Impact of general anesthesia on postoperative complications in orthognathic surgery: a retrospective comparison of total intravenous anesthesia versus volatile anesthesia.

Orthognathic surgery has a high incidence of postoperative nausea (PON) and vomiting (POV), delaying mobility initiation and postoperative recovery. Bleeding is another risk associated with this surgical procedure. We aimed to compare total intravenous anesthesia (TIVA) and volatile anesthesia in patients undergoing orthognathic surgery in terms of postoperative nausea and vomiting (PONV) incidence and hemodynamic changes. This retrospective study included 82 patients who underwent bilateral sagittal split ramus osteotomies at Saga University Hospital between April 2016 and April 2021. We compared the effects of TIVA and volatile anesthesia on PONV onset after surgery, acute postoperative hemodynamic changes (blood pressure and heart rate), and factors contributing to PONV. PON was significantly lower in the TIVA group than in the volatile anesthesia group. The total dose of fentanyl contributed to the onset of POV, while the onset of PON was associated with low volumes of fluid infusion and urine in the TIVA and volatile anesthesia groups, respectively. Furthermore, post-extubation hemodynamic change was significantly smaller in the TIVA group than in the volatile anesthesia group. Therefore, TIVA could have a reduced risk of PONV and hemodynamic changes in patients undergoing orthognathic surgery. Employing TIVA could mitigate perioperative complications and enhance patient safety.

3D evaluation model of facial aesthetics based on multi-input 3D convolution neural networks for orthognathic surgery.

BACKGROUND: Quantitative evaluation of facial aesthetics is an important but also time-consuming procedure in orthognathic surgery, while existing 2D beauty-scoring models are mainly used for entertainment with less clinical impact. METHODS: A deep-learning-based 3D evaluation model DeepBeauty3D was designed and trained using 133 patients' CT images. The customised image preprocessing module extracted the skeleton, soft tissue, and personal physical information from raw DICOM data, and the predicting network module employed 3-input-2-output convolution neural networks (CNN) to receive the aforementioned data and output aesthetic scores automatically. RESULTS: Experiment results showed that this model predicted the skeleton and soft tissue score with 0.231 ± 0.218 (4.62%) and 0.100 ± 0.344 (2.00%) accuracy in 11.203 ± 2.824 s from raw CT images. CONCLUSION: This study provided an end-to-end solution using real clinical data based on 3D CNN to quantitatively evaluate facial aesthetics by considering three anatomical factors simultaneously, showing promising potential in reducing workload and bridging the surgeon-patient aesthetics perspective gap.

Bone microstructural characteristics or positional changes of condyle head affect short-term condyle head resorption after orthognathic surgery.

Condylar resorption occurs in some cases after orthognathic surgery, and the risk factors associated with postoperative condylar head resorption have been extensively described. Nevertheless, even in cases with a combination of risk factors, postoperative condylar resorption may not appear. This study analyzed the microstructure and three-dimensional positional change of the condylar bone via imaging in patients who have undergone bimaxillary orthognathic surgery to determine whether the microstructure or condylar position differs between patients with and without postoperative condylar resorption. Among asymptomatic patients who underwent bimaxillary surgery between April 2021 and March 2022 at our department, 17 patients were analyzed, limited to "female," "skeletal Class II," and "high-angle cases," which are known risk factors for mandibular head resorption. Multidetector computed tomography was performed on these patients before and 6 months after surgery, and the bone microstructure of the condylar head and the three-dimensional positional changes of the condylar bone and the proximal bony fragments were compared with the presence of postoperative condyle resorption using the bone morphology software TRI/3D-BON. Patients with condylar bone abnormalities before surgery and those with high trabecular bone density can develop postoperative resorption if the condyle is misaligned by surgery.

Nasal septum-derived chondroprogenitor cells control mandibular condylar resorption consequent to orthognathic surgery: a clinical trial.

Condylar resorption is an aggressive and disability form of temporomandibular joint (TMJ) degenerative disease, usually non-respondent to conservative or minimally invasive therapies and often leading to surgical intervention and prostheses implantation. This condition is also one of the most dreaded postoperative complications of orthognathic surgery, with severe cartilage erosion and loss of subchondral bone volume and mineral density, associated with a painful or not inflammatory processes. Because regenerative medicine has emerged as an alternative for orthopedic cases with advanced degenerative joint disease, we conducted a phase I/IIa clinical trial (U1111-1194-6997) to evaluate the safety and efficacy of autologous nasal septal chondroprogenitor cells. Ten participants underwent biopsy of the nasal septum cartilage during their orthognathic surgery. The harvested cells were cultured in vitro and analyzed for viability, presence of phenotype markers for mesenchymal stem and/or chondroprogenitor cells, and the potential to differentiate into chondrocytes, adipocytes, and osteoblasts. After the intra-articular injection of the cell therapy, clinical follow-up was performed using the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) and computed tomography (CT) images. No serious adverse events related to the cell therapy injection were observed during the 12-month follow-up period. It was found that autologous chondroprogenitors reduced arthralgia, promoted stabilization of mandibular function and condylar volume, and regeneration of condylar tissues. This study demonstrates that chondroprogenitor cells from the nasal septum may be a promise strategy for the treatment of temporomandibular degenerative joint disease that do not respond to other conservative therapies.

The online attention analysis on orthognathic surgery research.

OBJECTIVES: Altmetrics is one of the fields of bibliometrics that seeks to assess the impact and interest of a given subject through Internet users. The aim of this study is to make an altmetric analysis of the orthognathic surgery literature. METHODS: A literature search was conducted using Dimensions app up to December 2023. A list of the 100 most mentioned articles on the topic was compiled. A Google Trends search was performed with same strategy to visualize important data regarding internet search. Charts and tables were created using Microsoft Excel and VOSviewer software to allow bibliometric visualization. RESULTS: There was a very poor correlation between the number of mentions and the number of citations (r = 0.0202). Most articles discussed on technical innovations associated to orthognathic surgery, majority related to virtual planning (n = 26). Other topics considered interesting to internet readers were complications (n = 18), surgical technique (n = 14), and psychological aspects/quality of life (n = 13). CONCLUSION: Online interest in orthognathic surgery closely aligns with the level of academic interest but is also influenced by factors such as location and economic status. The internet is a powerful tool for disseminating scientific research to a broad audience, making it more accessible and engaging than traditional academic channels.

Body mass index and weight loss in patients submitted to orthognathic surgery: a prospective study.

OBJECTIVE: To compare the body mass index (BMI) and the weight loss (WL) in patients with dentofacial deformities who underwent monomaxillary versus bimaxillary orthognathic surgery. MATERIALS AND METHODS: This prospective longitudinal study included 69 patients with dentofacial deformities who underwent surgical orthodontic treatment. Patients were divided into two groups according to the type of orthognathic surgery: monomaxillary or bimaxillary. A preoperative nutritional assessment based on BMI was performed; the percentage of involuntary WL between the preoperative and postoperative periods was also calculated. Data were collected at preoperative and 10, 40, and 90 days postoperative (PO). Statistical analysis was performed using SPSS 17.0 (IBM Corp., Armonk, NY, USA), and data are reported with 95% confidence interval. RESULTS: According to BMI, patients who underwent monomaxillary surgery presented: underweight = 2.6%, normal weight = 51.3%, overweight = 35.9%, and obese = 10.3%. The subjects who underwent bimaxillary surgery presented: normal weight = 43.3%, overweight = 36.7%, and obese = 20%. BMI was similar between the groups at all time points (preoperative, p= 0.237; 10 days PO, p= 0.325; 40 days PO, p= 0.430; and 90 days PO, p= 0.609). All patients lost weight postoperatively, and WL was similar among the PO measurements (p= 0.163). CONCLUSIONS: Although both monomaxillary and bimaxillary orthognathic surgeries resulted in WL and lower BMI, there was no statistically significant difference in these metrics between the two types of surgery.

Plication of the Suprahyoid Muscles Concomitant with Genioplasty to Improve the Aesthetics of the Submandibular Region / Plicatura de los Músculos Suprahioideos Concomitante con Genioplastia para Mejorar la Estética de la Región Submandibular

In addition to functionally correcting skeletal facial deformities, orthognathic surgery also has a great impact on aesthetics and facial proportions. However, patients who have soft tissue changes, such as tissue flaccidity, may not achieve an ideal result, and require complementary surgical techniques that promote aesthetic refinement. The literature on less invasive techniques is limited, and therefore, this work aims to report a surgical technique performed concomitantly with genioplasty to refine the harmony of the submandibular region, in a simple and effective way. Patient with skeletal class II deformity, with lack of mandibular definition and submandibular flaccidity, underwent bimaxillary advancement orthognathic surgery with advancement genioplasty to correct chin retrusion. Due to limited results with bone repositioning alone, plication of the suprahyoid musculature was performed in association with the same approach used in the genioplasty. As a result, there was traction in the cervical region, with a consequent decrease in the submental-cervical angle and improvement in submandibular aesthetics. Furthermore, there was no need for extensive surgical intervention and no impairment of the functional results of the orthognathic surgery itself. Therefore, it can be concluded that plication of the suprahyoid musculat ure concomitantly with genioplasty is a technique that promotes aesthetic gains in the cervical region.

Además de corregir funcionalmente las deformidades faciales esqueléticas, la cirugía ortognática también tiene un gran impacto en la estética y las proporciones faciales. Sin embargo, los pacientes que tienen cambios en los tejidos blandos, como la flacidez, pueden no lograr un resultado ideal y requieren técnicas quirúrgicas complementarias que promuevan el refinamiento estético. La literatura sobre técnicas menos invasivas es limitada, por lo que este trabajo tiene como objetivo reportar una técnica quirúrgica realizada concomitantemente con la genioplastia para refinar la armonía de la región submandibular, de manera simple y efectiva. Se trató a un paciente con deformidad esquelética clase II, con falta de definición mandibular y flacidez submandibular, intervenida de cirugía ortognática de avance bimaxilar con genioplastia de avance para corregir la retrusión del mentón. Debido a los resultados limitados solo con el reposicionamiento óseo, se realizó la plicatura de la musculatura suprahioidea en asociación con el mismo abordaje utilizado en la genioplastia. Como resultado, hubo tracción en la región cervical, con la consiguiente disminución del ángulo submentoniano-cervical y mejoría en la estética submandibular. Además, no hubo necesidad de una intervención quirúrgica extensa ni deterioro de los resultados funcionales de la cirugía ortognática en sí. Por lo tanto, se puede concluir que la plicatura de la musculatura suprahioidea concomitantemente con la genioplastia es una técnica que promueve ganancias estéticas en la región cervical.

Mechanical Evaluation of Different Stable Internal Fixation Techniques of Sagittal Osteotomy in Mandibular Advance / Evaluación Mecánica de Diferentes Técnicas de Fijación Interna Estable de Osteotomía Sagital en Avance Mandibular

The mandibular advancements performed in orthognathic surgeries can be stabilized with several techniques when using stable internal fixation. This study aims to comparatively evaluate, in vitro, the mechanical strength in a polyurethane mandibular model for four fixation techniques for sagittal split ramus osteotomy mandibular. 60 samples were divided into 4 groups, with 15 units for each group: group A, group B, group C and group D. Advances of 5 mm were made for each subgroup and fixed with 2.0 mm system plates and monocortical screws in the replicas of human hemimandibles in polyurethane resin. The samples were submitted to mechanical tests of linear loading, being evaluated the peak load and peak deformation. Technique B presented higher peak load (Kgf) and techniques A and B presented higher peak strain (p<0.05). Technique D presented lower peak load and lower peak strain (p<0.05). It is concluded that the study based on the development of new techniques for fixation for sagittal osteotomy of the mandibular ramus is of great importance for the advancement of orthognathic surgery, provided by the technical innovation of more favorable plate models.

Los avances mandibulares realizados en cirugías ortognáticas pueden estabilizarse con varias técnicas cuando se utiliza fijación interna estable. Este estudio tuvo como objetivo evaluar comparativamente, in vitro, la resistencia mecánica en un modelo mandibular de poliuretano para cuatro técnicas de fijación para la osteotomía sagital de la rama mandibular. Se dividieron 60 muestras en 4 grupos, con 15 unidades para cada grupo: grupo A, grupo B, grupo C y grupo D. Se realizaron avances de 5 mm para cada subgrupo y se fijaron con placas de sistema de 2,0 mm y tornillos monocorticales en las réplicas de hemimandíbulas humanas en resina de poliuretano. Las muestras fueron sometidas a pruebas mecánicas de carga lineal, siendo evaluadas la carga máxima y la deformación máxima. La técnica B presentó mayor pico de carga (Kgf) y las técnicas A y B presentaron mayor pico de deformación (p<0,05). La técnica D presentó menor carga máxima y menor tensión máxima (p<0,05). Se concluye que el estudio basado en el desarrollo de nuevas técnicas de fijación para la osteotomía sagital de la rama mandibular es de gran importancia para el avance de la cirugía ortognática, proporcionada por la innovación técnica de modelos de placas más favorables.

Manejo quirúrgico de bad split bilateral en cirugía ortognática / Surgical management of bilateral bad split during orthognathic surgery

El bad split es un término clínico que refiere a una fractura no planificada que ocurre al momento de realizar una osteotomía sagital de rama mandibular (OSRM). Afecta aproximadamente al 2,3% de los pacientes y se han descrito factores de riesgo tales como la presencia de terceros molares mandibulares, edad avanzada al momento de la cirugía, técnica de osteotomía inadecuada, entre otros. Se recomienda efectuar manio-bras preventivas para evitar la aparición de patrones de fractura no deseados al realizar la OSRM. Sin embargo, al momento de pesquisar un bad split, éste debe ser tratado por un equipo capacitado y de manera oportuna para evitar retardo en la consolidación, infecciones y secuestros óseos que puedan comprometer los resultados de la cirugía. En este artículo se presenta el manejo de un caso clínico de bad split bilateral intraoperatorio por el Servicio de Cirugía Maxilofacial del Hospital San José, enfatizando su tratamiento quirúrgico.

Bad Split is a clinical term referring to an unplanned fracture that occurs during the bilateral sagittal split osteotomy (BSSO). It affects approximately 2,3% of the patients undergoing orthognathic surgery and several risk factors have been described such as the presence of mandibular third molars, advanced age at the moment of orthognathic surgery, inadequate osteotomy technique, etc. Preventive maneuvers are recommended in order to avoid the appearance of undesired fracture patterns during BSSO. However, if a bad split is detected it must be managed and treated by a qualified team to avoid further complications such as delayed bone consolidation, bone infection and necrosis. In this article we present the management of a case of bilateral bad split by the Maxillofacial Surgery Service of Hospital San José, emphasizing on its surgical treatment.

Tratamiento integral de la clase III esquelética severa, mordida abierta y asimetría facial / Comprehensive treatment of severe skeletal class III, open bite and facial asymmetry

Introducción: La cirugía ortognática está especialmente indicada en casos complejos, donde los procedimientos conservadores fracasan o son insuficientes. El diagnóstico, planificación y tratamiento deben estar a cargo de un equipo multidisciplinario que trabaje en estrecha relación. Objetivo: Reportar el trabajo multidisciplinario en el tratamiento ortodóncico quirúrgico de una desarmonía dentomaxilofacial compleja. Presentación de caso: Paciente masculino, 19 años de edad, mestizo, clase III esquelética grave, hiperdivergente con mordida abierta y asimetría del tercio inferior, que recibió tratamiento prequirúrgico descompensador de ortodoncia. Se realizó cirugía ortognática bimaxilar con genioplastia de ascenso. Conclusiones: El tratamiento de las desarmonías dentomaxilofaciales es complejo y necesita la concurrencia de varias especialidades. Para la resolución del presente caso fue necesario el trabajo coordinado y simultáneo de especialistas de ortodoncia, prótesis dental, cirugía maxilofacial, periodoncia, psicología y otorrinolaringología. Se alcanzaron resultados estéticos y funcionales acorde a los objetivos del tratamiento propuestos y hubo estabilidad un año después de la cirugía(AU)

Introduction: Orthognathic surgery is especially indicated in complex cases, where conservative procedures fail or are insufficient. Diagnosis, planning and treatment should be carried out by a multidisciplinary team that works closely together. Objective: Report the multidisciplinary work in the surgical orthodontic treatment of a complex dentomaxillofacial disharmony. Case presentation: Male patient, 19 years old, mestizo, severe skeletal class III, hyperdivergent with open bite and asymmetry of the lower third, who received presurgical treatment decompensating orthodontics. Bimaxillary orthognathic surgery was performed with ascent genioplasty. Conclusions: The treatment of dentomaxillofacial disharmonies is complex and requires the concurrence of several specialties. For the resolution of this case, the coordinated and simultaneous work of specialists in orthodontics, dental prostheses, maxillofacial surgery, periodontics, psychology and otolaryngology was necessary. Aesthetic and functional results were achieved according to the proposed treatment objectives and there was stability one year after surgery(AU)

Tratamiento ortodóncico-quirúrgico de pacientes con asimetría facial / Orthodontic-surgical treatment of patients with facial asymmetry

Introducción: la asimetría facial es una condición notoria en el tercio inferior de la facie del sujeto y entre los tercios medio y superior, en este último será menos evidente esta condición, de tal manera que podría considerarse como una de las molestias de mayor incidencia en pacientes con necesidades o no de terapia or- todóncica. Objetivo: evaluar mediante una revisión de la literatura los tratamientos ortodóncico-quirúrgicos de pacientes con asimetría facial. Material y métodos: la literatura se seleccionó mediante una búsqueda en las bases de datos electrónicas: PubMed, Scopus, Web of Science. Las palabras clave utilizadas fueron: facial asymmetry, asymmetry, surgical treatment, surgical orthodontic treatment. La búsqueda se restringió a artículos en inglés publicados del año 2011 al 2021. Resultados: después de aplicar los criterios de inclusión y exclusión en total se obtuvieron y revisaron 27 artículos. Se realizó la revisión de literatura del tratamiento ortodóncico-quirúrgico en pacientes con asimetría facial. Conclusión: es preciso el abordaje ortodóntico quirúrgico para la corrección de la asimetría facial, del protocolo dependerá la situación clínica y la elección de tratamiento ortodóntico quirúrgico, lo que brindará mejoras significativas en la simetría facial (AU)

Introduction: facial asymmetry, is a notorious condition in the lower third of the subject's facie and between the middle and upper thirds, in the latter this condition will be less evident; in such a way, it could be considered as one of the discomforts of greater incidence in patients with needs or not of orthodontic therapy. Objective: to evaluate by means of a literature review the orthodontic-surgical treatment of patients with facial asymmetry. Material and methods: the literature was selected through a search in the following electronic databases: PubMed, Scopus, Web of Science. The keywords used were: facial asymmetry, asymmetry, surgical treatment, surgical orthodontic treatment. The search was restricted to articles in English published from 2011 to 2021. Results: after applying the inclusion and exclusion criteria, a total of 27 articles were obtained and reviewed. The literature review of orthodontic-surgical treatment in patients with facial asymmetry was performed. Conclusion: surgical orthodontic approach is necessary for the correction of facial asymmetry, the protocol will depend on the clinical situation, the choice of surgical orthodontic treatment, which will give significant improvements in facial symmetry (AU)

Application of three-dimensional technology in orthognathic surgery: a narrative review.

With the recent advances in three-dimensional (3D) technology, orthognathic surgery has steadily evolved, gradually performing more sophisticated surgery and expanding its scope of application. The objective of this study is to summarize the current evidence of the application of 3D technology in the field of orthognathic surgery, with the hope of providing helpful information for practitioners who are interested in orthognathic surgery. Peer-reviewed articles published in English were retrieved from literature through an extensive search performed in PubMed/MEDLINE. The application of 3D technology in orthognathic surgery can be summarized from the aspects of preoperative diagnosis, surgical planning, surgical procedure and postoperative evaluation. There is evidence that supports the use of 3D technology, including cone beam computed tomography (CBCT), 3D imaging devices, 3D printing technology, navigation, computer-aided design and computer-aided manufacturing (CAD/CAM), can help improving orthognathic surgery and achieving promising outcomes. Even though there may be an added cost, the application of 3D technology has provided decreased operative time and hospital length of stay, which is positive for both practitioners and patients. With precision and minimal invasiveness, 3D technology is considered to be an effective method in exploring more scientific and reasonable programs and procedures of orthognathic surgery.

Tratamiento multidisciplinario del exceso vertical total y deficiencia transversal del maxilar sin mordida cruzada posterior / Multidisciplinary treatment of total vertical excess and transverse maxillary deficiency without posterior crossbite

Introducción: La corrección del exceso vertical del maxilar traerá no solo cambios verticales en el perfil, sino también sagitales y transversales. La ausencia clínica de mordida cruzada posterior puede enmascarar deficiencias del ancho y provocar planes de tratamiento incorrectos. Objetivo: Describir los aspectos más importantes en la atención de un caso con exceso vertical y deficiencia transversal del maxilar sin mordida cruzada posterior. Presentación de caso: Paciente femenina de 26 años de edad acude a consulta por "dientes hacia adelante". El examen físico y el estudio de los medios diagnósticos permitieron concluir la existencia de exceso vertical y deficiencia transversal del maxilar. Clínicamente no se observó mordida cruzada posterior. El tratamiento por etapas incluyó ortodoncia, expansión e impactación quirúrgica del maxilar. Conclusiones: El ascenso quirúrgico del maxilar debe planificarse a partir de un análisis holístico. Incluye los cambios sagitales del perfil y de la relación transversal entre las arcadas, provocados por el efecto de rotación mandibular. La ausencia de mordida cruzada posterior no excluye la existencia de deficiencia transversal del maxilar. Asimismo, la dimensión definitiva de la expansión debe establecerse una vez que la arcada inferior alcance sus dimensiones definitivas(AU)

Introduction: The correction of the vertical excess of the maxilla will bring not only vertical changes in the profile, but also sagittal and transverse ones. The clinical absence of posterior crossbite can mask width deficiencies and lead to incorrect treatment plans. Objective: Describe the most important aspects in the care of a case with vertical excess and transverse deficiency of the maxilla without posterior cross bite. Case presentation: A 26-year-old female patient comes to the consultation for "teeth forward". The physical examination and the study of the diagnostic means allowed to conclude the existence of vertical excess and transverse deficiency of the maxilla. Clinically, no posterior crossbite was observed. Staged treatment included orthodontics, expansion and surgical impaction of the maxilla. Conclusions: The surgical ascent of the maxilla should be planned based on a holistic analysis. It includes the sagittal changes of the profile and the transverse relationship between the arcades, caused by the effect of mandibular rotation. The absence of posterior crossbite does not exclude the existence of transverse maxillary deficiency. Likewise, the definitive dimension of the expansion must be established once the lower arcade reaches its definitive dimensions(AU)

Condylar repositioning according to digital bite registration method for virtual orthognathic surgery planning: A series of 49 consecutive patients.

INTRODUCTION: The accurate mandibular condylar positioning for orthognathic surgical planning is fundamental in obtaining a planned occlusal result. The differences between the position of condyles seen on computed tomography or cone-beam computed tomography (CBCT) scans and during surgery reduce the accuracy of the result. This study aimed to assess the differences between the condylar position recorded on CBCT and a numerical 3-dimensional (3D) model created after mandibular repositioning for orthognathic surgery planning. METHODS: This study retrospectively evaluated 49 patients who underwent virtual orthognathic surgery planning. The procedure involved recording a computed tomography or CBCT of the skull and dental surface using an intraoral digital scanner. The mandible was repositioned on the numerical 3D model according to the superimposed virtual bite registration in centric relation. Linear and angular measurements of the right and left condyles were recorded before and after mandibular repositioning. RESULTS: The positions of 98 condyles were compared. Linear measurements of the posterior and superior joint spaces revealed a significant difference. Subgroup analyses displayed statistically significant differences for patients with skeletal Class II malocclusion. CONCLUSION: According to the digital bite registration method, the difference between the mandibular position recorded on CBCT and on the numerical 3D model after repositioning may have clinical significance. Further studies are needed to validate this theory and test the accuracy of the clinical results.

Discrepancia negativa transversal del maxilar y factores asociados en pacientes con necesidad de cirugía ortognática / Negative transverse maxillary discrepancy and associated factors in patients requiring orthognathic surgery

Introducción: La discrepancia transversal de las arcadas es un problema esquelético poco estudiado en personas con necesidad de tratamiento ortodóncico quirúrgico. Objetivo: Caracterizar a pacientes con discrepancia negativa transversal del maxilar y necesidad de tratamiento por cirugía ortognática. Métodos: Se realizó un estudio descriptivo de corte transversal en 25 expedientes clínicos de pacientes que acudieron al servicio de cirugía maxilofacial del Hospital Clínico Quirúrgico Hermanos Ameijeiras, con discrepancia negativa transversal del maxilar y necesidad de cirugía ortognática entre enero de 2016 y enero de 2020. Se estudiaron los casos por medio de variables cualitativas divididas en epidemiológicas, características faciales y mediciones dentarias. Para el análisis se confeccionaron cuadros estadísticos y como medidas de resumen se utilizaron frecuencias absolutas y relativas. Resultados: La frecuencia de la discrepancia negativa del maxilar fue de 13,3 por ciento. Los pacientes de piel blanca fueron los más afectados (80 por ciento) y el principal motivo de consulta fue estético (68 por ciento). La asimetría del tercio inferior y el perfil cóncavo estuvieron presentes en el 44 por ciento y 36 por ciento de los casos respectivamente. Se observó alta frecuencia de pacientes con el tercio inferior aumentado (76 por ciento), mordida cruzada posterior (48 por ciento), mordida abierta anterior (75 por ciento), apiñamiento en la arcada inferior (63,3 por ciento) y lingualización del incisivo inferior (72 por ciento). Conclusiones: La discrepancia negativa transversal del maxilar es frecuente en personas con necesidad de cirugía ortognática y con gran afectación estética. Se observó mayor predisposición a padecerla en pacientes de piel blanca(AU)

Introduction: Transverse discrepancy of the arches is a skeletal problem not sufficiently studied in persons requiring surgical orthodontic treatment. Objective: Characterize patients with negative transverse maxillary discrepancy requiring surgical orthognathic surgery. Methods: A descriptive cross-sectional study was conducted of 25 medical records of patients attending the maxillofacial surgery service at Hermanos Ameijeiras Clinical Surgical Hospital with negative transverse maxillary discrepancy requiring orthognathic surgery from January 2016 to January 2020. The cases were studied with qualitative variables divided into epidemiological, facial features and dental measurements. Analysis was based on statistical charts. The summary measurements used were absolute and relative frequencies. Results: The frequency of negative maxillary discrepancy was 13.3 percent. White skin patients were more commonly affected (80 percent). The main concern was aesthetic (68 percent). Lower third asymmetry and a concave profile were present in 44 percent and 36 percent of the cases, respectively. A high frequency was observed of patients with an augmented lower third (76 percent), posterior crossbite (48 percent), anterior open bite (75 percent), lower arch crowding (63.3 percent) and lower incisor lingualization (72 percent). Conclusions: Negative transverse maxillary discrepancy is common among patients requiring orthognathic surgery for large aesthetic alterations. White skin patients were found to be more prone to present this disorder(AU)

Discrepancia negativa transversal del maxilar y diferencias cefalométricas laterales según el ancho de la arcada superior / Negative maxillary transverse discrepancy and cephalometric lateral differences according to the width of upper arch

Introduction: Negative maxillary transverse discrepancy is not exclusive to narrow upper arch. The transverse discrepancy due to maxillary deficiency is well described, but this is not the case when the maxilla displays adequate dimensions and the origin of the problem is an excess of mandibular width. Objective: To describe the cephalometric characteristics of negative maxillary transverse discrepancy present in narrow upper arches with those of normal or increased width. Methods: An observational and cross-sectional study was carried out in records of patients with negative maxillary transverse discrepancy. The cases referred to the maxillofacial surgery department at Hospital Clínico Quirúrgico "Hermanos Ameijeiras" between January 2016 and January 2020 were selected. The initial study models were measured and two groups were formed: those with a distance between central fossae of 16 to 26, less than 47 mm and the other with equal or greater values. Lateral cephalometric analysis of Ricketts, McNamara, Björk & Jarabak, Burstone and soft profile were performed on the initial teleradiographs. Using the Mann Whitney U test of independent samples, measurements with statistically significant differences between both groups were selected. (p <0.05). Results: Significant differences were found regarding the cranial-mandibular relationship, mandibular anatomy, maxillo-mandibular relationship and occlusal relationship. The most important differences observed in each group were respectively: S-Ar / Ar-Go ratio (p = 0.033), mandibular body length (p = 0.01), mandibular-maxillary difference (p = 0.003) and overjet (p = 0.043). Conclusions: In the studied patients, negative maxillary transverse discrepancy has the same probability of presenting a wide or in norm upper arch, as well as a narrow arch. In the first case, it is more likely to find jaws with increased body length, a skeletal class III pattern and a concave profile; in the second case, the tendency is to present small jaws with increased articular angle and dental overjet(AU)

Introducción: La discrepancia negativa transversal del maxilar no es exclusiva de una arcada superior angosta. La discrepancia transversal por deficiencia maxilar está bien descrita, pero no ocurre así cuando el maxilar se presenta con dimensiones adecuadas y el origen del problema es un exceso del ancho mandibular. Objetivo: Describir las diferencias cefalométricas de la discrepancia negativa transversal del maxilar que presentan arcadas superiores estrechas con aquellas de ancho normal o incrementado. Métodos: Se realizó un estudio observacional, de corte transversal, en expedientes de pacientes con discrepancia negativa transversal del maxilar. Se seleccionaron los casos que acudieron entre enero del 2016 y enero del 2020 a la consulta de cirugía maxilofacial del Hospital Clínico Quirúrgico "Hermanos Ameijeiras". Se midieron los modelos de estudio iniciales y se conformaron dos grupos: aquellos con distancia entre fosas centrales de 16-26, menor de 47 mm y el otro con valores iguales o superiores. Se realizaron análisis cefalométricos laterales en las telerradiografías iniciales de Ricketts, McNamara, Björk & Jarabak, Burstone y perfil blando. Por medio de la prueba U de Mann Whitney de muestras independientes, se seleccionaron las mediciones con diferencias estadísticas significativas entre ambos grupos (p < 0.05). Resultados: Se encontraron diferencias significativas concernientes a la relación cráneo mandibular, anatomía mandibular, relación máxilo mandibular y relación oclusal. Las diferencias observadas más importantes de cada grupo fueron respectivamente: relación S-Ar/Ar-Go (p = 0,033), longitud del cuerpo mandibular (p = 0,01), diferencia mandibular-maxilar (p = 0,003) y resalte (p = 0,043). Conclusiones: En los pacientes estudiados, las discrepancias negativas transversales tienen la misma probabilidad de presentarse con la arcada superior ancha o en norma, que angosta. En los primeros es más probable encontrar mandíbulas con longitud del cuerpo incrementada, patrón de clase III esquelética y perfil cóncavo; en los segundos, la tendencia es a presentar mandíbulas pequeñas con ángulo articular y resalte dentario aumentados(AU)

Development of novel artificial intelligence systems to predict facial morphology after orthognathic surgery and orthodontic treatment in Japanese patients.

From a socio-psychological standpoint, improving the morphology of the facial soft-tissues is regarded as an important therapeutic goal in modern orthodontic treatment. Currently, many of the algorithms used in commercially available software programs that are said to provide the function of performing profile prediction are based on the false assumption that the amount of movement of hard-tissue and soft-tissue has a proportional relationship. The specification of the proportionality constant value depends on the operator, and there is little evidence to support the validity of the prediction result. Thus, the present study attempted to develop artificial intelligence (AI) systems that predict the three-dimensional (3-D) facial morphology after orthognathic surgery and orthodontic treatment based on the results of previous treatment. This was a retrospective study in a secondary adult care setting. A total of 137 patients who underwent orthognathic surgery (n = 72) and orthodontic treatment with four premolar extraction (n = 65) were enrolled. Lateral cephalograms and 3-D facial images were obtained before and after treatment. We have developed two AI systems to predict facial morphology after orthognathic surgery (System S) and orthodontic treatment (System E) using landmark-based geometric morphometric methods together with deep learning methods; where cephalometric changes during treatment and the coordinate values of the faces before treatment were employed as predictive variables. Eleven-fold cross-validation showed that the average system errors were 0.94 mm and 0.69 mm for systems S and E, respectively. The total success rates, when success was defined by a system error of < 1 mm, were 54% and 98% for systems S and E, respectively. The total success rates when success was defined by a system error of < 2 mm were both 100%. AI systems to predict facial morphology after treatment were therefore confirmed to be clinically acceptable.

A cirurgia ortognática no tratamento da DTM em pacientes classe II / The orthognatic surgery in treatment of TMJ in class II patients

Introdução: A má oclusão Classe II pode influenciar negativamente na qualidade de vida dos pacientes, tanto na aparência facial, quanto função oral ou até ambas. Atualmente, o tratamento ortodôntico-cirúrgico é comumente utilizado em pacientes com discrepâncias esqueléticas graves. Objetivo: Este estudo tem como objetivo analisar os resultados da cirurgia ortognática associada ao tratamento ortodôntico nos pacientes que possuem DTM e má oclusão de Classe II por retrognatismo mandibular. Metodologia: Foi realizada uma pesquisa bibliográfica nas plataformas de buscas científicas Google Acadêmico, CAPES/MEC, PubMed/Medline, Scielo, Elsevier, e nas revistas AJO-DO (American Journal of Orthodontics and Dentofacial Orthopedics) e The Angle Orthodontist (An International Journal of Orthodontics and Dentofacial Orthopedics), utilizando as seguintes palavras chave: retrognatismo, cirurgia ortognática e transtornos da ATM. Conclusão: A maioria dos pacientes que apresentam sinais e sintomas de DTM pré-operatórios melhoram a disfunção e diminuem os níveis de dor com o tratamento ortognático. Além disso, o tratamento ortodôntico é de suma importância para se obter o sucesso do procedimento cirúrgico, assim como na estabilidade pós-cirúrgica.(AU)

Introduction: Class II malocclusion can negatively influence patients in quality of life, in the facial and oral appearance or both. Currently, orthodontic-surgical treatment is commonly used in patients with severe skeletal discrepancies. Objective: The objective of this study was to analyze the results of orthognathic surgery associated with orthodontic treatment in patients who have TMD and Class II malocclusion due to mandibular retrognathism. Methodology: A bibliographic search was performed in the scientific search platforms Google Scholar, CAPES/MEC, PubMed/Medline, Scielo, Elsevier, AJO-DO (American Journal of Orthodontics and Dentofacial Orthopedics) and in The Angle Orthodontist (An International Journal of Orthodontics and Dentofacial Orthopedics), using the keywords: retrognathism, orthognathic surgery and TMJ disorders. Conclusion: With orthognathic treatment, most patients who had preoperative DTM signs and symptoms showed an improvement and a decrease in pain levels. In addition, orthodontic treatment is important for the success of the surgical procedure, as well as for post-surgical stability.(AU)

Effect of continuous infusion of dexmedetomidine on blood loss in orthognathic surgery: a retrospective study.

BACKGROUND: Patients with maxillofacial deformities require orthognathic surgeries to correct occlusion. The surgical procedure may lead to massive bleeding, which is associated with haematoma, respiratory obstruction, and asphyxia. Dexmedetomidine has been used in controlled hypotension and may reduce blood loss in orthognathic surgery. We conducted a retrospective cohort study to evaluate the effect of dexmedetomidine on blood loss in orthognathic surgeries. METHODS: The primary outcome examined was blood loss, and secondary outcomes were postoperative haemoglobin level; intraoperative heart rate and blood pressure (T1: at incision; T2: 30 min after incision; T3: 60 min after incision; T4: 120 min after incision); dosage of fentanyl, remifentanil, urapidil, and esmolol; operation time; and incidence of allogeneic blood transfusion. RESULTS: A total of 1247 patients were included in this study, and 540 patient pairs were matched via propensity score matching. There were significant decreases in mean blood loss, heart rate at T1-T4, blood pressure at T1, and remifentanil and esmolol dosage in the dexmedetomidine group compared with those in the control group. There was also a significant increase in the postoperative haemoglobin level of the dexmedetomidine group. CONCLUSIONS: Continuous infusion of dexmedetomidine can decrease blood loss in orthognathic surgery. TRIAL REGISTRATION: ChiCTR1800018794 (retrospectively registered) Name of registry: Chinese Clinical Trial Registry Date of registration: 2018/10/09 URL: www.chictr.org.cn/showproj.aspx?proj=30612.