Factors Associated With Dental Caries: Differential Experiences Among Incarcerated Individuals in Scotland.

Incarcerated individuals experience poorer health, including dental health, when compared with the general population. Although interventions that target multiple determinants of health are more effective, there are limited investigations of the determinants of dental health, and how these differ, among incarcerated individuals. This article describes a secondary data analysis to investigate caries (dental decay) experience and associated risk indicators from a survey of females, adult males, and young males incarcerated in Scotland. Substance misuse significantly explained caries risk for adults, and tailored interventions are warranted to address smoking and dental attitudes among females, and for adult males housing support alongside oral health education are indicated.

Development of a Root Caries Prediction Model in a Population of Dental Attenders.

Root caries prevalence is increasing as populations age and retain more of their natural dentition. However, there is generally no accepted practice to identify individuals at risk of disease. There is a need for the development of a root caries prediction model to support clinicians to guide targeted prevention strategies. The aim of this study was to develop a prediction model for root caries in a population of regular dental attenders. Clinical and patient-reported predictors were collected at baseline by routine clinical examination and patient questionnaires. Clinical examinations were conducted at the 4-year timepoint by trained outcome assessors blind to baseline data to record root caries data at two thresholds - root caries present on any teeth (RC > 0) and root caries present on three or more teeth (RC ≥ 3). Multiple logistic regression analyses were performed with the number of participants with root caries at each outcome threshold utilized as the outcome and baseline predictors as the candidate predictors. An automatic backwards elimination process was conducted to select predictors for the final model at each threshold. The sensitivity, specificity, and c-statistic of each model's performance was assessed. A total of 1,432 patient participants were included within this prediction model, with 324 (22.6%) presenting with at least one root caries lesion, and 97 (6.8%) with lesions on three or more teeth. The final prediction model at the RC >0 threshold included increasing age, having ≥9 restored teeth at baseline, smoking, lack of knowledge of spitting toothpaste without rinsing following toothbrushing, decreasing dental anxiety, and worsening OHRQoL. The model sensitivity was 71.4%, specificity 69.5%, and c-statistic 0.79 (95% CI: 0.76, 0.81). The predictors included in the final prediction model at the RC ≥ 3 threshold included increasing age, smoking, and lack of knowledge of spitting toothpaste without rinsing following toothbrushing. The model sensitivity was 76.5%, specificity 73.6%, and c-statistic 0.81 (95% CI: 0.77, 0.86). To the authors' knowledge, this is the largest published root caries prediction model, with statistics indicating good model fit and providing confidence in its robustness. The performance of the risk model indicates that adults at risk of developing root caries can be accurately identified, with superior performance in the identification of adults at risk of multiple lesions.

Guiding the Prostatic Artery Embolization Procedure With Computational Fluid Dynamics.

Benign prostatic hyperplasia (BPH) is a common disease associated with lower urinary tract symptoms and is the most frequent benign tumor in men. To reduce BPH therapy complications, prostatic artery embolization (PAE) was developed to replace the surgical options. PAE is a minimally invasive technique in which emboli are injected into the prostate arteries (PA), obstructing the blood flow in the hypervascular nodules. In this work, a personalized PAE treatment strategy was proposed using patient-specific computational fluid dynamics (CFD). First, the hemodynamics environment in the iliac arterial tree considering a large network of bifurcations was studied. The results showed complex blood flow patterns in the iliac arterial network. Subsequently, the transport of embolic particulates during PAE for the standard horizontal and hypothetical vertical patient positioning was simulated using Lagrangian particle tracking. Emboli of different sizes were released at various locations across the iliac arterial tree. The emboli entering the PA were mapped back to their initial location to create emboli release maps (ERMs). The obtained ERMs during the standard patient positioning for smaller emboli at certain release locations showed distinct regions in which if the emboli were released within these regions, all of them would reach the PA without nontarget embolization. During the hypothetical vertical patient positioning, the larger emboli formed a larger coherent region in the ERMs. Our patient-specific model can be used to find the best spatial location for emboli injection and perform the embolization procedure with minimal off-target delivery.

Three-dimensional printing CT-derived objects with controllable radiopacity.

PURPOSE: The goal of this work was to develop phantoms for the optimization of pre-operative computed tomography (CT) scans of the prostate artery, which are used for embolization planning. METHODS: Acrylonitrile butadiene styrene (ABS) pellets were doped with barium sulfate and extruded into filaments suitable for 3D printing on a fused deposition modeling (FDM) printer. Cylinder phantoms were created to evaluate radiopacity as a function of doping percentage. Small-diameter tree phantoms were created to assess their composition and dimensional accuracy. A half-pelvis phantom was created using clinical CT images, to assess the printer's control over cortical bone thickness and cancellous bone attenuation. CT-derived prostate artery phantoms were created to simulate complex, contrast-filled arteries. RESULTS: A linear relationship (R = 0.998) was observed between barium sulfate added (0%-10% by weight), and radiopacity (-31 to 1454 Hounsfield Units [HU]). Micro-CT scans showed even distribution of the particles, with air pockets comprising 0.36% by volume. The small vessels were found to be oversized by a consistent amount of 0.08 mm. Micro-CT scans revealed that the phantoms' interiors were completely filled in. The maximum HU values of cortical bone in the phantom were lower than that of the filament, a result of CT image reconstruction. Creation of cancellous bone regions with lower HU values, using the printer's infill parameter, was successful. Direct volume renderings of the pelvis and prostate artery were similar to the clinical CT, with the exception that the surfaces of the phantom objects were not as smooth. CONCLUSIONS: It is possible to reliably create FDM 3D printer filaments with predictable radiopacity in a wide range of attenuation values, which can be used to print dimensionally accurate radiopaque objects derived from CT data. Phantoms of this type can be quickly and inexpensively developed to assess and optimize CT protocols for specific clinical applications.

Cryogel scaffolds from patient-specific 3D-printed molds for personalized tissue-engineered bone regeneration in pediatric cleft-craniofacial defects.

Bone defects are extremely common in children with cleft-craniofacial conditions, especially those with alveolar cleft defects and cranial defects. This study used patient-specific 3D-printed molds derived from computed tomography and cryogel scaffold fabrication as a proof of concept for the creation of site-specific implants for bone reconstruction. Cryogel scaffolds are unique tissue-engineered constructs formed at sub-zero temperatures. When thawed, the resulting structure is macroporous, sponge-like, and mechanically durable. Due to these unique properties, cryogels have excellent potential for the treatment of patient-specific bone defects; however, there is little literature on their use in cleft-craniofacial defects. While 3D-printing technology currently lacks the spatial resolution to print the microstructure necessary for bone regeneration, it can be used to create site-specific molds. Thus, it is ideal to integrate these techniques for the fabrication of scaffolds with patient-specific geometry. Overall, all cryogels possessed appropriate geometry to allow for cell infiltration after 28 days. Additionally, suitable mechanical durability was demonstrated where, despite mold geometry, all cryogels could be compressed without exhibiting crack propagation. Such a patient-specific scaffold would be ideal in pediatric cleft-craniofacial defects, as these are complex 3D defects and children have less donor bone availability.

C-arm cone beam computed tomography needle path overlay for fluoroscopic guided vertebroplasty.

STUDY DESIGN: Retrospective review. OBJECTIVE: To report our early clinical experience using C-arm cone beam computed tomography (C-arm CBCT) with fluoroscopic overlay for needle guidance during vertebroplasty. SUMMARY OF BACKGROUND DATA: C-arm CBCT is advanced three-dimensional (3-D) imaging technology that is currently available on state-of-the-art flat panel based angiography systems. The imaging information provided by C-arm CBCT allows for the acquisition and reconstruction of "CT-like" images in flat panel based angiography/interventional suites. As part of the evolution of this technology, enhancements allowing the overlay of cross-sectional imaging information can now be integrated with real time fluoroscopy. We report our early clinical experience with C-arm CBCT with fluoroscopic overlay for needle guidance during vertebroplasty. METHODS: This is a retrospective review of 10 consecutive oncology patients who underwent vertebroplasty of 13 vertebral levels using C-arm CBCT with fluoroscopic overlay for needle guidance from November 2007 to December 2008. Procedural data including vertebral level, approach (transpedicular vs. extrapedicular), access (bilateral vs. unilateral) and complications were recorded. Technical success with the overlay technology was assessed based on accuracy which consisted of 4 measured parameters: distance from target to needle tip, distance from planned path to needle tip, distance from midline to needle tip, and distance from the anterior 1/3 of the vertebral body to needle tip. Success within each parameter required that the distance between the needle tip and parameter being evaluated be no more than 5 mm on multiplanar CBCT or fluoroscopy. RESULTS: Imaging data for 12 vertebral levels was available for review. All vertebral levels were treated using unilateral access and 9 levels were treated with an extrapedicular approach. Technical success rates were 92% for both distance from planned path and distance from midline to final needle tip, 100% when distance from needle tip to the anterior 1/3 border of the vertebral body was measured, and 75% when distance from target to needle tip was measured. There were no major complications. Minor complications consisted of 3 cases (25%) of cement extravasation. CONCLUSION: C-arm CBCT with needle path overlay for fluoroscopic guided vertebroplasty is feasible and allows for reliable unilateral therapy of both lumbar and thoracic vertebral bodies. Extrapedicular approaches were performed safely and with good accuracy of reaching the targets.