INTRAMUSCULAR OEDEMA AFTER TRUNCULAR ANALGESIA DIAGNOSED BY MRI: A CASE REPORT AND DIFFERENTIAL DIAGNOSIS OF MOUTH OPENING LIMITATION

F. Cecchetti¹, M. Di Girolamo², L. Baggi¹, D. Mazza¹

¹Department of Social Dentistry and Gnathological Rehabilitation, National Institute for Health, Migration and Poverty
(NIHMP), Roma, Italy;
²Department of Clinical Sciences and Translational Medicine, Tor Vergata University, Roma, Italy

Correspondence to:
Dario Mazza, DDS
Department of Social Dentistry and Gnathological Rehabilitation,
National Institute for Health, Migration and Poverty (NIHMP),
Roma, Italy
e-mail: mzzdra@hotmail.com

Received: 23 May, 2022 Accepted: 19 August, 2022 Copyright: Biolife-Publisher.it © 2022

ISSN: 2038-4106 This publication and/or article is for individual use only and may not be further reproduced without written permission from the copyright holder. Unauthorized reproduction may result in financial and other penalties. Disclosure: All authors report no conflicts of interest relevant to this article.

ABSTRACT

Mouth opening limitation (MOL) is an important clinical sign generally referred to as temporomandibular disorders (TMD) but MOL can also be due to other pathologies as neoformations. The first level’s radiological exam is an orthopantomography that helps the clinician choose the most appropriate second-level exam. MRI is the gold standard for TMD, while multislices CT generally investigates maxillofacial pathologies. Cone beam CT (CBCT) with an appropriate FoV is recommended if a contrast agent is not indicated. Muscle contractures frequently cause MOL as prolonged mouth opening during dental treatment, antalgic contractures due to any infectious-inflammatory process, or after surgery. An MRI investigation of a case of intramuscular oedema after troncular analgesia has never been documented in the literature. A 36-year-old female with MOL (21 mm) with midline deflection to the left side since the last 15 days is presented. The patient reported that she had endodontic therapy on 4.6 after troncular analgesia at the ipsilateral ascending mandibular ramus just before the onset of symptoms. She had never experienced symptoms of TMJ dysfunction a before T2/DPweighted TMJ MRI with T1/T2-weighted scans of the pterygoid muscles in axial and coronal planes with a dedicated coil was performed. The images demonstrate the presence of a reducing disc displacement in the right TMJ and a nonreducing
disc displacement in the left TMJ with a limitation of condyle translation. An inhomogeneous area of isointense in T1 and hyperintense in T2, referable to intramuscular oedema resulting from troncular analgesia, was appreciated at the right internal pterygoid muscle, at the level of the spine of Spix. MRI is an essential method in the differential diagnosis of MOL and allows targeted and resolutive therapy.

KEYWORDS: MRI, pterygoid muscles, temporomandibular disorders