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Surgical Exposure (surgical + exposure)
Selected AbstractsSurgical exposures for distal humerus fractures: A reviewCLINICAL ANATOMY, Issue 8 2008J. Whitcomb Pollock Abstract The majority of distal humerus fractures have complex fracture patterns, with displaced articular segments, requiring operative intervention. The goals of surgery are anatomic reduction and rigid internal fixation via an operative approach that balances maximum required exposure with minimum soft tissue or bony disruption that may necessitate postoperative protection. The selection of a surgical approach depends on multiple factors, including, facture pattern, extent of articular involvement, associated soft tissue injury, rehabilitation protocols, and surgeon preference. This review focuses on the various surgical approaches to the distal humerus. Clin. Anat. 21:757,768, 2008. © 2008 Wiley-Liss, Inc. [source] External Security Stitch for Retrograde Cardioplegia CannulaJOURNAL OF CARDIAC SURGERY, Issue 4 2009Davide Gabbieri M.D. However, this maneuver is time consuming, often implies the loss of surgical exposure, and exposes again the coronary sinus to the risk of iatrogenic injuries. We describe the use of an external security stitch through the muscular right atrial wall to avoid the displacement of a retrograde cardioplegia catheter and analyze the anatomic conditions which predispose to this complication. [source] A Simple Maneuver on Sternal Saw Facilitates to Perform Curved Sternal Mini-incisions like J- and C-Shaped Partial SternotomiesJOURNAL OF CARDIAC SURGERY, Issue 4 2009Koray Ak M.D. To increase the cosmetic benefit and improve the surgical exposure, the length of underlying partial sternotomy is usually 3 to 5 cm longer than the length of skin incision in most of these approaches. Using a standard sternal saw or a rotary craniotome, it is quite difficult to make sternal incision under subcutaneous tissue at both ends of skin incision. Moreover, standard sternal saws do not allow doing fine manipulations on sternum that may cause inadvertent sternal cutting, especially at the curved parts of C- or J-type partial sternotomies. We removed the blade protector part of a standard sternal saw. This simple maneuver enables surgeons to perform several challenging mini-sternotomies easily for adult cardiac procedures. [source] Associated Replacement of Ascending Aorta, Aortic Valve, and Noncoronary Sinus of ValsalvaJOURNAL OF CARDIAC SURGERY, Issue 4 2007Francesco Santini M.D. It offers the advantage to secure stable hemostasis in an area where surgical exposure may be difficult to achieve off-pump. For its easy reproducibility, this procedure might contribute to a more radical resection of diseased tissue thus limiting risk of further dilatation, rupture, and need for reoperation. [source] The Use of a Femoral Arterial Cannula for Effective Dilation for Percutaneous Femoral Venous CannulationJOURNAL OF CARDIAC SURGERY, Issue 1 2005Hrvoje Gasparovic M.D. The technique presented may be particularly helpful when redo sternotomy is deemed hazardous and cardiopulmonary bypass is judged mandatory prior to redo sternotomy. The patient presented in this paper had two previous cardiac operations with prior surgical exposure of femoral vessels in whom institution of cardiopulmonary bypass prior to sternotomy was of paramount importance due to a 7-cm ascending aortic aneurysm. [source] The Results of Probe Technique for Transatrial Repair of Tetralogy of FallotJOURNAL OF CARDIAC SURGERY, Issue 6 2002Ahmet Turan Yilmaz M.D. The most critical point in transatrial repair of TOF is infundibular dissection. Right atrial approach provides better surgical exposure for parietal extension of the infundibular septum when compared to a right ventricular approach. However, it is not always easy to determine the localization and amount of muscle bundles to be resected and this surgical maneuver requires experience. Methods: Nineteen patients were reviewed who had repair of isolated TOF by this technique from 1993 to 2001. The mean age of patients was 5 ± 2 years . Transatrial-transpulmonary approach was performed for all patients. To make the infundibular muscle-bundle resection easier and to determine the localization and amount of muscle bundle to be resected, we placed a Hegar dilator into the right ventricle through pulmonary arteriotomy. The muscle bundles between the dilator and the anterior leaflet annulus of the tricuspid valve were totally excised until the intraventricular part of the dilator and pulmonary annulus became completely visible. The area between the Hegar dilator and the margins of the ventricular septal defect (VSD) was left untouched. None of the patients had transannular patch. Tricuspid valve detachment in order to improve the exposure was done in 11 patients. All patients were followed up in our clinic at regular six-month intervals by echocardiography. Results: There was no early or late mortality nor reoperation for residual VSD or residual right ventricle (RV) outflow obstruction. All patients were in NYHA class I. RV on the echocardiography was spared late dilatation and had a good late functional status. Eighteen patients had no or mild pulmonary regurgitation. One patient who had undergone tricuspid anterior leaflet detachment showed mild tricuspid insufficiency. Conclusions: On the basis of hemodynamic outcomes, this procedure for elective repair of TOF in selected cases gives excellent early and mid-term results.(J Card Surg 2002;17:490-494) [source] Submerged healing following surgical treatment of peri-implantitis: a case seriesJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 8 2007Ann-Marie Roos-Jansåker Abstract Objectives: The aim was to study a regenerative surgical treatment modality for peri-implantitis employing submerged healing. Material and Methods: Twelve patients, having a minimum of one osseointegrated implant with peri-implantitis, with a progressive loss of 3 threads (1.8 mm) following the first year of healing were involved in the study. After surgical exposure of the defect, granulomatous tissue was removed and the implant surface was treated using 3% hydrogen peroxide. The bone defects were filled with a bone substitute (Algipore®), a resorbable membrane (Osseoquest®) was placed over the grafted defect and a cover screw was connected to the fixture. The implant was then covered by flaps and submerged healing was allowed for 6 months. After 6 months the abutment was re-connected to the supra-structure. Results: A 1-year follow-up demonstrated clinical and radiographic improvements. Probing depth was reduced by 4.2 mm and a mean defect fill of 2.3 mm was obtained. Conclusion: Treatment of peri-implant defects using a bone graft substitute combined with a resorbable membrane and submerged healing results in defect fill and clinical healthier situations. [source] Surgical treatment of peri-implantitis using a bone substitute with or without a resorbable membrane: a prospective cohort studyJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 7 2007Ann-Marie Roos-Jansåker Abstract Objectives: The aim of this prospective cohort study was to compare two regenerative surgical treatment modalities for peri-implantitis. Material and Methods: Thirty-six patients having a minimum of one osseointegrated implant, with a progressive loss of bone amounting to 3 threads (1.8 mm) following the first year of healing, combined with bleeding and/or pus on probing, were involved in this study. The patients were assigned to two different treatment strategies. After surgical exposure of the defect, granulomatous tissue was removed and the infected implant surface was treated using 3% hydrogen peroxide. The bone defects were filled with a bone substitute (Algipore®). In 17 patients (Group 1), a resorbable membrane (Osseoquest®) was placed over the grafted defect before suturing. In 19 patients (Group 2), the graft was used alone. Results: One-year follow-up demonstrated clinical and radiographic improvements. Probing depths were reduced by 2.9 mm in Group 1 and by 3.4 mm in Group 2. Defect fill amounted to 1.5 and 1.4 mm, respectively. There was no significant difference between the groups. Conclusion: It is possible to treat peri-implant defects with a bone substitute, with or without a resorbable membrane. [source] Osteogenesis by guided tissue regeneration and demineralized bone matrixJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2003N. Mardas Abstract Aim:, To evaluate in a discriminating capsule model whether bone formation by guided tissue regeneration (GTR) may be influenced by concomitant implantation of demineralized bone matrix (DBM). Materials and Methods:, Thirty 4-month-old male albino rats of the Wistar strain were used in the study. Following surgical exposure of the mandibular ramus, a hemispherical, Teflon capsule (5.0 mm in diameter), loosely packed with a standardized amount of DBM, was placed with its open part facing the lateral bone surface of the ramus. At the contralateral side, an empty capsule was placed, serving as control. After healing periods of 15, 30, and 120 days, groups of 10 animals were sacrificed and 40,70 ,m thick undecalcified sections of the capsules were produced. In the sections, the cross-sectional areas of (1) the space created by the capsule, (2) newly formed bone, (3) DBM particles, (4) loose connective tissue as well as the (5) height of the capsules, and (6) that of the newly formed bone were measured. Results:, Increasing bone fill was observed in both test and control sites from 30 to 120 days. After 30 days of healing, the mean amount of bone was approx. 3% of the cross-sectional area of the capsules at the test sites while it was 8% in the control sites (p<0.05). However, no statistically significant differences were observed between the test (46%) and control (64%) sites after 120 days regarding any of the measured parameters (p>0.05). The newly formed bone in the DBM group at 120 days, on the other hand, appeared more dense than that in the control capsules. Conclusion:, DBM used as an adjunct to GTR did not provide any added effect on bone formation but increased the density of the newly formed bone. Zusammenfassung Ziel: Die Untersuchung in einem Kapselmodell, welches differenzieren kann, ob die Knochenbildung durch GTR durch die gleichzeitige Implantation von demineralisierter Knochenmatrix (DBM) beeinflusst werden könnte Material und Methoden: Dreißig männliche 4-Monate-alte Albinoratten des Wistar Stammes wurden in der Studie verwendet. Nach der chirurgischen Freilegung des Unterkieferastes wurde eine halbkugelförmige Teflonkapsel (5,0 mm Durchmesser), welche locker mit einer standardisierten Menge von DBM versehen war, wurde mit ihrer offenen Fläche auf die seitlichen Knochenfläche des Ramus gelegt. Auf der kontralateralen Seite diente eine leere Kapsel als Kontrolle. Nach Heilungsintervallen von 15, 30 und 120 Tagen wurden Gruppen von 10 Tieren geopfert und 40-70 ,m dicke nicht-entkalkte Schnitte der Kapseln wurden hergestellt. An den Schnitten wurde die Querschnittsfläche von: 1) der Fläche, die von der Kapsel geschaffen wurde, 2) dem neu gebildeten Knochen, 3) den DBM-Partikeln, 4) dem lockeren Bindegewebe gemessen, als auch 5) die Höhe der Kapseln und 6) des neu gebildeten Knochens bestimmt. Ergebnisse: Von Tag 30 zu Tag 120 wurde sowohl bei den Test- als auch bei den Kontrollstellen eine erhöhte Knochenauffüllung beobachtet. Nach 30 Tagen der Heilung betrug an den Teststellen die mittlere Knochenmenge ungefähr 3% der Querschnittsfläche der Kapseln, während sie an den Kontrollstellen 8% (p<0,05) betrug. Jedoch wurde nach 120 Tagen bei keinem der gemessenen Parameter eine statistisch signifikante Differenz zwischen den Test- (46%) und den Kontrollstellen (64%) beobachtet. Auf der anderen Seite erschien nach 120 Tagen in der DBM-Gruppe der neu gebildete Knochen dichter als in den Kontrollkapseln Schlussfolgerung: DBM welches als Zusatz bei der GTR verwendet wurde, lieferte keinen zusätzlichen Effekt bei der Knochenbildung, aber erhöhte die Dichte des neu gebildeten Knochens. Résumé Le but de cette étude a été d'évaluer dans un modèle de capsule discriminatoire si la formation osseuse par regénération tissulaire guidée (GTR) pouvait être influencée par l'implantation concomitante de matrice osseuse déminéralisée (DBM). Trente rats albinos mâles âgés de quatre mois de la souche Wistar ont été utilisés pour cette étude. A la suite de l'exposition chirurgicale de la branche montante mandibulaire, une capsule en téflon hémisphérique de 0,5 mm de diamètre remplie sans tassement avec une quantité standardisée de DBM a été placée avec sa partie ouverte contre la surface osseuse latérale de la branche. Du côté contralatéral, une capsule vide était placée servant de contrôle. Après des périodes de guérison de 15, 30 et 120 jours, des groupes de dix animaux ont été tués et des coupes non-décalcifiées de 40 à 70 ,m d'épaisseur des capsules ont été effectuées. Dans ces coupes, une aire sur coupe transversale contenant 1) l'espace créé par la capsule, 2) l'os néoformé, 3) des particules DBM, 4) du tissu conjonctif lâche; 5) la hauteur des capsules et 6) et celle de l'os néoformé ont été mesurés. Un comblement osseux de plus en plus important tant dans les sites contrôles que les sites tests a été constaté entre les jours 30 et 120. Après 30 jours de guérison, la quantité moyenne d'os formait approximativement 3% de l'aire de la coupe des capsules dans les sites tests tandis qu'elle était de 8% dans les sites contrôles (p<0,05). Cependant, aucune différence statistique n'a été observée entre les sites tests (46%) et les sites contrôles (64%) après 120 jours pour les paramètres mesurés (p>0,05). L'os néoformé dans le groupe DBM à 120 jours semblait plus dense que dans les capsules contrôles. Le DBM utilisé durant la GTR n'apportait aucun effet additionnel sur la formation osseuse mais augmentait cependant la densité du nouvel os formé. [source] No osteonecrosis in jaws of young patients with osteogenesis imperfecta treated with bisphosphonatesJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 4 2008Barbro Malmgren Background:, Recent reports of osteonecrosis of the jaw (ONJ) after dental surgery in patients treated with second- and third-generation nitrogen-containing bisphosphonates instigated this retrospective study. As treatment with bisphosphonates in patients with osteogenesis imperfecta (OI) has become an important symptomatic therapy, especially for severe forms of the disease, we found it important to investigate whether healing after surgical exposure of jaw bone was influenced by the bisphosponate treatment in our group of children, adolescents and young adults with OI. Subjects and methods:, Disodiumpamidronate was given as monthly intravenous infusion to 64 patients with OI aged 3 months to 20.9 years at the start of treatment (mean 8.1, median 7.7). During 0.5,12.5 years of treatment (mean 4.5, median 4.0), a total individual dose of 140,4020 mg/m2 disodiumpamidronate was given (mean 1623 and median 1460). Ten patients continued with oral alendronate and two with zoledronic acid therapy. In 22 of these patients, 38 dental surgery procedures were performed at the age of 3.4,31.9 years (mean 12.2, median 12.3) after 0.03,7.9 years of treatment (mean 3.6, median 3.4). Results:, Despite long-term intravenous monthly disodiumpamidronate treatment, none of the 64 patients had any clinical signs of ONJ. Conclusions:, The risk of ONJ in these patients must be considered so low that the patients with indications for treatment should be treated and get the chance to experience the well-documented beneficial effect for children with severe OI. [source] Patellar blood flow during knee arthroplasty surgical exposure: Intraoperative monitoring by laser doppler flowmetryJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 10 2007Axel Hempfing Abstract Patellofemoral complications following knee arthroplasty are a well-known problem. Patellar ischemia has been suspected to be causative for fracture, anterior knee pain, and patella component failure. The purpose of this study was to assess the influence of knee arthroplasty surgical dissection on patellar blood flow. Patellar blood flow was measured by means of intraosseous laser Doppler flowmetry (LDF) in 10 patients undergoing total knee arthroplasty by a standard medial parapatellar approach. The initial blood flow was 121.6,±,114.7 AU. The signal significantly decreased by 71% (p,=,0.0051) when the knee was flexed and lost the pulsatile signal pattern in 80%. After arthrotomy, the signal was 100.1,±,120.3 AU in extension. The lowest signal was found in flexion and eversion of the patella (mean, 18,±,10.7 AU) and all signals lost pulsatility. As compared to the initial values, completion of the soft tissue dissection did not lead to a significant change of the blood flow signal (121.3,±,104.8; p,=,0.6835). Flexion of the knee joint markedly reduced patellar perfusion. Standard medial parapatellar approach did not significantly change patellar blood flow. This study does not support the theory of postoperative patellar ischemia as a cause of anterior knee pain or patellofemoral problems. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1389,1394, 2007 [source] Indigenous and austere technique of self-retaining abdominal retraction for facilitating surgical exposureJOURNAL OF SURGICAL ONCOLOGY, Issue 5 2006Sajid S. Qureshi MS Abstract Adequate exposure is of paramount importance in major abdominal surgeries. This is achieved by appropriately placed incision, proper position of the patients, and judicious use of retractors. A third assistant is usually required for retaining the retractors. Self-retaining retractors have also been utilized for assisting in adequate exposure of the operative field. However, these retractors are complex and unwieldy, causing hindrance in the movement of the surgeon. We describe a technique of self-retaining abdominal retraction that is simple and also obviates the need for an additional assistant. J. Surg. Oncol. 2006;93:420,421. © 2006 Wiley-Liss, Inc. [source] Anaesthetic choice for palatal canine exposureORAL SURGERY, Issue 1-2 2010S. Hetherington Abstract Aim:, To determine if predicted difficulty of exposure of palatally displaced, unerupted canines assessed by radiographic score had influenced the choice between a local or a general anaesthetic procedure in adolescents. Materials and methods:, This was a retrospective analysis of patients undergoing surgical exposure of palatal canines between December 2005 and June 2008 in a dental hospital setting. A total of 56 subjects, for whom complete records were available, aged 16 years or under and assessed and treated by one surgeon, were included. The predicted degree of difficulty of exposure was graded from preoperative radiographs based on three criteria; the horizontal and vertical position of the crown, and the canine angulation (possible score range 3,11: higher score = more difficulty). The radiographic scores and patient age for the local anaesthetic and general anaesthetic groups were compared using Student's unpaired t -tests. Other variables including gender, other surgical treatment required and unilateral or bilateral exposure were evaluated by chi-squared analysis. Results:, Thirty-one (55%) patients were treated with local anaesthetic and 25 (45%) with general anaesthetic, the mean age was 13.7 years. The mean radiographic scores did not differ between groups being 7.53 and 7.36 for the local anaesthetic and general anaesthetic groups, respectively. Chi-squared analysis showed concurrent other surgical treatment to be the only statistically significant factor in anaesthetic choice. Conclusions:, Difficulty of canine exposure is not a significant factor in anaesthetic choice for adolescents, other concurrent surgical treatment appears a more significant factor in anaesthetic choice in this group. [source] Postoperative continuous intrathecal pain treatment in children after selective dorsal rhizotomy with bupivacaine and two different morphine dosesPEDIATRIC ANESTHESIA, Issue 4 2006KARIN HESSELGARD RN Summary Background:, Children undergoing selective dorsal rhizotomy (SDR) experience severe pain postoperatively; a pain related to both the extensive surgical exposure with multilevel laminectomy and nerve root manipulation. We sought to define an optimal dose of continuous intrathecal (IT) morphine and bupivacaine to treat this severe pain. The aim of this study was to compare two different concentrations of morphine in a fixed dose of bupivacaine with regard to the analgesic effect and survey if they differed in side effects. Methods:, Twenty-six children, aged 2.7,7.4 years undergoing SDR were included in this study. Postoperatively 11 children received a continuous infusion of morphine 0.4 ,g.kg,1.h,1 and bupivacaine 40 ,g.kg,1.h,1 (low-dose group) and 15, a continuous infusion of morphine 0.6 ,g.kg,1.h,1 and bupivacaine 40 ,g.kg,1.h,1 (high-dose group). The Behavioral Observational Pain Scale (BOPS) was used to evaluate pain. Results:, Better pain relief was obtained in the high-dose group seen in lower BOPS score compared with the low-dose group [P = 0.03, Fisher's permutation test and P = 0.06 Wilcoxon,Mann,Whitney (WMW) test]. The low-dose group received seven times as much ketobemidone 0.43 ± 0.54 mg.kg,1 48 h,1 compared with 0.06 ± 0.09 mg.kg,1 48 h,1 in the high-dose group (P = 0.0005 Fisher's permutation test, P = 0.0017 WMW test). There was no statistical difference in pruritus and postoperative nausea and vomiting between the groups. Respiratory and hemodynamic depression was not found. Conclusion:, This study shows that, compared with low-dose, the higher dose of continuous IT morphine combined with bupivacaine, significantly reduce pain score and postoperative intravenous analgesic requirements without increasing adverse effects. [source] Morphologic, functional and behavioral effects of titanium dioxide exposure on nervesCLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2004An experimental study on rats Abstract Objectives: The purpose of this study was to explore morphologic, functional, and behavioral effects of titanium dioxide (TiO2) on nerves. Material and methods: A total of 17 albino rats were used for nerve conduction experiments, hot-plate tests, and histological evaluation. TiO2 was implanted unilaterally on the sciatic nerves of five rats. Ten days after surgery, test and control nerves were dissected and their signal transduction speeds were quantified by suction electrodes in a bath containing a Tyrode solution. Twelve rats were divided into three equal groups resulting in equal number of nerves (n=8) for TiO2 implantation, surgical exposure of the nerves, and for use as controls. One week after surgery, hot-plate tests were undertaken for 10 consecutive days to determine response latencies of the nerves. At the termination of the experiments, the nerves were harvested, processed, and examined under a microscope. Results: The signal transduction speeds of TiO2 -implanted nerves was similar to control specimens (P>0.05). The avoidance responses of TiO2 -implanted, surgically exposed, and control nerves were comparable (P>0.05). At the cellular level, TiO2 did not lead to any signs of adverse reactions on nerves. Conclusions: TiO2, the main oxide surrounding endosseous titanium implants, does not alter the structure and the function of myelinated nerves. Résumé Le but de cette étude a été d'explorer les effets morphologiques, du comportement, de la fonction du dioxide de titane (TiO2) sur les nerfs. Dix-sept rats albinos ont été utilisés pour ces expériences de comportement nerveux, des tests en culture et l'évaluation histologique. Le TiO2 a été implanté unilatéralement sur les nerfs sciatiques de cinq rats. Dix jours après la chirurgie, les nerfs tests et contrôles ont été disséqués et leur vitesse de transduction du signal ont été quantifiée par des électrodes de succion dans un bain contenant une solution de thyrode. Douze rats ont été répartis en trois groupes égaux résultant en un nombre égal de nerfs (n=8) pour l'implantation de TiO2, l'exposition chirurgicale des nerfs et pour l'utilisation comme contrôle. Une semaine après la chirurgie, des tests de culture ont été effectués durant dix jours d'affilée pour déterminer les temps de latence de réponse des nerfs. A la fin des expériences, les nerfs ont été prélevés et examinés sous microscope. Les vitesses de transduction du signal des nerfs où il y avait implantation de TiO2 étaient semblables aux contrôles (P>0.05). Les réponses de manquement des nerfs contrôles, chirurgicalement exposés et implantés TiO2 étaient semblables (P>0.05). Au niveau cellulaire, le TiO2 n'entraînait pas d'effets secondaires sur les nerfs. Le dioxyde de titane, l'oxyde principal entourant les implants titane endoosseux n'altère ni la structure ni la fonction des nerfs myélinisés. Zusammenfassung Ziel: Es war das Ziel dieser Studie, morphologische und funktionelle Verhaltensänderungen eines Nerven als direkte Reaktion auf Titandioxid (TiO2) zu untersuchen. Material und Methode: Man verwendete für Versuche bezüglich Reizleitung der Nerven, für den Kochplattentest und für histologische Untersuchungen insgesamt 17 Albinoratten. Zuerst implantierte man bei fünf Ratten einseitig TiO2 direkt auf den Ischiasnerven. 10 Tage nach der Chirurgie resezierte man die Test- und die Kontrollnerven, legte sie in ein Bad mit Tyrodelösung und mass mit Saugelektroden die Leitgeschwindigkeit eines Signals. Die 12 übrigen Ratten teilte man auf drei gleichgrosse Gruppen auf und erhielt somit je acht Nerven (n=8) für die Implantation von TiO2, die chirugische Entblössung oder für die Kontrollgruppe. Eine Woche nach der Chirurgie führte man an 10 aufeinanderfolgenden Tagen den Kochplattentest durch, um Verzögerungen der Nervenreaktion zu messen. Nach Abschluss dieser Untersuchung entnahm man die Nerven, bereitete sie histologisch auf und untersuchte sie anschliessend unter dem Mikroskop. Resultate: Die Leitgeschwindigkeit eines Signals beim Nerven mit implantiertem TiO2 war ganz ähnlich wie bei den Kontrollnerven (P>0.05). Die Abwehrreaktion von Nerven mit implantiertem TiO2, von chirurgisch entblössten Nerven und von Kontrollnerven war vergleichbar (P>0.05). Auf zellulärer Ebene führte TiO2 zu keiner Abwehrreaktion der Nerven. Zusammenfassung: Titandioxid, anteilsmässig das häufigste Oxid auf enossalen Implantaten, verändert weder Struktur noch Funktion von myelinisierten Nerven. Resumen Objetivos: El propósito de este estudio fue explorar los efectos morfológicos, funcionales y de comportamiento del dióxido de titanio (TiO2) sobre los nervios. Material y métodos: Se usaron un total de 17 ratas albinas para experimentos de conducción nerviosa, pruebas de plato caliente, y evaluación histológica. Se implantó TiO2 unilateralmente en los nervios ciáticos de cinco ratas. 10 días tras la cirugía, se disecaron los nervios de prueba y de control y se cuantificaron sus velocidades de transducción de señales por electrodos de succión en un baño conteniendo solución tiroidea. Se dividió a 12 ratas en tres grupos iguales resultando en igual numero de nervios (n=8) para implantación de TiO2, exposición quirúrgica de los nervios y para usarlos de control. Una semana tras la cirugía, se llevaron a cabo pruebas de plato caliente durante 10 días consecutivos para determinar las latencias de respuesta de los nervios. A la terminación de los experimentos, los nervios se recolectaron, se procesaron y se examinaron bajo el microscopio. Resultados: Las velocidades de transducción de señales de los nervios implantados de TiO2 fueron similares a las de los especímenes de control (P>0.05). Las respuestas de huida de los nervios implantados de TiO2, expuestos quirúrgicamente, y los nervios de control fueron comparables (P>0.05). A nivel celular, el TiO2 no condujo a ningún signo de reacciones adversas en los nervios. Conclusiones: El dióxido de titanio, el óxido principal que rodea a los implantes endoóseos de titanio, no altera la estructura ni la función de los nervios mielínicos. [source] Dog model for study of supracrestal bone apposition around partially inserted implantsCLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2002Ann-Marie Roos-Jansåker Abstract: A dog model for study of supracrestal bone growth around partially inserted implants is described. The mandibular premolar teeth (P1, P2, P3 and P4) were extracted on both sides of the mandible in four dogs. At a surgical exposure 12 weeks later, two 10 mm titanium implants were partially inserted on each side, 15 mm apart, in the areas of the P1 and the P3 so that five threads protruded from the bone crest. A titanium mesh was fastened to the coronal aspect of the two fixtures and covered with an ePTFE membrane. Thus, a space for potential bone formation was created between the two implants. The surgical flaps were coronally positioned and secured with vertical mattress sutures. After 12 weeks of healing, biopsy specimens were retrieved and examined histologically. In three of the four dogs under study, the partially inserted implants had integrated and the intended large wound spaces had been created around the noninserted parts of the implants. However, bone was not formed around the protruding implants. Accordingly, this experimental model may prove useful for future studies on the use of various procedures that hypothetically may enhance bone formation. [source] | |||||||||||||