Anatomical Conditions in Simultaneous Orthognathic Surgery and Structural Rhinoplasty. A Clinical Series / Condiciones Anatómicas en Cirugía Ortognática y Rinoplastia Estructural Simultanea. Una Seria Clínica

SUMMARY: Orthognathic surgery and rhinoplasty show synergy in terms of function and aesthetic results. The aim of this research is to analyze variables related to simultaneous orthognathic surgery and rhinoplasty and to discuss the surgical sequence. Male and female subjects between 18 and 45 years old were included in this research. Diagnosis related to nasal morphology (nasal tip bifid, rotate, square and others as well as the alae morphology and columella), facial deformity (sagittal and vertical deformity), type of surgery (rhinoplasty techniques and orthognathic techniques) and complications were included. The minimum follow-up was 12 months; Chi- Square and t test were used to define correlations, considering a value of p<0.05 for statistical significance. Class III facial deformity was observed in 40 % of subjects and class II facial deformity was present in 43 %. For the nasal deformities, the tip and nasal bridge were most prevalent; primary nasal deformity was observed in the 83 % of subjects and was significant more than secondary nasal deformity (p=0.042). Bimaxillary surgery was performed in 31 cases (88 %). In 10 cases a change of the original plan for rhinoplasty due to previous maxillary surgery was realized, mainly in class III facial deformity, with no statistical differences. Revision rhinoplasty was realized in 5 cases (14 %) and was not related to surgical variables; revision for orthognathic surgery was not necessary in this series. Rhinoplasty and orthognathic surgery simultaneously show low complications and predictable results. We can conclude that maxillary mandibular osteotomies and rhinoplasty could be performed safely. However, larger studies are necessary to understand the best choice and variables involved in simultaneous procedures and soft tissue response.

La cirugía ortognática y la rinoplastia muestran sinergia en términos de resultados funcionales y estéticos. EL objetivo de esta investigación es analizar variables relacionadas con la cirugía ortognática y rinoplastia ejecutada de forma simultanea. Fueron incluidos hombres y mujeres entre 18 y 45 años de edad. EL diagnóstico fue en base a la morfología nasal (punta bífida, rotada, cuadrada u otras así como alteraciones del ala nasal y columela), deformidad facial (deformidad sagital y vertical), tipo de cirugía (técnica de rinoplastia y cirugía ortognática) y complicaciones asociadas. El seguimiento mínimo fue de 12 meses; se utilizo las prueba t test y chi cuadrado para definir relaciones estadísticas considerando un valor de p< 0,05 para obtener diferencias significativas. La deformidad clase III fue observada en el 40 % de los sujetos y la deformidad facial de clase II se presento en el 43 %. Para la deformidad nasal, las alteraciones de a punta nasal y nasal fueron mas prevalentes; la deformidad nasal primaria se presentó en el 83 % de los sujetos y fue significativamente mayor que la deformidad nasal secundaria (p=0,042). La cirugía bimaxilar se realizó en 31 casos (88 %); en 10 casos se realizó el cambio del plan quirúrgico inicial de la rinoplastia debido a cambios generados en la cirugía maxilar previa, mayormente en deformidad facial de clase III, sin presentar diferencias significativas. La rinoplastia de revisión fue realizada en 5 casos (14 %) y no fue relacionada con ninguna variable de tipo quirúrgica; la revisión de cirugía ortognática no fue realizada en ningún caso de esta serie. La rinoplastia y la cirugía ortognática simultanea mostraron bajas complicaciones y resultados predecibles. Se puede concluir que la osteotomía maxilo mandibular y la rinoplastia son seguras; sin embargo, estudios de mayor volumen son necesarios para entender la mejor opción y variables relacionadas con procedimientos simultáneos y la respuesta de tejidos blandos faciales.

Condylar Positional Changes in Skeletal Class II and Class III Malocclusions after Bimaxillary Orthognathic Surgery.

Orthognathic surgery is indicated to modify the position of the maxillomandibular structure; changes in the mandibular position after osteotomy can be related to changes in the position of the mandibular condyle in the articular fossa. The aim of this study was to determine changes produced in the mandibular condyle 6 months after orthognathic surgery. A cross-sectional study was conducted that included subjects who had undergone bimaxillary orthognathic surgery to treat dentofacial deformity of Angle class II (group CII) or Angle class III (group CIII). Standardized images were taken using cone-beam computed tomography 21 days before surgery and 6 months after surgery; measurement scales were used to identify the condylar position and its relations with the anterior, superior, and posterior joint spaces. The results were analyzed using the Shapiro-Wilk and Student's t-tests, while considering a value of p < 0.05 as indicating a significant difference. Fifty-two joints from 26 patients, with an average age of 27.9 years (±10.81), were analyzed. All subjects in both group CII and group CIII showed a significant change in the anterior, superior, and posterior joint spaces. However, postoperative changes in the position of the condyle in the articular fossa were not significant in the anteroposterior analysis. We conclude that orthognathic surgery causes changes in the sagittal position of the mandibular condyle in subjects with mandibular retrognathism and prognathism.

Retrospective Analysis of the Airway Space Changes in Dentofacial Deformity after Two-Jaw Orthognathic Surgery Using Cone Beam Computed Tomography.

Orthognathic surgery is used to modify anomalies in maxillomandibular position; this process can significantly affect the anatomy of the airway and cause functional changes. This study aims to define the impact of mandibular maxillary movement on the airway of subjects with dentofacial deformity. A retrospective study was conducted on subjects with Angle class II (CII group) and Angle class III (CIII group) dentofacial deformities. The subjects were treated via bimaxillary surgery; for all of them, planning was performed with software and 3D printing. Cone beam computed tomography (CBCT) was obtained 21 days before surgery and 6 months after surgery and was used for planning and follow-up with the same conditions and equipment. Was used the superimposition technique to obtain the maximum and minimum airway areas and total airway volume. The data were analyzed with the Shapiro-Wilk test and Student's t-test, while Spearman's test was used to correlate the variables, considering a value of p < 0.05. Thus, 76 subjects aged 18 to 55 years (32.38 ± 10.91) were included: 46 subjects were in CII group, treated with a maxillo-mandibular advancement, and 30 subjects were in the CIII group, treated with a maxillary advancement and a mandibular setback. In the CII group, a maxillary advancement of +2.45 mm (±0.88) and a mandibular advancement of +4.25 mm (±1.25) were observed, with a significant increase in all the airway records. In the CIII group, a maxillary advancement of +3.42 mm (±1.25) and a mandibular setback of -3.62 mm (±1.18) were noted, with no significant changes in the variables measured for the airway (p > 0.05). It may be concluded that maxillo-mandibular advancement is an effective procedure to augment the airway area and volume in the CII group. On the other hand, in subjects with mandibular prognathism and Angle class III operated with the maxillary advancement and mandibular setback lower than 4 mm, it is possible to not reduce the areas and volume in the airway.

Early Treatment of Unilateral Condylar Hyperplasia in Adolescents: Preliminary Results.

Facial asymmetry associated with unilateral condylar hyperplasia (UCH) is a rare disease. The aim of this study was to evaluate the clinical conditions of progressive facial asymmetry in young subjects treated with high condylectomy. A retrospective study was performed including nine subjects diagnosed with UCH type 1B and progressive facial asymmetry around 12 years old with an upper canine progressing towards dental occlusion. After an analysis and a decision of treatment, orthodontics began one to two weeks prior to the condylectomy (with a mean vertical reduction of 4.83 ± 0.44 mm). Facial and dental asymmetry, dental occlusion, TMJ status and an open/closing mouth were analyzed before surgery and in the final stage of treatment, almost 3 years after surgery. Statistical analyses were performed using the Shapiro-Wilk test and a Student's t-test considering a p value of <0.05. Comparing T1 (before surgery) and T2 (once orthodontic treatment was finalized), the operated condyle showed a similar height to that observed in stage 1 with a 0.12 mm difference in height (p = 0.8), whereas the non-operated condyle showed greater height increase with an average of 3.88 mm of vertical growth (p = 0.0001). This indicated that the non-operated condyle remained steady and that the operative condyle did not register significant growth. In terms of facial asymmetry in the preoperative stage, a chin deviation of 7.55 mm (±2.57 mm) was observed; in the final stage, there was a significant reduction in the chin deviation with an average of 1.55 mm (±1.26 mm) (p = 0.0001). Given the small number of patients in the sample, we can conclude that high condylectomy (approx. 5 mm), if performed early, especially in the mixed-dentition stage before full canine eruption, is beneficial for the early resolution of asymmetry and thus the avoidance of future orthognathic surgery. However, further follow-up until the end of facial growth is required.

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

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

TMJ Position in Symmetric Dentofacial Deformity.

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

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

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

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

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

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

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

The Airway Volume Related to the Maxillo-Mandibular Position Using 3D Analysis.

OBJECTIVE: The aim of this research was to compare three cephalometric analyses and their correlation with the airway volume in subjects with different skeletal classes using 2D and 3D images. Study Design. Cross-sectional descriptive study. Material and Method. Steiner, McNamara, and Ricketts analyses and the airway volume were compared in 115 subjects who were candidates for orthognathic surgery under diagnosis using cone beam computed tomography (CBCT); 46 males (40%) and 69 females (60%) were included. The sagittal positions of the maxilla and mandible, the angulation of the mandibular plane, the sagittal positions of the upper and lower incisors, measurements of the largest or shortest airway area, and the volume were compared using Spearman's test considering a p value < 0.05. RESULTS: Differences were observed between the Steiner and McNamara techniques for the sagittal position of the maxilla (p = 0.01). For mandibular angulation, there was a greater difference between values for Steiner and Ricketts techniques (p = 0.001). In the upper incisor, the results for McNamara and Ricketts techniques were significantly different (p = 0.004). Analysing the airway, subjects with a class II skeletal pattern had a smaller volume than those with a class III pattern (p = 0.034). CONCLUSION: It may be concluded that skeletal class II patients have a significantly smaller airway volume than class III patients. The skeletal parameter does not always relate to the airway volume; however, the high mandibular angle could be related to the airway conditions.

Relación Transversal, Vertical y Sagital en Sujetos con Deformidad Facial Candidatos a Cirugía Ortognática / Transverse, Vertical and Sagittal Relationship in Subjects with Facial Deformity Candidates for Orthognathic Surgery

RESUMEN: El objetivo de este estudio fue evaluar la relación entre la clase esqueletal sagital y las condiciones transversales o verticales en sujetos con deformidad facial sin presencia de asimetría facial; Se realizó un análisis cefalomét rico de la clase esqueletal sagital, transversal y vertical en 115 sujetos con indicaciones de cirugía ortognática. Se consideró algunos datos del análisis cefalométrico de Steiner y el análisis cefalométrico de Ricketts en sentido sagital para determinar la clase esqueletal facial. A nivel transversal se determinó la dimensión transversal facial, dimensión transversal maxilar y dimensión transversal mandibular. A nivel vertical se determinó la dimensión vertical oclusal y dimensión vertical total. Al comparar las mediciones transversales y verticales entre sujetos de sexo femenino y masculino, se observó que los hom- bres presentaban mayores dimensiones que las mujeres (p=0,0001) en todos los análisis realizados. Los sujetos clase III presentaron mayor dimensión transversal facial (p=0,0002) y transversal mandibular (p=0,001) que los sujetos clase II. Además, se observó que los sujetos clase III presentaban mayor dimensión vertical total (p=0,002) que los sujetos clase II; Es posible concluir que existe características faciales transversales y verticales que se pueden relacionar con la posición sagital de las estructuras maxilo-mandibulares.

ABSTRACT: The aim of this study is to evaluate the relationship between sagittal skeletal class and transverse or vertical conditions in subjects with facial deformity without presence of facial asymmetry; A comparative study was conducted between the results of the cephalometric analysis of the sagittal, transverse and vertical skeletal class in 115 subjects with indications for orthognathic surgery. The Steiner cephalometric analysis in the sagittal direction was used to determine the facial skeletal class and the Ricketts cephalometric analysis in the sagittal analysis. At the transverse level it was determined the facial transverse dimension, maxillary transverse dimension and mandibular transverse dimension. At a vertical level it is determined the occlusal vertical dimension and total vertical dimension. When comparing cross-sectional and vertical measurements between female and male subjects, it was observed that male subjects presented greater dimensions than female subjects (p=0.0001). Class III subjects present greater facial transverse dimension (p=0.0002) and mandibular transverse dimension (p=0.001) than class II subjects. Also, it was observed that class III subjects had a greater total vertical dimension (p=0.002) than class II subjects; It is possible to conclude that there are facial characteristics transverse and vertical that can be related with the sagittal position of the maxillo-mandibular structures.

3-D airway analysis related to facial morphology / Análisis 3-D de la vía aerea relacionado con la morfología facial

The aim of this investigation was to define the volume and area of the airway in subjects with Class II and Class III skeletal deformity. A cross-sectional study was designed including subjects with facial deformity defined by Steiner's analysis in subjects with indication of orthognathic surgery who presented diagnosis by cone beam computerised tomography. We determined the measurements of maximum area, minimum area and volume of the airway. The data were compared using Spearman's test, with statistical significance defined as p<0.05. 115 subjects were included: 61.7 % Class II and 38.3 % Class III, mean age 27.8 years (± 11.6). A significant difference was observed in the area and volume measurements in the groups studied, with significantly smaller measurements found in Class II (p=0.034). The minimum area was 10.4 mm2 smaller in Class II patients than in Class III, while the general volume of the airway was 4.1 mm3 smaller in Class II than in Class III. We may conclude that Class II subjects present a smaller airway volume than Class III subjects.

El objetivo de esta investigación de definir el volumen y área de vía aérea en sujetos con deformidad esqueletal clase II y III. Se diseñó un estudio de corte transversal incluyendo sujetos con deformidad facial definida según análisis de Stainer en sujetos con indicación de cirugía ortognática que presentaran una tomografía computadorizada de haz cónico como elemento diagnóstico; en este examen se determinaron medidas de área mayor, menor de vía aérea y volumen presente; los datos fueron comparados utilizando pruebas estadísticas con el test de spearman considerando el valor de p<0,05 para definir significancia estadística. 115 sujetos fueron incluidos, siendo 61,7 % de tipo clase II y 38,3 % de sujetos clase III, con una edad promedio de 27,8 años (± 11,6). Se observó una diferencia significativa en mediciones de area y volumen en los grupos estudiados, siendo el grupo de clase II significativamente menor (p=0,034). El área de menor tamaño fue 10,4 mm2 en pacientes clase II que en pacientes clase III, mientras que el volumen general de la vía área fue 4,1 menor en los clase II que en los clase III. Es posible concluir que los sujetos de clase II presentan menor volumen de vía área que los sujetos clase III.