Use of High-Frequency Ultrasound for the Correlation of Epithelial Rete Peg Variation.

OBJECTIVE: Rete pegs are projections of the oral epithelium into connective tissue. Their dimensions change during pathological conditions and may correlate with wound-healing status. Non-invasive, high-frequency ultrasound (US) may be able to capture these changes and aid in early detection of histopathological changes. The aim of this preclinical study is to correlate US images with histology and quantify epithelial layers at different tooth sites. METHODS: Sagittal B-mode images of mid-facial and interproximal oral soft tissue sites were recorded in a preclinical minipig model using a linear array in second harmonic mode (12/24 MHz). Histology samples from the same locations were stained (hematoxylin and eosin), digitized and registered with US images. Manual annotations were used to measure distances D1 (thickness of epithelium on histology vs. hyperechoic zone on US) and D2 (sum of epithelial thickness and length of rete pegs on histology vs. sum of hyperechoic and hypoechoic zone on US) to statistically analyze them. RESULTS: Ultrasonic-derived dimensions yielded a mean bias of -0.64 (55% coefficient of variance [COV]: -180 to +180 µm) and -12 µm (39% COV: -260 to +240 µm) for D1 and D2, respectively. Individualized analysis of D1 and D2 by tooth type showed similar tends in the ability to differentiate between epithelium at different tooth locations, on both histology and US. CONCLUSION: Assessing soft tissue dimensions on a sub-millimeter scale using clinical imaging hardware is still a developing area. Future research might open doors for diagnosis of oral pathologies and abnormal wound healing, and may limit false-positive indications for biopsies.

Ultrasonography-Derived Elasticity Estimation of Live Porcine Oral Mucosa.

OBJECTIVES: To investigate the biomechanical properties of porcine oral tissues with in vivo ultrasonography and to compare the difference between oral alveolar mucosa and gingival tissue concerning compressional and tensile mechanical strain. MATERIALS AND METHODS: Sinclair minipigs (6 females and 4 males, 6 to 18 months of age) were anesthetized for ultrasonography. In vivo high-frequency tissue harmonic ultrasound (12/24 MHz) cine-loops were obtained while inducing mechanical tissue stress (0 to 1 N). Post-processing strain analysis was performed in a cardiac speckle tracking software (EchoInsight®). Region of interest (ROI) was placed for gingival and alveolar mucosa tissues for longitudinal (compressional) and tensile strain analyses. A calibrated gel pad was employed to determine the absolute force (pressure) for the measured tissue strain response function. The resulting elasticity data was statistically analyzed using custom Matlab scripts. RESULTS: In total, 38 sonography cine-loops around the third premolars were included in the investigation. The longitudinal strain of alveolar mucosa ε AM L was found to be significantly (P < .05) larger than that of gingiva ε G L . Across the measured force range, ε AM L ~ 1.7 × Îµ G L . Significant differences between alveolar mucosa and gingiva tissues were found for all forces. The tensile strain of the alveolar mucosa ε AM T was found to be ~2 × Îµ G T (on the epithelial surface of the gingiva). Both were statistically significantly different for forces exceeding ~0.08 N. At depth, that is, 500 and 1000 µm below the epithelial surface, the gingiva was found to have less ability to stretch contrary to the alveolar mucosa. Gingival tissue at 500 µm depth has significantly less tensile strain than at its surface and more than at 1000 µm depth. In contrast, the tensile strain of alveolar mucosa is largely independent of depth. CONCLUSION: Ultrasonography can reveal significant differences in oral alveolar mucosal and gingival elastic properties, such as compressional and tensile strain. Under minute forces equivalent to 10 to 40 g, these differences can be observed. As dental ultrasound is a chairside, and noninvasive modality, obtaining real-time images might soon find clinical utility as a new diagnostic tool for the objective and quantitative assessment of periodontal and peri-implant soft tissues in clinical and research realms. As ultrasound is a safe modality with no known bioeffects, longitudinal monitoring of areas of concern would be particularly attractive.

Auto-dentin platelet-rich fibrin matrix is an alternative biomaterial for different augmentation procedures: A retrospective case series report.

OBJECTIVES: Autologous dentin grafts derived from extracted teeth have shown promise as bone graft materials for promoting bone regeneration. This retrospective case series aimed to evaluate clinical, radiographic, and histologic outcomes of using autologous dentin matrices in various bone regeneration procedures. MATERIALS AND METHODS: This case series included 26 eligible patients and encompassed 4 socket preservation cases, 5 cases of guided tissue regeneration, 5 cases of guided bone regeneration (GBR), 10 cases of sinus augmentation procedures, 2 immediate placement implants, and 2 socket shields. Dentin grafts were prepared from extracted teeth, cleaned, and processed. These grafts were combined with platelet-rich fibrin (PRF) to create adhesive dentin matrices, then covered with collagen membranes for simultaneous guided bone augmentation cases. Cone beam computed tomography (CBCT) scans were conducted before surgery and 4 months postoperatively to assess ridge dimensions. Histologic evaluation was performed through bone core biopsies for socket preservation cases at the 4-month mark. RESULTS: A total of 42 implants were placed in 26 patients, with an average follow-up of 32 months. Notably, two implant failures occurred following lateral maxillary sinus augmentation. CBCT scans at the 4-month interval revealed bone coverage over implant platforms in the majority of cases. Histologic analysis from two cases of socket preservation demonstrated dentin granules enveloped by newly formed bone undergoing continuous remodeling. The quantitative histomorphometric assessment revealed a bone area of 42.8 ± 3.56%, a remaining graft area of 19.05 ± 4.58%, and a viable bone of 38.15 ± 7.84%. CONCLUSIONS: The utilization of autologous dentin particles mixed with PRF proved effective as an alternative to conventional bone graft materials in GBR and maxillary sinus augmentation procedures. Larger controlled clinical trials are recommended to further substantiate these findings.

Total Knee Arthroplasty Hospital Costs by Time-Driven Activity-Based Costing: Robotic vs Conventional.

BACKGROUND: Total knee arthroplasty (TKA) represents a major national health expenditure. The last decade has seen a surge in robotic-assisted TKA (roTKA); however, literature on the costs of roTKA as compared to conventional TKA (cTKA) is limited. The purpose of this study was to assess the costs associated with roTKA as compared to cTKA. METHODS: This was a retrospective cohort cost-analysis study of patients undergoing primary, elective roTKA or cTKA from July 2020 to March 2021. Time-driven activity-based costing (TDABC) was used to determine granular costs. Patient demographics, medical/surgical details, and costs were compared. RESULTS: A total of 2058 TKAs were analyzed (1795 cTKAs and 263 roTKAs). roTKA patients were more often male (50.2% vs 42.3%; P = .016), and discharged home (98.5% vs 93.7%; P = .017), and had longer operating room (OR) time (144.6 vs 130.9 minutes; P < .0001), and lower length of stay (LOS) (1.8 vs 2.1 days; P < .0001). roTKA costs were 2.17× greater for supplies excluding implant (P < .0001), 1.18× for total supplies (P < .0001), 1.12× for OR personnel (P < .0001), and 1.05× for total personnel (P = .0001). Implant costs were similar (P = .076), but 0.98× cheaper for post-anesthesia care unit personnel (P = .018) and 0.84× for inpatient personnel (P < .0001). Overall hospital costs for roTKA were 1.10× more than cTKA (P < .0001). CONCLUSION: roTKA had higher total hospital costs than cTKA. Despite a lower LOS, the longer OR time with higher supply and personnel costs resulted in a costlier procedure. Understanding the costs of roTKA is essential when considering the value (ie, outcomes per dollars spent) of this modern technology.

Disruption of essential metal homeostasis in the brain by cadmium and high-fat diet.

Analyses of human cohort data support the roles of cadmium and obesity in the development of several neurocognitive disorders. To explore the effects of cadmium exposure in the brain, mice were subjected to whole life oral cadmium exposure. There were significant increases in cadmium levels with female animals accumulating more metal than males (p < 0.001). Both genders fed a high fat diet showed significant increases in cadmium levels compared to low fat diet fed mice (p < 0.001). Cadmium and high fat diet significantly affected the levels of several essential metals, including magnesium, potassium, chromium, iron, cobalt, copper, zinc and selenium. Additionally, these treatments resulted in increased superoxide levels within the cortex, amygdala and hippocampus. These findings support a model where cadmium and high fat diet affect the levels of redox-active, essential metal homeostasis. This phenomenon may contribute to the underlying mechanism(s) responsible for the development of neurocognitive disorders.