A new imaging modality for intraoperative evaluation of sinus floor augmentation.

The aim of this report was to demonstrate the practicability of a new imaging modality, which allows three-dimensional intraoperative imaging and verification of bone-graft position, and to compare it to the currently available imaging systems. The ARCADIS Orbic 3D, a C-arm-based cone-beam computed tomography scanner developed for intraoperative imaging, was used to examine a previously augmented sinus floor, in order to verify the height and width of the augmentation and to determine whether any of the autogenous and synthetic bone-substitute mixture had penetrated the sinus membrane. Visualization of the entire sinus was possible with the aid of multiplanar reconstructions. Data acquisition and processing took 5 min.

Navigated implantation after microsurgical bone transfer using intraoperatively acquired cone-beam computed tomography data sets.

The use of a combination of intraoperative cone-beam computed tomography (CBCT) and a navigation system via a spinal software platform for the navigated implantation of oral implants after microsurgical bone transfer is described. Intraoperative data sets were generated using Arcadis Orbic 3D (Siemens, Medical Solutions, Erlangen, Germany) and immediately transferred to the VectorVision(2) navigation system (BrainLAB, Feldkirchen, Germany) via the NaviLink interface. In two patients who underwent microsurgical bone transfer for midfacial reconstruction, implants were placed using intraoperatively acquired CBCT data sets for planning and navigated insertion. In both cases, successful realization of the planned implant sites was achieved by the guidance of the drill, leading to rehabilitation of both patients. CBCT data generated by mobile systems are sufficient for the planning of implant position, and can be used for navigated insertion using tools originally developed for spinal surgery.

Validation of a new training tool for ultrasound as a diagnostic modality in suspected midfacial fractures.

The aim of this study was to test a previously described training tool for ultrasound for use as a first-line imaging modality. Navigated sonography was performed in 10 patients with midfacial fractures diagnosed using computed tomography (CT). One examiner ranked his sonographic findings regarding the presence of a fracture on six predefined anatomic landmarks on a scale from 1 to 5. These results were correlated with CT findings by displaying fused images. In all but three patients fractures were correctly identified using sonography. In the remaining three patients the examiner was unable to determine whether a fracture was present or not. Normally, these patients would have been subjected to conventional radiographs. Ultrasound proved to be a reliable first-line imaging modality for the investigation of suspected midfacial fractures in daily clinical practice, resulting in decreased radiation exposure since conventional radiographs are omitted. According to this algorithm, patients with sonographically confirmed midfacial fractures are examined for surgical planning using cone-beam CT.

Eruption times of permanent teeth in teenage boys and girls in Izmir (Turkey).

In a study in the Aegean city of Izmir, Turkey, during the summer of 2002, 2101 patients (1046 boys and 1055 girls) were examined. The examination occurred within the framework of a dental check-up performed at two schools and one pre-school unit. The age span ranged from 3.98 to 24.91 years. Sex, age and present permanent teeth were recorded. Wisdom teeth were excluded. The sequence of tooth eruptions differs significantly in the lower and upper jaw, whereas no significant differences existed when comparing the sides of each jaw. The times of tooth eruption is earlier in females than in males. The entire tooth eruption process of the second dentition occurs in females earlier than in males. The tooth eruption in the lower and upper jaw of male and female probands is symmetrical. In comparing the upper and the lower jaw of both genders, it becomes evident that there is a tendency for earlier tooth eruptions in the lower jaw. In respect to the tooth eruption sequence, a change was noted in the upper jaw. Contrary to the reports of other authors, the second premolar has changed places with the canine and erupts prior to this tooth. Otherwise no major differences concerning the sequence of tooth eruptions, when compared to the results gained from other populations, were observed. Concerning the entire dentition, no acceleration of the tooth eruption could be noted. The computed differences of teeth eruption as a mean value calculated over all teeth, was +/- 1 year at maximum, compared to studies from different continents. Oral examination of teeth is a simple tool to calculate tooth eruption intervals. This first investigation on a population of Izmir revealed a change in the eruption sequence of permanent teeth. These findings are relevant for dental treatment planning and forensic odontology and should be reconfirmed at certain intervals.