Cone beam computed tomography - Frequency and exposure settings at University (Dental) hospitals in Central and Northern Europe.

Purpose: To investigate the frequency of CBCT scans, the exposure settings, volume sizes and the patient demographics (age and sex) of patients undergoing CBCT scans in university-based dental hospitals in different European countries over a one-year period.

Method: Eight University Dental Hospitals from eight countries in central and northern Europe agreed to collect data from their CBCT-databases. Exposure data including field of view (FOV), dose area product (DAP) and optimization settings plus (anonymous) age and sex of the patients were collected for the entire year 2023.

Comparison of the Effective Radiation Dose in the Region of the Facial Skull Between Multidetector CT, Dental Conebeam CT and Intraoperative 3D C-Arms.

Study Design: Experimental single-centre study of X-ray absorption using a phantom skull.

Objective: This experimental study aimed to compare the radiation doses of different 3D imaging devices used in maxillofacial surgery, including one Multidetector CT (MDCT), two Conebeam CT (CBCT) and four intraoperative 3D C-arms.

Methods: Thermoluminescent dosimeters (TLD) were used to determine the absorbed radiation in an Alderson-Rando phantom skull.

A content-aware chatbot based on GPT 4 provides trustworthy recommendations for Cone-Beam CT guidelines in dental imaging.

Objectives: To develop a content-aware chatbot based on GPT-3.5-Turbo and GPT-4 with specialized knowledge on the German S2 Cone-Beam CT (CBCT) dental imaging guideline and to compare the performance against humans.

Methods: The LlamaIndex software library was used to integrate the guideline context into the chatbots.

Inductively Coupled Intraoral Flexible Coil for Increased Visibility of Dental Root Canals in Magnetic Resonance Imaging.

Objectives: Accurate visualization of dental root canals is vital for the correct diagnosis and subsequent treatment. This work assesses the improvement of a dedicated new coil for dental magnetic resonance imaging (MRI) in comparison to conventional ones in terms of signal-to-noise ratio (SNR) and visibility.

Materials And Methods: A newly developed intraoral flexible coil was used to display dental roots with MRI, and it provides improved sensitivity with a loop design and size adjusted to a single tooth anatomy.

Evaluation of skin doses for cone-beam computed tomography in dentomaxillofacial imaging: A preclinical study.

Purpose: Evaluation of skin organ doses in six different cone-beam computed tomography scanners (CBCT) dedicated to dentomaxillofacial imaging. Our hypothesis is that the dose varies between different devices, protocols and skin areas.

Materials And Methods: An anthropomorphic adult head and neck phantom was used to which a dosimeter (Waterproof Farmer® Chamber, PTW, Freiburg, Germany) was attached to anatomic landmarks of both parotid glands, both ocular lenses, the thyroid gland and the neurocranium.

Intraoperative marking of the tumour resection surface for improved radiation therapy planning in head and neck cancer: preclinical evaluation of a novel liquid fiducial marker.

Objective: To evaluate a novel liquid fiducial marker for intraoperative marking of the tumour resection surface in oral cancer patients to facilitate precise postoperative delineation of the interface between the tumour resection border and reconstructed tissue for intensity-modulated radiation therapy.

Methods: A total of 200 markers were created by injecting the volumes of 10 µl, 20 µl, 30 µl, 40 µl and 50 µl of a liquid marker composed of sucrose acetoisobutyrate (SAIB) and iodinated sucrose acetoisobutyrate (x-SAIB) into the soft tissue of porcine mandible segments. Visibility of the resulting markers was quantified by threshold-based segmentation of the marker volume in CT- and CBCT imaging and by a comparison of signal intensities in MRI.

Vascularized scapula and latissimus dorsi flap for CAD/CAM assisted reconstruction of mandibular defects including the mandibular condyle: technical report and clinical results.

Background: Reconstruction of mandibular continuity and function after tumor resection is challenging, particularly in cases including the mandibular condyle. Various approaches for reconstruction after disarticulation resection have been reported. However, the scapula flap has received little attention as a treatment option in these cases.

Numb Chin as Signal for Malignancy-Primary Intraosseous Diffuse Large B-Cell Lymphoma of the Mandible.

Malignant lymphomas are about 5% of all malignant tumors. Extranodal non-Hodgkin's lymphomas (NHLs) are found in 26% of these cases. Lymphomas of the head-and-neck area occur in 2%-3% of all malignancies, with 28% with an extranodal manifestation.

Planning of skull reconstruction based on a statistical shape model combined with geometric morphometrics.

Purpose: Virtual reconstruction of large cranial defects is still a challenging task. The current reconstruction procedures depend on the surgeon's experience and skills in planning the reconstruction based on mirroring and manual adaptation. The aim of this study is to propose and evaluate a computer-based approach employing a statistical shape model (SSM) of the cranial vault.

Efficacy of Stannous Ions on Enamel Demineralization under Normal and Hyposalivatory Conditions: A Controlled Randomized in situ Pilot Trial.

The study aim was to investigate the effect of antierosive agents on enamel under normal and hyposalivatory conditions. This double-blind crossover in situ pilot study evaluated 4 toothpastes: placebo (0 ppm F), sodium fluoride (NaF, 1,450 ppm), stannous/sodium fluoride (SnF/NaF, 1,450 ppm F-, 1,090 ppm Sn2+), and sodium fluoride, stannous chloride and chitosan (NaF/Sn/Ch, 1,450 ppm F-, 3,500 ppm Sn2+, 0.5% Ch).

Navigation accuracy after automatic- and hybrid-surface registration in sinus and skull base surgery.

Objective: Computer-aided-surgery in ENT surgery is mainly used for sinus surgery but navigation accuracy still reaches its limits for skull base procedures. Knowledge of navigation accuracy in distinct anatomical regions is therefore mandatory. This study examined whether navigation accuracy can be improved in specific anatomical localizations by using hybrid registration technique.

Virtual reconstruction of midface defects using statistical shape models.

Purpose: This study evaluates the accuracy of a statistical shape model (SSM) for virtual fracture reconstruction of the lateral midface.

Materials And Methods: A uniform bony defect of the right zygoma was created. A virtual reconstruction was performed by using the standard procedure of mirroring the unaffected to the affected side (Group I) and by using the statistical model based on 178 pathologically unaffected CT scans (Group II).

Vitamin D deficiency in early implant failure: two case reports.

An association between vitamin D deficiency and early dental implant failure is not properly verified, but its role in osteoimmunology is discussed. This article illustrates two case reports with vitamin D deficiency and early implant failure. Prior to implant placement, the first patient received crestal bone grafting with autologous material.

The Influence of Torque Tightening on the Position Stability of the Abutment in Conical Implant-Abutment Connections.

The influence of repeated system-specific torque tightening on the position stability of the abutment after de- and reassembly of the implant components was evaluated in six dental implant systems with a conical implant-abutment connection. An established experimental setup was used in this study. Rotation, vertical displacement, and canting moments of the abutment were observed; they depended on the implant system (P = .

Analytical and experimental position stability of the abutment in different dental implant systems with a conical implant-abutment connection.

Objectives: Position stability of the abutment should be investigated in four implant systems with a conical implant-abutment connection.

Materials And Methods: Previously developed formulas and an established experimental setup were used to determine the position stability of the abutment in the four implant systems with a conical implant-abutment connection and different positional index designs: The theoretical rotational freedom was calculated by using the dimensions of one randomly selected implant per system for approximated geometric models. Experimentally, the rotation, the vertical displacement, and canting moments of the abutment after multiple repositioning and hand tightening of the abutment screw were investigated.