Delayed Bleeding of Sphenopalatine Artery as a Complication in Le Fort I Osteotomy.

ABSTRACT: Rates of severe complications in orthognathic surgery are low, but when they occur they can be fatal. This article reports a case of laceration of the junction of the posterior lateral nasal artery and the sphenopalatine artery, resulting in severe delayed bleeding. Patient undergoes a multiple segment Le Fort I osteotomy with no intraoperative or immediate postoperative complications. On the fourth postoperative day, he presents with epistaxis and intractable postnasal discharge, is admitted to emergency with signs of shock, and bleeding is detected endoscopically originating from the right sphenopalatine artery, which is treated with diathermocoagulation. The advantage of endoscopy in difficult areas is that bleeding complications can be solved with low morbidity.

Patient Specific Implants to Solve Structural Facial Asymmetry After Orthognathic Surgery.

ABSTRACT: Facial asymmetry is a challenge for surgeons. Some surgical strategies could be used involved soft or hard tissue of the face. The aim of this report is to show the use of patient specific implants (PSI) in a puzzle strategy based on computer aided design/computer aided manufacturer to solve a complex structural facial asymmetry after orthognathic surgery. Twenty-five-year-old male patient complain for facial asymmetry after orthognathic surgery; main deformity was related to the shape of mandibular bone in the ramus, angle, and body. After mirror image, was chose an augmentation in the right side using 2-pieces patient specific implants and the bone reduction in the vertical high of the mandibular body in the left side. Surgical technique was realized by intra oral approach installing the ramus segment at first approach and the body segment as second to obtain stability in the fitting implant-bone-implant; the left side was treated using a guide for osteotomy; after 1-year follow-up no infection or complication was observed and facial symmetry was obtained. It is possible to conclude that the puzzle technique using polyetheretherketone can be applied to obtain predictable results in a simple strategy to solve a complex problem.

Mandibular Angle Contouring Using Porous Polyethylene Stock or PEEK-based Patient Specific Implants. A Critical Analysis.

ABSTRACT: Contour augmentation and mandibular angle modification surgery is becoming increasingly. The aim of this research is to compare technique and outcomes in augmentations done with standard implants or PEEK-based patient specific implants (PSI) in mandibular angle. Data from surgical planning, operative and post-operative of 6 months follow-up were revised for 21 patients who were submitted to facial surgery using a stock implant obtained from companies currently on the market or 3D implants created with CAD/CAM technology using PEEK 3D printing. Surgical time, intra-operative and post-operative complications were compared, analyzing the advantages and disadvantage of each technique. Statistical analyses using t-test and chi-squared were performed considering P value< 0.05 for statistical differences. Twelve patients were operated on with stock implants and nine patients with PSI. The surgical time was 15 minutes less for the 3D implant surgeries (P = 0.021) and intraoperatively only the stock implants needed modifications with wear and adaptation methods; post-operative infections were observed in both groups with no significant differences (P > 0.05). The 3D implants had greater levels of facial symmetry than the stock implants, although they did not present significant differences.Considering the limitations of this study, mandibular angle implants with a PEEK-based 3D CAD/CAM are efficient, stable and have a low complication rate; the CAD/CAM strategy is useful in facial surgery and can be integrated as a standard for surgical planning in facial makeover surgery.

Alveolar Cleft Reconstruction Using Morphogenetic Protein (rhBMP-2): A Systematic Review and Meta-Analysis.

OBJECTIVE: This study aimed to review the existing evidence regarding reconstruction of the alveolar cleft using recombinant human bone morphogenetic protein-2 (rhBMP-2) in terms of bone volume and bone height. DESIGN: Systematic review and meta-analysis. PATIENTS­PARTICIPANTS: A systematic search was done. Randomized and nonrandomized clinical trials, where rhBMP-2 was used in the reconstruction of human alveolar cleft were included. INTERVENTIONS: Reconstruction of alveolar cleft with rhBMP-2. MAIN OUTCOME MEASURES: Average bone volume formation and average bone height formation in the alveolar cleft. Mean difference was calculated and pooled by meta-analysis. RESULTS: Of 709 identified articles, 5 studies met the inclusion criteria. The average bone volume formation was higher in the rhBMP-2 group than in the control group (61.11% vs 59.12%). The average bone height formation was higher in the control group compared to the rhBMP-2 group (75.4% vs 61.5%). The risk of bias in the selected articles was high. The meta-analysis showed that rhBMP-2 treatment may benefit bone formation compared to iliac crest graft (low certainty evidence; mean difference: -208.76; 95% confidence interval: -253.59 to -163.93; -I2 = 0%). CONCLUSIONS: The results obtained in primary articles are promising but have a high risk of bias and have low quality of evidence; therefore, it is necessary to conduct controlled clinical trials with a greater number of patients to recommend the use of rhBMP-2 in the treatment of the alveolar cleft. PROSPERO registration number: CRD42018077741.

Temporomandibular Joint Ankylosis: Algorithm of Treatment.

: Temporomandibular joint ankylosis, according to age of onset, causes severe functional and morphological disorders, as well as stunted craniofacial growth and development.The primary goal of treatment is to resolve the functional and morphological disorders. METHOD: Pre- and posttreatment clinical and cephalometric registries were conducted in 15 patients with temporomandibular joint ankylosis over a 10-year period (2002-2012). All the patients underwent complete removal of the ankylotic block, gap arthroplasty, and ipsilateral coronoidectomy. Distraction osteogenesis was performed on 12 patients. RESULTS: Fifteen patients, 8 female and 7 male, ranging from 3 to 30 years of age, were included in this study. The posttreatment follow-up period ranged from 3 to 13 years.The mean preoperative maximum mouth opening was 3 ± 1.7 mm, and the mean postoperative maximum mouth opening was 36 ± 6.5 mm. The labial inclination with respect to the true horizontal decreased considerably (6.2° ± 2.3° preoperative to 1° ± 1.6° postoperative). A correction of the mandibular deviation was measured at the symphysis with respect to the facial midline (8° ± 2° preoperative to 2° postoperative). Finally, the height ratio of both mandibular rami (the healthy side and the affected side) decreased considerably (1.27 ± 0.05 preoperative to 1.07 ± 0.06 postoperative).Reankylosis only occurred in 2 patients, who were then successfully treated by means of gap arthroplasty. CONCLUSIONS: The therapeutic algorithm proposed in the present work provides favorable functional and morphological results. Early and aggressive functional physiotherapy is essential to minimize the risk of reankylosis.

Comparison of rhBMP-2 in Combination with Different Biomaterials for Regeneration in Rat Calvaria Critical-Size Defects.

Regeneration of critical bone defects requires the use of biomaterials. The incorporation of osteoinductive agents, such as bone morphogenetic proteins (BMPs), improves bone formation. This study aimed to compare the efficacy of rhBMP-2 in combination with different materials for bone regeneration in critical-sized rat calvarial defects. This was an experimental animal study using 30 rats. In each rat, two 5-mm critical-size defects were made in the calvaria (60 bone defects in total) using a trephine. All rats were randomized to one of the six groups: control (C), autograft + rhBMP-2 (A), absorbable collagen sponge + rhBMP-2 (ACS), ß-tricalcium phosphate + rhBMP-2 (B-TCP), bovine xenograft + rhBMP-2 (B), and hydroxyapatite + rhBMP-2 (HA). The outcome was assessed after 4 and 8 weeks using histological description and the histological bone healing scale. Statistical analysis was performed using the Kruskal-Wallis and Mann-Whitney U tests, with a p-value set at 0.05. The average bone healing scores per group were as follows: C group, 12.5; A group, 26.5; ACS group, 18.8; B-TCP group, 26.2; HA group, 20.9; and B group, 20.9. The C group showed a significant difference between weeks 4 and 8 (p = 0.032). Among the 4-week groups, the C group showed a significant difference compared to A (p = 0.001), ACS (p = 0.017), and B-TCP (p = 0.005) groups. The 8-week experimental group did not show any significant differences between the groups. The 5-mm critical size defect in rat calvaria requires the use of bone biomaterials to heal at 4 and 8 weeks. rhBMP-2, as applied in this study, showed no difference in new bone formation when combined with bovine, B-TCP, or HA biomaterials.

Patient-specific Implant for Temporomandibular Joint Replacement in Juvenile Arthritis and Facial Asymmetry.

The aim of this report is to present a patient with juvenile arthritis, condylar resorption, and residual facial asymmetry treated with orthognathic surgery and unilateral joint replacement with a full three-dimensional computer-aided design and computer-aided manufacture (CAD-CAM) temporomandibular joint (TMJ) prosthesis, including an increase in the left ramus and mandibular angle to achieve facial symmetry. The patient, a 30-year-old male, came to our department for orthosurgical treatment. The patient had been receiving treatment for juvenile arthritis for 15 years; at facial level, he had a chin deviation of 12 mm from the facial midline, maxillary retrusion, and Angle Class III. The computed tomography revealed a reduced height of the left condyle and a significant difference in the morphology of the mandibular ramus and angle. Using CAD-CAM technology and additive manufacturing, a TMJ prosthesis was produced, through the use of the mirror image, orthognathic surgery was realized using the right side as "esthetic side" with suitable shape and angulation. The prosthesis was created, and this was taken to the surgery. The surgery was performed without problems, a mouth opening of 35 mm and absence of pain were noted after 12 months of follow-up. The surgery remained stable, and facial symmetry was restored. In conclusion, it is viable to develop a TMJ prosthesis by CAD-CAM that includes esthetic modifications to the face; prospective and clinical studies must be conducted to confirm protocols. Level of Evidence: V.

Late correction of orbital deformities using customized 3D implant / Corrección tardía de deformidades de órbita usando implantes personalizados 3D

SUMMARY: Late orbital reconstruction is a complex and challenge for surgeons. The aim of this article is to present complex orbital reconstruction using patient specific implant (PSI) strategy and polyetheretherketone (PEEK). A literature review and a cases series of sequelae after complex orbital trauma are presented; cases with great middle third deformities showing defect in the maxilla, nasal area, body of the zygoma and zygomatic arch were included; in both cases the sequelae was for more than 10 years. Virtual planning and PEEK implants were manufacture using a puzzle (two or three parts) by 3D print or injection. Patients were treated and their surgeries carried out without complications, using a minimal surgical approach. No infections were observed, and after 12 months follow-up they were stable showing normal function. PSI based-PEEK for orbital reconstruction are safe, efficient, effective and to obtain orbital morphology with low complications.

RESUMEN: La reconstrucción tardía de la órbita es un desafío complejo para cirujanos. El objetivo de este artículo fue presentar la reconstrucción orbitaria compleja utilizando implante paciente específico (PSI) y polietereterketona (PEEK). Son presentados una revisión de literatura y una serie de casos con secuelas posteriores a un trauma orbitario complejo; además, son presentados casos con gran deformidad del tercio medio del rostro mostrando defectos en maxila, área nasal, cuerpo del hueso cigomático y arco cigomático; ambos casos de secuela fueron por más de 10 años. Planificación virtual e implantes en PEEK fueron creados usando una estrategia de puzzle (dos o tres partes) por inyección o impresión 3D. Los pacientes fueron tratados y sus cirugías realizadas sin complicaciones usando accesos quirúrgicos reducidos. No se observaron infecciones y después de 12 meses de seguimiento permanecieron estables mostrando función normal. Los PSI para reconstrucción orbitaria son seguros, eficientes, efectivos y recuperan morfología de órbita con bajas complicaciones.

Indications of Free Grafts in Mandibular Reconstruction, after Removing Benign Tumors: Treatment Algorithm.

BACKGROUND: Mandibular reconstruction has been the subject of much debate and research in the fields of maxillofacial surgery and head and neck surgery. MATERIALS AND METHODS: A retrospective observational study was undertaken with 14 patients diagnosed with benign tumorous pathologies and who underwent immediate mandibular resection and reconstruction at the Hospital del Salvador Maxillofacial Surgery Unit and Dr. Rodrigo Fariña's private clinic between the years 2002 and 2012. We propose a treatment algorithm, which is previous teeth extractions in area that will be removed. RESULTS: Fourteen patients underwent surgery, and a total of 40 dental implants were installed in 6 men and 8 women, the mean age of 33.5 (age range, 14-58 y). Reconstruction with iliac crest bone graft, and rehabilitation following this protocol (average of reconstruction was 8.7 cm), was successful with no complications at all in 12 patients. One patient had a minor complication, and the graft was partially reabsorbed because of communication of the graft with the oral cavity. This complication did not impede rehabilitation with dental implants. Another patient suffered the total loss of the graft due to infection because of dehiscence of oral mucosa and great communication with the mouth. Another iliac crest free graft reconstruction was undertaken 6 months later. CONCLUSIONS: The scientific evidence suggests that mandibular reconstruction using free grafts following the removal of benign tumors is a biologically sustainable alternative. The critical factor to improve the prognosis of free grafts reconstruction in benign tumors is to have good quality soft tissue and avoid communication with the oral cavity. For this, it is vital to do dental extractions before removing the tumor.

Orthognathic surgery in craniofacial microsomia: treatment algorithm.

Craniofacial microsomia is a broad term that covers a variety of craniofacial malformation conditions that are caused by alterations in the derivatives of the first and second pharyngeal arches. In general terms, diverse therapeutic alternatives are proposed according to the growth stage and the severity of the alteration. When craniofacial growth has concluded, conventional orthognathic surgery (Le Fort I osteotomy, bilateral sagittal split osteotomy, and genioplasty) provides good alternatives for MI and MIIA type cases. Reconstruction of the mandibular ramus and temporomandibular joint before orthognathic surgery is the indicated treatment for cases MIIB and MIII. The goal of this article is to establish a surgical treatment algorithm for orthognathic surgery on patients with craniofacial microsomia, analyzing the points that allow the ideal treatment for each patient to be chosen.

Influencia de rhBMP-2 en la reparación ósea de defectos críticos con diferentes biomateriales / Influence of rhBMP-2 on bone repair of critical size defects with different biomaterials

La regeneración de defectos óseos críticos requiere la utilización de biomateriales óseos. Así, se han utilizados agentes osteogénicos como la proteína morfogenética (rhBMP-2). El objetivo fue describir la formación ósea de defectos óseos críticos en calota de ratas utilizando rhBMP-2 con distintos biomateriales. Se realizaron dos defectos óseos críticos de 5 mm en 15 calotas de ratas machos adultas divididos en grupo control (sin tratamiento) (C); autoinjerto + rhBMP-2 (A); fosfato tricálcico + rhBMP-2 (BTCP); xenoinjerto de bovino + rhBMP-2 (B) y hidroxihapatita + rhBMP-2 (HA). A las ocho semanas post tratamiento, se realizó la eutanasia y posterior análisis histológico de los defectos. El grupo C no presentó formación de tejido óseo en el defecto. En el resto de los grupos, se formó abundante tejido óseo en los márgenes, por lo tanto, el defecto presentó menor tamaño. El grupo HA presentó formación ósea trabecular con amplios espacios medulares y abundante tejido adiposo. El grupo B-TCP también presentó formación ósea trabecular y la mayoría de las muestras presentaron puente óseo en el defecto. El grupo B presentó partículas de material injertado rodeado por trabéculas óseas y tejido conectivo. En el grupo A, todas las muestras presentaban puente óseo formado por bloques de autoinjerto rodeado por tejido conectivo y óseo. Es posible concluir que los defectos óseos de 5 mm en calota de rata son defectos críticos que requieren utilizar biomateriales para la reparación del defecto. El grupo B-TCP presentó características histológicas más próximas a la regeneración ósea lograda con el Grupo A.

The regeneration of bone critical size defects requires the use of bone biomaterials. Therefore, an osteogenic agent such as bone morphogenetic protein (rhBMP-2) has been used. The objective was to describe the bone formation of bone critical size defects in the rat calvaria using rhBMP-2 with different biomaterials. Two critical bone defects of 5 mm were made in 15 calvaria of adult male rats divided into a control group (without treatment) (C); autograft + rhBMP-2 (A); tricalcium phosphate + rhBMP-2 (B-TCP); bovine xenograft + rhBMP-2 (B) and hydroxyhapatite + rhBMP-2 (HA). At eight weeks post treatment, euthanasia and subsequent histological analysis of the defects were performed. Group C did not show bone tissue formation in the defect. In the rest of the groups, abundant bone tissue formed in the margins, therefore, the defect was smaller. The HA group presented trabecular bone formation with large medullary spaces and abundant adipose tissue. The B-TCP group also presented trabecular bone formation and most of the samples formed a bone bridge across the defect. Group B presented grafted material particles surrounded by bone trabeculae and connective tissue. In group A, all samples presented a bone bridge formed by autograft blocks surrounded by connective and bone tissue. It is possible to conclude that 5 mm bone defects in rat calvaria are critical size defects that require the use of biomaterials for defect repair. The B-TCP group presented histological characteristics similar to the bone regeneration achieved with Group A.

Osteonecrosis of the jaw in patient with denosumab therapy.

Osteonecrosis (ON) of the jaw has previously been linked to the use of biphosphonates; however, new drugs, also shown similar conditions. This article presents a female patient with mandibular ON related to the use of denosumab. The 55-year-old presented with bone exposure with 8 months of evolution after a dental extraction. The patient began subcutaneous injections of 60 mg denosumab four months prior to the extraction and the lesion remained after the procedure. The patient, with 14 months of follow-up, show mandible ON with no favorable evolution. The clinical condition is presented and the literature of ON associated with denosumab is discussed.

Characterization of bone substitute beta946; -TCP block for maxillofacial reconstruction / Caracterización del bloque beta946; -TCP de sustitución ósea para la reconstrucción maxilofacial

SUMMARY: The aim of this study was to characterize a commercial beta tricalcium phosphate (β-TCP) block allograft for use in maxillofacial reconstruction, evaluating its homogeneity, porosity and mineralization. Two commercial 5 x 5 x10 mm chronOS Vivify β-TCP blocks were used, which were evaluated by a STEM SU-3500 variable pressure scanning electron microscope (SEM-STEM) (Hitachi, Japan). For the semi-quantitative microanalysis of elements, the QUANTAX 100 energy dispersive x-ray spectrometer detector (EDX) (Bruker, Germany) was used. The homogeneity of the structural morphology, macropore and micropore size and component homogeneity were evaluated. The microscopic analysis showed micropores of 164.92 mm (± 35.032 mm) in diameter in the outer area and micropores in the inner area of 54.44 mm (± 17.676 mm). The formation of porosities and irregularities present in the block was heterogeneous between the outer and inner surfaces. The mineral content of the blocks presented homogeneity with the presence of carbon (2.02 %), oxygen (44.33 %), phosphate (16.62 %) and calcium (37.87 %). The β-TCP block can be used in bone reconstruction but the presence of reduced macropore and micropore sizes could limit efficiency in the substitution and bone regeneration phase.

RESUMEN: El objetivo de este estudio fue caracterizar un aloinjerto de bloqueo de fosfato tricálcico (β-TCP) comercial para su uso en la reconstrucción maxilofacial, evaluando su homogeneidad, porosidad y mineralización. Se utilizaron dos bloques comerciales de 5 x 5 x 10 mm de vivify β-TCP de chronOS, que se evaluaron mediante un microscopio electrónico de barrido de presión variable STEM SU-3500 (SEM-STEM) (Hitachi, Japón). Para el microanálisis de elementos semicuantitativo, se utilizó el detector de espectrómetro de rayos X de dispersión de energía QUANTAX 100 (EDX) (Bruker, Alemania). Se evaluó la homogeneidad de la morfología estructural, el tamaño del macroporo y microporo y la homogeneidad de los componentes. El análisis microscópico mostró microporos de 164,92 mm (± 35,032 mm) de diámetro en el área externa y microporos en el área interna de 54,44 mm (± 17,676 mm). La formación de porosidades e irregularidades presentes en el bloque fue heterogénea entre las superficies externas e internas. El contenido mineral de los bloques presentó homogeneidad con la presencia de carbono (2,02 %), oxígeno (44,33 %), fosfato (16,62 %) y calcio (37,87 %). El bloque β-TCP se puede utilizar en la reconstrucción ósea, pero la presencia de macroporos y tamaños de microporos reducidos podría limitar la eficacia en la fase de sustitución y regeneración ósea.

TMJ function after partial condylectomy in active mandibular condylar hyperplasia.

Condylar hyperplasia is a frequent pathology that causes severe facial asymmetries. The partial condylectomy generally halts the disease. The aim of this research was to examine post-condylectomy TMJ function; 14 patients were included in this study, 6 male and 8 female. The average age was 21 years old. In all, the partial condylectomy was performed with preauricular or endaural access and the osteotomy were performed with drills, saw or an ultrasonic system. The patients were assessed with 3 or more time after surgery and were considering maximum mouth opening, right and left lateralities, presence of pain, noises, alterations in the facial nerve (VII) and esthetic alteration from the scar. The analysis was performed with the visual analog scale (VAS) and with a 7 cm metallic rule. Data analysis was descriptive plus chi-square test considering p value < 0.05 for statistical differences. With an average of 11 month after surgery, the results showed that the open mouth (over 35 mm) and lateralities (average 9 mm for the both right and left side) were normal and without statistical differences between the right or left side. Noise was observed in 3 patients and pain was observed in two patients with level 2 and 1 (VAS score). Scar was not related to problem with patient and the temporal branch of facial nerve was observed with limitations but without problem for patients. It can be concluded that the condylectomy is a safe and effective procedure with low morbidity for patients.

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.

Osteosíntesis Bioreabsorbible Bioactivo (Hidroxiapatita/Poly L-lactido) en Osteotomía Le Fort I Segmentada / Bioresorbable Bioactive Osteosynthesys (Hidroxiapatite/Poly L-lactide) in Le Fort I Segmented Osteotomy

RESUMEN: El objetivo de este artículo es presentar un caso clínico con la utilización de un innovador sistema de osteosíntesis basado en la mezcla de hidroxiapatita (HA) y acido poliláctico (PLLA). La paciente fue admitida en el Hospital Abraham González Peña de Lautaro (Chile) debido a una deformidad facial que exigió realizar una cirugía ortognática monomaxilar para avance y aumento transversal del maxilar; se utilizaron placas de tipo L y tornillos de HA/PLLA de 5 mm para la fijación maxilar, realizando la cirugía sin complicaciones; el proceso técnico y alta hospitalaria se ejecutó de forma convencional. Se realizó un análisis de la literatura donde se analiza la versatilidad, la seguridad y la estabilidad de segmentos cuando se utiliza este innovador material y se concluye que este tipo de osteosíntesis es aplicable a cirugía maxilofacial, exigiendo una curva de aprendizaje por parte del cirujano, necesaria para obtener resultados adecuados.

ABSTRACT: The aim of this paper is to show a clinical case, where was used an innovative osteosynthesys system based on the mixture of hidroxiapatite (HA) and polilactic acid (PLLA). The patient was admitted into Abraham González Peña Hospital (Chile), showing a facial deformity to treat with monomaxillary orthognathic surgery for advance and transversal increase of the maxilla.; were used type L plates and 5 mm screws of HA/PLLA for the internal fixation, performing the surgery without complications; the technical process and the ALTA hospital was realized in a conventional strategy. Was realized a literature review showing the versatility, safe and stability of bone segment when used this innovative material and it´s concluded that this osteosynthesis system can be used normally in maxillofacial surgery; a learning curve to learn about this material is needed by surgeons.

[Relationship Between Condylar Size and Transverse Facial Asymmetry in Subject with Condylar Hyperplasia]. / Relación Entre el Tamaño Condilar y la Asimetría Facial Transversal en Individuos con Hiperplasia Condilar.

Facial asymmetry is a functional and esthetic pathology that can be related to condylar hyperplasia; the aim of this research was to asses the condylar size in the facial asymmetry. Twelve subjects was studies with cone beam computed tomography; the analysis was realized in the software Pax Zenith, Vatech (Korea 2011), using 90 kV and 120 mA and was realized anterior-posterior measurement, superior and inferior measurement and medial-lateral measurement of condylar head and was realized the relations with condylar position with the medial facial line and the position of facial point between superior central incisior, inferior central incisior and chin. The results show that the chin was displaced 6.5 mm from middle line being a hyperplasic condyle with a 2.7 mm more than no hyperplasic condyle. 1 mm of displacement of low central incisor was associated to 2.2 mm of chin displacement. The hyperplasic condyle presented more size and was posicionated 2 mm more lateral than non-hyperplasic condyle. Is conclude that the hyperplasic condyle present a clear influence in the facial transversal asymmetry and in possible to establish a relation between the size of hyperplasic condyle and the facial asymmetry.

Colgajos Microvascularizados en Reconstrucción Maxilofacial: Avances de la Microcirugía / Microvascularized flaps in Maxillofacial Reconstruction: Advances in Microsurgery

RESUMEN: La reconstrucción de la cabeza y el cuello contempla avances importantes a lo largo de los años. Los colgajos microvasculares se han convertido en la primera opción de tratamiento en grandes defectos del territorio maxilofacial, mientras tanto, la tecnología con el uso de microscopía y luego las imágenes como CT, angiografía por tomografía computarizada, dispositivo ultrasónico, RNM o Doppler contribuyen a lograr una predictibilidad excepcional de estos colgajos microvasculares. Por lo general, la técnica de anastomosis consiste en una sutura de 9-0 en 360°, pero existen autores que han descrito diversos métodos que no son de sutura con un rendimiento aceptable. Existe un buen número de diferentes colgajos microvasculares, cuatro de ellos son los más comunes en la reconstrucción maxilofacial: fíbula, ilíaco, antebrazo radial, escápula. Además el colgajo anterolateral, muy útil en defectos de piel y tejidos blandos. La evolución de los colgajos microvasculares implica los colgajos quiméricos, muy útiles en defectos grandes. El objetivo de este artículo es describir y exponer el desarrollo de la microcirugía y las diversas opciones de colgajos microvasculares en la reconstrucción maxilofacial.

ABSTRACT: Head and neck reconstruction have shown important advances over the years. Microvasculars flaps transfer has become the first treatment option in large defects of the maxillofacial area. Meanwhile technology through the use of microscopy and the subsequent use of images such as CT, CT angiography, RNM or Doppler ultrasonic device, and additional new techniques have contributed to an exceptional predictability of these microvascular flaps. Typically, the anastomosis technique consists in 9-0 suture in 360°, but since the vascular flaps exist, authors have described diverse non-suture methods with acceptable performance. There are a number of different microvasculars flaps, four of them are the most common in maxillofacial reconstruction: fibula, iliac, radial forearm, scapula. In addition the anterolateral tight flap, very useful in skin and soft tissues defects. The microvascular flaps evolution involves the chimeric flaps that are useful in large defects. The aim of this article is to describe and expose microsurgery development and the diverse microvascular flap options in maxillofacial reconstruction.

Cortical and cancellous bone in mandibular symphysis: implications in osteosynthesis and osteotomy / Hueso cortical y esponjoso en sínfisis mandibular: implicancias en osteotomía y osteosíntesis

The aim of this study was to quantify the presence of cortical and cancellous bone in the mandibular symphysis. A descriptive study was conducted using cone beam computed tomography where skeletal class I and class III subjects were included, defined according to characteristics detected on dental, clinical and dental occlusion x-rays. From the 3D reconstruction, sections were used in relation to the axial axis of the teeth of the anterior sector; the amount of buccal cortical, cortical, lingual, inferior cortical and cancellous bone as well as symphysis height were determined. The measurements were taken using routine methods and analyzed with ANOVA and Tukey's HSD test with p <0.05 for statistical significance. 20 skeletal class I subjects aged 23 years (± 4.5) and 20 class III subjects aged 22 years (± 5.2) were included. Symphysis height was significantly greater in skeletal class III subjects, exceeding by 0.8 mm the height of class I subjects; the buccal cortical bone presented on average 2 mm less at different dental levels, whereas the lingual cortical and inferior basal bones were significantly larger than the buccal cortical bone. The cancellous and cortical bones did not present any significant differences between the two groups (p=0.093). The buccal and basilar cortical bone is smaller than lingual cortical bone.

El objetivo fue determinar la presencia de hueso cortical y esponjoso en sínfisis mandibular. Se realizó un estudio descriptivo en tomografías computadorizadas cone beam donde se analizaron sujetos clase I y clase III esqueletal definidos según características dentales, clínicas y radiográficas de oclusión dental y características radiográficas. Desde la reconstrucción 3D se utilizaron cortes en relación al eje axial de los dientes del sector anterior; en ellos se determinó la cantidad de hueso cortical bucal, cortical, lingual, cortical inferior, hueso esponjoso y altura de sínfisis. Las mediciones fueron realizadas con métodos de rutina y fueron analizados con la prueba ANOVA y HDS Turkey considerando un valor de p <0.05 para considerar significancia estadística. 20 sujetos clase I esqueletal con 23 años (+ 4.5) y 20 sujetos clase III esqueletal con edad de 23 años (+ 4.5) fueron incluidos. La altura de sínfisis fue significativamente mayor en sujetos de clase III esqueletal, superando por 0.8 mm la altura de sujetos clase I; el hueso cortical bucal presento en promedio menor de 2 mm en diferentes niveles dentarios, mientras que la cortical lingual y basal inferior fueron significativamente mayor que la cortical bucal. El hueso esponjoso y hueso cortical no presentó diferencias significativas entre ambos grupos (p=0.093). La cortical bucal y basilar son menores que el hueso cortical lingual.

Modelo experimental para el estudio de la reconstrucción mandibular: opciones en conejos Oryctolagus cuniculus / Experimental model for the study of mandibular reconstruction: options in rabbits Oryctolagus cuniculus

El propósito de este estudio fue de evaluar la técnica quirúrgica propuesta para estudios de resección y reconstrucción mandibular en modelos experimentales en conejos. Se utilizaron 7 conejos neozelandeses (Orictolagus cuniculus), en los cuales se realizó la resección del cuerpo mandibular izquierdo, una vez asegurada la movilidad de los segmentos, se reconstruyó con placa de osteosíntesis de titanio de 1,5 mm y tornillos monocorticales de 5 mm, en la zona resecada se fijó un bloque de beta fosfato tricálcico y estabilizado con tornbillo de 1,2 mm. Se sacrificaron los animales a los 2 meses. Todos los animales sobrevivieron al procedimiento y se pudo llevar a cabo la resección y reconstrucción en todos ellos. No se presentaron signos ni síntomas de infección en el sitio quirúrgico mientras duró el experimento. El tiempo promedio de cirugía fue de 68 minutos. El peso promedio de los animales fue de 3925 g, la pérdida promedio de peso fue de 2,03 %. No se realizó eutanasia de ningún animal por motivos de sufrimiento. Al examen macroscópico de las muestras extraídas se observó la presencia de todos los elementos de osteosíntesis en posición, así como continuidad de la estructura ósea casi en su totalidad en la superficie . La utilización de conejos en modelos de reconstrucción maxilofacial es un modelo probado debido a la similitud de los procesos reparativos, su facilidad de manipulación y cuidados. El modelo propuesto representa una alternativa más cercana a los procesos reconstructivos en cirugía resectiva maxilofacial, debido a que somete los injertos a las fuerzas propias de la masticación y de la función orofacial.

The purpose of this study was to evaluate the surgical technique proposed for studies of resection and mandibular reconstruction in experimental models in rabbits. Seven rabbits (Orictolagus cuniculus) were used, in which the left mandibular body was resected, once the mobility of the segments was assured, reconstructed with 1.5 mm titanium osteosynthesis plate and monocortical screws of 5 mm, in the resected area a block of beta-tricalcium phosphate was stabilized and stabilized with tornbillo of 1.2 mm. The animals were sacrificed at 2 months. All animals survived the procedure, and resection and reconstruction were performed in all of them. There were no signs or symptoms of infection at the surgical site during the experiment. The average length of surgery was 68 minutes. The average weight of the animals was 3.925 g, the average weight loss was 2.03 %. No animal was euthanized for reasons of suffering. Macroscopic examination of the extracted samples showed the presence of all elements of osteosynthesis in position, as well as continuity of the bone structure almost entirely on the surface. The use of rabbits in models of maxillofacial reconstruction is a proven model due to the similarity of the reparative processes, their ease of manipulation and care. Our proposed model represents a closer alternative to the reconstructive processes in maxillofacial resective surgery, because it subjects the grafts to the forces of chewing and orofacial function.