Feasibility of a Novel Surface-Guided Setup Technique to Reproduce Neck Curvature Using two Regions of Interest.

PURPOSE: To improve the setup reproducibility of neck curvature using real-time optical surface imaging (OSI) guidance on 2 regions of interest (ROIs) to infer cervical spine (c-spine) curvature for surface-guided radiotherapy (SGRT) of head-and-neck (HN) and c-spine cancer. METHODS: A novel SGRT setup approach was designed to reproduce neck curvature with 2 ROIs: upper-chest ROI and open-face ROI. It was hypothesized that the neck curvature could be reproduced if both ROIs were aligned within ±3 mm/2˚ tolerance. This was tested prospectively in 7 volunteers using real-time 3D-OSI guidance and lateral 2D-photography verification after the 3D and 2D references were captured from the initial conventional setup. Real-time SGRT was performed to align chest-ROI and face-ROI, and the longitudinal distance between them was adjustable using a head-support slider. Verification of neck curvature anteriorly and posteriorly was achieved by overlaying edge-extracted lateral pictures. Retrospectively, the relationship between anterior surface and spinal canal alignment was checked in 11 patients using their simulation CT (simCT) and setup cone-beam CT (CBCT). After the anterior surface was rigidly aligned, the spinal canal alignment was checked and quantified using the mean-distance-to-agreement (MDA) and DICE similarity index, and surface-to-spine correlation was calculated. RESULTS: The reproducibility of neck curvatures using the 2xROI SGRT setup is verified and the mean neck-outline-matching difference is within ±2 mm in lateral photographic overlays. The chest-ROI alignment takes 110 ± 58 s and the face-ROI takes 60 ± 35 s. When the anterior body surface is aligned (MDA = 1.1 ± 0.6 mm, DICE = 0.96 ± 0.02,) the internal spinal canal is also aligned (MDA = 1.0 ± 0.3 mm, DICE = 0.84 ± 0.04) in 11 patients. The surface-to-spine correlation is c = 0.90 (MDA) and c = 0.85 (DICE). CONCLUSION: This study demonstrates the feasibility of the novel 2-ROI SGRT setup technique to achieve reproducible neck and c-spine curvature regardless of neck visibility and availability as ROI. Staff training is needed to adopt this unconventional SGRT technique to improve patient setup.

A Simulation-Free Replacement Solution for Radiation Therapy Immobilization Devices Using Computer Numerical Control (CNC) -Milled Polystyrene Molds.

Purpose: In radiation therapy (RT), if an immobilization device is lost or damaged, the patient may need to be brought back for resimulation, device fabrication, and treatment planning, causing additional imaging radiation exposure, inconvenience, cost, and delay. We describe a simulation-free method for replacing lost or damaged RT immobilization devices. Methods and Materials: Replacement immobilization devices were fabricated using existing simulation scans as design templates by computer numerical control (CNC) milling of molds made from extruded polystyrene (XPS). XPS material attenuation and bolusing properties were evaluated, a standard workflow was established, and 12 patients were treated. Setup reproducibility was analyzed postfacto using Dice similarity coefficient (DSC) and mean distance to agreement (MDA) calculations comparing onboard treatment imaging with computed tomography (CT) simulations. Results: Results showed that XPS foam material had less dosimetric impact (attenuation and bolusing) than materials used for our standard immobilization devices. The average direct cost to produce each replacement mold was $242.17, compared with over $2000 for standard resimulation. Hands-on time to manufacture was 86.3 minutes, whereas molds were delivered in as little as 4 hours and mostly within 24 hours, compared with a week or more required for standard resimulation. Each mold was optically scanned after production and was measured to be within 2-mm tolerance (pointwise displacement) of design input. All patients were successfully treated using the CNC-milled foam mold replacements, and pretreatment imaging verified satisfactory clinical setup reproduction for each case. The external body contours from the setup cone beam CT and the original CT simulation with matching superior-inferior extent were compared by calculating the DSC and MDA. DSC average was 0.966 (SD, 0.011), and MDA average was 2.694 mm (SD, 0.986). Conclusions: CNC milling of XPS foam is a quicker and more convenient solution than traditional resimulation for replacing lost or damaged RT immobilization devices. Satisfactory patient immobilization, low dosimetric impact compared with standard immobilization devices, and strong correlation of onboard contours with CT simulations are shown. We share our clinical experience, workflow, and manufacturing guide to help other clinicians who may want to adopt this solution.

Pulp Survival of Cracked Teeth with Reversible Pulpitis after Orthodontic Banding and Coronal Coverage - A Prospective Cohort Study with One Year Follow Up.

INTRODUCTION: The aim of this prospective study was to investigate the 1-year pulp survival of cracked teeth with reversible pulpitis managed with initial stabilization using orthodontic bands, followed by coronal coverage restorations. METHODS: One-hundred-and-twenty-five patients with a cracked tooth with reversible pulpitis each were recruited. Preoperative patient and tooth data were collected. After definitive pulp diagnoses were determined following an interim period of orthodontic banding, coronal coverage restorations were placed. Cox and logistic regression analyses were used to assess possible prognostic factors and to correlate initial time to pulp stabilization while in orthodontic bands with eventual outcome. Pulp survival was determined using both clinical and radiographic findings. RESULTS: One-hundred-and-six cracked teeth were followed up at 1 year. Pulp survival based on clinical and radiographic findings was found in 81 teeth (76.4%). Out of 25 failures, 11 (44%) required root canal treatment (RCT) in the orthodontic band stage and 10 (40%) required RCT during the process of or after coronal coverage restorations. Four teeth (16%) had incidental findings of periapical radiolucencies at the 1-year review without clinical symptoms. Teeth requiring RCT were found to have required longer periods in orthodontic bands prior to a definitive pulp diagnosis (P < .05). CONCLUSION: A step-by-step approach by using orthodontic banding to monitor pulp status may reduce the incidence of RCT required through definitive coronal coverage restorations for cracked teeth with reversible pulpitis.

Knowledge of undergraduate and postgraduate dental students about managing traumatic dental injuries based on the 2020 International Association of Dental Traumatology guidelines: A online survey of 10 dental schools from 10 countries.

BACKGROUND/AIM: The knowledge of dental students about managing traumatic dental injuries (TDIs) may not be uniform, depending on global location and dental education. The aim of this study was to evaluate the level of knowledge of undergraduate and postgraduate students specializing in endodontics and pediatric dentistry at 10 dental schools in 10 countries about the 2020 International Association of Dental Traumatology (IADT) guidelines regarding the management of TDIs. MATERIALS & METHODS: A previously published questionnaire was used in the current survey. It was an online survey with 12 questions regarding the management of TDIs and some additional questions regarding sociodemographic and professional profiles of the participants were added. The survey was distributed to final-year undergraduate students and postgraduate students in pediatric dentistry and endodontics from 10 dental schools. Simple frequency distributions and descriptive statistics were predominantly used to describe the data. Differences in the median percentage scores among the student categories were assessed using the Kruskal-Wallis test followed by Dwass-Steel-Critchlow-Fligner pairwise comparisons. RESULTS: A total of 347 undergraduates, 126 postgraduates in endodontics, and 72 postgraduates in pediatric dentistry from 10 dental schools participated in this survey. The postgraduates had a significantly higher percentage score for correct responses compared with the undergraduates. No significant difference was observed between the endodontic and pediatric dentistry postgraduates. CONCLUSION: The knowledge possessed by undergraduate and postgraduate students concerning the IADT-recommended management of TDIs varied across the globe and some aspects were found to be deficient. This study emphasizes the critical importance of reassessing the teaching and learning activities pertaining to the management of TDIs.

Generation of Induced Pluripotent Stem Cell-Derived iTenocytes via Combined Scleraxis Overexpression and 2D Uniaxial Tension.

Today's challenges in tendon and ligament repair necessitate the identification of a suitable and effective candidate for cell-based therapy to promote tendon regeneration. Mesenchymal stromal cells (MSCs) have been explored as a potential tissue engineering strategy for tendon repair. While they are multipotent and have regenerative potential in vivo, they are limited in their self-renewal capacity and exhibit phenotypic heterogeneity. Induced pluripotent stem cells (iPSCs) can circumvent these limitations due to their high self-renewal capacity and unparalleled developmental plasticity. In tenocyte development, Scleraxis (Scx) is a crucial direct molecular regulator of tendon differentiation. Additionally, mechanoregulation has been shown to be a central element guiding embryonic tendon development and healing. As such, we have developed a protocol to encapsulate the synergistic effect of biological and mechanical stimulation that may be essential for generating tenocytes. iPSCs were induced to become mesenchymal stromal cells (iMSCs) and were characterized with classic mesenchymal stromal cell markers via flow cytometry. Next, using a lentiviral vector, the iMSCs were transduced to stably overexpress SCX (iMSCSCX+). These iMSCSCX+ cells can be further matured into iTenocytes via uniaxial tensile loading using a 2D bioreactor. The resulting cells were characterized by observing the upregulation of early and late tendon markers, as well as collagen deposition. This method of generating iTenocytes can be used to assist researchers in developing a potentially unlimited off-the-shelf allogeneic cell source for tendon cell therapy applications.

Phase-sensitive deep reconstruction method for rapid multiparametric MR fingerprinting and quantitative susceptibility mapping in the brain.

INTRODUCTION: This study explores the potential of Magnetic Resonance Fingerprinting (MRF) with a novel Phase-Sensitivity Deep Reconstruction Network (PS-DRONE) for simultaneous quantification of T1, T2, Proton Density, B1+, phase and quantitative susceptibility mapping (QSM). METHODS: Data were acquired at 3 T in vitro and in vivo using an optimized EPI-based MRF sequence. Phantom experiments were conducted using a standardized phantom for T1 and T2 maps and a custom-made agar-based gadolinium phantom for B1 and QSM maps. In vivo experiments included five healthy volunteers and one patient diagnosed with brain metastasis. PSDRONE maps were compared to reference maps obtained through standard imaging sequences. RESULTS: Total scan time was 2 min for 32 slices and a resolution of [1 mm, 1 mm, 4.5 mm]. The reconstruction of T1, T2, Proton Density, B1+ and phase maps were reconstructed within 1 s. In the phantoms, PS-DRONE analysis presented accurate and strongly correlated T1 and T2 maps (r = 0.99) compared to the reference maps. B1 maps from PS-DRONE showed slightly higher values, though still correlated (r = 0.6) with the reference. QSM values showed a small bias but were strongly correlated (r = 0.99) with reference data. In the in vivo analysis, PS-DRONE-derived T1 and T2 values for gray and white matter matched reference values in healthy volunteers. PS-DRONE B1 and QSM maps showed strong correlations with reference values. CONCLUSION: The PS-DRONE network enables concurrent acquisition of T1, T2, PD, B1+, phase and QSM maps, within 2 min of acquisition time and 1 s of reconstruction time.

A video-based decision aid improved knowledge and decreased decisional conflict for asymptomatic persistent endodontic lesions.

AIM: This prospective cohort study aimed to (i) evaluate patients' treatment decisions, decisional conflict and knowledge levels before and after use of a video-based decision aid (DA) on asymptomatic persistent endodontic lesions (APEL) and to (ii) elicit important decision factors for patients in the decision-making process. METHODOLOGY: A video DA modelled after the International Patient Decision Aids Standards (IPDAS) was designed. The video was pilot-tested, revised and used on 50 patients referred to the graduate endodontic clinic and presenting with an incidental finding of APEL detected on radiographs, with informed consent (DSRB 2020/00133). Recruitment was conducted from June 2020 to November 2021. Patients' treatment decisions and decision-making process were studied. Patients also completed a questionnaire on knowledge gain, decisional conflict and confidence levels. RESULTS: Forty-three patients (48 teeth) out of 50 patients chose long-term monitoring of APEL while 7 patients (7 teeth) decided on endodontic intervention. Median knowledge scores increased from 58.3 (IQR: 41.7, 75.0) to 87.5 (IQR: 75.0, 100.0) (p < .001); median decisional conflict scale (DCS) scores decreased from 25.0 (IQR: 12.5, 34.4) to 3.1 (IQR: 0, 23.8) (p < .001), and 44 (88%) patients were confident or very confident with their treatment decisions. Statistical analyses showed that asymptomatic condition of tooth was the sole decision factor with statistical significance while socioeconomic factors (age, gender, race, education and income levels) showed no significant trend. CONCLUSIONS: The majority of patients presenting with APEL in this study chose long-term monitoring over immediate intervention. Using the video-based DA in the decision-making process significantly improved patients' knowledge and decreased their decisional conflict levels.

The Use of Magnetic Resonance Imaging in Radiation Therapy Treatment Simulation and Planning.

Ever since its introduction as a diagnostic imaging tool the potential of magnetic resonance imaging (MRI) in radiation therapy (RT) treatment simulation and planning has been recognized. Recent technical advances have addressed many of the impediments to use of this technology and as a result have resulted in rapid and growing adoption of MRI in RT. The purpose of this article is to provide a broad review of the multiple uses of MR in the RT treatment simulation and planning process, identify several of the most used clinical scenarios in which MR is integral to the simulation and planning process, highlight existing limitations and provide multiple unmet needs thereby highlighting opportunities for the diagnostic MR imaging community to contribute and collaborate with our oncology colleagues. EVIDENCE LEVEL: 5 TECHNICAL EFFICACY: Stage 5.

Prevalence of Comprehensive Eye Examination in Preschool Children With Eye Conditions.

Introduction: The purpose of this study is to assess the prevalence of comprehensive eye examinations in multiethnic preschool children, including children with visually significant eye conditions, and identify factors associated with comprehensive eye examinations. Methods: A sample of 9,197 African American, Hispanic, Asian American, and non-Hispanic White children aged 6-72 months was recruited for the Multi-Ethnic Pediatric Eye Disease Study from 2003 to 2011. Logistic regression performed in 2022 identified independent factors associated with parent-reported history of comprehensive eye examinations. The proportion of children with previous comprehensive eye examinations and the proportion with undetected amblyopia or strabismus were measured. Results: The prevalence of comprehensive eye examinations was 6.3% overall and 38.3%, 24.8%, 19.1%, 15.1%, and 9.8% among children with strabismus, amblyopia, significant anisometropia, hyperopia, and astigmatism, respectively. Children without prior comprehensive eye examinations were more likely to have undetected amblyopia or strabismus than those with comprehensive eye examination history (ps<0.001). The prevalence of comprehensive eye examinations was higher among older children. Prevalence varied by race/ethnicity, with 8.1%, 7.9%, 6.3%, and 4.9% of non-Hispanic White, Asian American, African American, and Hispanic children having had prior comprehensive eye examinations, respectively; however, the differences did not remain after adjusting for other associated factors. Older age, a primary caregiver with a college/university degree or higher, having vision insurance, gestational age <33 weeks, neurodevelopmental disorder diagnosis, strabismus, and ocular disease history were all statistically significantly associated with a relatively higher prevalence of comprehensive eye examinations in multivariable analyses. Conclusions: Comprehensive eye examinations were uncommon among preschool children, including those with treatable vision disorders. Interventions, such as parent education and vision insurance, are needed to imaprove comprehensive eye examination access and utilization for at-risk preschool children.

Experimental Modeling of Host-Bacterial Interactions in Head and Neck Squamous Cell Carcinoma.

The microscopic species colonizing the human body, collectively referred to as the microbiome, play a crucial role in the maintenance of tissue homeostasis, immunity, and the development of disease. There is evidence to suggest associations between alterations in the microbiome and the development of head and neck squamous cell carcinomas (HNSCC). The use of two-dimensional (2D) modeling systems has made significant strides in uncovering the role of microbes in carcinogenesis; however, direct mechanistic links remain in their infancy. Patient-derived three-dimensional (3D) HNSCC organoid and organotypic models have recently been described. Compared to 2D models, 3D organoid culture systems effectively capture the genetic and epigenetic features of parent tissue in a patient-specific manner and may offer a more nuanced understanding of the role of host-microbe responses in carcinogenesis. This review provides a topical literature review assessing the current state of the field investigating the role of the microbiome in HNSCC; including in vivo and in vitro modeling methods that may be used to characterize microbiome-epithelial interactions.

Prolonged operative time predicts postoperative deep venous thrombosis in head and neck cancer patients who undergo free flap reconstruction.

Objective: This study sought to quantify the deep venous thrombosis (DVT) incidence in head and neck cancer (HNC) patients undergoing free tissue transfer and to identify independent predictors of postoperative DVT. Materials and Methods: This is a cross-sectional study of the National Surgical Quality Improvement Program database from 2010 through 2020. The sample included all HNC surgical patients treated with free flap reconstruction. The study outcome was the presence of a DVT requiring treatment within 30 days of surgery. Univariate analyses were performed using chi-squared and independent t-tests. A multiple logistic regression model was created using all significant univariate predictors. Results: A total of 3954 patients were identified, of whom 53 (1.3%) experienced a postoperative DVT. The only medical comorbidity associated with DVT was COPD (RR = 2.7 [1.3, 5.4]; p < .01). Operative time longer than 9 hours (RR = 1.9 [1.0, 3.2]; p = .04) and length of stay longer than 10 days (RR = 1.9 [1.1, 3.2]; p = .02) were associated with greater DVT rates. In the multivariate analysis, only COPD (p < .01) and operative time (p = .02) were independently associated with DVT risk. The presence of a DVT was found to increase the relative risk of readmission (RR = 2.1 [1.2, 3.6]; p < .01) and non-home disposition (RR = 2.4 [1.7, 3.5]; p < .01). Conclusions: The incidence of DVT in HNC free flap patients was comparable to what has been reported in the general population of HNC surgery patients. Operative time >9 h and COPD history were independent risk factors for DVT in this subset of patients. Symptomatic DVTs necessitating treatment were accompanied by poorer post-hospitalization outcomes. Level of Evidence: Level 3.

Specimen Shape and Elution Time Affect the Mineralization and Differentiation Potential of Dental Pulp Stem Cells to Biodentine.

The liquid extract method is commonly used to evaluate the cytotoxicity and bioactivity of materials. Although ISO has recommended guidelines for test methods, variations in elution period, and shape of samples can influence the biological outcomes. The aim of this study was to investigate the influence of material form and elution period of Biodentine on dental pulp stem cells (DPSCs)' proliferation and mineralization. Biodentine (0.2 g) discs or powder were immersed in culture media (10 mL) for 1, 3 or 7 days (D1, D3 and D7). The eluents were filtered and used to treat DPSC. The calcium release profile and pH were determined. Cell proliferation was evaluated by MTS for 3 days, and mineralization and differentiation were assessed by alizarin red S staining (Ca2+/ng of DNA) and qRT-PCR (MEPE, DSPP, DMP-1, RUNX2, COL-I and OCN) for 14 days. Statistical analysis was performed with a one or two-way ANOVA and post hoc Tukey's test (pH, calcium release and proliferation) or Mann-Whitney test (α = 0.05). pH and calcium ion release of powdered eluents were significantly higher than disc eluents. Powdered eluent promoted extensive cell death, while the disc form was cytocompatible. All disc eluents significantly increased the gene expression and mineralization after 14 days compared to the untreated control. D7 induced less mineralization and differentiation compared to D1 and D3. Thus, the materials' form and elution time are critical aspects to be considered when evaluating the bioactivity of materials, since this binomial can affect positively and negatively the biological outcomes.