Prevalence of Zygomatic Air Cell Defect using Orthopantomogram

Abstract

INTRODUCTIONPneumatization is the formation of air cavities in bone. Apart from the major paranasal sinuses, air cells may arise singly or in clusters in numerous locations in the skull, including the temporal bone [1]. The nomenclature ZACD is used to denote accessory air cells observed in the zygomatic process of maxilla and articular eminence of the temporal bone, which simulate mastoid air cells [2]. It presents as an asymptomatic, non expansile, non destructive radioluceny on radiographs [3]. Recognition of normal anatomy as well as pathologies can be performed effectively with the utilization of widely used imaging modality that is panoramic radiography as it gives more extensive delineation of oro-facial area [2]. On the basis of radiographic appearance on panaromic radiograph there are three types of ZACD: 1. Unilocular type, 2. Multilocular type, 3. Trabecular type. Unilocular type of ZACD presents as radiolucency with well defined borders, whereas multilocular type appears as numerous small cavities within, which resemble mastoid air cells. The third variety is trabecular type which appears as multilocular entity with internal bony striations [1]. At the point when ZACDs have been exhibited preoperatively on a radiograph, these may be contraindications to perform surgical strategies, for example, eminoplasty or eminectomy for the treatment of mandibular dislocations as they get to be potential pathways for intracranial infections [3].The area of research that is the prevalence of ZACD in North Indian population is under investigated till date and presently has a limited empirical knowledge base. Therefore, the present study was conducted to determine the prevalence of ZACD amongst North Indian population and also to establish the dominant location and type. MATERIALS AND METHODSThe present study material comprised of 2500 panoramic radiographs of patients aged between 19 and 78 years, who visited Department of Oral Medicine and Radiology during the period of January 2009 to December 2013. All radiographs were obtained with Gendex Orthoralix 9200 (America) DDE Digital Pan/Ceph System panoramic radiographic machine operating at 65-80 kVp, 10 mA and 16 s. Cases in which the zygomatic arch was not adequately displayed for anatomical or technical reasons were excluded from the sample and did not constitute part of the sample. All persons gave their informed consent prior to their inclusion in a study. All patients had no severe bone disease including tumor, cyst or fracture. Selection criteria for the acquisition of panoramic radiographs included caries, pain, missing or supernumerary teeth, mixed dentition analysis, periodontal disease, third molar extraction, extensive restorative dental procedures, prosthodontic evaluation, orthodontic evaluation and TMJ problems. Subsequently, ZACDs were classified depending on: (1) age and gender, (2) the location: unilateral or bilateral and (3) the appearance: unilocular or multilocular. Radiographs were examined in subdued ambient lighting using transmitted light fr...

Volumetric Analysis of the Articular Eminence Pneumatization Using Cone Beam Computed Tomography

“…12 Moreover, using panoramic radiography Shokri et al 20 and Khojastepour et al 8 found a frequency of 6.2% (98 cases) and 2.1% (64 cases) respectively in Iran using panoramic radiography. In India, Kishore et al 21 and Patil et al 22 found similar frequencies of 2.5% (63 cases) and 1.82% (141 cases) respectively. Orhan et al 2 reported a similar frequency of 1.88% (19 cases) to the ones reported by Hofmman et al 23 with a frequency of 2.38% (20 cases) and of 1.85% (20 cases) respectively in Germany (Table 4).…”

Zygomatic Air Cell Defect – Magnetic Resonance Imaging of the Temporomandibular Joint Compared with Panoramic Radiographs

“…There is a series of studies which retrospectively evaluated panoramic radiographs, with a determined ZACD prevalence of 1.03% to 3.42% ( 1 , 8 - 14 ). While the subjects of comparative radiology in our study were patients with TMJ disorder, recent studies of ZACD were more based on determining its prevalence by including larger groups of dental patients without previous symptomatology related to the stomatognathic system.…”

“…In general, ZACD rarely occurs with additional clinical symptomatology, and it was found accidentally on different radiological images of TMJ area, as described in clinical reports of patients with temporomandibular disorder (TMD) ( 7 ). There are many studies on ZACD prevalence assessed on panoramic radiograph samples ( 8 - 14 ). As in general skeletal radiology, TMJ transcranial diagnosis and multi-slice computed tomography (MSCT) were common tools for evaluation of ZACD, as well as cone beam computed tomography (CBCT) ( 15 - 18 ).…”

A population-based retrospective study of zygomatic air cell defect in Bengaluru

“…Small bony cavities are formed during the pneumatization of normal periosteum. [4] It is a process of asymptomatic expansion of cavities containing air within the bone and temporal bone, ethmoid bone, and mastoid cells are the most important sites of maxillofacial region with infrequent sites including middle ear, squamomastoid, petrous apex, and perilabyrinthine. [5] ZACD appears to be comparable with mastoid air cells and has been represented as accessory air cells which do not cross zygomaticotemporal suture anteriorly and are found to be present within the limitation of zygomatic process and articular eminence of the temporal bone.…”