Oscar Jacob was the first to describe osteochondroma of the coronoid process, naming it "Jacob disease." Jacob disease rarely occurs in the oral and maxillofacial regions. The tumor usually grows progressively, leading to a mushroom-shaped enlargement of the process, and a joint-like structure is found between the coronoid process and the inner aspect of the zygomatic arch. Most of these lesions grow like a mushroom on, and do not destroy, the coronoid process. The major symptoms include restricted mouth opening and morphological changes to the zygoma. The authors present a case report on an 18-year-old male patient with pain in the right zygoma. Interincisal maximum mouth opening was 51 mm. An intraoral coronoidectomy was performed.

Eagle's syndrome is a rare condition associated with the temporal styloid process hypertrophy (Eagle, 1937). It is in most cases asymptomatic, but may be accompanied by dysphagia, pharyngeal or head and neck pain due to neurovascular structure compression. The current study aims to present and discuss the etiology of a possible case of Eagle's syndrome from an Italian ossuary. Skull OC 002/08 shows a unilateral hypertrophic styloid process (48 mm long; 5-7 mm thick). Areas of remodel-ed periosteal swelling are visible at the stylohyoid and stylopharyngeus muscles' insertion, along with evidence of healed trauma to both nasal bones and a depressed fracture on the upper left portion of the frontal. Several factors have been proposed as possible causes of styloid elongation, including anatomical variation, aging and trauma. Evidence of unilateral styloid hypertrophy in association with healed cranial trauma in OC 002/08 suggests a traumatic etiology for the condition.

Eagle's syndrome, an uncommon sequela of an elongated styloid process, can manifest itself as a sensation of a foreign body in the throat and a retrogoniac or anterolateral neck pain often referred to the TMJ and the ear. When treating patients affected by temporomandibular disorders (TMD), complaining of atypical orofacial pain, and with a concomitant radiographic finding of a bilaterally elongated styloid, the possible coexistence of Eagle's syndrome should always be considered. The aim of this review is to present an overview of the epidemiology, pathophysiology, diagnosis, and therapy for Eagle's syndrome and to help the clinician in differential diagnosis with other conditions that can provide similar signs and symptoms.

In a prior study, the spatial relationship of the mandibular condyle was studied through a cephalogram based on laminographies of the temporomandibular joint (TMJ). The present method was developed with the aim of analyzing TMJ morphology and the spatial relationship of the mandibular head within the mandibular fossa, considering references far from these structures, as they may suffer shape alterations. This study was conducted in view of the importance of the study of morphology and the hard structures relationship, which constitutes the temporomandibular joint. Its purpose is to validate a new TMJ cephalogram method by analyzing joints with and without alterations in the orientation of the condylar axis growth. Sixty joints were studied through laminographies in maximal occlusion, examining those joints with and without alterations in the orientation of the axis during condylar growth for subsequent analysis. Results showed that those joints were in a posterior position and rotation of the mandibular head, and that they presented a greater inclination in the articular eminence compared to joints without alterations in the axis orientation. Moreover, a new cephalometric method could be validated, demonstrating that changes in the condylar axis orientation imply pathology; they could also be correlated with changes in the condylar position and in the glenoid fossa morphology.

This study aimed to investigate the prevalence of clinical features of temporomandibular disorders (TMD) in patients with fibromyalgia. The test group (FMG) consisted of 40 women with fibromyalgia (FM) compared to the control group of 40 healthy subjects using the research diagnostic criteria for temporomandibular disorders (RDC/TMD). The variables were compared using Fisher's exact test and a Mann-Whitney test. Facial pain was reported by 85% of the FM group, and 77.5% were diagnosed with myofascial TMD. Muscle pain during jaw movements, daytime bruxism/clenching, and limited mouth opening were significantly higher in the test group. There was no difference between groups in: (1) joint noises; (2) sleep bruxism/clenching; and (3) excursive or non-excursive movements. Classic signs of TMD, such as joint noise and self-reporting of clenching at night, are not associated with fibromyalgia syndrome as demonstrated in the current study. However, the self-reported daytime parafunctions, muscle pain in jaw movements, and limited mouth opening are features of the patients in the current study. This study revealed specific muscle involvement of TMD is also presence in FM.

The current study aims to analyze and quantify the effects of different registration techniques on the reproducibility of condyle position and the influence of stabilization splint therapy on the technique's reproducibility. Three-dimensional electronic-condylar-position analysis (EPA) with an ultrasound-based jaw-tracking system was recorded during intermaxillary registration of manually guided centric relation (CR), maximal intercuspation (MI), and clenching-force-dependent Gothic arch tracing guided centric relation (DIR method) before (T0) and after (T1) splint therapy. Patients were supplied with a stabilization splint for three months on the basis of the DIR registration. Participants were 26 asymptomatic volunteers with a mean age of 30.6 +/- 9.5 years. The registration technique was found to have a significant (p = 0.001) effect on condylar displacement in all axes before, and in X- and Y-axes after splint therapy. Condyles during DIR were found to be in a more anterior-inferior position compared with CR and MI, with the condyles in the latter position being likewise more anterior than in CR. There were significant (p < 0.03) differences in reproducibility of the condyle position dependent on the technique, both at T0 and T1. The DIR method showed the highest reproducibility, followed by MI and CR. There was no significant effect of time of investigation on the technique's reproducibility.

The aim of this study was to evaluate the effects of disc displacement (DD) and its progression on dentocraniofacial morphology in symptomatic patients, and to compare the results with asymptomatic volunteers. Female patients with DD, diagnosed with magnetic resonance imaging (MRI) and posteroanterior cephalometric analysis, were included in this study. Subjects were grouped as follows: control group with bilateral normal disc position (group 1, n=20), unilateral DD with reduction (group 2, n=17), bilateral DD with reduction (group 3, n=32), unilateral DD without reduction (group 4, n=16), and bilateral DD without reduction (group 5, n=19). Thirteen cephalometric variables were measured. A significant increase in the ANS (Anterior nasal spine)-Me (Menton)-MSP (Midsagittal plane) angle in unilateral DD groups and decreases in the Ag (Antegonial notch)-Me dimension on the affected side in all DD groups were observed. Also, the maximum values of the Me-MSP dimension and ANS-Me-MSP angle were observed in group 4. The results of this study showed that the deviation of the menton point toward the disc displacement side causes a mandibular asymmetry. It can be concluded from these results that the presence of DD in female patients affects facial morphology, and its progression makes the differences more significant and remarkable. These results emphasize the importance of early diagnosis and treatment in the management of DD.

Although they are widely used as diagnostic signs of temporomandibular disorders, mandibular border movements reflect not only condylar movement, but also other factors. In the present study, the authors investigated the effect of craniofacial morphology on three different mandibular border movements: maximum jaw opening, maximum jaw protrusion, and maximum jaw laterotrusion. One hundred female subjects were selected from outpatients visiting the orthodontic clinic of Okayama University Hospital. The mandibular border movements were measured using an optical recording system in three dimensions as six degrees of freedom. The craniofacial morphology was evaluated using lateral cephalograms. The results suggest that craniofacial morphology had different influences on each mandibular border movement. In particular, during maximum jaw laterotrusion, lower incisor movement strongly reflected condylar movement, and the influence of craniofacial morphology on mandibular border movement was minimal. Therefore, lower incisor movement during maximum jaw laterotrusion appears suitable to evaluate condylar movement.

This position paper, as developed by a Task Force of the American Academy of Craniofacial Pain on Mandibular Advancement Oral Appliance Therapy for Snoring and Obstructive Sleep Apnea, contains recommendations for dentists engaged in the management of patients with snoring and obstructive sleep apnea utilizing mandibular advancement oral appliances. The recommendations are supported by current scientific evidence, published standards and guidelines, and expert panel consensus. Snoring and obstructive sleep apnea (OSA) affects millions of people. Oral appliance therapy (OAT) is recognized as an effective therapy for many with primary snoring and mild to moderate OSA, as well as those with more severe OSA who cannot tolerate positive airway pressure (PAP) therapies. Dentists are playing a much larger role in the screening and management of patients with snoring and OSA as part of a multi-disciplinary team. It is also recognized that OAT has the potential to cause untoward side effects, including temporomandibular joint (TMJ) pain and dysfunction. The present paper highlights the need for dentists who manage patients using mandibular advancement OAT to be competent in the assessment, diagnosis and management of temporomandibular disorders (TMDs) and craniofacial pain disorders. The authors of this article are all clinically engaged in the management of patients with snoring and OSA, and reached consensus based on their review of the current evidence, published guidelines and clinical experience. It is the opinion of the authors that dentists experienced and knowledgeable in the assessment, diagnosis and management of TMD and craniofacial pain applying this knowledge to the management of patients with snoring and OSA using OAT will provide their patients with the best prognosis and most successful treatment outcomes.