Fabricating a dual-material, vat-polymerized, additively manufactured static implant surgical guide: A dental technique.

Protocols with static computer-aided implant placement provide more tangible clinical advantages than conventional implant placement methods. A technique to manufacture a dual-material implant surgical guide by using a vat-polymerization printer is described. The implant surgical guide combined a resilient intaglio and hard exterior surface. The technique should minimize the clinical adjustments needed to ensure fit and improve patient comfort.

El reto del abordaje quirúrgico en la rehabilitación sobre un implante unitario en un caso de alto requerimiento estético del sector anterior. Descripción a propósito de un caso / The challenge of the surgical approach in the rehabilitation of a unitary implant in a case of high aesthetic requirements of the anterior sector. Case report

Objetivo: Describir de forma detallada el abordaje clínico basado en la evidencia científica actual de un implante postextracción con carga y provisionalización inmediata. Caso clínico: Se presenta el caso de una paciente mujer de 32 años de edad, que acude por presentar una posible fractura radicular del incisivo central superior izquierdo (ICSI), acompañada de la aparición de un absceso periodontal en la región del fondo de vestíbulo de dicho diente. Tras llevar a cabo la exploración clínica y radiológica, se establece que el pronóstico del ICSI es desfavorable para llevar a cabo un tratamiento conservador del mismo. Tras la valoración de las características clínicas del caso presente, el plan de tratamiento se inclinó por la realización de la exodoncia del ICSI con la colocación simultánea de un IOI postextracción y la carga inmediata con una prótesis provisional del mismo. Conclusiones: La rehabilitación sobre implantes en situaciones de pérdida dental en el sector anterior estético y en especial, en pacientes jóvenes, requiere un plan de tratamiento multidisciplinar en cuanto a la extracción del diente y colocación del IOI en la posición tridimensional correcta, existiendo diferentes aspectos a tener en cuenta para ello, especialmente el remanente óseo residual, la posición del margen gingival, así como la preservación y acondicionamiento de los tejidos duros y blandos periimplantarios mediante injertos y un manejo correcto de una prótesis provisional hasta conseguir un perfil de emergencia y contorno gingival ideal antes de la corona definitiva. (AU)

Objective: To describe in detail the clinical approach based on current scientific evidence for a post-extraction implant with immediate loading and provisionalisation. Clinical case: We present the case of a 32-year-old female patient who presented with a possible root fracture of the upper left central incisor (ULCI), accompanied by the appearance of a periodontal abscess in the region of the bottom of the vestibule of said tooth. After carrying out the clinical and radiological examination, it is established that the ULCI prognosis is unfavourable for carrying out conservative treatment of the tooth. After assessing the clinical characteristics of the present case, the chosen treatment plan was to extract the ULCI with the simultaneous placement of a post-extraction osseointegrated implant (OII) and immediate loading of a provisional prosthesis on the implant. Conclusions: Rehabilitation on implants in situations of tooth loss in the aesthetic anterior sector, especially in young patients, requires a multidisciplinary treatment plan in relation to tooth extraction and placement of the OII in the correct three-dimensional position. There are various aspects to be taken into account, particularly the residual remaining bone, the position of the gingival margin, as well as the preservation and conditioning of the peri-implant hard and soft tissues by means of grafts and proper handling of a provisional prosthesis until an ideal emergence profile and gingival contour is achieved before the final crown. (AU)

Patogénesis del dolor en la mucositis oral. Revisión de la literatura / Pathogenesis of pain in oral mucositis. Review of the literature

INTRODUCCIÓN: La mucositis oral es una lesión dolorosa que tiene lugar en la mucosa de la cavidad oral, normalmente su etiología se encuentra asociada a tratamientos farmacológicos en pacientes oncológicos. Se presenta como úlceras bien delimitadas cuya sintomatología dolorosa supone en ocasiones la suspensión del tratamiento oncológico o la alimentación por vía parenteral, siendo por tanto un efecto adverso importante, marcando el devenir en este tipo de terapias contra el cáncer. OBJETIVO: El objetivo del presente artículo es poner en relieve cómo se produce el dolor en esta patología que acontece en la mucosa de la cavidad oral. DISCUSIÓN: La mucositis oral se va a presentar tras una cascada de eventos biológicos que implican diferentes procesos moleculares tras el tratamiento con quimioterapia o radioterapia. El dolor en la mucositis oral puede poseer un componente inflamatorio y también un componente neuropático. En su fisiopatología, el dolor va a estar mediado por diferentes familias de receptores y factores. CONCLUSIÓN: La mucositis oral presenta un gran componente doloroso asociado, en el que cobran especial protagonismo en su aparición, las familias de los receptores y factores TRP, ET-1, TNF y ROS, entre otros. El conocimiento de la patogénesis del dolor en esta patología permitirá desarrollar terapéuticas contra el dolor en estudios futuros

INTRODUCTION: Oral mucositis is a painful lesion that occurs in the mucosa of the oral cavity. Its aetiology is usually associated with drug treatments in cancer patients. It presents as well-defined ulcers whose painful symptoms sometimes lead to the suspension of cancer treatment or parenteral nutrition. They therefore represent a significant adverse effect that marks the future in this type of cancer therapy. OBJECTIVE: The objective of this article is to highlight how pain occurs in this pathology that takes place in the mucosa of the oral cavity. DISCUSSION: Oral mucositis will occur following a cascade of biological events involving different molecular processes following treatment with chemotherapy or radiotherapy. Pain in oral mucositis may have an inflammatory component as well as a neuropathic component. In its pathophysiology, pain will be mediated by different families of receptors and factors. CONCLUSION: Oral mucositis has a large associated painful component, in which the families of TRP, ET-1, TNF and ROS receptors and factors, among others, play a major role in its appearance. Knowledge of the pathogenesis of the pain in this pathology will allow pain therapies to be developed in future studies

The challenge of the surgical approach in the rehabilitation of an anterior sector unitary implant in a case of high aesthetic requirements; case report

Objective: Provide a detailed description of the current evidence-based clinical approach to a post-extraction implant with immediate loading and provisionalisation. Clinical case: A 32-year-old female patient who attended for a possible root fracture of the upper left central incisor (ULCI), accompanied by a periodontal abscess at the bottom of the vestibule of the same tooth. A clinical and radiological examination established that the prognosis of the ULCI was unfavourable for conservative treatment. After evaluating the clinical features of the case, the treatment plan to extract the ULCI followed immediately by an osseointegrated implant (OII) and loading of a provisional prosthesis on the implant. Conclusions: Rehabilitation on implants in situations of tooth loss in the aesthetic anterior sector, especially in young patients, requires a multidisciplinary treatment plan to extract the tooth and insert an OII in the correct 3-dimensional position. Various aspects need to be taken into account for this, particularly the residual remaining bone, the position of the gingival margin and preservation and conditioning of the peri-implant hard and soft tissues by means of grafts and proper handling of provisional prosthesis, until an ideal emergence profile and gingival contour is achieved before the final crown. (AU)

Fístula de líquido cefalorraquídeo del receso lateral de seno esfenoidal: ¿Es el canal de Sternberg un defecto real? / Cerebrospinal fluid leak of the lateral recess of the sphenoid sinus: is Sternberg's channel a real defect?

RESUMEN Las fístulas de líquido cefalorraquídeo (LCR) corresponden a una comunicación anómala entre el espacio subaracnoideo y la cavidad nasal. El origen de las fístulas laterales del seno esfenoidal se encuentra en un defecto congénito de la base del cráneo, con una incompleta o prematura fusión de los componentes óseos implicados en el complejo proceso de osificación del esfenoides. Ello origina un canal sin cobertura ósea, solo cubierto por tejido conectivo, denominado canal craneofaríngeo lateral o de Sternberg. Este es un punto débil donde pueden aparecer encefaloceles y/o fístulas, su ubicación lateral en el seno constituyen una zona de difícil abordaje quirúrgico. La reparación quirúrgica de fístulas de LCR ha progresado drásticamente con el desarrollo de ópticas endoscópicas y la mejora en el conocimiento de la anatomía de la base de cráneo. Los endoscopios permiten una visualización directa, localización del defecto y por ende una reparación precisa que traduce menos recidivas y menor morbilidad asociada a accesos transcraneales realizados previamente. El propósito de este artículo es presentar el caso de paciente con fístula del receso lateral del seno esfenoidal, su reparación endoscópica y discusión del origen de la persistencia del canal de Sternberg como causa del defecto.

ABSTRACT Fístulas liquid cerebrospinal (CSF) correspond to an abnormal communication between the subarachnoid space and the nasal cavity. The origin of lateral fístulas of the sphenoid sinus is a congenital defect of the skull base, with an incomplete or premature fusion of bone components involved in the complex process of ossification of sphenoid. This originates a channel without bone coverage, only covered by connective tissue, called channel craneofaringeo or Sternberg channel. This is a weak point where may appear encephaloceles and/or fístula, the lateral location in sinus is a difficult surgical approach. Surgical repair of fístulas of CSF has progressed dramatically with the development of endoscopic optics and the improvement in the knowledge of the anatomy of the skull base. Endoscopes enable a direct visualization, location of the defect and thus accurate reparation and less morbidity associated with transcraneales accesses made previously. The purpose of this article is to present the case of patient with fístula of the lateral recess of the sphenoid sinus, endoscopic repair and discussion of the origin of the persistence of the channel of Sternberg as a cause of the defect.

Subepithelial inflammatory load and basement membrane thickening in refractory chronic rhinosinusitis with nasal polyposis: a histopathological study.

BACKGROUND: A subgroup of chronic rhinosinusitis with nasal polyps (CRSwNP) patients is refractory to optimal surgical therapy and requires multiple revision sinus operations. Studies have shown that mucosal eosinophilia correlates with disease severity. We hypothesized that a high-grade tissue inflammatory load is associated with these refractory patients. METHODS: A single-surgeon, retrospective case-control study comparing 20 CRSwNP patients requiring a second surgery during follow-up (refractory group) vs a matched cohort of 20 CRSwNP patients without needing further revision surgery (control group). Hematoxylin and eosin (H&E)-stained tissue harvested intraoperatively (×2 for the refractory group) were recalled for histopathological examination of subepithelial inflammation and basement membrane (BM) thickness. RESULTS: The refractory group had a significantly higher average eosinophil count (49 vs 18), relative eosinophilia (55% vs 32%) as well as total inflammatory cell count (86 vs 49) than the control group (p < 0.05). However within the refractory group, the eosinophil-lymphocyte ratio was reduced from their first to their second (revision) surgeries whereas the total averaged inflammatory cell count remained unchanged. No significant difference in BM thickness was found between the groups. CONCLUSION: These findings suggest that a higher inflammatory and eosinophilic load is associated with refractory disease and thus may be useful in predicting need for future revision surgery in CRSwNP.

Staphylococcus aureus biofilms induce apoptosis and expression of interferon-γ, interleukin-10, and interleukin-17A on human sinonasal explants.

BACKGROUND: Staphylococcus aureus is one of the most common bacteria associated with chronic rhinosinusitis (CRS). Although S. aureus biofilms have been correlated with disease severity in CRS, little is known about the initial immune response that biofilms induce in the sinonasal mucosa. OBJECTIVE: The aim of this study was to evaluate the innate immune response (in terms of cytokines) of nondiseased human sinonasal tissue to S. aureus biofilms. METHODS: Full-thickness sinonasal explant cultures (n = 7 donors) were challenged with established S. aureus biofilms for 24 hours. The expression profiles of 17 cytokines were measured using multiplex analysis, real-time quantitative reverse transcription polymerase chain reaction, and immunohistochemistry. Differences in expression were evaluated using Student's t-test. RESULTS: Interleukin (IL)-1ß, IL-10, TNF, IL-17A, and interferon (IFN)-γ were up-regulated at the RNA and protein levels in biofilm-treated tissues compared with controls. Elevation of caspase-3 in biofilm-treated samples indicates S. aureus biofilms induce apoptosis on the sinonasal mucosa. CONCLUSION: S. aureus biofilms induced apoptosis and a predominant proinflammatory immune response on normal sinonasal mucosal explants. This immune response appeared to be triggered by intrinsic bacterial elements but also by components of the biofilm matrix. Live biofilms were present on the mucosa at the end of the challenge, suggesting an inability of the induced immune response to eliminate the S. aureus biofilms.

Esofagitis aguda inducida por doxiciclina

Se presenta caso de mujer joven con odinofagia intensa de inicio agudo. La endoscopía digestiva y biopsia esofágica confirman esofagitis isquémica aguda. Tras interrogatorio repetido se encontró asociación causal con ingesta previa de cápsula de doxiciclina utilizada para tratamiento de acné.

We present the case of a young woman with severe odynophagia of acute onset. The digestive endoscopy and esophageal biopsy confirmed an acute ischemic esophagitis. After repeated interviews, a causal association with prior ingestion of doxycycline capsule used for acne treatment was found.

Staphylococcus aureus biofilm activates the nucleotide-binding oligomerization domain containing 2 (Nod2) pathway and proinflammatory factors on a human sinonasal explant model.

BACKGROUND: The presence of Staphylococcus aureus biofilms on sinonasal mucosal surfaces is associated with recalcitrant chronic rhinosinusitis (CRS), but little is known about the innate immune response they trigger. We aimed to study the human pattern recognition receptor (PRR) nucleotide-binding oligomerization domain containing 2 (Nod2) receptor and downstream pathway in response to initial S. aureus biofilm infection. METHODS: Using a validated protocol, sinonasal mucosae from 4 non-CRS donors were cultured with and without S. aureus biofilms and planktonic cells. After 24 hours, RNA was extracted and gene expression was analyzed using a human antibacterial response polymerase chain reaction (PCR) array. Immunohistochemistry was performed to confirm the presence and determine the immunolocalization of selected proteins. RESULTS: C-X-C motif (CXC) chemokine ligands 1 and 2, interleukin-6 (IL-6), and genes related to the Nod2 pathway were significantly upregulated in biofilm-treated tissues compared with control samples. Nod2 pathway-specific gene expression was increased in biofilm-treated tissues compared with planktonic S. aureus-treated explants. Enhanced expression of Nod2 and nuclear factor kappa B1 (NF-κB1) was also detected with immunohistochemistry in control and biofilm-treated tissues. CONCLUSION: S. aureus biofilms exerted a proinflammatory response in the mucosa and activation of the Nod2 pathway, indicating this receptor to be involved in the innate immune response to S. aureus biofilms. Further studies are required to elucidate the role of this pathway in CRS.

A human nasal explant model to study Staphylococcus aureus biofilm in vitro.

BACKGROUND: Staphylococcus aureus (S. aureus) biofilm has been associated with severe and recalcitrant cases of chronic rhinosinusitis (CRS). However, its role in the pathophysiology of this condition is not completely understood. This study aims to develop a sinonasal tissue explant model to analyze the interaction of S. aureus biofilm with the mucosa in vitro. METHODS: Sinonasal tissue samples from 5 control patients undergoing pituitary surgery were cultured with and without S. aureus biofilm in vitro. Confocal scanning laser microscopy (CSLM) using the Live/Dead BacLight stain and histology were performed on the tissue explants after 24 hours of biofilm challenge. Measurements of IL-6, at both the messenger RNA (mRNA) level (using quantitative reverse-transcriptase polymerase chain reaction [qRT-PCR]) and the protein level (using enzyme-linked immunosorbent assay [ELISA]), were undertaken to evaluate biofilm-mucosa interaction. RESULTS: Viability of the explants after 24 hours was confirmed by CSLM and histology. Although light microscopy failed to identify S. aureus biofilms, its presence was confirmed in the biofilm-challenged samples by CSLM. IL-6 mRNA transcript levels were 4.9-fold upregulated in biofilm-treated tissue compared to controls (p = 0.0485). A similar trend was observed at the protein level (p = 0.0313). CONCLUSION: The sinonasal tissue explant is a viable and functional model capable of analyzing direct biofilm-mucosal interactions and can advance our understanding of the role played by S. aureus biofilm in sinus inflammation. Our model suggests that S. aureus biofilms in the initial phase of growth are not inert bystanders but elicit an immune response in the sinonasal mucosa.

Importancia de la sabiduría didáctica práctica como fuente de conocimiento base para la enseñanza de la anatomía / Importance of teaching practical wisdom as a source of knowledge base for teaching anatomy

La sabiduría práctica es uno de los conocimientos base que se propone para generar prácticas de enseñanza de calidad en el campo de la medicina. Se planteó un diseño metodológico cualitativo ­ comprehensivo con el propósito de describir la importancia de la sabiduría didáctica práctica como fuente de conocimiento base para la enseñanza de la anatomía en docentes de la Universidad Mayor de Temuco, esto al amparo de la teoría fundamentada, el método comparativo constante y los principios de triangulación y convergencia. La muestra se constituyó con la totalidad de los docentes de la cátedra de Anatomía. Para el análisis de datos se consideró la codificación abierta, de la cual emergieron dos categorías: a) desempeño experto y b) principios de la sabiduría práctica. Las técnicas de recolección de información fueron: observación etnográfica, entrevista semiestructurada y grupos focales. Para el procesamiento de data verbal se utilizó el software para el análisis cualitativo de datos Atlas-ti versión 5.0. Los resultados del estudio develan que la sabiduría didáctica práctica es una fuente de conocimiento relevante en toda práctica pedagógica, valorizándose como el principal conocimiento base para la formación en medicina, en consecuencia se desafía a los profesionales de la enseñanza de la medicina a realizar un tránsito desde el nivel de profesionalidad de principiante hacia un nivel de profesor experto.

Practical wisdom is one of the proposed base knowledge to generate best practices for teachings in the field of medicine. A methodological qualitative-comprehensive design was proposed with the purpose of describing the importance of the didactical practical wisdom as source of base knowledge for the teaching of anatomy by the faculty of the Universidad Mayor of Temuco, this was done based on the founded theory, constant comparative method and principles of triangulation and convergence. The sample was composed of the entire faculty team for the anatomy course. For the analysis of the data, open codification was considered, from which two categories surfaced: a) expert performance and b) principles of practical wisdom. The techniques for data gathering were: ethnographic observation, semi structured interview and focus groups. The processing of the verbal data was done by means of a software for qualitative analysis, Atlas-ti version 5.0. The results of the study show that didactical practical wisdom is a source of relevant knowledge in all pedagogical practice, assessing it as the principal base knowledge for the training in medicine, therefore a challenge is made to all professionals involved in teaching medicine to transition from basic professionalism into an expert one.

Desafíos para la transposición didáctica y conocimiento didáctico del contenido en docentes de anatomía: obstáculos y proyecciones / Challenges to the didactic transposition and knowledge of the content in teaching of anatomy: obstacles and projections

La enseñanza de la Anatomía a nivel de pre-grado exige una formación basada en competencias que genere resultados de aprendizajes, donde converjan saberes sabios de la disciplina con saberes didácticos de la pedagogía. Para ello, se planteó un diseño cualitativo de investigación con el propósito de describir desafíos, obstáculos y proyecciones de la transposición didáctica y el conocimiento didáctico del contenido disciplinario de la Anatomía en la Escuela de Medicina de la Universidad Mayor de Temuco, en base a la Teoría Fundamentada, Método Comparativo Constante y Triangulación Metodológica. La muestra se constituyó con la totalidad de los docentes de la cátedra de Anatomía. A partir de la codificación abierta emergieron cinco categorías: a) dificultades del ejercicio docente, b) recursos materiales y humanos, c) planificación y estrategias de evaluación, d) estrategias de enseñanza-aprendizaje y e) requerimientos y características. Las técnicas de recolección de información fueron: observación etnográfica, entrevista semiestructurada y grupos focales. Para el procesamiento de data verbal se utilizó el software para el análisis cualitativo de datos Atlas-ti versión 5.0. Los resultados del estudio develan incoherencias de carácter epistémico en la actuación didáctica de los docentes, quienes sitúan su práctica desde la lógica tradicionalista experiencial, apartándose de métodos dialógicos dialécticos necesarios en la actual cartografía sociocultural de la que forman parte los estudiantes de Pre-grado.

Teaching undergraduate level anatomy classes demands a "formation" based in competences that provides learning results, where both "saberes sabios" and "saberes didacticos" converge. For that purpose, a qualitative design of research was proposed with the intent of describing requirements and characteristics of the teaching of anatomy courses in the medical school at the Universidad Mayor in Temuco, based on "grounded theory", "Constant Comparative Method" and "Methodological Triangulation". The sampling was composed of the entire teaching staff for the anatomy courses. As a result of open coding five categories were identified, and for this article the most representative one has been chosen: "requirements and characteristics of the teaching of anatomy". The techniques used for gathering information were "ethnographic observation", "structured interview" and focus groups. Data"reduction" was done with help of software for qualitative data analysis called "Atlas-ti" v5.0. The results of the study reveal incoherencies of "epistemic" character in the "didactic performance" of the teaching staff, who base their practice from the experimental logic, staying away of methods "dialogicos dialecticos" needed in the current sociocultural "cartography" shown by undergraduate level students.

Spiral enteroscopy and push enteroscopy.

Spiral enteroscopy is a new technique for endoscopic evaluation of the small bowel. Currently, more than 3000 cases have been performed worldwide. The Discovery SB device has been approved by the Food and Drug Administration and has been granted a CE mark. The technique is safe and effective for management and detection of small bowel pathology. Recent studies of spiral enteroscopy have demonstrated diagnostic yield, total time of procedure, and depth of insertion that compare favorably with double and single balloon enteroscopy. The strengths of spiral enteroscopy are rapid advancement in the small bowel and controlled, stable withdrawal that facilitates therapy. Future studies will be needed to compare competing technologies. Push enteroscopy is a readily available, safe and effective technique for detecting and treating proximal gut pathology. If performed without an overtube, complications are rare. Use of a dedicated push enteroscope with an overtube is generally reserved for specific indications in which a moderate increase in depth of insertion into the small bowel is required. When capsule endoscopy and deep small bowel enteroscopy are not available, push enteroscopy is a reasonable option with low risk and moderate yield. Push enteroscopy will remain an important part of the armamentarium of the modern endoscopist.

Spiral enteroscopy: a novel method of enteroscopy by using the Endo-Ease Discovery SB overtube and a pediatric colonoscope.

BACKGROUND: Pathologic diagnosis and therapeutic interventions on the small bowel have been difficult and challenging for gastroenterologists. In the last few years, significant advances have been made in this direction. New diagnostic and therapeutic modalities for visualizing the small bowel have been introduced. Furthermore, increased indications for small-bowel imaging and therapeutics have been recognized. However, the currently available methods have limitations, and development of newer, rapid, minimally invasive, safe, and readily available techniques is needed. OBJECTIVE: Our purpose was to evaluate the safety and efficacy of a novel method of spiral enteroscopy using a specialized overtube (Endo-Ease Discovery SB) with a pediatric colonoscope (PCF-140L). DESIGN: Case series. SETTING: Two international tertiary referral centers. PATIENTS: Twenty-seven adult patients with obscure GI bleeding were enrolled in this study. INTERVENTION: Spiral enteroscopy with the Endo-Ease Discovery SB overtube and a pediatric colonoscope. MAIN OUTCOME MEASUREMENTS: Depth of insertion, time of procedure, and complications. RESULTS: Average depth of insertion was 176 cm (range 80-340 cm) from ligament of Treitz, and average time of procedure was 36.5 minutes (range 90-65 minutes). Eleven patients had minor complications, which included minimal mucosal trauma and sore throat. LIMITATIONS: Small number of patients with a case series study design. CONCLUSIONS: Preliminary data suggest that use of Endo-Ease Discovery SB overtube for enteroscopy is a safe and effective technique for visualization of the small bowel.

[Auricular myiasis cause by Cochliomyia hominivorax (Diptera: Calliphoridae) (Coquerel, 1858)]. / Miasis auricular por Cochliomyia hominivorax (Diptera: Calliphoridae) (Coquerel, 1858).

We report a 37 years old male, coming from Paraguay, who consulted for tinnitus, hearing loss, foreign body sensation and pain in the left ear. He informed that a fly entered into his external auditive channel, five days before consulting. We observed the destruction of the tympanic membrane and 22 live larvae were extracted. Following the larval extraction, these injuries evolved to complete resolution. Larvae were identified as pertaining to the genus Cochliomyia hominivorax.

Quiste pilonidal: experiencia en el servicio / Pylonidal cyst: experience

En este trabajo, presentamos catorce casos (14) de quiste pilonidal, los cuales fueron sometidos íntegramente al tratamiento quirurgico, utilizando dos tecnicas operatorias. 1) Cierre primario; 2) Cierre por segunda intención. La finalidad de este trabajo, es demostrar las ventajas de la primera tecnica, que son menos días de internación, mejor cicatrización y pronto retorno a la vida laboral, sin recidiva alguna en nuestra experiencia

Punción aspirativa intraoperatoria del liquido biliar: informe preliminar

Los autores presentan los resultados preliminares de un estudio doble ciego prospectivo y randomizado realizado durante seis meses (de noviembre de 1988 a abril de 1989), en treinta pacientes con indicación de cirugía biliar, a fin de determinar la presencia o no de contaminación en vías biliares. Se practicó punción intraoperatoria de las vías biliares y el material obtenido fué sometido a examen directo, coloración de GRAM, cultivo en aerobiosis y anaerobiosis, y prueba de sensibilidad a los antibióticos y quimioterápicos. Se buscó determinar la necesidad o no del uso rutinario de antibióticos en pacientes sometidos a cirugía de vías biliares, utilizando como parámetro la presencia de bacterias en el material así obtenido. Los resultados indican que en el 61% de los casos la bilis no estaba contaminada siendo innecesaria la utilización rutinaria de antibióticos, práctica habitual en nuestro medio. Y que en pacientes mayores de 50 años sí debe hacerse profilaxis con antibióticos dado el alto índice de contaminación encontrado en estos pacientes