Structural changes of the temporomandibular joint in adolescents with skeletal class III malocclusions after maxillary protraction: An X-ray measurement analysis
10.3969/j.issn.2095-4344.3046
- Author:
Ya Fei LIU
1
Author Information
1. Department of Orthodontics, First Hospital of Hebei Medical University
- Publication Type:Journal Article
- Keywords:
Adolescents;
Bone;
Class III;
Condyle;
Malocclusion;
Maxillary protraction;
Temporomandibular joint;
X-ray
- From:
Chinese Journal of Tissue Engineering Research
2021;25(8):1154-1159
- CountryChina
- Language:Chinese
-
Abstract:
BACKGROUND: For skeletal Class III malocclusions, the positional relationship between the upper and lower jaws and abnormal occlusion can impact the shape of the condyle and the glenoid fossa, as well as the movement of the mandible and the function of the masticatory muscles. Maxillary protraction appliances are one of the effective methods for the treatment of skeletal Class III malocclusion in adolescents, which can reconstruct the positional relationship of the jaws and improve the glenoid fossa-disc-protrusion relationship in patients with skeletal Class III malocclusion. OBJECTIVE: To evaluate the temporomandibular joint changes in adolescents with skeletal Class III malocclusions treated with maxillary protraction. METHODS: Twenty-nine patients (11 girls and 18 boys; age range from 12-14, with a mean age of (12.90±0.99) years were treated with maxillary protraction. Lateral cephalograms were taken before and after treatment. A coordinate system was set to quantitatively analyze the changes of temporomandibular joint fossa, condyle and temporomandibular joint spaces in sagittal and vertical directions. RESULTS AND CONCLUSION: After maxillary protraction, no displacement of the gleniod fossa and the condyle in the sagittal direction was observed (P > 0.05). Simultaneously, in the vertical direction, there was no significant displacement of the gleniod fossa as well as no posterior and superior condyle displacement (P > 0.05). However, the anterior condyle moved upward (P < 0.05). No significant changes in the anterior, superior and posterior space of the temporomandibular joint were observed (P > 0.05). These findings indicate that maxillary protraction treatment can adaptively remodel the temporomandibular joint in adolescents with skeletal Class III malocclusion will undergo adaptive remodeling, but will not adversely affect the function of the temporomandibular joint due to the unchanged joint space.
