Mandibular and temporomandibular morphologic characteristics of patients with suspected unilateral condylar hyperplasia: a CT study.

INTRODUCTION: Facial asymmetry associated with unilateral condylar hyperplasia (UCH) is a complicated clinical condition. OBJECTIVE: The objective of this study was to describe morphological characteristics of the mandible and the temporomandibular joint in patients with facial asymmetry, using computed tomography and 3D reconstruction. METHODS: A retrospective observational study was performed with patients displaying facial asymmetry evaluated by single photon emission computed tomography (SPECT)/CT analysis, for suspected UCH, between 2015 and 2018. The following variables were compared between the affected side (producing the asymmetry) and the contralateral side (side to where the jaw is deflected): condylar length, condylar medial and lateral pole length, mandibular ramus length, intra-articular spaces, articular eminence height and position of the posterior wall of the glenoid fossa. RESULTS: Forty-three patients (21 women, mean age: 20.7 ± 7.25 years) with facial asymmetry were included, 19 patients presented right side deviation and 24 patients had left side deviation. Condylar length, lateral pole length, the sum of maximum values and articular eminence height were greater in the affected side (p< 0.05). A positive correlation was found between the position of the posterior wall of the glenoid fossa and the articular eminence height in the affected side (r = 0.442). CONCLUSIONS: In patients with suspected UCH, evaluated through CT, craniofacial measurements showed significantly larger condylar length and the condylar sum of maximum values in the affected side. A positive correlation was found between the increased dimensions of the articular eminence and the more posterior position of the glenoid fossa in the affected side.

Mandibular and temporomandibular morphologic characteristics of patients with suspected unilateral condylar hyperplasia: a CT study

ABSTRACT Introduction: Facial asymmetry associated with unilateral condylar hyperplasia (UCH) is a complicated clinical condition. Objective: The objective of this study was to describe morphological characteristics of the mandible and the temporomandibular joint in patients with facial asymmetry, using computed tomography and 3D reconstruction. Methods: A retrospective observational study was performed with patients displaying facial asymmetry evaluated by single photon emission computed tomography (SPECT)/CT analysis, for suspected UCH, between 2015 and 2018. The following variables were compared between the affected side (producing the asymmetry) and the contralateral side (side to where the jaw is deflected): condylar length, condylar medial and lateral pole length, mandibular ramus length, intra-articular spaces, articular eminence height and position of the posterior wall of the glenoid fossa. Results: Forty-three patients (21 women, mean age: 20.7 ± 7.25 years) with facial asymmetry were included, 19 patients presented right side deviation and 24 patients had left side deviation. Condylar length, lateral pole length, the sum of maximum values and articular eminence height were greater in the affected side (p< 0.05). A positive correlation was found between the position of the posterior wall of the glenoid fossa and the articular eminence height in the affected side (r = 0.442). Conclusions: In patients with suspected UCH, evaluated through CT, craniofacial measurements showed significantly larger condylar length and the condylar sum of maximum values in the affected side. A positive correlation was found between the increased dimensions of the articular eminence and the more posterior position of the glenoid fossa in the affected side.

RESUMO Introdução: A assimetria facial associada à hiperplasia condilar unilateral (HCU) é uma condição clínica complexa. Objetivo: O objetivo desse estudo foi descrever as características morfológicas da mandíbula e da articulação temporomandibular de pacientes com assimetria facial, usando tomografia computadorizada e reconstruções tridimensionais. Métodos: Esse estudo observacional retrospectivo foi realizado em pacientes com assimetria facial e suspeita de HCU, avaliados por meio da análise de tomografia computadorizada de emissão de fóton único (SPECT)/TC, entre os anos de 2015 e 2018. As seguintes variáveis foram comparadas entre o lado afetado (responsável pela assimetria) e o lado contralateral (lado para onde a arcada estava desviada): comprimento condilar, comprimento dos polos medial e lateral do côndilo, comprimento do ramo mandibular, espaços intra-articulares, altura da eminência articular e posição da parede posterior da fossa glenoide. Resultados: A amostra constituiu-se de 43 pacientes (21 mulheres, idade média: 20,7 ? 7,25 anos) com assimetria facial, da qual 19 pacientes apresentavam desvio do lado direito e 24, do lado esquerdo. O comprimento condilar, o comprimento do polo lateral, a soma dos valores máximos e a altura da eminência articular foram maiores no lado afetado (p< 0,05). Foi encontrada uma correlação positiva entre a posição da parede posterior da fossa glenoide e a altura da eminência articular no lado afetado (r = 0,442). Conclusão: Em pacientes com suspeita de HCU, avaliados por meio de TC, as medidas craniofaciais mostraram um comprimento condilar e a soma dos valores condilares máximos significativamente maiores no lado afetado. Foi encontrada uma correlação positiva entre as dimensões aumentadas da eminência articular e a posição mais posterior da fossa glenoide no lado afetado.

Are There Mandibular Morphological Differences in the Various Facial Asymmetry Etiologies? A Tomographic Three-Dimensional Reconstruction Study.

PURPOSE: Facial asymmetries (FAs) have been classified according to the mandibular morphological differences to obtain better diagnostic and treatment decisions. The purpose of the present study was to establish diagnostic differentiation among FAs using computed tomography (CT) and 3-dimensional (3D) reconstruction. MATERIALS AND METHODS: We performed a cross-sectional study of patients with a diagnosis of FA, who had been evaluated by CT and 3D reconstruction in the same clinical center from 2015 to 2018. The following mandibular anatomic characteristics were compared between the 2 sides (deviated side vs contralateral side) and type of FA: condylar length, mandibular ramus length and width, mandibular body length, and symphysis deviation. RESULTS: The 53 patients included 23 men and 30 women (age range, 16 to 25 years). Six categories of FA were identified: hemimandibular elongation (n = 25), hemimandibular hyperplasia (n = 2), hybrid hyperplasia (n = 3), asymmetric mandibular prognathism (n = 14), asymmetry of the glenoid fossa (n = 2), and functional laterognathism (n = 7). The condylar length and mandibular ramus width were greater in the displaced side than in the contralateral side, with differences of -2.0 ± 2.8 mm (P < .001) and -0.5 ± 1.7 mm (P = .009), respectively. The mandibular body length was greater on the contralateral side (mean difference, 2.1 ± 3.5 mm; P < .001). The symphysis deviation was 5.0 ± 3.4 mm, and those with a hybrid form presented with a greater deviation, with values greater than 10 mm, followed by those with hemimandibular elongation. CONCLUSIONS: The evaluation of the CT images and 3D reconstructions in patients with FA provided detailed information of the mandibular structure that is useful to compare the differences between sides and to classify the entities associated with FA.