Comprehensive virtual orthognathic planning concept in surgery-first patients.

The surgery-first concept is becoming increasingly popular in orthognathic surgery since it offers major advantages such as a reduction of treatment duration and an increase in patient satisfaction by eliminating phases of presurgical orthodontic decompensation. Here, we present a novel interdisciplinary pathway of a fully virtual orthodontic-surgical planning concept in a surgery-first setting using a 3D-printed cutting guide and a customised maxillary implant for the Le Fort I osteotomy as well as a CAD/CAM-based stereolithographic final splint. Patient data from cone-beam computed tomography of the skull and a full arch dental scan were processed using the OnyxCeph software (Image Instruments).

Comparison of automated digital Peer Assessment Rating compared with measurements performed by orthodontists, dental students, and assistants using plaster, additive manufactured, and digital models.

Background: There are little scientific data on fully automated Peer Assessment Rating (PAR); this study compares a number of PAR scoring methods to assess their reliability.

Objectives: This investigation evaluated PAR scores of plaster, 3D printed, and virtual digital models scored by specialist orthodontists, dental auxiliaries, undergraduate dental students,and using a fully automated method.

Materials And Methods: Twelve calibrated assessors determined the PAR score of a typodont and this score was used as the gold standard.

Impact of thyroid gland shielding on radiation doses in dental cone beam computed tomography with small and medium fields of view.

Objective: The purpose of this study was to evaluate the impact of thyroid gland shielding on radiation doses in dental cone beam computed tomography (CBCT) with small and medium fields of view (FOVs).

Study Design: Six CBCT protocols were investigated by exposing an adult anthropomorphic male phantom head without and with thyroid shielding, using 4 small (4 × 5 cm) and 2 medium (10 × 6 cm) FOVs. Twenty metal oxide semiconductor field-effect transistor dosimeters were placed in the phantom head to measure absorbed doses and calculate equivalent doses at 11 sites.

Evaluation of various low-dose cone-beam computed tomography protocols in the diagnosis of specific condylar defects.

Introduction: This study aimed to determine the identifiability and measurement accuracy of defined bony defects of the temporomandibular joint (TMJ) in cone-beam computed tomographies, depending on different milliampere-second (mAs)-reduced protocols.

Methods: Defined artificial defects were prepared on 30 condyles from 15 intact pig heads, with a maximum of surrounding soft tissue preserved. Three-dimensional imaging was performed using ProMax 3D Mid (Planmeca, Helsinki, Finland).

Modern 3D cephalometry in pediatric orthodontics-downsizing the FOV and development of a new 3D cephalometric analysis within a minimized large FOV for dose reduction.

Objectives: Dose reduction achieved by downsizing the field of view (FOV) in CBCT scans has brought no benefit for pediatric orthodontics, until now. Standard 2D or 3D full-size cephalometric analyses require large FOVs and high effective doses. The aim of this study was to compare a new 3D reduced-FOV analysis using the Frankfurt horizontal (FH) plane as reference plane with a conventional full-size analysis using the Sella-Nasion (S-N) plane as reference plane.

Does ambient light affect the accuracy and scanning time of intraoral scans?

Statement Of Problem: Intraoral scanners (IOSs) are based on light-optical imaging methods. However, little is known about whether the ambient light in dental practices influences the accuracy and scanning time of the IOS.

Purpose: The purpose of this in vitro study was to investigate the influence of different illuminations on the accuracy of 4-unit and complete-arch scans of 6 IOSs.

Dimensional accuracy of extrusion- and photopolymerization-based 3D printers: In vitro study comparing printed casts.

Statement Of Problem: Reliable studies comparing the accuracy of complete-arch casts from 3D printers are scarce.

Purpose: The purpose of this in vitro study was to investigate the accuracy of casts printed by using various extrusion- and photopolymerization-based printers.

Material And Methods: A master file was sent to 5 printer manufacturers and distributors to print 37 identical casts.

Suitability and accuracy of CBCT model scan: an in vitro study.

Plaster casts can be digitized with desktop scanners, intraoral scanners, and recently also with cone beam computed tomography (CBCT). The aim of this study was to investigate the accuracy of five different CBCT devices digitizing a plaster cast. A study cast serving as a patient was made using the double mix impression technique, and the impression was poured out with plaster.

An in-vitro study comparing the accuracy of ?full-arch casts digitized with desktop scanners.

Objective: The purpose of this study was to evaluate the accuracy of full-arch scans using 11 different cast scanners.

Method And Materials: Dental arch length (AL), intermolar width (IMW), and intercanine width (ICW) of the reference plaster casts were measured using a coordinate measuring machine (Zeiss O-Inspect 422). The master cast was subsequently scanned 37 times using 11 desktop scanners (3Shape R500, 3Shape R700, 3Shape R1000, 3Shape R2000, Medianetx grande, Medianetx colori, DentaCore CS ULTRA, Dentaurum OrthoX, Maestro 3D, Imetric IScan D104i, GC Aadva Lab Scan).

Accuracy of full-arch scans using intraoral and extraoral scanners: an in vitro study using a new method of evaluation.

The aim of this study was to compare the accuracy of six intraoral scanners as regards clinically relevant distances using a new method of evaluation. An additional objective was to compare intraoral scanners with the indirect digitization of model scanners. A resin master model was created by 3D printing and drilled in five places to reflect the following distances: intermolar width (IMW), intercanine width (ICW), and arch length (AL).

Peridental bone changes after orthodontic tooth movement with fixed appliances: A cone-beam computed tomographic study.

Objective: To quantify treatment-related changes in peridental bone height and thickness in orthodontic patients.

Materials And Methods: Cone-beam computed tomographs (CBCTs) of 43 patients (24 female, 19 male; mean age: 25 years, 5 months) who underwent orthodontic treatment with multibracket appliances for at least 1 year were chosen for retrospective evaluation. Dehiscence depth and changes in bone width and tooth inclination were determined for 954 teeth.

Accuracy and efficiency of full-arch digitalization and 3D printing: A comparison between desktop model scanners, an intraoral scanner, a CBCT model scan, and stereolithographic 3D printing.

Objective: The primary objective of this study was to compare the accuracy and time efficiency of an indirect and direct digitalization workflow with that of a three-dimensional (3D) printer in order to identify the most suitable method for orthodontic use.

Method And Materials: A master model was measured with a coordinate measuring instrument. The distances measured were the intercanine width, the intermolar width, and the dental arch length.

Bone thickness of the anterior palate for orthodontic miniscrews.

Objective: To determine the bone thickness in the anterior palate and to test whether there is any dependency between bone thickness and patient's age or gender and whether there is any difference between left and right sides.

Materials And Methods: Cone beam computed tomographic (CBCT) evaluations (n  =  431; 229 females, 202 males) of healthy orthodontic patients aged 9-30 years were selected from the database of the imaging center network Mesantis. In each CBCT image, palatal bone thickness was determined as the median and 2, 4, 6, and 8 mm paramedian bilaterally.

Dehiscence and fenestration in patients with Class I and Class II Division 1 malocclusion assessed with cone-beam computed tomography.

Introduction: The aim of this study was to compare the presence of alveolar defects (dehiscence and fenestration) in patients with Class I and Class II Division 1 malocclusions and different facial types.

Methods: Seventy-nine Class I and 80 Class II patients with no previous orthodontic treatment were evaluated using cone-beam computed tomography. The sample included 4319 teeth.

Cone-beam computed tomography for routine orthodontic treatment planning: a radiation dose evaluation.

Introduction: Because of the advantages and possibilities of cone-beam computed tomography (CBCT), orthodontists use this method routinely for patient assessment. The aim of this study was to compare the radiation doses for conventional panoramic and cephalometric imaging with the doses for 2 different CBCT units and a multi-slice CT unit in orthodontic practice.

Methods: The absorbed organ doses were measured by using an anthropomorphic phantom loaded with thermoluminescent dosimeters at 16 sites related to sensitive organs.

Radiation absorbed in maxillofacial imaging with a new dental computed tomography device.

Objective: The purpose of this investigation was to measure the tissue-absorbed dose and to calculate the effective dose for the NewTom 9000, a new generation of computed tomographic devices designed specifically for dental applications. Comparisons are made with existing reports on dose measurement and effective dose estimates for panoramic examinations and other computed tomographic imaging modalities for dental implants.

Study Design: Thermoluminescent dosimeters were implanted in a tissue-equivalent humanoid phantom at anatomic sites of interest.