Mandibular fracture patterns consistent with posterior maxillary fractures involving the posterior maxillary sinus, pterygoid plate or both: CT characteristics

Lateral Pterygoid Muscle Biometric Modifications in Pterygoid Process Fractures Associated With Mandibular Fractures

PURPOSE

Pterygoid process fractures (PPFs) are classically associated with Lefort fractures but can also be encountered in association with other facial fractures such as mandibular fractures. The aim of this study was to estimate the frequency of PPFs associated with mandibular fractures and identify factors associated with PPF.

MATERIALS AND METHODS

We conducted a retrospective cross-sectional study using computed tomography scanning of patients having a mandibular fracture between November 2018 and April 2020. PPFs were classified using the classification by An et al. Volume, length, and width of both lateral pterygoid muscles have been evaluated by using an image processing software. Study population has been divided into 2 groups: fracture of pterygoid process or the absence of PPF. To evaluate the implication of lateral pterygoid muscle in the pathophysiology of PPF, we compared lateral pterygoid muscle volume, its maximal length, and width between both groups. Patients with bilateral fractures were excluded from this analysis.

RESULTS

About 304 patients with at least 1 mandibular fracture have been included in this study. About 18 patients presenting an association of mandibular fracture and PPF were finally selected. About 83.33% of the patients were concerned by a fracture of the posterior part of the mandible. The PPF was classified as type IIA by the classification of An et al for 94.4% of patients. The lateral pterygoid muscle volumes were significantly larger on the side of the PPF (P = .02). However, there were no significant differences in the maximum length (P = .49) and width (P = .1) of lateral pterygoid muscle.

CONCLUSIONS

Our study showed an association between mandibular fractures (mainly ipsilateral posterior) and isolated PPF through a lateral pterygoid muscle volume increase.

Multidetector CT of Mandibular Fractures, Reductions, and Complications: A Clinically Relevant Primer for the Radiologist

After the nasal bones, the mandible is the second most common site of facial fractures, and mandibular fractures frequently require open reduction. In the trauma injury setting, multidetector computed tomography (CT) has become the cornerstone imaging modality for determining the most appropriate treatment management, fixation method, and surgical approach. Multidetector CT is also used to assess the adequacy of the reduction and evaluate potential complications in the postoperative period. For successful restoration of the mandible's form and function, as well as management of posttraumatic and postoperative complications, reconstructive surgeons are required to have a detailed understanding of mandibular biomechanics, occlusion, and anatomy. To provide added value in the diagnosis, treatment planning, and follow-up of mandibular fractures, radiologists should be aware of these concepts. Knowledge of the techniques commonly used to achieve occlusal and anatomic reduction and of the rationale behind the range of available treatment options for different injury patterns-from isolated and nondisplaced fractures to multisite and comminuted fractures-also is essential. This article focuses on the use of multidetector CT for pre- and postoperative evaluation of mandibular fractures and outlines fundamental concepts of diagnosis and management-beginning with an explanation of common fracture patterns and their biomechanical underpinnings, and followed by a review of the common postoperative appearances of these fractures after semirigid and rigid fixation procedures. Specific considerations regarding fractures in different regions of the tooth-bearing and non-tooth-bearing mandible and the unique issues pertaining to the edentulous atrophic mandible are reviewed, and key features that distinguish major from minor complications are described. (©)RSNA, 2016.

Coincidence of mandibular fractures with isolated posterior maxillary sinus fractures

BACKGROUND/AIM

There are no data available to show whether there is a relationship between mandibular fractures and isolated fractures of the posterior and/or lateral walls of the maxillary sinus. The aim of this study was to determine whether there is a coincidence between these fracture patterns.

METHODS

Four hundred large volume cone beam computed tomography scans (CBCT) of patients with a fracture of the mandible between 2008 and 2013 were analyzed retrospectively. Patients with multiple midfacial fractures were excluded. The radiographic findings were correlated with epidemiological and clinical data of the patients such as gender, age, treatment methods, or complications.

RESULTS

The most frequent fracture sites of the mandible were the jaw angle, the parasymphysis region, and the condyle. Nineteen of the 400 patients (4.75%) had an isolated fracture of the lateral and/or posterior maxillary sinus. Odds-ratio analysis revealed a high tendency for significant correlation of condylar process fractures with isolated maxillary sinus fractures. Chi-square test demonstrated a P-value near statistical significance (P=.054). No other fracture site of the mandible could be associated with an isolated fracture of the maxillary sinus.

CONCLUSION

A condylar process fracture of the mandible after trauma without any further injury of the midface may be associated with an isolated fracture of the lateral and/or posterior maxillary sinus.