Artificial intelligence in the diagnosis of dental diseases on panoramic radiographs: a preliminary study.

BACKGROUND: Artificial intelligence (AI) has been introduced to interpret the panoramic radiographs (PRs). The aim of this study was to develop an AI framework to diagnose multiple dental diseases on PRs, and to initially evaluate its performance. METHODS: The AI framework was developed based on 2 deep convolutional neural networks (CNNs), BDU-Net and nnU-Net. 1996 PRs were used for training. Diagnostic evaluation was performed on a separate evaluation dataset including 282 PRs. Sensitivity, specificity, Youden's index, the area under the curve (AUC), and diagnostic time were calculated. Dentists with 3 different levels of seniority (H: high, M: medium, L: low) diagnosed the same evaluation dataset independently. Mann-Whitney U test and Delong test were conducted for statistical analysis (ɑ=0.05). RESULTS: Sensitivity, specificity, and Youden's index of the framework for diagnosing 5 diseases were 0.964, 0.996, 0.960 (impacted teeth), 0.953, 0.998, 0.951 (full crowns), 0.871, 0.999, 0.870 (residual roots), 0.885, 0.994, 0.879 (missing teeth), and 0.554, 0.990, 0.544 (caries), respectively. AUC of the framework for the diseases were 0.980 (95%CI: 0.976-0.983, impacted teeth), 0.975 (95%CI: 0.972-0.978, full crowns), and 0.935 (95%CI: 0.929-0.940, residual roots), 0.939 (95%CI: 0.934-0.944, missing teeth), and 0.772 (95%CI: 0.764-0.781, caries), respectively. AUC of the AI framework was comparable to that of all dentists in diagnosing residual roots (p > 0.05), and its AUC values were similar to (p > 0.05) or better than (p < 0.05) that of M-level dentists for diagnosing 5 diseases. But AUC of the framework was statistically lower than some of H-level dentists for diagnosing impacted teeth, missing teeth, and caries (p < 0.05). The mean diagnostic time of the framework was significantly shorter than that of all dentists (p < 0.001). CONCLUSIONS: The AI framework based on BDU-Net and nnU-Net demonstrated high specificity on diagnosing impacted teeth, full crowns, missing teeth, residual roots, and caries with high efficiency. The clinical feasibility of AI framework was preliminary verified since its performance was similar to or even better than the dentists with 3-10 years of experience. However, the AI framework for caries diagnosis should be improved.

pH-responsive aminotriazole doped metal organic frameworks nanoplatform enables self-boosting reactive oxygen species generation through regulating the activity of catalase for targeted chemo/chemodynamic combination therapy.

The rational integration of chemotherapy and hydroxyl radical (·OH)-mediated chemodynamic therapy (CDT) via functional metal-organic frameworks (MOF) carriers has great potential in cancer therapy. In this work, aminotriazole (3-AT) doped polyhedral metal organic frameworks (denoted as MAF) were prepared by template ligand replacement, where CDT was initiated by Cu2+/Cu+ modulated Fenton reaction and enhanced by effectively regulating the catalase activity with 3-AT. However, a rod-like Cu-MOF with 3-AT served as a ligand was obtained by the hydrothermal method without using template. In contrast to Cu-MOF, pH-responsive MAF was chosen as the carrier for targeted drug delivery due to its higher drug load of 17.6% and relatively uniform size, where doxorubicin (DOX) as a model drug was loaded in its cavity and hyaluronic acid (HA) was coated on its surface via electrostatic interactions (denoted as HA-MAF@DOX). In vitro experiments demonstrated that HA-MAF@DOX had high transport efficiency of DOX, effective regulation of catalase (CAT) activity and enhanced cytotoxicity to HepG2 cells. This work is the first use of enzyme inhibitors as ligands to construct functional MOFs via template ligand replacement for effective regulating enzyme activity, mediating intracellular redox homeostasis and enhancing CDT efficacy, which provides a feasible strategy for the construction the functional MOFs in cancer therapy.

Computer-designed surgical templates improve the extraction of impacted supernumerary teeth in the hard palate.

OBJECTIVES: The surgical procedure of bony impacted supernumerary teeth (SNT) in hard palate is commonly done with poor visualization and uncomfortable posture. This study aims to introduce our primary practice of presurgical evaluation and guiding exodontia of bony impacted supernumerary teeth (SNT) in the hard palate to reduce surgical trauma, duration and uncertainty. STUDY DESIGN: Twelve patients with impacted supernumerary teeth in hard palate were included. Intraoral scan and the three-dimensional (3D) reconstruction of the cone beam computed tomography (CBCT) file was superimposed, and virtual simulation of flap elevation and osteotomy was conducted on the rebuilt 3D model. A couple of surgical templates were designed with surgical planning software Mimics, fabricated by a 3D printer and were used to guide the extraction of the impacted SNT. RESULTS: The surgical templates fitted well to the teeth and operation site. All the impacted SNTs were accurately located and extracted without damaging the adjacent vital anatomical structures. All patients had an uneventful postoperative recovery without infection or sensory disturbance. CONCLUSIONS: The application of 3D printed surgical templates reduced trauma and increased the accuracy and predictability of surgical extraction of bony impacted SNT in hard palate. The results of this study increased the accuracy and predictability of surgical extraction of bony impacted SNT in hard palate, and reduced the surgeon's embarrassment and surgical trauma because of location difficulty.

A Supramolecular Photosensitizer System Based on Nano-Cu/ZIF-8 Capped with Water-Soluble Pillar[6]arene and Methylene Blue Host-Guest Complexations.

Photodynamic therapy (PDT) as a safe, non-invasive modality for cancer therapy, in which the low oxygen and high glutathione in the tumor microenvironment reduces therapeutic efficiency. In order to overcome these problems, we prepared a supramolecular photosensitive system of O2-Cu/ZIF-8@ZIF-8@WP6-MB (OCZWM), which was loaded with oxygen to increase the oxygen concentration in the tumor microenvironment, and the Cu2+ in the system reacted with glutathione (GSH) to reduce the GSH concentration to generate Cu+. It is worth noting that the generated Cu+ can produce the Fenton reaction, thus realizing the combination therapy of PDT and chemodynamic therapy (CDT) to achieve the purpose of significantly improving the anti-cancer efficiency.

Lycium ruthenicum Murr. alleviates nonalcoholic fatty liver in mice.

Oxidative stress and inflammation contribute to hypertriglyceridemia-induced nonalcoholic fatty liver disease (NAFLD). Cholesterol-enriched diets increase the risk of NAFLD. Lycium ruthenium Murr. (LRM) contains water-soluble antioxidant proanthocyanidins. Whether Lycium ruthenium Murr. improves NAFLD remains elusive. In this study, we established a model of NAFLD-induced by cholesterol-enriched high-fat diet (western diet) in ApoE -/- mice; oxidative stress and inflammation were examined and intervened by supplement of Lycium ruthenium Murr. (LRM) extracts. LRM supplement did not influence body weight gain, food intake, and lipotoxicity of mice. LRM supplement significantly alleviated triglyceride accumulation in liver, with reduced inflammation, elevated GSH-Px activity, and reduced MDA levels. The expression of fatty acids oxidative gene Scd1 was significantly increased, and fatty acids synthesis-related gene Pparγ was dramatically downregulated on mRNA level in liver of mice with LRM supplement. These data demonstrated that LRM supplement decreased ROS production and inflammation, increased fatty acids oxidation, and reduced fatty acids synthesis in liver, leading to ameliorate the development of NAFLD induced by high western diet. Thus, oxidative stress and inflammation also are involved in the pathogenesis of western diet-induced NAFLD, which is independent of obesity.

Ilex latifolia Thunb protects mice from HFD-induced body weight gain.

Kuding tea is implicated in alleviating metabolic disorders in traditional Chinese medicine. However, the role of Ilex latifolia Thunb (kuding tea), one of the large leaf kuding tea species, in the prevention of the development of obesity remains to be determined. We show here that 7-week-old male mice treated with an Ilex latifolia Thunb supplement for 14 weeks were resistant to HFD-induced body weight gain and hepatic steatosis, accompanied by improved insulin sensitivity. Ilex latifolia Thunb supplementation dramatically reduced the systemic and tissue inflammation levels of mice via reducing pro-inflammatory cytokine levels, increasing anti-inflammatory cytokine levels in the circulation and inhibiting p38 MAPK and p65 NF-κB signaling in adipose tissue. Together, these results indicate that Ilex latifolia Thunb protects mice from the development of obesity and is a potential compound pool for the development of novel anti-obesity drugs.

Seasonal responses of soil respiration to warming and nitrogen addition in a semi-arid alfalfa-pasture of the Loess Plateau, China.

Responses of soil respiration (Rs) to increasing nitrogen (N) deposition and warming will have far-reaching influences on global carbon (C) cycling. However, the seasonal (growing and non-growing seasons) difference of Rs responses to warming and N deposition has rarely been investigated. We conducted a field manipulative experiment in a semi-arid alfalfa-pasture of northwest China to evaluate the response of Rs to nitrogen addition and warming from March 2014 to March 2016. Open-top chambers were used to elevate temperature and N was enriched at a rate of 4.42g m-2yr-1 with NH4NO3. Results showed that (1) N addition increased Rs by 14% over the two-year period; and (2) warming stimulated Rs by 15% in the non-growing season, while inhibited it by 5% in the growing season, which can be explained by decreased plant coverage and soil water. The main effect of N addition did not change with time, but that of warming changed with time, with the stronger inhibition observed in the dry year. When N addition and warming were combined, an antagonistic effect was observed in the growing season, whereas a synergism was observed in the non-growing season. Overall, warming and N addition did not affect the Q10 values over the two-year period, but these treatments significantly increased the Q10 values in the growing season compared with the control treatment. In comparison, combined warming and nitrogen addition significantly reduced the Q10 values compared with the single factor treatment. These results suggest that the negative indirect effect of warming-induced water stress overrides the positive direct effect of warming on Rs. Our results also imply the necessity of considering the different Rs responses in the growing and non-growing seasons to climate change to accurately evaluate the carbon cycle in the arid and semi-arid regions.

Low-Grade Myofibroblastic Sarcoma in the Mandibular Canal: A Case Report.

Low-grade myofibroblastic sarcoma (LGMS) represents an atypical myofibroblastic tumor characterized by a diffusely infiltrating pattern of spindle-shaped tumor cells. It was classified as a distinct soft tissue tumor by the World Health Organization in 2002. LGMS occurs mostly in adult patients and has a predilection for the head and neck region. So far, only a few cases of LGMS located in the mandible have been reported. Aggressive surgical resection with clear margins is the primary treatment for LGMS. Because of its rarity, reports of radiation therapy are limited, and the therapeutic effect is still controversial. We present the case of an 8-year-old girl with LGMS of the mandibular canal to highlight the clinical features and rarity and to improve the understanding of the therapeutic effect of radiotherapy on LGMS.

[A study of repairing mandibular defect using tissue engineering bone with bone marrow stem cells cell sheets in dog].

OBJECTIVE: To reconstruct mandibular defect using tissue engineering bone with bone marrow stem cells (BMSCs) cell sheets and investigate the effect of cell sheets on osteogenesis. METHODS: BMSCs were isolated with the method of density gradient centrifugation from canine and cultured. BMSCs were induced to differentiate to osteoblasts. BMSCs induced were fabricated to BMSCs cell sheets. The poly (lactic-co-glycolic acid) (PLGA) wrapped with cell sheets were implanted into the mandibular defect in the left side (experimental side). PLGA wrapped without cell sheets were implanted into the right side (control side) of mandibles. 16 dogs were evenly divided into 4 groups, and one group of them was executed in 4, 8, 12, 16 weeks for gross investigation and histological observation. RESULTS: The osteogenesis of experimental side was better than that of control side. 16 weeks after implantation, most areas of the mandibular defect were replaced by fresh bone tissue. Compact bone similar to normal bone tissue formed in the lingual defect of mandible and had bony union with the bone stump. The optical density of the fresh bone in the experimental side was higher than that of the control side, there was a significant difference between the two methods (P<0.05). Plenty of lamellar bones formed in experimental side and Haversian system, as well as red marrow, were observed. CONCLUSION: Tissue engineering bone with the structure of lamellar bones can be formed by the technology of BMSCs cell sheets.