Quality assessment of instructions for authors in dental, oral and maxillofacial journals

Objective: to develop and test inter-observer reproducibility of instructions for authors quality rating (IAQR) tool measuring the quality of instructions for authors at journal level for a possible improvement of editorial guidelines. Material and methods: instructions for authors of 75 dental and maxillofacial surgery journals were assessed by two independent observers using assessment tool inspired from AGREE with 16 questions and 1 to 4 points scale per answer. Two observers evaluated the instructions of authors independently and blind to impact factor of a given journal. Scores obtained from our tool were compared with “journal impact factor 2013”. Results: IAQR presented with an excellent interobserver reproducibility (κ= 0.81) despite a difference in data distribution between observers. There existed a weak positive correlation between IAQR and “journal impact factor 2013”. Conclusions: The IAQR is a reproducible quality assessment tool at the journal level. The IAQR assess the quality of instruction for authors and it is a good starting point for possible improvements of the instructions for authors, especially when it comes to their completeness. Nemesis relevance: 28% of dental and maxillofacial journals might revise their instructions for authors to provide more up-to-date version

Quality assessment of instructions for authors in dental, oral and maxillofacial journals

Objective: to develop and test inter-observer reproducibility of instructions for authors quality rating (IAQR) tool measuring the quality of instructions for authors at journal level for a possible improvement of editorial guidelines. Material and methods: instructions for authors of 75 dental and maxillofacial surgery journals were assessed by two independent observers using assessment tool inspired from AGREE with 16 questions and 1 to 4 points scale per answer. Two observers evaluated the instructions of authors independently and blind to impact factor of a given journal. Scores obtained from our tool were compared with “journal impact factor 2013”. Results: IAQR presented with an excellent interobserver reproducibility (κ= 0.81) despite a difference in data distribution between observers. There existed a weak positive correlation between IAQR and “journal impact factor 2013”. Conclusions: The IAQR is a reproducible quality assessment tool at the journal level. The IAQR assess the quality of instruction for authors and it is a good starting point for possible improvements of the instructions for authors, especially when it comes to their completeness. Nemesis relevance: 28% of dental and maxillofacial journals might revise their instructions for authors to provide more up-to-date versio

Three-dimensional analysis of airway space and mandibular morphology in Pierre Robin sequence using cone beam computed tomography

Objectives: The Pierre Robin sequence (PRS) is defined by retromicrognathia, glossoptosis, and sleep apnea and can also be associated with cleft palate. Diagnosis, management and mandibular catch-up growth are still controversial issues in PRS patients. The aim of our retrospective study was to evaluate in three dimensions (3D) the airway space and mandibular morphology in PRS compared to a normal control group patients in the pre-orthodontic period of life. The null hypothesis was that we would not find a significant difference between the PRS and control group patients in oropharyngeal airway volume measurements. Material and methods: We analyzed 9 PRS patients (mean age: 8 years-old) who underwent cleft palate surgery in the first four months of life, performed by the same surgeon using the same technique. Cone-beam computed tomography (CBCT) was performed in these patients after local ethical committee approval. The control group consisted of 15 patients (mean age: 9 years-old) with CBCT already performed for other reasons. 3D Slicer was used in both groups for semi-automatic segmentation of the airway space. Two independent observers performed semi-automatic segmentations twice in each patient with a one- week interval between the two series of measurements. Airway volume was automatically measured using 3D Slicer. We also developed a 3D cephalometric analysis with Maxilim software in order to define a 3D mandibular morphology which consisted of 25 landmarks, 4 planes, and 23 distances. Two independent observers performed the 3D cephalometric analysis twice for each patient, with a one- week interval between the two series of measurements. Results: There was no significant difference in the intra- and inter-observer measurements between the PRS and control groups for airway space volume (p<0.05). However, there was a significant difference in the shape of the mandible between the PRS group and the control group (p<0.05). Conclusions: Vertical ramus width and mandibular global anteroposterior length were significantly lower in the PRS group. Mandibular hypoplasia could be found in PRS patients not only in the horizontal dimension. Nemesis relevance: the null hypothesis was confirmed. Moreover we failed to find exactly the same control group under 9 years-old due to radioprotection restrictions of application of cone beam CT in children

Validation of a windowing protocol for accurate in vivo tooth segmentation using i-CAT cone beam computed tomography

BACKGROUND: Validation of three-dimensional (3D) reconstructions of full dental arches with crowns and roots based on cone beam computed tomography (CBCT) imaging represents a key issue in 3D digital dentistry. OBJECTIVES: The aim of the study was to search for the most accurate in vivo windowing-based manual tooth segmentation using CBCT. The null hypothesis was that all applied windowing protocols were equivalent in terms of in vivo tooth volume measurement using CBCT. MATERIAL AND METHODS: This retrospective study was based on preoperative CBCT images from patients who underwent further tooth extractions for reasons independent of this study. Written informed consent was obtained from all the participants, and the study was approved by the Ethics Committee of Cliniques Universitaires Saint Luc (Brussels, Belgium). The radiological protocol was I-CAT CBCT, 0.3 mm slice thickness, 8 cm × 16 cm field of view, 120 kVp, and 18 mAs. A total of 36 teeth were extracted from 14 patients between the ages of 18 and 68 years. Using 3D Slicer software, segmentations were performed twice by 2 independent observers, with a 1-month time period between the 2 segmentations to study intraand inter-observer repeatability and reproducibility. Four windowing protocols (level/window) were applied: 1. 1131/1858, 2. 2224/4095, 3. 1131/4095, and 4. AUTO, an automatic protocol provided by default by the software. A total of 576 segmentations were performed. Tooth volumes were automatically calculated using the software. To compare the volumes obtained from CBCT segmentations with a gold-standard method, we laser-scanned the extracted teeth. RESULTS: Excellent intraand inter-observer intraclass correlations were found for all of the protocols used. The best windowing protocol was 1131/1858 for both observers. Tooth volumes were obtained by manual segmentation of the CBCT images and using windowing protocol 1131/1858. No significantly different tooth volumes were found by laser scanning. CONCLUSIONS: Our null hypothesis was rejected. Only windowing protocol 1131/1858 allowed for significantly closer 3D in vivo segmentation of a tooth compared to I-CAT CBCT, with excellent intra-observer repeatability and inter-observer reproducibility

Reproducibility of three-dimensional posterior cranial base angles using low-dose computed tomography

Objectives One of the key aspects of three-dimensional (3D) craniofacial cephalometry is the measurement of posterior cranial base angle as this area is deeply involved in craniofacial development. The purpose of our retrospective study was to define the best reproducible 3D posterior cranial base angles among five 3D angles transposed from 2D cephalometry (Cousin, BL1 of Ross and Ravosa, Bjork, Delaire, CBA4 of Liberman) and seven 3D angles based on physical anthropology studies and on new concepts (R1 to R7). The null hypothesis was that all 3D posterior cranial base angles were equally reproducible. Material and methods We used a preoperative low-dose computed tomography (CT) data from 20 adult patients undergoing orthognathic surgery after approval by local ethical committee. Two independent observers performed two series of 23 3D landmark identifications on 3D CT surface rendering of each patient using Maxilim software. Then, the same observers performed twice 3D cephalometric analyses (23 landmarks, 4 midpoints, 19 planes) that provided the automatic measurement of 12 posterior cranial base angles. Results Inter-observer correlation coefficient varied from 0.545 (Cousin) to 0.695 (CBA4 of Liberman) and from −0.177 (R2) to 0.827 (R4). Conclusions The null hypothesis was rejected. The most reproducible angle was 3D angle R4 based on “basion,” “superior optic” (right, left), and “crista galli inferior” landmarks

Three-dimensional Frankfort horizontal plane for 3D cephalometry: a comparative assessment of conventional versus novel landmarks and horizontal planes

BACKGROUND: To assess the reproducibility of landmarks in three dimensions that determine the Frankfort horizontal plane (FH) as well as two new landmarks, and to evaluate the angular differences of newly introduced planes to the FH. METHODS: Three-dimensional (3D) surface models were created from CBCT scans of 26 dry human skulls. Porion (Po), orbitale (Or), internal acoustic foramen (IAF), and zygomatico-maxillary suture (ZyMS) were indicated in the software by three observers twice with a 4-week interval. Angles between two FHs (FH 1: Or-R, Or-L, mid-Po; FH 2: Po-R, Po-L, mid-Or) and between FHs and new planes (Plane 1-6) were measured. Coordinates were exported to a spreadsheet. A statistical analysis was performed to define the landmark reproducibility and 3D angles. RESULTS: Intra- and inter-observer landmark reproducibility showed mean difference more than 1 mm for x-coordinates of all landmarks except IAF. IAF showed significantly better reproducibility than other landmarks (P < 0.0018). The mean angular difference between FH 1 and FH 2 was 0.7 degrees. Plane 3, connecting Or-R, Or-L and mid-IAF, and Plane 4, connecting Po-R, Po-L and mid-ZyMS, both showed an angular difference of less than 1 degree when compared to FHs. CONCLUSIONS: This study revealed poor reproducibility of the traditional FH landmarks on the x-axis and good reproducibility of a new landmark tested to replace Po, the IAF. Yet, Or showed superior results compared to ZyMS. The potential of using new horizontal planes was demonstrated. Future studies should focus on identification of a valid alternative for Or and ZyMS and on clinical implementation of the findings

Murine models of bone sarcomas

This chapter describes the procedures for inducing bone sarcoma in mice. Two models based on inoculation of cancer cells in paraosseous and intraosseous site will be described. In addition to providing technical aspects of anesthesia and surgical options, key information of cell preparation and postoperative follow-up will be discussed