Mandibular condyle position in maximum mouth opening: a magnetic resonance imaging evaluation / Posición condilar en apertura oral máxima: una evaluación con imágenes de resonancia magnética

The purpose of this study was to analyze the condylar position in the maximum mouth opening in a group of individuals with and without temporomandibular joint disorders (TMD) using corrected magnetic resonance imaging (MRI). It was analyzed the MRIs of 200 temporomandibular joint (TMJ) of 100 adults (25 males and 75 females). The images protocol of the MRIs were in corrected sagittal plane T1, with the patient kept at a maximum mouth opening without pain. All the images were obtained parallel to the Frankfurt plane. The images were split by two lines parallel to the upper base of the image which was obtained parallel to the Frankfurt plane, tangential to the articular tubercle and the condyle of each TMJ, and set along the discrepancy of the condylar position on both sides and the position with regard to the articular tubercle. The discrepancy was 45 percent overall, the most common condylar position types were 5 and 6 on the right and left sides in both the male and female TMJ patients. In this regard, the highest mean values were found for the maximum mouth opening. Our results support the hypothesis that the condylar position is not directly related to the magnitude of the oral opening.

El propósito de este estudio fue analizar mediante resonancia nuclear magnética (RNM) la posición condilar en apertura máxima en pacientes sin alteraciones de la articulación temporomandibular (ATM). Se utilizaron 200 imágenes de 100 individuos adultos (25 hombres y 75 mujeres) observadas en plano sagital corregido en T1 con el paciente en apertura máxima sin dolor, la región de la ATM se dividió mediante dos líneas perpendiculares entre sí, tangentes a la cabeza mandibular y al tubérculo articular y se estableció la discrepancia de la posición condilar en ambos lados y la posición condilar con respecto al tubérculo articular. La discrepancia general fue del 45 por ciento, las posiciones condilares más frecuentes fueron los tipos 5 y 6 en los lados derecho e izquierdo en ATM de hombres y de mujeres, en esta relación se encontraron los mayores valores medios de apertura oral máxima. Nuestros resultados apoyan la hipótesis que la posición condilar no se encuentra en relación directa con la magnitud de la apertura oral.

A cephalometric study on the relationship between mandibular opening movement and morphology of craniofacial skeleton / 대한치과교정학회지

Lateral cephalometric X-ray films in maximal intercuspation and maximal opening of 68 children were taken and analyzed to examine the pattern of condylar movement and to study the relationship between opening movement and morphologic factors of craniofacial skeleton. The results were as follows : 1. The mean value of maximal opening capacity was 47.1mm, condylar moving distance was 18.1mm, horizontal condyle movement was 17.5mm, vertical condyle movement was 3.8 mm and condylar moving angle was 13.1degrees. 2. The maximal opening capacity had positive relationship with the length of anterior cranial base, mandible and maxillary complex and with posterior facial height and had negative relationship with articular angle, sagittal jaw relationship. 3. Vertical condyle movement and condylar moving angle had positive relationship with articular angle and had negative relationship with gonial angle. 4. Horizontal condyle movement and condylar moving distance had positive relationship with the length of maxillary complex.