Three-dimensional assessment of the temporomandibular joint and mandibular dimensions after early correction of the maxillary arch form in patients with Class II division 1 or division 2 malocclusion

Abstract

ObjectiveThis study aimed to assess three-dimensional changes in the temporomandibular joint positions and mandibular dimensions after correction of dental factors restricting mandibular growth in patients with Class II division 1 or division 2 malocclusion in the pubertal growth period.MethodsThis prospective clinical study included 14 patients each with Class II division 1 (group I) and Class II division 2 (group II) malocclusions. The quad-helix was used for maxillary expansion, while utility arches were used for intrusion (group I) or protrusion and intrusion (group II) of the maxillary incisors. After approximately 2 months of treatment, an adequate maxillary arch width and acceptable maxillary incisor inclination were obtained. The patients were followed for an average of 6 months. Intraoral and extraoral photographs, plaster models, and cone-beam computed tomography (CBCT) images were obtained before and after treatment. Lateral cephalometric and temporomandibular joint measurements were made from the CBCT images.ResultsThe mandibular dimensions increased in both groups, although mandibular positional changes were also found in group II. There were no differences in the condylar position within the mandibular fossa or the condylar dimensions. The mandibular fossa depth and condylar positions were symmetrical at treatment initiation and completion.ConclusionsClass II malocclusion can be partially corrected by achieving an ideal maxillary arch form, particularly in patients with Class II division 2 malocclusion. Restrictions of the mandible in the transverse or sagittal plane do not affect the temporomandibular joint positions in these patients because of the high adaptability of this joint.

Effects of rapid maxillary expansion on temporomandibular joints:

“…In a systematic review about sagittal changes after RME in Class II patients, 31 it was concluded that the studies found had methodological deficiencies with controversial or non-relevant sagittal effects. Coskuner and Ciger (2015) 18 verified that a Class II relationship can be corrected to a certain extent by slow expansion of the maxilla with a quadhelix; however, there was no significant effect on the TMJ.…”

“…Of these, one study was eliminated because it was a protocol proposal to be followed in future studies, 15 one for evaluating pre-and post-intervention changes through gypsum models and bite registration, 16 one for assessing condylar change by means of zonograms, 17 and five studies were excluded since they examined patients who underwent slow maxillary expansion. 10,[18][19][20][21] Therefore, seven articles from the systematic search were included for qualitative analysis; [22][23][24][25][26][27][28] as well as one record found by hand search (n ¼ 1); 29 totaling eight articles included in this review ( Table 1). A quantitative analysis was not feasible given the heterogeneity in the methodology of the selected articles.…”

Relación entre la presencia de cambios óseos de osteoartrosis del cóndilo mandibular e inclinación de la eminencia articular en pacientes clase II esquelética evaluados mediante tomografía computarizada de haz cónico

“…La inclinación de la eminencia articular puede variar entre los individuos y determina la trayectoria de movimiento condíleo, así como el grado de rotación del disco sobre el cóndilo ( [1][2][3][4][5][6][7][8][9][10] ). La profundidad de la cavidad glenoidea varía y el desarrollo de la eminencia articular depende de los estímulos funcionales que tenga el cóndilo ( [11][12][13][14][15][16][17][18][19][20]. Estudios sugieren que la formación ósea de compensación de la cavidad glenoidea podría ayudar a soportar el aumento de las sobrecargas en la ATM que acompañan los cambios óseos degenerativos condilares ( 2,(11)(12)(13)(14)(15) ).…”

“…Una opinión que Rev Cient Odontol (Lima). 2019; 7 (1): [34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52] Víctor Pardo Juárez se respalda por estos estudios es que el desarrollo de la eminencia articular y el cóndilo mandibular se ve más afectado por la función que por las características de la base del cráneo ( [15][16][17][18][19] ).…”

Condylar Movement Assessment is Severe Attrition Patient Undergoing Orthodontic Treatment: Joint Vibrant Analysis Procedure

“…Various techniques are used to assess the condylar position in CBCT images of temporomandibular joints [6,7], emphasizing the sagittal and axial views as the main point. The condylar position obtained in sagittal and axial views are measured with little regard to the coronal view.…”