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Effect of Molar Distalization on Condyle-Glenoid Fossa Relationship
Dani Abo Samra1, Rania Hadad1, Omar Hamadah2
1Department of Orthodontics and Dentofacial Orthopaedics, Faculty of Dental Medicine, Damascus University, Damascus, Syria.
Molar distalization using the distal jet appliance significantly increased superior and posterior temporomandibular joint spaces and vertical facial dimensions. These changes may not be clinically significant.
Area of Science:
- Orthodontics
- Temporomandibular Joint Disorders
- Dental Imaging
Background:
- Orthodontic treatment can affect masticatory structures, particularly the temporomandibular joint (TMJ).
- Limited data exists on the TMJ's response to molar distalization.
Purpose of the Study:
- To investigate condyle-fossa relationship changes after molar distalization using the distal jet appliance.
- To assess the impact of molar distalization on TMJ joint spaces and vertical cephalometric measurements.
Main Methods:
- Cone-beam computed tomography (CBCT) scans of 25 patients before and after molar distalization.
- Measurement of anterior, superior, and posterior TMJ joint spaces.
- Evaluation of cephalometric vertical angles (SN.GOME and Björk sum).
Main Results:
- A statistically significant increase in superior and posterior TMJ joint spaces was observed.
- Vertical cephalometric angles (SN.GOME and Björk sum) also showed a significant increase.
- The magnitude of the observed joint space increase may lack clinical significance.
Conclusions:
- Molar distalization with the distal jet appliance leads to significant increases in superior and posterior TMJ spaces.
- The vertical dimension of the face also increases following this orthodontic procedure.
- While statistically significant, the clinical relevance of these TMJ space changes requires further consideration.
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