Pneumatization of the temporal portion of the zygomatic arch: The contribution of computed tomography to the reconstruction in volumetric two‑dimensional and three‑dimensional, with the aid of image rendering protocols.

Pneumatization refers to the asymptomatic development of cavities containing air within them. There is great variability in the extent of temporal bone pneumatization. Nevertheless, in a few cases it extends to the zygomatic process. Images are presented in which the panoramic radiograph and hypocycloidal tomography reveal this variation from the norm, to which professionals must be alert, since the images may simulate the presence of pathology. In this case report we describe the presence of pneumatization of the petrous and zygomatic portions of the temporal bone, demonstrating the contribution of CT to reconstruction in volumetric 2D and 3D, with the aid of image rendering protocols.

Cephalometric evaluation of condyle‑fossa position in dentulous and edentulous subjects.

Context: Whenever there is loss of teeth and occlusion, it triggers a change in the functional and structural relationship of the mandible. Various physiologic factor such as age and changes in occlusion lead to specific remodeling changes in the temporomandibular joint (TMJ). Aims: The aim of this study was to evaluate and compare the influence of dentition on condyle‑fossa position by comparing this variable in dentulous and edentulous subjects using lateral cephalogram. Settings and Design: The study was conducted on 25 dentulous and 25 edentulous subjects, comprising of males and females, visiting Yenepoya University, Mangalore. Subjects and Methods: The age ranges of dentulous subjects were 25–30 years and edentulous subjects of 45–65 years with 1–5 years of edentulousness were chosen. Lateral cephalograms were taken, and various reference lines and planes were used to determine the center of condyle and center of the glenoid fossa. Statistical Analysis Used: The results were analyzed by SPSS version 7.0 (SPSS Inc., Chicago) and statistical analysis used was t‑test. Results: Condyle was placed upward and forward, and glenoid fossa was situated more anteriorly in edentulous subjects compared to dentulous subjects. Conclusions: This study supports the concept that TMJ is an articular triad with two points of contact provided by TMJ and third contact by the dentition. Alteration in any one of these contact points will produce secondary morphological changes in other two points.

Tope precondíleo, una alternativa quirúrgica para el tratamiento de la luxación crónica mandibular. Modificación a la técnica de Norman. Experiencia en 12 pacientes / Pre-condylar stop: surgical alternative for the treatment of mandibular chronic luxation. Modification of Norman Technique. Experience with 12 patients

Propósito: Este artículo describe el uso del injerto de mentón para el aumento de la eminencia articular, como tratamiento para la luxación crónica mandibular. Pacientes y métodos: El presente estudio se llevó a cabo en 12 pacientes, con una edad promedio de 44 años a quienes se les diagnosticó luxación crónica mandibular, con sintomatología dolorosa mayor o igual a 8 en la escala visual análoga (EVA), evolución de 1.5 años en promedio, y una apertura bucal de 55 mm o mayor a ésta, tratados en forma conservadora durante por lo menos tres meses sin presentar mejoría. Dichos pacientes fueron tratados con una modificación a la técnica de Norman donde se les realiza aumento de la eminencia articular mediante la colocación de un injerto de mentón, a través de un abordaje preauricular. Resultados: En ninguno de los casos se presentaron nuevos eventos de luxación durante los 18 meses posteriores a la cirugía. Conclusiones: Se demostró que la corrección de la luxación crónica mandibular, mediante colocación de tope precondíleo con injerto de mentón es una técnica eficaz y segura.

Aim: The aim of the present article was to describe use of chin bone graft to increase articular eminence as preferred treatment for mandibular chronic luxation. Patients and methods: The present study was undertaken with 12 patients, average age 44 years. Patients had been diagnosed as suffering from chronic mandibular luxation (dislocation), with pain symptomatology rating 8 or more in the Analogous Visual Scale (AVS). Patients had experienced an average 1.5 year evolution and 55 mm or more oral opening. Patients had been conservatively treated for at least three months, with no visible improvement. Patients were then treated following a modified Norman technique, in which an articular eminence augmentation is performed with a chin bone graft placed through pre-auricular approach. Results: None of the patients presented new dislocation events during the 18 month follow up period after surgery. Conclusions: The present study showed the fact that mandibular chronic dislocation correction with placement of pre-condylar stop with chin bone graft is an effective and safe technique.

Evaluation of articular eminence morphology and inclination in TMJ internal derangement patients with MRI / Evaluación de la morfología e inclinación de la eminencia articular en pacientes con trastorno interno de ATM con MRI

Articular eminence morphology and inclination are reported to be two predisposing factors for the internal derangement (ID). The purpose of this study is to investigate the relationship between the inclination and morphology of the articular eminence and ID. The study included 70 temporomandibular joints with ID in 35 patients: 51 joints had disc displacements with reduction (DDWR) and 19 joints had disc displacements without reduction (DDWOR). All subjects underwent bilateral high resolution magnetic resonance imaging scans which were performed in the sagittal and coronal planes with mouths closed and opened. Articular eminence morphology was characterized as box, sigmoid, flattened, or deformed. Articular eminence inclination was measured at three positions: steep (from 60° to 90°), moderate (from 30° to 60°) and shallow (from 15° to 30°). The images were divided into two; DDWR and DDWOR, and these two criteria were compared. The images of the two groups were compared; while flattened form was occurred with the highest incidence in the DDWOR group, sigmoid form was the most frequent in the DDWR group and articular eminence inclination was found steeper than it was for the DDWOR group. The steepness of the articular eminence may not have a predisposing effect on the development of disc displacements.

La morfología e inclinación de la eminencia articular son reportados como dos factores predisponentes para el trastorno interno (TI). El propósito de este estudio fue investigar la relación entre la inclinación y la morfología de la eminencia articular y el TI. El estudio incluyó a 70 articulaciones temporomandibulares, con TI en 35 pacientes: 51 articulaciones con desplazamiento discal con reducción (DDCR) y 19 de las articulaciones tuvieron desplazamiento discal sin reducción (DDSR). Todos los sujetos fueron sometidos a imágenes de resonancia magnética bilaterales de alta resolución que se realizaron en los planos sagital y coronal con la boca cerrada y abierta. La morfología articular la eminencia se caracterizó como una caja, sigmoide, aplanada, o deforme. La inclinación de la eminencia articular se midió en tres posiciones: empinada (de 60 ° a 90 °), moderada (entre 30 ° a 60 °) y poco profunda (entre 15 ° y 30 °). Las imágenes fueron divididos en dos; DDCR y DDSOR, y estos criterios fueron comparados. Al comparar las imágenes de ambos grupos, la forma aplanada se observó con mayor incidencia en el grupo de DDSR, la forma sigmoide fue la más frecuente en el grupo de DDCR y la inclinación de la eminencia articular se encontró más pronunciada que en el grupo DDSR. La inclinación de la eminencia articular puede no tener un efecto predisponente en el desarrollo de los desplazamientos de disco.

A comparative study to evaluate the discrepancy in condylar guidance values between two commercially available arcon and non-arcon articulators: A clinical study.

Aim: The purpose of this study was comparative evaluation of sagittal condylar values of arcon and non-arcon articulators with cephalometric readings and to determine the amount of discrepancy in sagittal condylar guidance values between arcon and non-arcon articulators using same protrusive record. Materials and Methods: Twenty subjects in the age group of 19-35 years, free from temporomandibular joint dysfunction, and occlusal disharmony, with healthy dentition participated in the study. Hanau H2 (non-arcon type) and Hanau Wide-Vue (arcon type) articulators were programmed for sagittal condylar guidance values using the same protrusive record made in polysiloxane bite registration material with edge to edge degree of protrusion. The resultant values for both the articulators on either side were compared with values obtained from tracing of digital lateral cephalogram using Kodak Dental imaging Window software 6.6.3.0-C program. The tabulated data were subjected to statistical analysis, ANOVA (Fishers 'F' test) for group comparison, Tukey's HSD test for inter-comparison, student's unpaired 't' test for intra-group comparison, and level of significance (P) was calculated using the same. Results: The mean sagittal condylar guidance values of the three different groups were found to be very highly significant (P=0.001) and highly significant (P=0.002) on the right and left sides respectively. There was a very highly significant difference (P=0.001) and highly significant difference (P=0.003) between the arcon and non-arcon group on the right and left side respectively. No significant difference was found between the arcon and cephalometric group (P=0.284 right, P=0.853 left) and a statistically significant difference was found between the non-arcon and cephalometric group (P=0.049 right, P=0.015 left). On intragroup comparison there was no statistically significant difference in sagittal condylar values on the right and left sides. Conclusion: The mean difference in the sagittal condylar guidance values obtained from non-arcon and arcon articulators shows a low level of reproducibility, and no significant difference found in mean sagittal condylar values obtained from arcon articulator and cephalometric tracings indicates replication of sagittal condylar guidance value from image of articular eminence.

Changes in height and inclination of the articular eminence during the growth period / 대한치과교정학회지

OBJECTIVE: The purpose of this study was to assess the changes in height and inclination of the articular eminence during the growth period. METHODS: One hundred and sixty subjects (71 males and 89 females) with a normal skeletal pattern and TMJ function, ranging in age from 5.9 to 19.7 years were divided according to their chronological age into six groups. Lateral individualized corrected TMJ tomograms were taken of all subjects, and the height and inclination of the articular eminence were measured. UNIANOVA was used to compare the differences between the age groups. Mann-Whitney test was used to compare the differences between male and female subjects. RESULTS: The height and the inclination of the articular eminence were increased and became steeper with age, and the height and the inclination were larger in male than in female subjects. CONCLUSIONS: Dynamic changes in the height and the inclination of the articular eminence were observed during the growth period, therefore a full understanding of the growth of the articular eminence is important for orthodontic and orthopedic treatment in this period.

Locked-jaw as a Result of an Unexpected Anatomic Variation of the Temporomandibular Joint: A case report / 대한마취과학회지

A 36-year-old woman with an unremarkable medical history presented for laparoscopic cholecystectomy. Routine preoperative assessment of the patient's airway revealed normal jaw opening. Upon induction of anesthesia, her jaw locked in a nearly closed position. X-ray and MRI of the temporomandibular joints that were taken postoperatively showed normal findings except for the steeper posterior angles of the articular eminences. During the next induction of anesthesia, intubation was readily accomplished by opening the mandible with a forward pulling of the chin.

A study on the size of condyle and the posterior slope of the articular eminence in patients with temporomandibular joint disorders

0.05). 3. There were no statistically significant differences in the condylar ratio between the groups (p>0.05). 4. There were no statistically significant differences in the discrepancies of the left and right ramus length measurements between the groups (p>0.05). 5. The relative size of condyle to fossa in the group of temporomandibular disorders was smaller than that in the normal group (p<0.05).