Prevalence of Middle Mesial Canals and Isthmi in the Mesial Root of Mandibular Molars: An In Vivo Cone-beam Computed Tomographic Study.

INTRODUCTION: Many studies have investigated the morphology of the mandibular molar, but the prevalence of the middle mesial (MM) canal in the mesial root of the mandibular molar is still the subject of controversy. In addition, in previous literature, a true MM canal has not been clearly distinguished from an isthmus between the mesiobuccal and mesiolingual canals. Therefore, the objectives of this study were 2-fold: METHODS: Ninety limited field of view cone-beam computed tomographic scans were observed. One hundred twenty-two mature mandibular first and second molars with no previous root canal treatment, no root resorption, and intact crowns were retrospectively evaluated. Data regarding the sex, age, presence of MM canals, and number of root canals in the mesial root were recorded. RESULT: Of the 122 teeth, 20 (16.4%) had true MM canals. The prevalence of MM canals was 26% in first molars and 8% in second molars (P < .05). The frequency of isthmi in the mesial roots was 64.7%. The frequency of isthmi was higher in second molars, but the difference was not statistically significant (P > .05). CONCLUSIONS: This study showed a high prevalence of mandibular molars with MM canals or isthmi. The detection and biomechanical cleaning of these areas during nonsurgical or surgical root canal treatment are critical.

Incidental Findings on Cone Beam Computed Tomography Studies outside of the Maxillofacial Skeleton.

Objective. To define the presence and prevalence of incidental findings in and around the base of skull from large field-of-view CBCT of the maxillofacial region and to determine their clinical importance. Methods. Four hundred consecutive large fields of view CBCT scans viewed from January 1, 2007, to January 1, 2014, were retrospectively evaluated for incidental findings of the cervical vertebrae and surrounding structures. Findings were categorized into cervical vertebrae, intracranial, soft tissue, airway, carotid artery, lymph node, and skull base findings. Results. A total of 653 incidental findings were identified in 309 of the 400 CBCT scans. The most prevalent incidental findings were soft tissue calcifications (29.71%), followed by intracranial calcifications (27.11%), cervical vertebrae (20.06%), airway (11.49%), external carotid artery calcification (10.41%), lymph node calcification (0.77%), subcutaneous tissue calcification and calcified tendonitis of the longus colli muscle (0.3%), and skull base finding (0.15%). A significant portion of the incidental findings (31.24%) required referral, 17.76% required monitoring, and 51% did not require either. Conclusion. A comprehensive review of the CBCT images beyond the region of interest, especially incidental findings in the base of skull, cervical vertebrae, pharyngeal airway, and soft tissue, is necessary to avoid overlooking clinically significant lesions.

Radiographic manifestations of Mönckeberg arteriosclerosis in the head and neck region.

Mönckeberg sclerosis is a disease of unknown etiology, characterized by dystrophic calcification within the arterial tunica media of the lower extremities leading to reduced arterial compliance. Medial calcinosis does not obstruct the lumina of the arteries, and therefore does not lead to symptoms or signs of limb or organ ischemia. Mönckeberg sclerosis most commonly occurs in aged and diabetic individuals and in patients on dialysis. Mönckeberg arteriosclerosis is frequently observed in the visceral arteries, and it can occur in the head and neck region as well. This report describes a remarkable case of Mönckeberg arteriosclerosis in the head and neck region as detected on dental imaging studies. To the best of our knowledge, this is the first case that has been reported in which this condition presented in the facial vasculature. The aim of this report was to define the radiographic characteristics of Mönckeberg arteriosclerosis in an effort to assist health care providers in diagnosing and managing this condition.

Arrested Pneumatization of the Sphenoid Sinus on Large Field-of-View Cone Beam Computed Tomography Studies.

Arrested pneumatization of the sphenoid sinus is a normal anatomical variant. The aim of this report is to define cone beam computed tomography (CBCT) characteristics of arrested pneumatization of sphenoid sinus in an effort to help differentiate it from invasive or lytic skull base lesions. Two cases are presented with incidental findings. Both studies, acquired for other diagnostic purposes, demonstrated unique osseous patterns that were eventually deemed to be anatomic variations in the absence of clinical signs and symptoms although the pattern of bone loss and remodeling was diagnosed as pneumatization of the sphenoid sinus by a panel of medical and maxillofacial radiologists following contrasted advanced imaging. It is important to differentiate arrested pneumatization of the sphenoid sinus from lesions, such as arachnoid granulations, acoustic neuroma, glioma, metastatic lesions, meningioma, or chordoma, to prevent unnecessary biopsies or exploratory surgeries that would consequently reduce treatment costs and alleviate anxiety in patients.

Incidental findings of skull-base abnormalities in cone-beam computed tomography scans with consultation by maxillofacial radiologists.

INTRODUCTION: Cone-beam computed tomography (CBCT) gives orthodontists and other dental clinicians 3-dimensional information for planning treatment in the craniofacial region. Often overlooked are incidental findings outside the treatment region of interest. METHODS: Two patients with incidental findings of skull-base abnormalities are presented. The orthodontic patient was tentatively diagnosed with a notochordal remnant in the clivus; the implant patient exhibited an empty sella turcica. RESULTS: For the clivus lesion in the orthodontic patient, an artifact was ruled out after a second CBCT image and further distinguished from a fat-containing tumor after magnetic resonance imaging. The impression after magnetic resonance imaging was a notochordal remnant, although chordoma was also included in the differential, warranting a 6-month follow-up magnetic resonance image to confirm the diagnosis. The CBCT study for the implant patient demonstrated an enlarged sella turcica. The impression after the magnetic resonance imaging was an enlarged and partially empty sella with no evidence of a pituitary mass. CONCLUSIONS: Orthodontists and implant surgeons may come across incidental findings outside their area of expertise on CBCT scans, highlighting the importance of appropriate consultation with maxillofacial radiologists. Notochordal remnants may present as nonexpansile intraosseous low-density areas. The challenge in distinguishing these lesions radiographically with chordomas warrants follow-up to confirm a diagnosis. An empty sella is a noteworthy finding because of its potential for endocrine and neuro-ophthalmological disorders despite an asymptomatic presentation.

Skeletal and soft-tissue incidental findings on cone-beam computed tomography images.

Cone-beam computed tomography provides orthodontists with 3-dimensional images of the craniofacial region and valuable information for diagnosis and treatment planning of craniofacial or dental anomalies. However, a narrow focus on the skeletal and dental contributions to malocclusion can cause failure to identify skeletal or soft-tissue pathologies of the craniofacial structures unrelated to the orthodontic concerns. Two cases are presented that demonstrate skeletal and soft-tissue anomalies identified as incidental findings on cone-beam computed tomography scans of asymptomatic orthodontics patients. One patient was diagnosed with craniofacial fibrous dysplasia; the other had an intrahemispheric lipoma. Their cone-beam computed tomography images are presented, along with a literature review on their pathologies.

Cone beam computed tomography imaging in the evaluation of the temporomandibular joint.

A radiological examination is an essential part of the diagnosis and management of temporomandibular joint disease. Accurate evaluation of the TMJ has been difficult due to the superimposition of other structure in convention radio graphs. Cone beam computed tomography provides precise imaging of TMJ anatomy without superimposition and distortion. The CBCT's preciseness enables practitioners to better identify problems, as well for other strategies. Common conditions of the TMJ in which CBCT plays a role are discussed.

Cone beam computed tomography imaging in the evaluation of the temporomandibular joint.

A radiological examination is an essential part of the diagnosis and management of temporomandibularjoint disease. Accurate evaluation of the TMJ has been difficult due to the superimposition of other structure in conventional radiographs. Cone beam computed tomography provides precise imaging of TMJ anatomy without superimposition and distortion. The CBCT's preciseness enables practitioners to better identify problems, as well for other strategies. Common conditions of the TMJ in which CBCT plays a role are discussed.