Toma de decisiones de encomienda y evaluación de las actividades profesionales confiables en la educación médica basada en competencias: una revisión de alcance y análisis temático / Entrustment decision-making and evaluation of entrustable professional activities in the competency- based medical education: a scoping review and thematic analysis

Introducción: La evaluación de las actividades profesionales confiables implica que el tutor tome decisiones de encomienda que posibiliten el desarrollo de competencias adecuadas de los futuros especialistas. Objetivo. El objetivo es conocer los componentes que sustentan la toma de decisiones de encomienda como herramienta de evaluación efectiva, segura y eficaz de las actividades profesionales confiables en la educación médica basada en competencias. Materiales y métodos: Se realizó una revisión sistemática en las bases de datos PubMed, BIREME-BVS y Web of Science. Se procedió al análisis y síntesis de los artículos, de acuerdo con la metodología JBI para las revisiones de alcance; el análisis se profundizó en otros artículos de revistas especializadas y citas bibliográficas relacionadas; y el manuscrito final se efectuó con base en las recomendaciones PRISMA-ScR. Resultados: La toma de decisiones de encomienda se centra en la relación tutor-estudiante, con base principalmente en la proactividad, la integridad, la capacidad y la humildad del estudiante, que confluyen en la confianza del tutor para sobrepasar la ‘zona de desarrollo próximo’ y alcanzar un siguiente nivel. Aunque eso signifique un determinado riesgo inicial sobre la seguridad de la atención médica, permite gradualmente generar la autonomía del estudiante. Conclusiones: No cabe duda de que la toma de decisiones de encomienda se basa en la confianza, la encomienda, la supervisión y la autonomía. Una escala retrospectiva-prospectiva que incluya la confianza-encomienda-supervisión-autonomía permite una adecuada evaluación de las actividades profesionales confiables y, por ende, la evaluación de las competencias.(AU)

Introduction: The evaluation of entrustable professional activities implies that the tutor makes assignment decisions that enable the development of appropriate competencies of future specialists. Aim. The aim of this work is to recognize the components that support entrustment decision making as an effective, safe and efficient evaluation tool of entrustable professional activities, in competency-based medical education. Materials and methods: A systematic review was carried out in the PubMed, BIREME-BVS and Web of Science databases. The analysis and synthesis of the articles was carried out in accordance with the JBI methodology for scoping reviews; and was further conducted including other articles from specialized journals and related bibliographic citations. The final manuscript was prepared based on the PRISMA-ScR recommendations.Results: Entrustment decision-making focuses on the tutor-student relationship, based mainly on the student’s proactivity, integrity, ability and humility, which converge in the tutor’s confidence to surpass the ‘zone of proximal development’ and reach the next level. Although this means a certain initial risk to the safety of medical care, it gradually generates the student’s autonomy. Conclusions: There is no doubt that entrustment decision-making is based on trust, entrustment, supervision and autonomy. A retrospective-prospective scale that includes trust-entrustment-supervision-autonomy allows for an adequate evaluation of entrustable professional activities and, therefore, the evaluation of competencies.(AU)

Effect of Bimaxillary Orthognathic Surgery on Pharyngeal Airway Volume / Efecto de Cirugía Ortognática Bimaxilar en el Volumen de la Vía Aérea Faríngea

SUMMARY: Subjects with maxillary skeletal classes II and III not only express alterations in the hard and soft maxillofacial tissues, but also in the morphology and dimensions of the upper airway. A small space in the upper airway has been associated with sleep disorders, such as snoring and mainly obstructive sleep apnea/hypopnea syndrome (OSAHS). Consequently, interest has increased due to the influence of orthognathic surgery in the airway space. Although there are studies in the literature that have compared upper airway spaces, most have evaluated the changes using two-dimensional images, mainly lateral skull X-rays. The present study aimed to determine the airway volume in subjects with skeletal classes II and III who underwent bimaxillary orthognathic surgery. 80 CBCT exams from 40 subjects obtained before and 6 months after surgery were used. There were 20 class II and 20 class III subjects. For the volumetric analysis, a 3D rendering of the upper airway was made in previously established segments, and then the airway volume was calculated using the 3D Slicer® software version 4.11 (Slicer, USA). The statistical analysis by t-test of related samples revealed statistically significant volumetric increases in the nasopharynx, laryngopharynx, and total volume in class II patients. However, in class III patients, there were significant increases in the nasopharynx and total volume, while the volume was maintained in the oropharynx and laryngopharynx.

Sujetos con clases esqueletales II y III maxilares, no solamente expresan alteraciones en los tejidos duros y blandos maxilofaciales, sino también en la morfología y dimensiones de la vía aérea superior. Un espacio reducido a nivel de la vía aérea superior se asocia a trastornos del sueño como ronquidos y principalmente el síndrome de apnea/hipoapnea obstructiva del sueño (AOS); debido a esto, ha aumentado el interés por la influencia de la cirugía ortognática en el espacio de la vía aérea. Si bien existen en la literatura estudios que han comparado los espacios de la vía aérea superior, la mayoría de los estudios han evaluado los cambios utilizando imágenes bidimensionales, principalmente radiografías laterales de cráneo. El objetivo del presente estudio fue determinar el volumen de la vía aérea en sujetos con clases esqueletales II y III sometidos a cirugía ortognática bimaxilar. Se utilizaron 80 exámenes CBCT pertenecientes a 40 sujetos obtenidos previo a la cirugía y 6 meses después de realizada. Veinte sujetos clase II y 20 clase III. Para el análisis volumétrico se realizó un renderizado 3D de la vía área superior en segmentos previamente establecidos y posteriormente se calculó el volumen de dicha vía aérea con la utilización del software 3D Slicer ®versión 4.11 (Slicer, USA). El análisis estadístico realizado por t-test de muestras relacionadas, arrojó en pacientes clase II aumentos volumétricos estadísticamente significativos en nasofaringe, laringofaringe y volumen total. Mientras que en pacientes clase III, se observó aumentos significativos en Nasofaringe y volumen total y mantención de volumen en orofaringe y laringofaringe.

An Overview of Clinical Conditions and a Systematic Review of Personalized TMJ Replacement.

The temporomandibular joint (TMJ) is a complex structure in the cranio-maxillomandibular region. The pathological changes of the joint cause deficiencies at different levels, making its replacement necessary in some cases. The aim of this article is to analyze the current indications, treatment and criteria, and follow-up using a systematic review and case series. A systematic review was carried out, identifying the indications for the use of a customized TMJ prosthesis and evaluating criteria and validation in the international literature. After review and exclusion, 8 articles were included with a minimum follow-up of 12 months. The age of the subjects was between 18 and 47 years old. In 226 patients, 310 TMJ prostheses were installed, 168 bilaterally and 142 unilaterally. In most of the articles, a good condition in the follow-up was observed, with a reduction in pain and better conditions of mandibular movement and function. TMJ prosthesis and replacement is a protocolized, defined, stable, and predictable procedure. Indications and criteria must be evaluated by specialists and patients related to the pathology involved in TMJ deformity or degeneration. Randomized research with an accurate diagnosis and follow-up is necessary to obtain the best indication for this treatment.

The Influence of Surface Treatment on Osseointegration of Endosteal Implants Presenting Decompressing Vertical Chambers: An In Vivo Study in Sheep.

PURPOSE: To qualitatively and quantitatively evaluate histologic osseointegration parameters of implants designed with decompressing vertical chambers between the threads with two different surface treatments (TiO2 blasting + maleic acid vs TiO2 blasting + maleic + HCl) in a large translational animal model at 3 and 6 weeks in vivo. MATERIALS AND METHODS: Nine female sheep were used, and 72 implants with trapezoidal threads and decompressing vertical chambers of 0.6 mm in diameter and 0.2 mm in depth were placed in the ilium crest. After 3 and 6 weeks, the animals were euthanized, and biomechanical and histomophometric analyses were performed. RESULTS: Survey histologic evaluation indicated intimate contact between the bone and the implants independent of surface treatment at both times in vivo. Bone formation at both time points depicted an intramembranous-type healing pattern between the implant threads. The mean removal torque values for all groups showed a relative increase in removal torque from 3 to 6 weeks. In terms of bone area fraction occupancy analysis, significant differences were found at 6 weeks between surface treatments (P = .046), where the experimental surface yielded higher degrees of bone area fraction occupancy. CONCLUSION: Conical implants with decompressing vertical chambers between threads presented similar osseointegration parameters regarding bone-toimplant contact and torque-out test values irrespective of surface treatment. However, shifting from a minimally rough to a moderately rough surface (experimental surface with supplemental acid-etching) resulted in significantly improved bone area fraction occupancy at 6 weeks.

TMJ Position in Symmetric Dentofacial Deformity.

The aim of this research was to analyze the facial class, presence of malocclusion, and the mandibular plane and to relate this to the mandibular condyle position. A cross-sectional study in subjects under analysis for orthognathic surgery was done. The mandibular plane, the gonial angle, and the molar class were included to compare the coronal and sagittal position of the condyle and the joint space observed in the CBCT. The measurements were obtained by the same observer at an interval of two weeks. In addition, the Spearman test was performed to determine the correlation using a p value < 0.05 to observe any significant differences. Eighty-nine male and female subjects (18 to 58 years old, 24.6 ± 10.5) were included. In the coronal section, subjects with CIII had a greater mediolateral distance (MLD, p = 0.0001) and greater vertical distance (SID, p = 0.0001) than subjects with CII. In terms of the skeletal class and the mandibular plane, it was observed that subjects in the CII group had a greater mandibular angle (open angle) (p = 0.04) than the CII group and was related to the anterior position of the condyle. The most anterior condylar position was observed in the CII group (p = 0.03), whereas a posterior condylar position was significant in CIII subjects (p = 0.03). We can conclude that the sagittal position of the TMJ was related to the mandibular plane and the skeletal class showing a higher mandibular angle and most anterior position of the condyle in CII subjects and a lower mandibular angle and most posterior position of the condyle in CIII subjects. The implications for surgical treatment have to be considered.

Influencia de diferentes materiales de relleno en alvéolos post exodoncia de ratas ovariectomizadas (OVX) / Influence of different graft materials on post extraction sockets of ovariectomized rats (OVX)

RESUMEN: El objetivo del presente estudio fue establecer la influencia de diferentes materiales en el proceso de regeneración ósea de alveolos post exodoncia de ratas hembra adultas ovariectomizadas (OVX). Para ello, se utilizaron 40 ratas sprague dawley, divididas en grupo experimental (OVX) (n=20) y grupo control (Sin ovariectomía) (n=20). Todas las ratas del grupo experimental fueron sometidas a ovariectomía bilateral para simular un estado de osteoporosis inducida por déficit de estrógeno. Posterior a 12 semanas post OVX, las ratas de ambos grupos fueron divididas en 4 subgrupos, en los cuales fue extraído el primer molar superior derecho de cada rata. Posteriormente, las terapias realizadas en los alveolos post-exodoncia fueron: A: (N=5) Alveolo no rellenado para ser utilizado como control negativo. B: (N=5) Aplicación de injerto bifásico (HA+BTCP). C: (N=5) Aplicación de PRF. D: Aplicación de una combinación de injerto bifásico + PRF. Luego de tres semanas se realizó la eutanasia de los animales y obtención de las muestras para los análisis respectivos. Todos los animales sobrevivieron al final del estudio sin ninguna complicación postoperatoria. Los resultados cuantitativos del área ósea interradicular del segundo molar superior, mostraron diferencias estadísticamente significativas entre grupo control y grupo OVX. Mientras que no se observaron diferencias en la descripción histológica ni en el análisis cuantitativo de fibras colágenas tipo I y III. Es posible concluir que el modelo de osteoporosis inducida por déficit de estrógeno modificaría también la microarquitectura ósea de la Maxila. No obstante, nuevos estudios son necesarios para continuar con el estudio de biomateriales para regeneración ósea en modelos de osteoporosis inducida.

SUMMARY: The aim of the present study was to establish the influence of different materials on the process of bone regeneration in post-extraction sockets of ovariectomized (OVX) adult female rats. For this, 40 Sprague Dawley rats were used, divided into an experimental group (OVX) (n=20) and a control group (without ovariectomy) (n=20). All rats in the experimental group underwent bilateral ovariectomy to simulate a state of estrogen deficiency osteoporosis. After 12 weeks post OVX, rats from both groups were divided into 4 subgroups, in which the upper right first molar of each rat was extracted. Subsequently, the therapies performed in the post-extraction sockets were A: (N=5) Unfilled alveolus to be used as a negative control. B: (N=5) Biphasic graft application (HA+BTCP). C: (N=5) PRF application. D: Application of a combination of biphasic graft + PRF. After three weeks, the animals were euthanized, and the samples were obtained for the respective analyses. All animals survived to the end of the study without any postoperative complications. The quantitative results of the interradicular bone area of ??the upper second molar showed significant differences between the control group and the OVX group. While no differences were observed in the histological description or in the quantitative analysis of collagen fibers type I and III. It is possible to conclude that the model of osteoporosis induced by estrogen deficiency would modify the bone microarchitecture of the Maxilla. However, new studies are necessary to continue with the study of biomaterials for bone regeneration in models of induced osteoporosis.

Effects of a local single dose administration of growth hormone on the osseointegration of titanium implants

Background: The aim of the present study was to evaluate the effect of different concentrations of growth hormone (GH) on endosteal implant’s surface at the early stages of osseointegration. Material and Methods: Sixty tapered acid-etched titanium implants were divided into four groups: i) Collagen, used as a control group; and three experimental groups, where after collagen coating, GH was administered directly to the surface in varying concentrations: ii) 0.265 mg, iii) 0.53 mg, and iv) 1 mg. Implants were placed in an interpolated fashion in the anterior flange of C3, C4 or C5 of 15 sheep with minimum distance of 6 mm between implants. After 3-, 6- and 12-weeks of healing samples were harvested, histologically processed, qualitatively and quantitatively assessed for bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO). Results: Statistical analysis as a function of time in vivo and coating resulted in no significant differences for BIC and BAFO at any evaluation time point. Histological evaluation demonstrated similar osseointegration features for all groups with woven bone formation at 3 weeks and progressive replacement of woven for lamellar bone in close contact with the implant surface and within the implant’s threads. Conclusions: A single local application of growth hormone to the surface of titanium implants did not yield improved implant osseointegration independent of healing time.(AU)

Cambios en la vía aérea después de cirugía ortognática bimaxilar / Airway change after bimaxillary orthognathic surgery

RESUMEN: La cirugía ortognática se realiza en sujetos con algún tipo de alteración esqueletal. Los movimientos maxilo mandibulares tienen impacto en la vía aérea (VA) y este aspecto se debe incorporar en la planificación quirúrgica. El objetivo de esta investigación fue determinar los cambios generados en la VA después de realizada la cirugía ortognática. Se realizó un estudio piloto incluyendo 51 sujetos con deformidad facial de clase II y clase III; se incluyeron en base al estudio del ángulo ANB y el tipo de oclusión dentaria. Se realizaron estudios con tomografía de haz cónico identificando el volumen máximo en la vía área y las áreas mínimas y máximas; además se incluyó la posición del hueso hioide y la inclinación del plano mandibular para relacionar con la morfología de la VA; para definir significancia estadística se estableció un valor de p<0,05 incluyendo las pruebas T de student y T test. Los resultados indicaron que los sujetos clase II aumentaron significativamente el volumen y áreas máximas y mínimas de la VA; los sujetos de clase III esqueletal no presentaron diferencias significativas entre la etapa pre y post quirúrgica; el hueso hioides se presentó significativamente más anterior en ambos en casos de clase II y clase III. Es posible concluir que la VA mejora sustancialmente en sujetos con clase esqueletal facial tipo II y que se mantiene sin cambios en sujetos con clase facial tipo III.

SUMMARY: Orthognathic surgery is performed in subjects with some type of skeletal alteration. Maxillomandibular movements have an impact on the airway (AW) and this aspect must be included into surgical planning. The aim of this research is to determine the changes in the AW after orthognathic surgery. A pilot study was conducted including 51 subjects with class II and class III facial deformity; they were included using the ANB angle and the type of dental occlusion. Cone beam computed tomography were performed showing the maximum volume in the airway and the minimum and maximum areas; in addition, the position of the hyoid bone and the angle of the mandibular plane were included to relate it to the morphology of the AW; to define statistical significance, a value of p<0.05 was established, including the student's t-test and the t-test. The results showed that class II subjects significantly increased the volume and maximum and minimum areas of the AW; skeletal class III subjects did not presented significant differences between the pre- and post-surgical stage; the hyoid bone was in an anterior position in both class II and class III cases. It is possible to conclude that AW improves substantially in subjects with facial class II and remains unchanged in subjects with facial class III.

Osseodensification Versus Subtractive Drilling Techniques in Bone Healing and Implant Osseointegration: Ex Vivo Histomorphologic/Histomorphometric Analysis in a Low-Density Bone Ovine Model.

PURPOSE: The aim of this study was to qualitatively and quantitatively assess the effect of osteotomy preparation by conventional, subtractive, or osseodensification instrumentation on osteotomies, treated with or without endosteal implants, and healing capacity. MATERIALS AND METHODS: Seven sheep were used, and 56 osteotomies were made in the left and right ilium of the sheep (n = 8/sheep [4 per side/time point (3 and 6 weeks)]). Two different instrumentation techniques were used: (1) conventional/regular drilling in a three-step series of a 2-mm pilot and 3.2-mm and 3.8-mm twist drills and (2) osseodensification drilling with a Densah Bur 2.0-mm pilot and 2.8-mm and 3.8-mm multi-fluted tapered burs. Drilling was performed at 1,100 rpm with saline irrigation. RESULTS: Qualitative histomorphometric evaluation of the osteotomies after 3 and 6 weeks did not indicate any healing impairment due to the instrumentation. In all samples, histologic examination suggested bone remodeling and growth (empty and treated with an implant), irrespective of preparation technique. Osteotomies prepared using the osseodensification instrumentation showed the existence of bone chips autografted into the trabecular spaces along the length of the osteotomy wall. CONCLUSION: The osseodensification group yielded higher osseointegration rates, as distinguished through qualitative assessment, bone-to-implant contact, and bone-area-fraction occupancy, indicating an increased osteogenic potential in osteotomies prepared using the osseodensification technique.

Morfología ósea facial en cirugía ortognática. ¿existe tendencia hacia el avance facial? / Facial morphology in orthognathic surgery: is there a facial advance trend?

RESUMEN: El objetivo de esta investigación fue determinar los movimientos preferidos en maxila y mandíbula para obtener normalidad en morfología facial utilizando técnicas de superimposición en análisis 3D. Se realizó un estudio descriptivo para evaluar el desplazamiento óseo bimaxilar y del hueso hioides en sujetos clase facial tipo II y clase facial tipo III sometidos a cirugía ortognática. Para la superimposición se utilizó como puntos fijos Nasion - Silla - Porion y la sutura cigomática-maxilar. Estos puntos se superpusieron en CBCT pre quirúrgico y postquirúrgico y se evaluó el desplazamiento de la espina nasal anterior, Punto A, Punto B, mentón y del hueso hioides. Para la evaluación y comparación de las variables continuas antes y después de la cirugía ortognática se utilizó la prueba T de Student. Para la correlación entre las variables, se utilizó el Test de Spearman considerando un valor p<0,05 como diferencia significativa. 44 sujetos de entre 18 y 40 años de ambos sexos, fueron incluidos en esta investigación. En el 90 % de los sujetos se realizó un movimiento sagital de avance de la maxila. El movimiento sagital de avance mandibular se realizó en el 100 % de los sujetos con clase facial tipo II, mientras que el 100 % de los sujetos con clase facial tipo III se realizó se le retroceso mandibular. El hueso hioides presentó un avance en 26 de los 27 sujetos con clase facial tipo III. Es posible concluir que existe una tendencia al avance maxilar independiente de la deformidad facial.

ABSTRACT: The objective of this research was to determine the preferred movements in the maxilla and mandible to obtain normality in facial morphology using superimposition techniques in 3D analysis. A descriptive study was carried out to evaluate bimaxillary bone displacement and hyoid bone in subjects facial class II and facial class III undergoing orthognathic surgery. were used as fixed points for superimposition: Nasion (N) - Silla (S) - Porion (Po) and the zygomatic-maxillary suture (Z). These points were superimposed in pre-surgical and post- surgical CBCT and was evaluated to displacement of the anterior nasal spine, Point A, Point B, Chin and the hyoid bone. For the evaluation and comparison of continuous variables before and after orthognathic surgery, was used the Student's t test. For the correlation between the variables, the Spearman test is used, considering a p value <0.05 as a significant difference. 44 subjects between 18 and 40 years old of both sexes were included in this research. A 90% of subjects a was performed a maxillay sagittal movement. The sagittal movement of mandibular advancement was performed in 100% with facial class type II, while 100 % of the subjects with with facial class type III had a mandibular recession. The hyoid bone advanced in 26 of the 27 subjects with facial class type II. It is possible to conclude that there is a tendency for maxillary advancement, independent of facial deformity.

Effect of supplemental acid-etching on the early stages of osseointegration: A preclinical model.

PURPOSE: To evaluate the effect of two surface modifications on early osseointegration parameters of conical implants in a translational pre-clinical model. MATERIALS AND METHODS: Conical implants with progressive trapezoidal threads and healing chambers were evaluated consisting of two different surface conditions: 1) Implacil surface (IMP Sur), and 2) Implacil surface + Supplemental Acid-etching (IMP Sur + AE). Surface characterization comprised of the evaluation of roughness parameters (Sa, Sq and Sdr), surface energy and contact angle. Subsequently, implants were installed in the ilium crest of nine female sheep (weighing ~65 kg). Torque out, histological and histomorphometric analyses were conducted after 3 and 6 weeks in-vivo. The percentage of bone to implant contact (%BIC) and bone area fraction occupancy within implant threads (%BAFO) were quantified, and the results were analyzed using a general linear mixed model analysis as function of surface treatment and time in-vivo. RESULTS: Supplemental acid etching significantly increased Sa and Sq roughness parameters without compromising the surface energy or contact angle, and no significant differences with respect to Sdr. Torque-out testing yielded significantly higher values for IMP Sur + AE in comparison to the IMP Sur at 3- (62.78 ± 15 and 33.49 ± 15 N.cm, respectively) and 6-weeks (60.74 ± 15 and 39.80 ± 15 N.cm, respectively). Histological analyses depicted similar osseointegration features for both surfaces, where an intramembranous-type healing pattern was observed. At histomorphometric analyses, IMP Sur + AE implants yielded higher values of BIC in comparison to IMP Sur at 3- (40.48 ± 38 and 27.98 ± 38%, respectively) and 6-weeks (45.86 ± 38 and 34.46 ± 38%, respectively). Both groups exhibited a significant increase in %BAFO from 3 (~35%) to 6 weeks (~44%), with no significant differences between surface treatments. CONCLUSION: Supplemental acid-etching and its interplay with implant thread design, positively influenced the BIC and torque-out resistance at early stages of osseointegration.

Growth and metabolic responses to methyl viologen (1,1'-dimethyl - 4,4'-bipyridinium dichloride) on Chlorella vulgaris.

Aquatic environments are especially susceptible to being contaminated by pesticides used in agricultural fields. Methyl viologen (MV) is an herbicide with high effectiveness for the control of unwanted land plants; however, it also has a high toxicity towards the algae in the aquatic environment. The objective of this work was to describe the effect of MV on photosynthetic metabolism and its relationship with respiration, growth and the content of photosynthetic pigments of Chlorella vulgaris. The cultures of C. vulgaris were exposed for 72 h at different concentrations of methyl viologen. The results show that growth, pigment content and metabolic activity decrease as the concentration of MV increases. Analysis of the photochemical activity indicates that MV produces an inhibition of electron transport between quinone A and quinone B of photosystem II. The inhibition of photosynthetic electron transport is directly related to the reduction of metabolic activity and cell growth. The results found in this research show that methyl viologen can be a toxic pollutant for primary producers in aquatic environments.

Comparison of Surface Treatments of Endosteal Implants in Ovariectomized Rabbits.

PURPOSE: The aim of this work was to evaluate osseointegration of endosteal implants with two different surface treatments at early stages (~3 weeks) in the tibia of healthy and ovariectomized rabbits. MATERIALS AND METHODS: The study comprised 10 adult New Zealand female rabbits (Oryctolagus cuniculus; 6 months and 3.0 ± 0.5 kg). Five animals were subjected to bilateral ovariectomy to mimic osteoporotic-like conditions, and the remaining rabbits (n = 5) served as the healthy control group. After 3 months, specimens from the ovariectomized and control groups were subject to implant placement in both tibiae, using two different types of surface treatment. A total of 36 implants were placed, n = 18 acid-etched and n = 18 anodized. After 3 weeks, euthanasia of the animals was performed, and samples were obtained for processing. Bone-to-implant contact and bone area fraction occupancy were quantified to evaluate the osseointegration parameters around the implant surface and within the thread area, respectively, and nanoindentation tests were performed to determine elastic modulus and hardness of the new bone. Both analyses were performed on the entire implant (total), as well as individually within the cortical and bone marrow cavity area. RESULTS: All animals were evaluated with no signs of infection or postoperative complications. The total bone-to-implant contact and bone area fraction occupancy results, independent of surface treatment, yielded significant differences between the ovariectomized and control groups (P = .002 and P < .001, respectively). In the marrow cavity, analyzing the surface treatments independently as a function of bone condition, the only differences detected were in the anodized treatment (P = .04). Regarding the elastic modulus, differences were detected only with the anodized implants between the ovariectomized and control groups (P = .015). CONCLUSION: At 3 weeks after implant placement, there were better osseointegration values of the implants in the healthy control group compared with the ovariectomized group independent of surface treatment. Also, specifically in the medullary region of the rabbit tibia, the acid-etched implants had more uniform osseointegration values in conditions of low-quality bone in comparison to the anodized implants, histomorphometrically and biomechanically.

Análisis descriptivo de un modelo de osteoporosis inducida en ratas (Rattus norvegicus) / Descriptive analysis of an induced osteoporosis model in rats (Rattus norvegicus)

RESUMEN: El objetivo del presente estudio fue realizar un análisis histopatológico de un modelo animal en ratas, que simule las características observables en huesos de pacientes con osteoporosis. Para ello, se utilizaron 10 ratas hembras (Rattus norvegicus) Sprague Dawley de 12 semanas de desarrollo y aproximadamente 200-250 g. De las cuales, a 5 se le realizó ovariectomía (OVX) bilateral, mientras que las 5 restantes fueron utilizadas como control. Posterior a 12 semanas de realizadas las ovariectomías en el grupo experimental, se realizó la eutanasia de los animales y la obtención de ambos fémur, los cuales fueron posteriormente seccionados para procesar su porción distal para su procesamiento histológico de rutina. Todos los animales sobrevivieron al final del estudio sin ninguna complicación postoperatoria, las imágenes histológicas evidenciaron en el grupo experimental (OVX), una disminución del grosor del hueso cortical, mayor cantidad de hueso esponjoso, pérdida de la continuidad de periostio y endostio alrededor de la matriz ósea además de mayor cantidad de tejido adiposo en la médula ósea, al ser comparados con el grupo control. Se puede concluir que a las 12 semanas post ovariectomía se observa un fenotipo histopatológico compatible con características oseteoporóticas en ratas adultas.

SUMMARY: The aim of the present study was to conduct a histopathological analysis of an animal model in rats, which simulates the characteristics observable in bones of patients with osteoporosis. To this end, 10 female rats (Rattus norvegicus) Sprague Dawley of 12 weeks of development and approximately 200-250 g were used. Of these, 5 underwent bilateral ovariectomy (OVX), whereas the remaining 5 were used as control. After 12 weeks of ovariectomy in the experimental group, the animals were euthanized and the two femurs were collected, which were then sectioned to process their distal portion. All the animals survived at the end of the study without any signs of postoperative complications. In the experimental group (OVX), the histological images showed a decrease in the thickness of the cortical bone, a greater amount of cancellous bone, loss of the continuity of the periosteum and endostium around the bone matrix in addition to a greater amount of adipose tissue in the bone marrow, when compared with the control group. It can therefore be inferred that a histopathological phenotype can be found at 12 weeks post- ovariectomy that would be consistent with osteoporotic characteristics in adult rats.

Effect of Surgical Instrumentation Variables on the Osseointegration of Narrow- and Wide-Diameter Short Implants.

PURPOSE: The aim of the present study was to systematically analyze how a multifactorial surgical instrumentation approach affects osseointegration on both narrow-diameter and wide-diameter short implants. MATERIALS AND METHODS: Twelve skeletally mature female sheep were used in the study along with 144 plateau-root-form healing chamber titanium (Ti-6Al-4V) implants (Bicon LLC, Boston, MA), evenly distributed between narrow (3.5 mm) and wide (6.0 mm) diameters. The presence or the absence of irrigation, different drilling speeds, and 2 time points quantifying bone-implant contact (BIC) and bone area fraction occupancy (BAFO) to evaluate the osteogenic parameters around the implants. RESULTS: There were no signs of inflammation, infection, or failure of the implants observed at either healing period. The narrow 3.5-mm implant, at 6 weeks, yielded significant differences in terms of BIC at a drilling speed of 50 rotations per minute (RPM), with higher values of the samples using irrigation (30.6 ± 6.1%) compared with those without (19.7 ± 6.1%). No statistical differences were detected for 500 and 1,000 RPM with or without irrigation. The wide 6-mm diameter implant showed differences with respect to drilling speed, 500 and 1,000 RPM, with higher values associated with samples subjected to irrigation. BAFO results, for both diameters, only detected statistical differences between the 2 times (3 vs 6 weeks); no statistical differences were detected when evaluating as a function of time, drilling speed, and irrigation. CONCLUSIONS: Surgical instrumentation variables (ie, drilling speed [RPM] and irrigation) yielded to be more of an effect for BIC at longer healing time (6 weeks) for the wider implants. Furthermore, deploying narrow or wide plateau-root-form implants, where conditions allow, has shown to be a safe alternative, considering the high BIC and BAFO values observed, independent of irrigation.

Nasal septum deviation and inferior nasal concha bone hypertrophy in class III facial deformity / Desviación del septum nasal e hipertrofia de la concha nasal inferior en deformidad facial clase III

SUMMARY: The aim of this research was to analyze the morphology of the nasal septum and inferior nasal concha bone in class III facial deformities prior to orthodontic treatment in orthognathic surgery candidates. 40 subjects were included in this research. The inclusion criteria were an Angle class III, negative overjet and SNA angle less than 80º. Patients with facial asymmetry, facial trauma or who had undergone maxillofacial or ENT procedures were excluded. CBCT images were obtained for all the patients and the nasal septum deviation, morphology of inferior nasal concha bone and ostium of the maxillary sinus were analyzed and related to the complexity of the facial deformity expressed by the ANB angle and dental relations. The measurement was standardized by ICC and the data was analyzed using a chi square test and Spearman's coefficient with a p value < 0.005 for statistical significance. Nasal septal deviation was observed in 77.5 %. The deviation angle was 13.28º (±4.68º) and the distance from the midline to the most deviated septum was 5.56 mm (±1.8 mm) with no statistical relation to the complexity of the facial deformity. The deviated nasal septum showed inferior nasal concha bone hypertrophy on the concave side of the nasal septum deviation (p=0.049). The open or closed condition of the maxillary sinus ostium was not related to any conditions in the septum or complexity of the facial deformity. Inferior nasal concha bone hypertrophy could be related to nasal septal deviation. The nasal condition in a class III facial deformity could not differ from the general population; careful in orthognathic surgery as to be assume in the Le Fort I Osteotomy and nasal approach related to nasal septum deviation and inferior nasal concha bone.

RESUMEN: El objetivo de esta investigación fue analizar la morfología del septum y la concha nasal inferior en sujetos con deformidad facial clase III previo al tratamiento de ortodoncia preparatorio para cirugía ortognática. Fueron incluidos 40 sujetos en esta investigación. Los criterios de inclusión fueron la de presentar una clase III de Angle, overjet negativo y ángulo SNA menor que 80º. Sujetos con asimetría facial, trauma facial o quienes presentaron algún tipo de procedimiento maxilofacial o de otorrinolaringología fueron excluidos. Tomografía computadorizada cone beam (CBCT) fueron obtenidas para todos los sujetos donde le morfología del septum nasal, morfología de la concha nasal inferior y el ostium del seno maxilar fueron analizados y relacionados con la complejidad de la deformidad facial expresada como ángulo ANB y relaciones dentales. Las medidas fueron estandarizadas por el ICC y los datos fueron analizados utilizando la prueba chi cuadrado y coeficiente de Spearman con un valor de p<0,05 para obtener relaciones significativas. La desviación del septum nasal se observó en el 77,5 %; el ángulo de desvío fue de 13,28º (±4,68º) y la distancia de desvío del septum desde la línea media fue de 5,56 mm (±1,8 mm) sin diferencias estadísticas en relación a la complejidad de la deformidad. El desvío de septum nasal demostró hipertrofia de la concha nsal inferior en el lado cóncavo del septum desviado (p=0,049). La condición de ostium abierto o cerrado no fue relacionado con ninguna condición del septum nasal o complejidad de la deformidad facial. La hipertrofia de la concha nasal inferior se relacionó con el desvío de septum nasal. La condición nasal en deformidad facial de clase III no es diferente de la observada en la población general; cuidados deben ser realizados en cirugía ortognática para el desarrollo de la osteotomía de Le Fort I y aproximación nasal en relación al desvío de septum y probable alteración de la concha nasal inferior.

PLA/PGA and its co-Polymers in Alveolar Bone Regeneration. A Systematic Review / PLA/PGA y sus Copolímeros en Regeneración Ósea Alveolar. Una Revisión Sistemática

ABSTRACT: The aim of this research was to perform a systematic review to identify the most frequent uses of PLA/ PGA in alveolar bone regeneration and their results. A study was designed to answer the question: What are the most frequent uses of PLA/PLGA and their copolymers in alveolar bone regeneration?. A systematic search was done on MEDLINE, EMBASE and LILACS from April 1993 to December 2017. The search string used on MEDLINE was: (((polylactic acid) OR PLA) OR PLA-based copolymers) OR PLA blends) OR PLA scaffolds)) AND ((("Bone Regeneration"[Mesh]) OR bone regeneration) OR guided bone regeneration). The search was complemented by a manual review of the references from the articles included. Most of the studies selected were weak and, regarding the most frequent uses of PLA/PGA, 13 studies used it as a resorbable membrane, two as an absorbable mesh, one as an absorbable screw and three as filling material. Based on our results, the authors consider that PLA/PGA requires a delicate relation between the mechanical resistance and the degradation process. PLA/PGA does not interrupt bone regeneration; however, the influence in cellular events related to bone regeneration and later osseointegration have not been identified.

RESUMEN: El objetivo de esta revisión fue realizar una revisión sistemática de la literatura para identificar los usos más frecuentes de PLA/PGA en regeneración ósea en área maxilofacial y sus resultados. Se diseñó un estudio para responder a la pregunta: ¿Cuáles son los usos más frecuentes de PLA/PLGA y sus copolímeros en regeneración ósea en el sector maxilofacial?. Los estudios seleccionados fueron en su mayoría débiles y sobre los usos más frecuentes de PLA/PGA, 13 estudios lo utilizaron como membrana reabsorbible, 2 estudios como malla absorbible, un estudio como tornillo absorbible y 3 estudios como material de relleno. En base a nuestros resultados, los autores estiman que PLA/PGA requiere una delicada relación entre la resistencia mecánica que ofrece y la degradación que se produce; PLA/ PGA no interrumpe la regeneración ósea, sin embargo, no se ha identificado la potencialidad o influencia que presenta en los eventos celulares de la regeneración y posterior oseointegración.

Morphological Analysis of the Human Maxillary Sinus Using Three-Dimensional Printing.

BACKGROUND: The maxillary sinus (MS) is described as a pyramid-shaped cavity of the maxilla. AIM: The aim of this research is to present a strategy for morphological analysis of the MS using three-dimensional (3D) printing acquired through cone-beam computed tomography images. MATERIAL AND METHODS: A cross-sectional exploratory, single-blind study was conducted, including 24 subjects. MSs were reconstructed, and 3D virtual modeling was done bilaterally, obtaining 48 physical models generated on a 3D printer. The statistical analysis used tests of normality and tests using a value of P < 0.05 to establish statistical significance. RESULTS: The mean of the MS volume was 15.38 cm3 (±6.83 cm3). The minimum volume was 5.4 cm3 and the maximum was 30.8 cm3. In a bilateral comparison of the right and left volume of the same individual, there were no significant differences (P = 0.353). In relation to the morphology of the MSs, the most prevalent was pyramidal with a square base with a prevalence of 66.7%. Related to gender, significant differences were observed only for the left volume (P = 0.009), with the mean volume being significantly greater in the men (19.69 cm3) than in the women (12.28 cm3). CONCLUSION: 3D printing of the MS permitted the more precise observation of anatomical features that cannot be seen on a 2D screen. A classification is presented that allows an analysis of sinus morphology, although it is necessary to conduct studies with larger samples to obtain more conclusive results.

Three-dimensional analysis of nasolabial soft tissues while smiling using stereophotogrammetry (3dMDTM) / Análisis tridimensional de los tejidos blandos nasolabiales en sonrisa utilizando estereofotogrametría (3dMDTM)

SUMMARY: The nasolabial region is the central esthetic unit of the face and is considered one of the most important determinants of the facial esthetic. The facial morphometry of soft tissues is a very important tool in facial surgery. Advances have been made recently in the capture and analysis of 3D images, which offer great development potential in the diagnosis and treatment of facial deformities. The aim of this study was to characterize the nasolabial region of patient candidates for orthognathic surgery using 3D facial captures. A study was conducted to characterize the width of the nasal base and the nasolabial angle in adult patients through 3D photographs. 30 subjects were included, taking two 3D photos each, one in a resting position and the other smiling. The three-dimensional capture was done with the 3dMDface System. The measurements were taken with the 3dMD Vultus software. The length of the alar base was an average of 34.3 ± 2.6 mm at rest, and 39.1 ± 2.9 mm smiling. The mean of the nasolabial angle was 104.6 ± 9.6° at rest and 105.4 ± 14.3º smiling. Additionally, the distance of the alar base smiling compared to its distance at rest increased an average of 4.83 mm, whereas the nasolabial angle smiling increased an average of 0.8º compared to at rest. In this study, the nasolabial angle did not present any significant changes so that its assessments in the case of facial modifications can be standard; the width of the nasal base is significantly modified with the smile and thus a more intense study of any type of modification in this area is required.

RESUMEN: La región nasolabial es la unidad estética central de la cara y se considera uno de los determinantes más importantes de la estética facial. La morfometría facial en tejidos bandos, es una herramienta de gran importancia en Cirugía Facial. En el último tiempo, se han realizado avances en captura y análisis de imágenes 3D, las cuales ofrecen un gran potencial de desarrollo en el diagnóstico y tratamiento de las deformidades faciales. El objetivo de éste trabajo fue caracterizar mediante capturas faciales 3D la región nasolabial de pacientes candidatos a cirugía ortognática. Se realizó un estudio para caracterizar a través de fotografías tridimensionales de pacientes adultos el ancho de la base nasal y el ángulo nasolabial. Se incluyeron 30 sujetos, tomando 2 fotografías 3D a cada uno, una en posición de reposo y otra en sonrisa. Se realizó la captura tridimensional con la camara facial 3dMDface System. Las mediciones fueron realizadas con el software 3dMD Vultus. La longitud de base alar en reposo, fue en promedio de 34,3 ± 2,6 mm, y de 39,1 ± 2,9 mm, en sonrisa. Por otra parte, la media del ángulo nasolabial en reposo fue de 104,6 ± 9,6° y en sonrisa, de 105,4 ± 14,3º. Por otro lado, la distancia de la base alar en sonrisa respecto a su distancia en reposo, aumentó un promedio de 4,83 mm, mientras que el ángulo nasolabial en sonrisa, aumentó en promedio 0,8º respecto a la posición de reposo. En esta investigación, el ángulo nasolabial no presentó cambios significativos de forma que su valoración frente a modificaciones faciales puede ser estándar; el ancho de base nasal se modifica significativamente con la sonrisa de forma que su estudio debe ser más agudo frente a cualquier tipo de modificación en esta zona.