Three-Dimensional Radiographic Evaluation of the Malar Bone Engagement Available for Ideal Zygomatic Implant Placement

Abstract

Zygomatic implant rehabilitation is a challenging procedure that requires an accurate prosthetic and implant plan. The aim of this study was to evaluate the malar bone available for three-dimensional zygomatic implant placement on the possible trajectories exhibiting optimal occlusal emergence. After a preliminary analysis on 30 computed tomography (CT) scans of dentate patients to identify the ideal implant emergencies, we used 80 CT scans of edentulous patients to create two sagittal planes representing the possible trajectories of the anterior and posterior zygomatic implants. These planes were rotated clockwise on the ideal emergence points and three different hypothetical implant trajectories per zygoma were drawn for each slice. Then, the engageable malar bone and intra- and extra-sinus paths were measured. It was possible to identify the ideal implant emergences via anatomical landmarks with a high predictability. Significant differences were evident between males and females, between implants featuring anterior and those featuring posterior emergences, and between the different trajectories. The use of internal trajectories provided better bone engagement but required a higher intra-sinus path. A significant association was found between higher intra-sinus paths and lower crestal bone heights.

Complete-Arch Accuracy of Four Intraoral Scanners: An In Vitro Study

“…Impressions obtained with conventional materials (polyether and polyvinylsiloxane) are the most common procedures in clinical practice; conventional workflows and CAD/CAM technologies can be combined through indirect digitalization [ 20 ]. However, new digital techniques allow the full digitalization of the workflow—intraoral digital scanners, through direct scanning, can create a virtual 3D model [ 21 , 22 ]. The main feature to be evaluated in an intraoral scanner is accuracy, which is the result of the analysis of trueness and precision [ 23 ].…”

Three-dimensional Measuring of Zygomaticomaxillary Complex Symmetry after Fixation of Unilateral Zygomaticomaxillary Complex Fracture

“…In addition, the spatial position of the affected side can be recorded in accordance with the reference to the normal side pre-and postoperatively (17) . The precision and reproducibility of these landmarks have been extremely studied by some authors, (39,40) who compared the results of the unaffected side pre-and postoperatively and they found that there was no actually difference in the radiographic points positions . Similarly in this study, the distance between the four pairs of anatomical landmarks and the three reference planes (x, y, and z) were measured pre-and postoperatively, and it was found that these landmarks can be easily marked and quantitatively assessed the degree of fracture displacement and the accuracy of ZMC reduction and fixation, as also reported by other studies (39,41) .…”

Comparative Analysis of the Stability of Prosthetic Screws under Cyclic Loading in Implant Prosthodontics: An In Vitro Study

“…In the last few decades, the screw-retained prosthesis on implants has become increasingly common for the rehabilitation of the totally edentulous patients [1][2][3]. Multiple solutions for the rehabilitation of upper and lower jaw were proposed and accepted in literature, basing on the entity of bone atrophy, the pneumatization of maxillary sinus, the quantity of bone available and the position of inferior alveolar nerve and mental foramina [4][5][6][7]. The All-On-Four technique for the rehabilitation of completely edentulous mandibles, initially proposed by Malo et al [8] is nowadays used by several clinicians [9][10][11] in order to reach the correct masticatory and speech functions, as well as an optimal prosthetic support, and to re-establish an acceptable situation for the patient [12].…”