry cv. „Oblačinska“ was evaluated also. The results showed significant increases in total phenols during the ripening, the total anthocyanins and total antioxidant capacity and 4 quantified anthocyanins, however the neochlorogenic acid decreased during the ripening. The study indicated that the growing and climate conditions in southeast Serbia are convenient for introducing sour cherry cultivars.\u

    Anatomie chirurgicale de la glande sublinguale

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    Because of its position, the sublingual gland is clinically important especially in the events of injuries and infections in the anterior part of the sublingual region.The morphology and relationships of this gland were studied by dissection methods applied on 80 fresh or formaldehyde fixed preparations of the mouth floor and of the tongue, which were partly (31 preparations) taken out together with the mandible.As for the shape of the gland, three main types were found: 1° the cuneiform type which was the most frequent (71 %), 2° the pyramidal type which was less frequent (16%) and the fusiform type (13%) which comprised the cases of a very elongated gland (up to 65 mm).The space in which the gland lied had four walls. Its internal wall consisted of the mylohyoid muscle and it comprised the hyoglossus muscle as well when the gland was very elongated. The inferior wall consisted of the mylohyoid muscle and sometimes it comprised also a narrow part of the superior surface of the geniohyoglossus muscle. An osseous depression on the internal side of the mandible represented the external wall of the sublingual gland space. The superior wall is clinically the most significant. It consists of the sublingual mucosa and a sublingual fold. This wall represents a main surgical access to the gland. In edentulous mandibles this mucous fold may be at the level of the upper mandibular border which may hinder the use of the lower dental prosthesis.La morphologie et les rapports de la glande sublinguale ont été étudiés par 80 dissections du plancher de la bouche et de la langue.Trois types différents de glandes ont été définis du point de vue forme: le type cunéiforme (71%), le type pyramidal (16%) et le type fusiforme (13%).La loge de la glande sublinguale possÚde quatre parois: deux (parois inférieure et interne) de nature musculaire, une (paroi externe) de nature osseuse et une (paroi supérieure) de nature muqueuse

    La structure osseuse de la branche montante de la mandibule

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    Osseous structure of the ramus of mandible (RM) is of a practical clinical significance. Osteosynthesis of fractured segments and the success of the sagittal or the horizontal ramus split osteotomy depends on the cortical bone disposition and thickness.After morphometric investigations of the RM, conducted on 70 mandibles of adults, consecutive horizontal and frontal sections were made. On these sections, the cortical layer was studied and the cortical bone thickness was measured at four previously marked points.In the regard of morphometry, the significant datum is that nearly half of all the cases is grouped round the mean value of any parameter.Cortical bone is continuous and its two main sheets are the buccal and the lingual cortical plates. In its entirety, the buccal cortical plate is thicker than the lingual. The thickness of both cortical plates increases in the direction from the coronoid process to the angle of mandible.L’ostĂ©osynthĂšse de la branche montante de la mandibule et le succĂšs de l’ostĂ©otomie sagittale ou horizontale de cette branche dĂ©pendent de la disposition et de l’épaisseur de sa couche osseuse compacte. Les examens morphomĂ©triques qui ont Ă©tĂ© faits sur 70 mandibules des sujets adultes montrent que presque la moitiĂ© de tous les cas se groupent autour de la valeur moyenne des paramĂštres mesurĂ©s (schĂ©ma 1 et tableau I).Sur les coupes horizontales et frontales, l’épaisseur des lames compactes buccale et linguale a Ă©tĂ© mesurĂ©e dans certains points prĂ©dĂ©terminĂ©s et il a Ă©tĂ© Ă©tabli que la lame buccale est toujours plus Ă©paisse (schĂ©ma 2 et tableau II)

    AltĂ©rations athĂ©rosclĂ©reuses de l’artĂšre dentaire infĂ©rieure en corrĂ©lation avec celles de la bifurcation carotidienne et de l’aorte abdominale

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    50 corpses from adults aged 20 to 75 have been used in order to study the atherosclerotic lesions occurring in typical regions (bifurcation of the common carotid artery and the abdominal aorta) and their relationship to atherosclerotic changes in the inferior alveolar artery. Histological analysis revealed that atherosclerotic alterations of the inferior alveolar artery may appear sometimes earlier than it would be expected on the ground of age. Intima cell proliferation and thickening of elastic elements in the middle layer of the arterial wall, the first signs of atherosclerosis, were found already at the beginning of the third decade of life when the signs of this process in the typical regions were not yet evident. Atherosclerosis affects essentially the functional capacity of the inferior alveolar artery. The development of atherosclerosis in the wall of this artery favours an hypovascularization of the mandible, which must be of certain importance in every operative procedure in oral surgery, especially in those inducing a severe and long traumatism in bone and soft tissues, such as dental implantations.Cette Ă©tude, faite sur 50 cadavres (de 20 Ă  75 ans) concerne les altĂ©rations athĂ©rosclĂ©reuses de l’artĂšre dentaire infĂ©rieure et leurs rapports avec les altĂ©rations athĂ©rosclĂ©reuses dans les territoires typiques (bifurcation carotidienne et aorte abdominale). L’examen histologique a fait apparaĂźtre que les altĂ©rations athĂ©rosclĂ©reuses de l’artĂšre dentaire infĂ©rieure peuvent ĂȘtre relativement plus Ă©videntes et prĂ©coces que l’on ne s’y attendrait compte tenu de l’ñge. Une prolifĂ©ration cellulaire de l’intima et un Ă©paississement de la lame Ă©lastique moyenne dans la paroi artĂ©rielle, premiers signes de l’athĂ©rosclĂ©rose, peuvent apparaĂźtre dĂšs30 ans, alors que l’on ne trouve pas encore d’altĂ©rations de ce type dans les territoires typiques. L’athĂ©rosclĂ©rose a une influence cruciale sur la capacitĂ© fonctionnelle de l’artĂšre dentaire infĂ©rieure puisque celle-ci chemine dans le canal osseux, qui empĂȘche sa dilatation. Le dĂ©veloppement de l’athĂ©rosclĂ©rose dans la paroi de cette artĂšre favorise une hypovascularisation de la mandibule, ce qui a une importance certaine lors de toute intervention en chirurgie orale, surtout lorsqu’elle entraĂźne un traumatisme grave et prolongĂ©e de l’os et des parties molles, comme c’est le cas lors de l’insertion d’implants dentaires

    Illness perception in tuberculosis by implementation of the Brief Illness Perception Questionnaire : a TBNET study

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    How patients relate to the experience of their illness has a direct impact over their behavior. We aimed to assess illness perception in patients with pulmonary tuberculosis (TB) by means of the Brief Illness Perception Questionnaire (BIPQ) in correlation with patients’ demographic features and clinical TB score. Our observational questionnaire based study included series of consecutive TB patients enrolled in several countries from October 2008 to January 2011 with 167 valid questionnaires analyzed. Each BIPQ item assessed one dimension of illness perceptions like the consequences, timeline, personal control, treatment control, identity, coherence, emotional representation and concern. An open question referred to the main causes of TB in each patient’s opinion. The over-all BIPQ score (36.25 ± 11.054) was in concordance with the clinical TB score (p ≀ 0.001). TB patients believed in the treatment (the highest item-related score for treatment control) but were unsure about the illness identity. Illness understanding and the clinical TB score were negatively correlated (p < 0.01). Only 25% of the participants stated bacteria or TB contact as the first ranked cause of the illness. For routine clinical practice implementation of the BIPQ is convenient for obtaining fast and easy assessment of illness perception with potential utility in intervention design. This time saving effective personalized approach may improve communication with TB patients and contribute to better behavioral strategies in disease control
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