Towards an optimal design of a functionally graded porous uncemented acetabular component using genetic algorithm.

Generation of polyethylene wear debris and peri­prosthetic bone resorption have been identified as potential causes of acetabular component loosening in Total Hip Arthroplasty. This study was aimed at optimization of a functionally graded porous acetabular component to minimize peri­prosthetic bone resorption and polyethylene liner wear. Porosity levels (porosity values at acetabular rim, and dome) and functional gradation exponents (radial and polar) were considered as the design parameters. The relationship between porosity and elastic properties were obtained from numerical homogenization. The multi-objective optimization was carried out using a non-dominated sorting genetic algorithm integrated with finite element analysis of the hemipelvises subject to various loading conditions of common daily activities. The optimal functionally graded porous designs (OFGPs -1, -2, -3, -4, -5) exhibited less strain-shielding in cancellous bone compared to solid metal-backing. Maximum bone-implant interfacial micromotions (63-68 µm) for OFGPs were found to be close to that of solid metal-backing (66 µm), which might facilitate bone ingrowth. However, OFGPs exhibited an increase in volumetric wear (3-10 %) compared to solid metal-backing. The objective functions were found to be more sensitive to changes in polar gradation exponent than radial gradation exponent, based on the Sobol' method. Considering the common failure mechanisms, OFGP-1, having highly porous acetabular rim and less porous dome, appears to be a better alternative to the solid metal-backing.

Clinical Outcomes and Graft Resorption After Metal-Free Bone Block Suture Tape Cerclage Fixation for Recurrent Anterior Shoulder Instability: A Computed Tomography Analysis.

BACKGROUND: Glenoid reconstruction with a bone block for anterior glenoid bone loss (GBL) has shown excellent outcomes. However, fixation techniques that require metal implants are associated with metal-related complications and bone graft resorption. HYPOTHESIS: Arthroscopic glenoid reconstruction using a tricortical iliac crest bone graft (ICBG) and metal-free suture tape cerclage fixation can safely and effectively restore the glenoid surface area in patients with recurrent anterior shoulder instability and anterior GBL. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Adult patients (≥18 years) of both sexes with recurrent anterior shoulder instability and anterior GBL ≥15% were enrolled. These patients underwent arthroscopic glenoid reconstruction with ICBGs and metal-free suture tape cerclage fixation. The effectiveness and clinical outcomes with this technique were evaluated at 24 months using functional scores. Resorption of the graft articular surface was assessed by computed tomography, with the graft surface divided into 6 square areas aligned in 2 columns. Descriptive analysis was conducted. RESULTS: A total of 23 consecutive patients met inclusion criteria (22 male, 1 female; mean age, 30.5 ± 7.9 years). The mean preoperative GBL was 19.7% ± 3.4%, and there were 15 allograft and 8 autograft ICBGs. All patients exhibited graft union at 3 months. The median follow-up was 38.5 months (interquartile range, 24-45 months). The Western Ontario Shoulder Instability Index, Rowe, Constant-Murley, and Subjective Shoulder Value scores improved from preoperatively (35.1%, 24.8, 83.1, and 30.9, respectively) to postoperatively (84.7%, 91.1, 96.0, and 90.9, respectively) (P < .001). No differences in clinical scores were observed between the graft types. One surgical wound infection was reported, and 2 patients (8.7% [95% CI, 2.4%-26.8%]) required a reoperation. The mean overall glenoid surface area increased from 80.3% ± 3.5% to 117.0% ± 8.3% immediately after surgery before subsequently reducing to 98.7% ± 6.2% and 95.0% ± 5.7% at 12 and 24 months, respectively (P < .001). The mean graft resorption rate was 18.1% ± 7.9% in the inner column and 80.3% ± 22.4% in the outer column. Additionally, 3 patients treated with an allograft (20.0% [95% CI, 7.1%-45.2%]), including the 2 with clinical failures, exhibited complete graft resorption at the last follow-up. CONCLUSION: Arthroscopic glenoid reconstruction using an ICBG and metal-free suture tape cerclage fixation was safe and effective, yielding excellent clinical outcomes. Resorption of the graft articular surface predominantly affected the nonloaded areas beyond the best-fit circle perimeter.

Evaluation and Management of Acetabular Bone Loss in Revision Total Hip Arthroplasty: A 10-year Update.

Acetabular bone loss continues to be one of the most complex and challenging scenarios facing the orthopaedic surgeon. Preoperative planning and classification systems essentially have remained the same, with the Paprosky classification still being the most commonly used. Careful radiological assessment with well-defined criteria can accurately diagnose acetabular bone loss patterns with an associated chronic pelvic discontinuity before surgery. The use of cemented reconstruction techniques has declined, and contemporary practice trends have involved the increasing use of highly porous hemispherical shells in conjunction with modular porous metal augments, which can successfully treat most acetabular revisions. Noncemented treatment options for the management of acetabular bone loss during revision include conventional porous/modular highly porous hemispherical implants, nonmodular highly porous implants with cementable acetabular liners, cup-cage reconstruction, oblong cups, and triflange reconstruction. These options can be combined with modular porous metal augments, structural allografts, impaction grafting, or reconstruction cages. Acetabular distraction is a newer technique for chronic pelvic discontinuity, which is used in conjunction with off-the-shelf revision acetabular shells and modular porous metal augments. This review is an update over the past decade, highlighting studies with mid to long-term follow-up, and presents the advantages, disadvantages, and principles associated with each of the most commonly used reconstructive techniques.

Stress shielding: short-term radiological results of the reverse shoulder arthroplasty with an anatomic proximal coated stem in proximal humeral fractures.

PURPOSE: This study aims to determine the stress shielding and other radiological outcomes of patients who underwent an uncemented reverse shoulder arthroplasty (RSA) with an anatomic proximal coated stem for complex proximal humeral fractures (PHF) with 3 or 4 parts at 2 years postoperatively. METHODS: 37 shoulders underwent an uncemented RSA for PHF from November 2015 to February 2019 and were followed up for 2 years. A radiographic assessment of stress shielding, filling ratio, stem stability (radiolucent lines/subsidence/alignment), tuberosity healing and notch was performed. RESULTS: The mean age at the time of surgery was 72 years (range, 61-85). Stress shielding was appreciated in 31 shoulders (83.8%). The most important characteristic of stress shielding is cortical resorption: Grade 3 resorption occurred in 3 shoulders (8.1%) and grade 4 in 23 (62.2%) as per the grading system defined by Inoue et al. (Inoue et al. in J Shoulder Elbow Surg 26:1984-1989, 2017). A high occurrence of bone resorption was observed in Gruen zones 2 (Lateral Stress shielding) and 7 (Medial Stress shielding). The mean distal filling ratio in patients without stress shielding was 78,48(SD 14,9), whereas in patients with stress shielding, it was slightly higher with a mean of 81,68% (SD 4,89). Tuberosity healing was found in 94.6% (35/37) of the shoulders. No patient had any radiolucent line. No notch was observed. CONCLUSION: At short-term follow-up, a high rate of tuberosity healing was achieved (94.6%) even though stress shielding was found in 83.8% (31/37) of the shoulders. Bone resorption was most frequently observed externally at zone 2 (Lateral stress shielding) and internally at zone 7 (Medial stress shielding). A higher filling ratio was associated with an increased occurrence of stress shielding. The uncemented anatomic humeral component did not result in early loosening. LEVEL OF EVIDENCE: IV; Case Series; Treatment study.

Effect of Intact Periosteum on Alveolar Ridge Contour Stability after Horizontal Guided Bone Regeneration in the Posterior Region: a Retrospective and Radiographical Cohort Study.

OBJECTIVE: To radiographically evaluate the effect of intact periosteum in guided bone regeneration (GBR) for the treatment of peri-implant ridge defects in posterior region. METHODS: Twenty-eight patients who satisfied the criteria were included in this study. Buccal dehiscence defects were regenerated using demineralised bovine bone mineral (DBBM). Subjects were divided into two groups: the control group (conventional GBR, buccal trapezoidal flap and DBBM with collagen membrane coverage, n = 14) and the test group (modified GBR, buccal pouch and DBBM with collagen membrane coverage, n = 14). CBCT images obtained immediately after and 3 to 7 months following GBR were used to assess buccal bone thickness (BBT) at a level of 0, 2, 4 and 6 mm below the implant platform. RESULTS: Immediately after surgery, BBT at 0 mm and 2 mm below the implant platform presented a significant difference between the two groups (P < 0.05) with significantly thicker buccal bone in the control group in terms of BBT-0 (3.83 ± 1.01 mm) and BBT-2 (4.88 ± 1.15 mm) than in the test group (2.33 ± 0.66 mm and 3.60 ± 1.10 mm, P = 0.000 and P = 0.008, respectively). After 3 to 7 months of healing, the BBT at all levels showed no significant difference between the two groups (P > 0.05), but more bone graft resorption (BBR) in the control group in terms of BBR-0 (2.45 ± 1.14 mm), BBR-2 (2.09 ± 0.94 mm) and BBR-0% (65.37% ± 26.62%) than the test group (BBR-0 1.07 ± 0.51 mm, P = 0.001; BBR-2, 1.22 ± 0.63 mm, P = 0.008; BBR-0% 45.70% ± 15.52%, P = 0.024). CONCLUSION: In the short term, all treatment modalities achieved similar coronal BBT and the intact periosteum had a positive effect on keeping ridge dimensions even.

Injerto en bloque en combinacióncon la técnica de split en dosfases para la rehabilitación deun caso de gran reabsorción óseadel maxilar en anchura / Block grafting in combination with the two-stage split technique for the rehabilitation of a case with severe bone resorption in width

El uso de diferentes técnicas quirúrgicas para lograr la resolución de los casos con atrofia más complejos es de vital importancia. Cada vez tenemos en la consulta casos con edentulismos de mayor duración que demandan tratamiento implantológico con prótesis fija, lo que supone un reto a la hora de planificar y llevar a cabo los tratamientos. Para ello, podemos utilizar diferentes técnicas que nos permitan ganar anchura y altura, así como implantes de distintas longitudes y diámetros que nos permitan adaptarnos a cada situación. En el presente caso clínico mostramos una rehabilitación que combina diferentes técnicas quirúrgicas para lograr el resultado buscado (AU)

The use of different surgical techniques to achieve the resolution of the most complex cases with atrophy is of vital importance. We have more and more cases with edentulism of longer duration that require implant treatment with fixed prosthesis, which is a challenge when it comes to planning and carrying out the treatments. For this, we can use different techniques that allow us to gain width and height as well as implants of different lengths and diameters that allow us to adapt to each situation. In this clinical case we show a rehabilitation that combines different surgical techniques to achieve the desired result (AU)

Actitud terapéutica frente a una reabsorción interna perforante / Therapeutic attitude against a perforating internal resorption

Atendiendo a la localización de la reabsorción radicular, ésta puede ser clasificada en externa o interna. La reabsorción interna es relativamente poco frecuente, y su etiología y patogénesis no está todavía del todo clara. Este artículo muestra la complejidad de un incisivo central superior con una reabsorción interna inflamatoria perforante. El diagnóstico definitivo lo hallamos a través del examen tridimensional, que confirmó la extensión y comunicación con la superficie externa radicular. Aunque como podremos ver a lo largo de la exposición del caso clínico, la ayuda del microscopio nos permitió abordar el caso con mayor seguridad. En todo momento pudimos eliminar el tejido inflamatorio y preparar el conducto de manera adecuada. La obturación en este tipo de casos supone un reto para el endodoncista, siendo éste, mayor cuando se realiza únicamente de manera ortógrada. Para la obturación realizamos una técnica descrita en la literatura, sellando la zona apical a la reabsorción con gutapercha adaptada mediante condensación vertical; la zona reabsortiva con material biocerámico y, por último, la zona coronal con guta-percha inyectada. Se realizó un 3D a los 26 meses para una nueva evaluación de la zona reabsortiva, y así evaluar el estado óseo alrededor de la misma. La paciente se presenta totalmente asintomática sin signos clínicos y con buena salud de los tejidos periapicales

Based on the location of the root resorption, it can be classified as external or internal. Internal resorption is relatively rare, and its etiology and pathogenesis is not yet entirely clear. This article shows the complexity of a superior central incisor with a perforating inflammatory internal resorption. The definitive diagnosis is found through the three-dimensional examination, which confirmed the extension and communication with the external root surface. Although as we can see throughout the presentation of the clinical case, the help of the microscope allowed us to address the case with greater certainty. At all times we were able to remove the inflammatory tissue and prepare the duct properly. The obturation in this type of cases supposes a challenge for the endodontist, being this one, greater when it is done only in an ortograde way. For the filling, we performed a technique described in the literature, filling the apical area with resorption with gutta-percha adapted by vertical condensation; the resorptive zone with bioceramic material and finally the coronal zone with injected gutta-percha. A 3D was performed at 26 months for a new evaluation of the resorptive zone, and thus evaluate the bone state around it. The patient presents totally asymptomatic without clinical signs and with good health of the periapical tissues

Capacitación osteogénica in vitro de células madre mesenquimales de médula ósea para su aplicación en resecciones segmentarias de hueso / Osteogenic in vitro training of bone marrow mesenquimal cells for application in segmentary bone resections

OBJETIVO: Obtener continuidad ósea en un modelo experimental de resección segmentaria en la diáfisis del fémur mediante tratamiento con células mesenquimáticas indiferenciadas comprometidas al linaje osteogénico. MATERIAL Y MÉTODO: Se obtuvieron células mesenquimáticas indiferenciadas a partir de médula ósea de ratas Wistar singénicas, se diferenciaron al linaje osteogénico y se embebieron en bloques de hidroxiapatita. Se implantaron en una resección segmentaria en la diáfisis del fémur, que se sintetizó con una placa de 1,5mm de grosor. Se calcularon distribuciones binomiales estableciéndose un grupo experimental y 3 de control, constituidos por 8 elementos cada grupo. Grupo I, relleno con aloinjerto; grupo II, con hidroxiapatita; grupo III, con hidroxiapatita embebida con células osteocomprometidas; grupo IV con células osteocomprometidas mediante cultivo tridimensional. Se realizó estadística descriptiva con distribución de frecuencias mediante la prueba de Fisher, considerándose significativo el valor de p < 0,05. RESULTADOS: El grupo I presentó buena consolidación, sin rotura de placas. El grupo II mostró tejido fibroso y rotura de todas las placas. El grupo III mostró tejido óseo, pero en todos los casos se rompieron las placas. El grupo IV mostró consolidación sin rotura de placas. CONCLUSIÓN: La terapia mediante células mesenquimáticas indiferenciadas en cultivos tridimensionales produce tejido óseo y asegura una estabilización mecánica permanente. Limitaciones: antes de la inferencia humana es necesario realizar el experimento en grupos con más elementos

OBJECTIVE: To achieve bone continuity in an experimental model of segmental resection of femur bone by applying a treatment with committed to osteogenic bone linage mesenchymal stem cells. MATERIAL AND METHOD: Bone marrow mesenchymal stem cells, obtained from syngeneic Wistar murine, were committed into osteogenic lineage and embedded within a hydroxipatite block. They were implanted in an experimentally created diaphyseal femur resection model. The diaphysis was synthetized with a 1.5mm thick plate. In order to calculate binomial distributions, we stablished one experimental and 3 control groups of 8 elements each: Group I, filling the gap with allograft; group II, filling with a hydroxyapatite block without cells; group III, filling with the hydroxyapatite block embedded with committed cells, and group IV, with the hydroxyapatite embedded with osteoinduced cells in a 3 dimensions TRAP culture. Descriptive analysis was performed by frequency distribution and Fisher statistic test. Level of statistical significance was considered at P<.05. RESULTS: Group I presented good bone consolidation and no plate breakage. Group II showed fibrous but non-bone tissue, with rupture of all plates. Group III showed bone tissue in all cases, but the plates broke in all of them, while in group IV bone consolidation was achieve without any plate rupture. CONCLUSION: Cell therapy with mesenchymal stem cells, trained in a 3 dimensions cell culture, produces bone tissue and ensures the permanence of the mechanical stabilization performed in a segmental resection model. Limitations: A study with a larger sample size is necessary before planning the human inference

Vástagos cortos versus convencionales en artroplastia total de cadera: nuestra experiencia / Short versus conventional stems in Total hipShort versus conventional stems in Total hiparthroplasty: Our experience

Objetivo: Evaluar la incidencia de complicaciones y la calidad de vida tras la cirugía en dos grupos de pacientes sometidos a artroplastia total de cadera no cementadas con vástagos corto y con vástagos estándar. Material y Métodos: Se realiza un estudio retrospectivo sobre un total de 106 artroplastias total de cadera implantadas en el Hospital Universitario de Puerto Real entre 2011 y 2015. Se comparan las siguientes variables: estancia hospitalaria, necesidad de transfusión sanguínea, complicaciones mecánicas, necesidad de revisión por cualquier causa, parámetros radiológicos (reabsorción del calcar, hundimiento, dismetría postquirúrgica, metría de cuello remanente) y dolor en cara anterior de muslo en dos grupos homogéneos de 63 vástagos convencionales anatómicos no cementados con 43 vástagos cortos de estabilización metafisaria y preservación parcial del cuello femoral ("partial collum"), implantadas por un mismo cirujano. Para el análisis estadístico se utilizó la T de Student para el análisis de variables cuantitativas y Chi cuadrado para variables cualitativas. Resultados: Los resultados muestran diferencias estadísticamente significativas (p< 0.05) en cuanto a variables estancia hospitalaria postquirúrgica, fracturas periprotésicas, dismetría, complicaciones mecánicas y metría del cuello remanente. Conclusiones: Los resultados avalan el empleo de vástagos cortos de estabilización metafisaria y preservación parcial del cuello femoral en pacientes jóvenes con adecuada calidad ósea y bien seleccionados, dadas las ventajas clínicas que suponen

Objetives: To evaluate the incidence of complications and the quality of life after surgery in two groups of patients undergoing total hip arthroplasty not cemented with a short stem and with a standard uncemented stem. Material and Methods: A retrospective study was performed in a total of 106 total hip arthroplasties implanted in the University Hospital of Puerto Real between 2011 and 2015. The following variables are compared: hospital stay, need for blood transfusion, mechanical complications, need for revision for any reason , radiological parameters (calcar resorption, subsidence, postsurgical dysmetria, remnant neck metrics) and anterior thigh pain in two homoge-nous groups of 63 conventional uncemented anatomical stems with 43 short stems of metaphyseal stabilization and partial femoral neck preservation ("Partial collum"), implanted by the same surgeon. For the statistical analysis, T Student was used for the analysis of quantitative variables and Chi-square for qualitative variables. Results: The results show statistically significant differences (p < 0.05) in terms of postsurgical hospital stay variables, periprosthetic fractures, dysmetria, mechanical complications and metrics of the remaining neck. Conclusions: The results support the use of short stems of metaphyseal stabilization and preservation of the greater trochanter in young patients with adequate bone quality given the clinical advantages they imply

Block iliac bone grafting enhances osseous healing of alveolar reconstruction in older cleft patients: A radiological and histological evaluation

Background: Older alveolar cleft patients (>12 years old) often have wide bone defect as well as teeth loss, resulting in poor osseous healing with conventional alveolar bone grafting (ABG). In this study, we investigated a surgical technique of block iliac bone grafting for the alveolar cleft reconstruction and evaluated the clinical and radiological outcomes of these cleft patients. Material and Methods: Fifteen patients were included in this study. All cases received preoperative cone bean computed tomography (CBCT) scans for the alveolar cleft evaluation. Osseous outcomes of block iliac bone grafting were assessed at 1 week, 3- and 6-month postoperatively. Volume changes and bone resorption rates were calculated using the measurement modules of Simplant software. Bone samples from one patient undergoing dental implantation were assessed by micro-CT and histological examination. The morbidities of donor-site were analyzed by clinical examination and questionnaire survey. Results: The average age of the case series was 18.53±2.50 years. The intraoral incision of thirteen cases healed well. However, two cases had oronasal fistula and graft exposure at 1-week postoperatively. The results of follow-up CBCT scans showed significant resistance to radiation on both sides of the bone graft, suggesting a good osseous healing and new bone formation. The mean residual bone volume was 1.68±0.26 cm3 , 1.29±0.23 cm3 and 1.15±0.23 cm3 at 1-week, 3- and 6-month postoperatively. Correspondingly, the mean bone resorption rates in 3- and 6-month postoperative were 21.78±6.88% and 30.66±8.97%, respectively. From micro-CT and HE examinations, the block bone samples exhibited a cancellous structure in which mature bone trabecula and functional blood vessels appeared. The average scores of donor-site morbidities were drastically decreased at 3- and 6-month postoperatively compared with those at 1-week postoperatively. Conclusions: Our results demonstrated that block iliac bone grafting could achieve satisfying osseous outcomes in older alveolar cleft patients, and this technique provided favorable bony condition for further treatments, especially dental implantation (AU)

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Enxerto interposicional na região posterior da mandíbula ­ relato de caso / Interpositional bone graft in the posterior mandibular region ­ a case report

A instalação de implantes osseointegráveis na região posterior da mandíbula ainda pode ser considerada um grande desafio, principalmente em casos que envolvam reabsorção óssea vertical avançada. A técnica de aumento ósseo vertical por meio de enxerto interposto é uma alternativa interessante para a reconstrução desses defeitos. Por meio desta técnica, é possível um ganho vertical variando de 6 a 12 mm, possibilitando a instalação dos implantes com segurança. Este relato tem como objetivo demonstrar o passo a passo para a realização da técnica de aumento vertical por meio de enxerto de bloco ósseo interposto, fixado por meio de placa e parafuso de titânio (AU).

The installation of dental in implants the posterior mandible is still considered a major challenge, especially in cases with advanced vertical bone resorption. The vertical bone augmentation technique by means of interpositional bone grafts is an interesting alternative for the reconstruction of these defects. Through this technique, a vertical gain ranging from 6 to 12 mm is possible, allowing the placement of the implant safely. This report aims to demonstrate the step-by-step towards vertical bone augmentation technique through interposed bone block graft fixed by miniplate osteosynthesis (AU).

Reabsorção óssea associada ao implante de silicone em mentoplastia: relato de caso clínico / Bone reabsorption associated with silicone implants in mentoplasty: a clinical case report

Durante muitos anos, os implantes de silicone foram utilizados em cirurgias reconstrutivas e estéticas, principalmente em casos em que o perfil facial do paciente apresenta deficiência no terço inferior da face. Este material tem provado ser bem sucedido na maioria dos aspectos, contudo, algumas complicações já foram bem relatadas na literatura, como é o caso das reabsorções ósseas na região de mento mandibular. No presente artigo os autores apresentam dois casos clínicos de reabsorção óssea da cortical anterior do mento, associada ao implante de silicone e discutem a etiologia, as complicações e o plano de tratamento.

For many years, silicone implants were used in reconstructive and esthetic surgeries, especially in cases in which the facial profile of patients presented deficiencies in the inferior third of the face. This material proved to be successful in most aspects. However, several complications were well reported in the literature, as the case of bone reabsorption in the region of the mandibular chin. In this article, the authors present two clinical cases of bone reabsorption from the anterior cortex of the chin associated with silicone implants and discuss the etiology, complications, and treatment plan.

Implante dentário associado à regeneração óssea guiada (ROG) no tratamento do edentulismo unitário em área estética ­ relato de caso / Single-tooth implant associated with guided bone regeneration (GBR) in esthetic zone ­ case report

A inserção de implantes osseointegráveis simultaneamente com a regeneração óssea guiada (ROG) é uma alternativa de tratamento que possibilita a reconstrução do defeito ósseo causado pela reabsorção alveolar. Esta técnica permite a instalação do implante em uma posição favorável na mesma intervenção cirúrgica e ter restaurações protéticas com melhores características estéticas e funcionais. Associado a isso, a possibilidade de utilização de biomateriais aloplásticos, como a hidroxiapatita, na técnica de ROG, diminui a morbidade do procedimento cirúrgico, promovendo maior conforto ao paciente. O objetivo deste trabalho é apresentar um relato de caso de reabilitação da região do incisivo central superior com a instalação de um implante osseointegrável associado à ROG utilizando hidroxiapatita sintética e membrana de colágeno reabsorvível. Através da avaliação tomográfica, pode-se observar um ganho de volume ósseo vestibular na região tratada e, ao final do tratamento, foram obtidos resultados estéticos e funcionais satisfatórios corroborando com a literatura (AU).

The use of dental implants and guided bone regeneration (GBR) simultaneously is an alternative treatment that allows reconstruction of bone defects caused by alveolar resorption and implant installation in a favorable position in a single surgical intervention, allowing the realization of prosthetic restorations with better aesthetic and functional characteristics. Associated with this, the possibility of using alloplastic biomaterials such as hydroxyapatite, in GBR technique, decreases the morbidity of surgical procedure, providing greater comfort to the patient. The objective of this study is to present a clinical case which an osseointegrated implant associated with GBR using synthetic hydroxyapatite and resorbable collagen membrane for prosthetic rehabilitation of the upper left central incisor was installed. Through tomographic evaluation, we may observe a buccal bone volume gain in the treated área and, at the end of treatment, satisfactory aesthetic and functional results showed predictability and safety of the technique corroborating the literature (AU).

Maxillary crestal bone loss around bredent sky blue implants: one year study

Objective: To analyze the amount of crestal bone loss of the mandible around implants of different diameters one year after implantation. Material and Methods: The study included a total of 42 male and female patients. A total of 73 implants were evaluated (12 implants of diameter 3.5 x 10 mm and 61 implants of diameter 4.0 x 8 mm). Dental panoramic radiographs were made before surgery, immediately after surgery and one year later. The measurements were performed using Kodak dental software 6.11.7.0 after implantation and one year later. The data were analyzed using the IBM SPSS v.17 software package (descriptive statistics, paired samples t-test). Results: Among male patients, 43.5% were smokers, while among females, 57.9% were nonsmokers. Crestal bone resorption was greater mesially than distally, although differences were not statistically significant (p<0.05). Conclusion: All implants showed successful tissue integration. Crestal bone resorption was greater mesially than distally, although differences were not statistically significant...

Implantes zigomáticos como alternativa para reabilitaçãode maxilas atróficas / Zygomatic implants as an alternative for rehabilitation of atrophic maxilla

Existem casos em que o processo reabsortivoda maxila atinge níveis tão severos que nãohá suporte ósseo adequado para instalação deimplantes. Assim, os implantes zigomáticos surgiramcomo alternativa complementar e queapresenta elevados índices de sucesso descritosna literatura. Seu princípio se baseia no fato deque o osso zigomático não sofre o processo dereabsorção a que estão sujeitos os ossos maxilaresapós a perda dos elementos dentais. Nesteartigo relatamos um caso clínico de uma pacienteque apresentava uma reabsorção severada maxila e foi tratada por meio de implanteszigomáticos e implantes convencionais, recebendouma prótese provisória sete horas apóso procedimento cirúrgico. Esta técnica, além depossibilitar a reabilitação dos pacientes edêntulos,permite a instalação de prótese em umprotocolo de carga imediata caso os implantesatinjam um bom travamento inicial.

There are cases where the resorptive processof the maxilla reaches levels so severe thatthere is adequate bone support for implantplacement. So the zygomatic implants haveemerged as an alternative complementary inwith high success rates in the literature. Itsprinciple is based on the fact that the zygomaticbone does not undergo the process ofresorption they are subject to the jaws followingthe loss of dental elements. In this reporta case of a patient who had a severe resorptionof the jaw and was treated by means of zygomaticimplants and conventional implants andreceived a temporary prosthesis seven hoursafter surgery. This technique also enable therehabilitation of edentulous patients, allowsthe installation of prosthesis in a protocol ofimmediate load implant case to achieve a goodinitial crash.

Aumento del reborde alveolar residual mediante técnica de rollo / Increase of residual alveolar ridge using roll technique

La pérdida dentaria, asociada a factores sistémicos, patológicos y traumáticos, promueve el proceso de reabsorción ósea de los rebordes residuales y genera problemas funcionales, como la falta de estabilidad y retención de las prótesis dentarias removibles, y disturbios estéticos y psicológicos. Estos defectos varían en dependencia de la cantidad de pérdida ósea y de tejidos blandos que hayan alcanzado. En la actualidad son descritas diversas técnicas que permiten corregir estos defectos. Una de ellas es la técnica del rollo, la cual demuestra muy buenos resultados al aumentar el tamaño del reborde alveolar y disminuir los defectos estéticos que causa sobre todo en el sector anterior. El objetivo del presente artículo es describir el caso clínico de un paciente con pérdida ósea en el sector anterior, tipo III según Seibert, rehabilitado con prótesis parcial fija y sometido a un procedimiento quirúrgico con la técnica del rollo. Se alcanzaron los objetivos planteados y proporciona una mejoría estética así como una mejora en su calidad de vida. Se demostró que con esta técnica se obtienen resultados predecibles que devuelven la estética en zonas de alta exigencia por parte de los pacientes(AU)

Tooth loss associated with systemic factors, pathological and traumatic conditions, promotes the bone resorption of residual ridges, this, creates functional problems such as lack of stability and retention of removable dentures as well as aesthetic and psychological disturbances. These defects vary depending on the amount of bone loss and soft tissue they reach. At present there are described various techniques that can correct these defects. One of these is the roll technique which shows very good results by increasing the size of the alveolar ridge and decrease aesthetic defects in the anterior area of the maxilla. The aim of this article is to describe a case of a patient with Seibert bone loss type III, rehabilitated with fixed partial denture after undergoing a surgical procedure with the roll technique achieving the stated objectives and providing aesthetic improvement to the patient and an improvement in their quality of life. It is shown that the technique can be achieved with predictable results that return aesthetics in areas of high demand from patients(AU)

Autogenus calvarium bone grafting as a treatment for severe bone resorptionin the upper maxilla: A case report

Atrophic maxilla rehabilitation has been the subject of several studies for decades; despite this, there are still manydifferent therapeutic choices for the best way to treat maxillary resorption in order to enable implant placementand integration. These possibilities include the optimal use of remaining bone structures, such as the pterygoidprocesses or zygomatic arch, which involves using zygomaticus and pterygoid implants in combination with standardimplants placed in the residual bone; alternatively, regenerative techniques, alveolar bone expansion/distractionor bone grafting techniques may be used. Severe maxillary atrophy has a multifactorial aetiology; the mostimportant factors being long evolution edentulism, hyperpneumatization of the maxillary sinus, post-traumaticdeficit, bone loss after surgery (tumours, cysts) and periodontal problems or infection. In this report, we present aclinical case of onlay block reconstruction in an atrophic maxilla with harvested cranial calvarium bone grafts forsuccessful future implant-supported oral rehabilitation (AU)

Tratamiento de pérdidas óseas, pseudoartrosis, artrodesis y tumores óseos benignos con un xenoimplante mexicano (estudio clínico) / Bone loss treatment, pseudoarthrosis, arthrodesis and benign tumors using xenoimplant: clinical study

Objetivo: Se trataron pérdidas óseas, artrodesis, pseudoartrosis, tumores benignos y defectos óseos con un xenoimplante. Material y métodos: Se evaluó la eficacia del material mediante un estudio observacional y longitudinal en el Hospital Regional “General Ignacio Zaragoza” del ISSSTE. Resultados: Fueron considerados 52 pacientes, 28 masculinos y 24 femeninos, de los cuales a 28 se les practicó artrodesis, 16 fueron tratados por pseudoartrosis, tres presentaron tumores óseos benignos y cinco defectos óseos, a los cuales se les colocó el xenoimplante en el sitio y forma adecuada según el problema por tratar. El promedio de edad de los pacientes fue de 47.7 años, con un rango de nueve a 84 años. Se presentó consolidación ósea entre los tres y ocho meses después de la cirugía; el xenoimplante se integró totalmente en un periodo de tres a 18 meses dependiendo del tamaño de la patología y la región donde fue colocado. La consolidación ósea fue valorada radiográficamente de acuerdo con la clasificación de Montoya. Ningún paciente presentó signos clínicos de rechazo. Conclusiones: En México se han empleado xenoimplantes óseos de origen extranjero debido a la gran dependencia tecnológica del país. Por primera vez se utiliza un xenoimplante producido en el país y cuya patente es de la Universidad Nacional Autónoma de México. El xenoimplante Nukbone® fue biocompatible y resultó adecuado para tratar patologías donde se requiere aporte óseo.

BACKGROUND: Bone loss as a result of arthrodesis, pseudarthrosis, benign tumors and bone defects was treated using a xenoimplant (Nukbone). METHODS: The effectiveness of the material was evaluated through a longitudinal and observational study at the Hospital Regional "General Ignacio Zaragoza" (HRGIZ) ISSSTE. The Mexican xenoimplant is a patent of the National Autonomous University of Mexico (UNAM). RESULTS: Fifty two patients were considered regardless of age or gender. Of these patients, 28 were male and 24 female. Average age of the patients was 47.7 years (9-84 years). Twenty eight patients had arthrodesis, 16 were treated with pseudarthrosis, three patients had benign tumors and five patients presented bone defects, which were implanted with Nukbone at the site and was the correct treatment for the problem. The xenoimplant is fully integrated during a period of 3-18 months, depending on the size of the pathology and the region where it was placed. Fracture healing was evaluated radiographically according to the classification of Montoya. No patient had clinical signs of rejection. CONCLUSIONS: In Mexico, bony xenoimplants (osseous) have been used, all of foreign origin due to the high degree of technological dependence in this country. In this study we describe the use, for the first time, of a Mexican xenoimplant with a patent from the Universidad Nacional Autónoma de México (UNAM). The Mexican xenoimplant is biocompatible and can be adapted to treat pathologies where bony (osseous) material is needed.

Rehabilitation of atrophic maxilla: A review of 101 zygomatic implants

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Introduction: Zygomatic implants are a good rehabilitation alternative for upper maxilla with severe bone reabsorption. These implants reduce the need for onlay-type bone grafting in the posterior sectors and for maxillary sinus lift procedures - limiting the use of bone grafts to the anterior zone of the upper jaw in those cases where grafting is considered necessary.Objective: To evaluate the survival of 101 zygomatic implants placed in upper maxilla presenting important bone reabsorption, with a follow-up of 1-72 months.Patients and methods: A retrospective study was made of 101 Zygoma® implants (Nobel Biocare, Göteborg, Sweden)placed in 54 patients with totally edentulous and atrophic upper maxilla, in the period between 1998-2004. There were 35 women and 19 men, subjected to rehabilitation in the form of fixed prostheses and overdentures using 1-2 zygomatic implants and 2-7 implants in the anterior maxillary zone. The principal study variables were smoking, a history of sinusitis, the degree of bone reabsorption, and peri-implant bone loss, among others.Results: The descriptive analysis of the 101 zygomatic implants placed in 54 patients with a mean age of 56 years (range 38-75) yielded a percentage survival of 96.04%, with four failed implants that were removed (two before and two after prosthetic loading). Nine patients were smokers, and none of the 54 subjects reported a history of sinus disorders.Discussion and conclusions: Zygomatic implants are designed for use in compromised upper maxilla. They allow the clinician to shorten the treatment time, affording an interesting alternative for fixed prosthetic rehabilitation. This study confirms that zygomatic bone offers predictable anchorage and acceptable support function for prostheses inatrophic jaws. However, these implants are not without complications. Longer-term evaluations are needed of zygomatic implant survival in order to establish a correct clinical prognosis (AU)

¿Qué indicaciones tienen y qué resultados nos ofrecen los Implantes Cigomáticos? / What are then indications of the zygomatic fixture and what results do offer us?

En muchos casos el tratamiento con implantes convencionales no puede realizarse en el maxilar edéntulo debido a la extensa reabsorción ósea ya la presencia de senos maxilares neumatizados, dejando cantidades inadecuadas de tejido óseo para el anclaje de los implantes. La opción terapéutica para estos pacientes ha consistido en realizar algún tipo de procedimiento de aumento óseo para incrementar el volumen de hueso para soportar las cargas. Tradicionalmente el maxilar atrófico se ha tratado con grandes injertos óseos de la cresta ilíaca, un procedimiento que requiere anestesia general, y/o técnicas como la elevación del suelo sin usal. Una alternativa que aquí planteamos es la utilización de implantes cigomáticos colocados en el arco cigomático en combinación con implantes convencionales colocados en el hueso residual. La comparativa sencillez de la técnica, la falta de morbilidad dela zona dadora y un periodo de curación más corto y confortable para el paciente, sugieren que el implantes cigomático es una alternativa más simple a las otras técnicas (AU)

In many cases conventional implant treatment cannot be performed in the edentulous maxilla because of extensive bone resorption and the presence of extensive maxillary sinuses, leading to inadequate amounts of bone tissue for anchorage of the implants. The treatment option for these patients has often been some type of bone augmentation procedure in order to increase the volume of load-bearing bone. Traditionally the atrophic maxilla has been treated with large bone grafts from the iliac crest, a procedure that requires general anesthesia, and/or techniques such as sinus floor augmentation. An alternative is the use of the zygomatic fixture placed in the zygomatic arch in combination with regular implants placed in residual bone. The comparative simplicity of the technique, the lack of morbidity of a graft zone and a shorter and more comfortable healing period suggest that the zygomatic fixtures are a simpler alternative to other techniques (AU)