Unusually severe limitation of the jaw attributable to fibrodysplasia ossificans progressiva: a case report with cone-beam computed tomography findings

Limitations of Jaw Movement in Fibrodysplasia Ossificans Progressiva: A Review

Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disorder characterized by heterotopic ossification (HO) of the skeletal muscles, fascia, tendons and ligaments. Patients often experience limitations in jaw function due to HO formation in the maxillofacial region. However, no studies have yet analyzed the age of onset and location of HO and the type of restrictions it may yield in the maxillofacial region. The aim of this study was to evaluate all existing literature on the site of onset of HO and associated functional restrictions of the jaw. To this end, a scoping review was performed focusing on limitations of jaw movement in FOP patients. The literature search resulted in 725 articles, of which 30 articles were included for full study after applying the exclusion criteria. From these articles 94 FOP patients were evaluated for gender, age, presence and age at which HO started in the maxillofacial region, location of HO, whether HO was caused spontaneous or traumatic and maximum mouth opening. Formation of HO is slightly more common in female patients compared to male patients, but the age of HO onset or the maximum mouth opening does not differ between genders. Trauma-induced HO occurred at a significantly younger age than spontaneous HO. Interestingly, a difference in maximum mouth opening was observed between the different ossified locations in the maxillofacial region, with ossification of the masseter muscle resulting in the smallest and ossification of the zygomatic arch resulting in the largest maximum mouth opening. This review revealed that the location of the maxillofacial region affected by HO determines the degree of limitations of the maximum mouth opening. This finding may be important for establishing clinical guidelines for the dental management of FOP patients.

Temporomandibular joint ankylosis—“Knowing when not to operate”: Case report and qualitative systematic review of literature

Temporomandibular joint ankyloses (TMJA) may manifest in patients with several predisposing systemic conditions. A case of extraarticular TMJA is presented in a patient diagnosed with fibrodysplasia ossificans progressive (FOP) is presented. The features, diagnosis, and management of TMJA superimposed on this condition are presented through a qualitative systematic review of literature.

Unresolving trismus following third molar surgery: Report of a case of fibrodysplasia ossificans progressiva with review of literature

BACKGROUND

Trismus is a problem commonly encountered by the dental practitioner. It has a number of potential causes, and its treatment will depend on the cause. However, there are very few reports of trismus due to fibrodysplasia ossificans progressiva (FOP) following third molar surgery.

CLINICAL PRESENTATION

FOP is a rare human genetic disorder with characteristic clinical features like progressive formation of extraskeletal bone or heterotopic ossification and congenital malformation of the great toes.

CLINICAL SIGNIFICANCE

It is troublesome to the maxillofacial surgeon, that minimal manipulation and minor surgery can induce bone formation in soft tissues of the head and neck region, particularly the masticatory muscles and the temporomandibular joint. This paper presents a case of severe trismus following third molar extraction, intractable by routine treatment methods, which was later diagnosed as FOP.

Restricted Mandibular Movement Attributed to Ossification of Mandibular Depressors and Medial Pterygoid Muscles in Patients With Fibrodysplasia Ossificans Progressiva: A Report of 3 Cases

Fibrodysplasia ossificans progressiva (FOP) is an extremely rare genetic condition characterized by congenital malformation and progressive heterotopic ossification (HO) caused by a recurrent single nucleotide substitution at position 617 in the ACVR1 gene. As the condition progresses, HO leads to joint ankylosis, breathing difficulties, and mouth-opening restriction, and it can shorten the patient's lifespan. This report describes 3 cases of FOP confirmed by genetic testing in patients with restricted mouth opening. Each patient presented a different onset and degree of jaw movement restriction. The anatomic ossification site of the mandibular joint was examined in each patient using reconstructed computed tomographic (CT) images and 3-dimensional reconstructed CT (3D-CT) images. A 29-year-old woman complained of jaw movement restriction since 13 years of age. 3D-CT image of the mandibular joint showed an osseous bridge, formed by the mandibular depressors that open the mouth, between the hyoid bone and the mentum of the mandible. A 39-year-old man presented with jaw movement restriction that developed at 3 years of age after a mouth injury. 3D-CT image of the jaw showed ankylosis of the jaw from ossification of the mandibular depressors that was worse than in patient 1. CT images showed no HO findings of the masticatory muscles. To the authors' knowledge, these are the first 2 case descriptions of the anatomic site of ankylosis involving HO of the mandibular depressors in the jaw resulting from FOP. In contrast, a 62-year-old bedridden woman with an interincisal distance longer than 10 mm (onset, 39 years of age) had no HO of the mandibular depressors and slight HO of the medial pterygoid muscle on the right and left sides. These findings suggest that restricted mouth opening varies according to the presence or absence of HO of the mandibular depressors.

Stone man: a case report

Fibrodysplasia ossificans progressiva (FOP) is a rare hereditary connective tissue disease characterized by the progressive ectopic ossification of ligaments, tendons, and facial and skeletal muscles throughout life. Symptoms begin in childhood as localized soft tissue swellings. Immobility and articular dysfunction appear with involvement of the spine and proximal extremities. The temporomandibular joint (TMJ) is a critical component involved in the maxillofacial region, resulting in severe limitation of masticatory function, although TMJ involvement is rare. The aim of this article is to present a 28-year-old man with dental problems and slowly progressive limitation of motion in the jaw, knees, shoulders and hips as well as neck distortion.