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.

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

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

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

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.

Changes in the Craniomaxillofacial Growth and Development of Sprague Dawley Rats Subjected to Permanent Experimental Unilateral Nasal Obstruction / Cambios en el Crecimiento y Desarrollo Cráneo Maxilo Facial de Ratas Sprague Dawley Sometidas a Obstrucción Nasal Unilateral Experimental Permanente

SUMMARY: Breathing is considered a vital function dependent on factors such as adequate permeability of the nasal route, which is linked to physiological functions, intellectual processes, and craniofacial growth. The aim of this study was to determine the changes in the craniomaxillofacial growth and bone development of Sprague Dawley rats subjected to permanent experimental unilateral nasal obstruction. Twenty-four newborn rats were used, randomized, and divided into experimental and control groups. The right nostril was obstructed, and weight, length, and Lee's index measurements were recorded at 8 and 16 weeks. Craniomandibular x-rays were taken of each animal, obtaining linear neuro- and viscerocranial measurements. Then, a biochemical analysis was performed to measure the alkaline phosphatase concentration. The results were analyzed in the SPSS software, performing a descriptive analysis, using a t-test for independent samples, comparing basal, cephalometric, and biochemical characteristics between the control and experimental groups, considering a significance range of 5%. When comparing the experimental and control groups, the variables length, weight, and Lee's index presented no significant differences. In the x-ray analysis, at 8 weeks, the Co-L1 and Co-Mn measurements were reduced, whereas the Ba-So increased, with significant differences. At 16 weeks, the L1-O, Po-Ba, and E-Mu measurements decreased; however, Co-Gn registered a greater value with significant differences. The alkaline phosphatase levels fell significantly at week 16 in the experimental group. In conclusion, the reduction of permanent nasal respiratory flow is related to modifications in facial growth at 8 and 16 weeks and to the reduction of alkaline phosphatases at 16 weeks.

La respiración se considera una función vital, dependiente de factores como la permeabilidad adecuada de la vía nasal, vinculada con funciones fisiológicas, procesos intelectuales y crecimiento cráneofacial. El objetivo de este estudio fue determinar los cambios en el crecimiento y desarrollo óseo cráneo maxilo facial de ratas Sprague Dawley sometidas a obstrucción nasal unilateral experimental permanente. Se utilizaron 24 ratas macho neonatas, randomizadas y divididas en grupo control y experimental. Fue realizada obstrucción nasal de la narina derecha y realizadas mediciones de peso, longitud e índice de Lee a las 8 y 16 semanas. Se efectuaron radiografías cráneomandibulares a cada animal, obteniendo medidas lineales de neuro y viscerocráneo. Posteriormente se realizó análisis bioquímico, para medir la concentración de fosfatasa alcalina. Los resultados fueron analizados en el software SPSS, realizándose análisis descriptivo, empleando prueba T para muestras independientes comparando características basales, cefalométricas y bioquímicas entre los grupos control y experimental, considerando un umbral de significancia de 5 %. Al comparar los grupos control y experimental, las variables longitud, peso e índice de Lee no presentaron diferencias significativas. En el análisis radiográfico, a las 8 semanas, las medidas Co-L1 y Co-Mn presentaron reducción, mientras que Ba-So aumentó, con diferencias significativas. A las 16 semanas, las medidas L1-O, Po-Ba y E-Mu disminuyeron, sin embargo, Co-Gn registró un mayor valor, con diferencias significativas. Los niveles de fosfatasa alcalina disminuyeron significativamente en la semana 16 en el grupo experimental. En conclusión, la reducción de flujo respiratorio nasal permanente se relaciona con modificaciones del crecimiento facial a las 8 y 16 semanas y con la reducción de ALK en análisis a las 16 semanas.

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.

The Use of Human Amniotic Membrane (hAM) as a Treatment Strategy of Medication-Related Osteonecrosis of the Jaw (MRONJ): A Systematic Review and Meta-Analysis of the Literature.

Background and objectives: Although it is very uncommon, medication-induced osteonecrosis of the jaw (also known as MRONJ) can have serious consequences. Traditionally, this adverse event has been recognised in patients who were treated with bisphosphonate (BP) drugs. Nevertheless, in recent years, it has been established that individuals having treatment with various types of medications, such as a receptor activator of nuclear factor kappa-Β ligand inhibitor (denosumab) and antiangiogenic agents, have had the same issue. The purpose of this research is to determine if the application of human amniotic membrane (hAM) may be used as a therapy for MRONJ. Material and Methods: A multi-source database (MEDLINE, EMBASE, AMED, and CENTRAL) systematic search was performed. The major objective of this study is to obtain an understanding of the efficacy of hAM when it is employed as a treatment modality for MRONJ. The protocol of this review was registered in the INPLASY register under the number NPLASY202330010. Results: The authors were able to include a total of five studies for the quality analysis, whereas for the quantity evaluation, only four studies were eligible. A total of 91 patients were considered for the investigation. After treatment with human amniotic membrane (hAM), a recurrence of osteonecrosis was observed in n = 6 cases (8.8%). The combined efficacy of surgical therapy and the use of hAM resulted in an overall success rate of 91.2%. Intraoperative complications were only documented in one article, and they were mostly caused by the positioning of the hAM, which led to wound breakdown at the surgical site. Conclusions: Based on the small amount of data and low-quality research included in this study, using human amniotic membranes to treat MRONJ might represent a feasible option. Nevertheless, further studies with a wider patient population are required to understand the long-term impacts.

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.

Medication-Related Osteonecrosis of the Jaws (MRONJ) in Children and Young Patients-A Systematic Review.

Medication-related osteonecrosis of the jaw (MRONJ) is defined by the American Association of Oral and Maxillofacial Surgeons (AAOMS) as the presence of an exposed bone area in the maxillofacial region, present for more than eight weeks in patients treated with the use of antiresorptive or antiangiogenic agents, with no history of radiation or metastatic disease. Bisphosphonates (BF) and denosumab (DS) are widely used in adults for the management of patients with cancer and osteoporosis, and recently there has been an increase in their use in child and young patients for the management of disorders such as osteogenesis imperfecta (OI), glucocorticoid-induced osteoporosis, McCune-Albright syndrome (MAS), malignant hypercalcemia, and others. There are differences between case reports in adults compared to child and young patients related to the use of antiresorptive/antiangiogenic drugs and the development of MRONJ. The aim was to analyze the presence of MRONJ in children and young patients, and the relation with oral surgery. A systematic review, following the PRISMA search matrix based on the PICO question, was conducted in PubMed, Embase, ScienceDirect, Cochrane, Google Scholar, and manual search in high-impact journals between 1960 and 2022, publications in English or Spanish, including randomized and non-randomized clinical trials, prospective and retrospective cohort studies, cases and controls studies, and series and case reports. A total of 2792 articles were identified and 29 were included; all of them published between 2007 and 2022, identifying 1192 patients, 39.68% male and 36.24% female, aged 11.56 years old on average, using these drugs mainly for OI (60.15%); 4.21 years on average was the therapy time and 10.18 drug doses administered on average; oral surgery was observed in 216 subjects, reporting 14 cases of MRONJ. We concluded that there is a low presence of MRONJ in the child and youth population treated with antiresorptive drugs. Data collection is weak, and details of therapy are not clear in some cases. Deficiencies in protocols and pharmacological characterization were observed in most of the included articles.

Diagnosis and Treatment in Unilateral Condylar Hyperplasia.

Unilateral condylar hyperplasia (UCH) is an uncommon disease involving progressive facial asymmetry. The aim of this research was to perform an analysis of the diagnosis and treatment of patients with UCH in a clinical series. An observational retrospective study was performed on subjects with progressive facial asymmetry in the lower third of the face; all the subjects were under treatment with condylectomy and orthodontics to improve occlusion and face balance. Variables such as age, sex, clinical type, SPECT (single photon emission computed tomography) intensity and a requirement for secondary surgery were included; the Shapiro Wilk test was performed to analyze the normality of the data and nonparametric analysis and the Kruskal-Wallis or Mann-Whitney tests were used to assess the association between the SPECT difference and the variables, where 2-tailed p values < 0.05 were considered to be statistically significant. Forty-nine patients between 10 and 45 y.o. (average age: 19.1 ± 7.4 y.o.) were included in the study. There were 41 female (83.6%) and 8 male (16.4%) subjects. The SPECT analysis comparing the right and left condyles with more than 10% in caption of the isotope was present in 46 subjects; the results obtained using SPECT were not statistically related to the age or sex of the sample (p = 0.277). The patients were classified into clinical types I, II and III, and no correlations could be confirmed between the clinical type and other variables. High condylectomy was conducted on all patients, among which 14 patients underwent a secondary surgery for orthognathic or cosmetic treatment, and was not related to the initial variables used in diagnosis (p = 0.98); interestingly, the second surgical treatment was more present in the clinical type I and in subjects under 16 years old with no statistical differences. Clinical analysis, medical records, 3D imaging and SPECT should be used as a complementary analysis in assessing the diagnosis of UCH and progressive facial asymmetry.

The use of zygomatic implants in severe maxillary atrophy: a systematic and meta-analysis review of randomised clinical trials / El uso de implantes zigomáticos para atrofia maxilar severa: una revisión sistemática y meta-análisis de ensayos clínicos aleatorizados

SUMMARY: Conventional implant treatment cannot always be used to rehabilitate edentulous patients with advanced maxillary atrophic. Zygomatic dental implants have been used over the past 20 years as an alternative treatment solution to bone grafting. The purpose of this meta-analysis is to evaluate the implant and prosthetic survival rate in non-oncologic patients with a severely atrophic maxilla. This review also aims to better understand the rate of peri-operative complications in this cohort of patients. A multi-database (PubMed, MEDLINE, EMBASE, and CINAHAL) focused systematic search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations. Any randomised control trials studies involving human participants treated with zygomatic osseous implants were included. After eliminating duplicates, a total of 4 studies met the inclusion criteria for this meta-analysis review. With all the studies included there was a total of 174 patients treated with zygomatic osseous implants. The overall implant success rate was 98.03 %. The prosthetic success rate was 96.4 %. The most frequent peri-operative complication was sinusitis. Based on the limited data available in literature, zygomatic dental implants represent a valid alternative to bone augmenting procedure. However, they are not without risks and longer follow-ups are required to confirm the validity of the treatment in long term.

Los tratamientos convencionales con implantes no siempre pueden ser usados para rehabilitar pacientes edentulos con atrofia maxilar avanzada. Los implantes dentales zigomáticos son usados por los pasados 20 años como alternativa de tratamiento a las reconstrucciones óseas. El objetivo de este meta-análisis es evaluar la sobrevida de implantes y prótesis en pacientes no oncológicos con maxila severamente atrófica. Esta revisión también pretende entender al promedio de complicaciones peri operatorias en esta cohorte de pacientes. Una búsqueda sistemática en bases de datos múltiples (PubMed, MEDLINE, EMBASE y CINAHAL) fue desarrollada de acuerdo a recomendaciones de Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Cualquier estudio clínico aleatorizado de participantes humanos donde se utilizaron los implantes zigomáticos fueron incluidos. Después de eliminar duplicados, un total de 4 estudios cumplieron los criterios de inclusión para esta meta análisis. Con todos los estudios incluidos se obtuvieron 174 pacientes tratados con implantes zigomáticos. El promedio de éxito fue de 98,03 %. El promedio de éxito de la rehabilitación fue de 96,4 %. La complicación mas frecuente fue la sinusitis. Basados en los datos limitados en la literatura, los implantes zigomáticos representan una alternativa valida a los procedimientos de aumento óseo. Sin embargo, estos no están libres de riesgos y seguimientos de mayores periodos son necesarios para confirmar la validez de los tratamientos en el largo plazo.

Central Giant Cell Granuloma in the Mandibular Condyle in a Teenager. A Case Report with Literature Review.

Central giant cell granulomas (CGCG) are not common in the mandibular condyle. In teenagers, the problem is more complex because of difficulties in diagnosis and treatment involving the potential growth of the mandibular process and development of the face. In this short communication a case is presented of an eleven-year-old female under diagnosis of central giant cell granuloma affecting the mandibular condyle treated surgically in two steps using a condylectomy and vertical ramus osteotomy at the first time and later orthognathic surgery, showing the clinical evolution after 13 years of follow-up. In addition, we performed a review of the scientific reports related to CGCG in the mandibular condyle to compare this treatment with others, in terms of follow-up and results. We concluded that the CGCG affecting the mandibular head can be properly treated with low condilectomy, vertical mandibular ramus sliding osteotomy, and discopexy.

TMJ Position in Symmetric Dentofacial Deformity.

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

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

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

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

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.

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.

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.

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.

2D and 3D imaging for morphological assessment of maxillofacial cyst and tumors: a case series / Imagen 3D para la evaluación morfológica de quistes y tumores maxilofaciales: serie de casos

SUMMARY: The use and importance of cone beam computed tomography (CBCT) in the diagnostic, treatment and long term follow up of odontogenic tumours, as well as one reconstruction and dental implants rehabilitation is reported. This clinical series shows diagnosis of odontogenic tumors using selected and used CBCT for initial diagnosis, morphological characterization, and follow up for 5 to 10 years. The CBCTs showed the size and form of the tumor and the follow up showed a satisfactory remodelling of bone and the success in the rehabilition with dental implants. No signs of recurrence were observed. The conventional radiographies, Fan Beam CT, Cone Beam CT and Magnetic Resonance Imaging (MRI) are discussed in the use for follow up of odontogenic tumors. It is concluded that CBCT is an efficient tool for diagnosis, follow up and assessment of the morphology and size of the tumor in order to achieve the best treatment plan, returning the functional conditions to the patients.

RESUMEN: Se reporta el uso y la importancia de la tomografía computarizada de haz cónico (CBCT) en el diagnóstico, tratamiento y seguimiento a largo plazo de tumores odontogénicos, tal como en una reconstrucción y rehabilitación de implantes dentales. Esta serie clínica muestra el diagnóstico de tumores odontogénicos utilizando CBCT seleccionados y usados para el diagnóstico inicial, caracterización morfológica y seguimiento durante 5 a 10 años. Los CBCT mostraron el tamaño y la forma del tumor y el seguimiento mostró un remodelamiento óseo satisfactorio y el éxito de la rehabilitación con implantes dentales. No se observaron signos de recurrencia. Las radiografías convencionales, el uso de TAC, TAC de haz cónico y resonancia magnética nuclear (RMN) se consideran para el seguimiento de tumores odontogénicos. Se concluye que CBCT es una herramienta eficaz en el diagnóstico y seguimiento a largo plazo para evaluar la morfología del tumor y de su tamaño, y además, para obtener los mejores resultados en el tratamiento y eventuales condiciones funcionales de los pacientes.

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.