Comparison of the dimensional and morphological accuracy of three-dimensional digital dental casts digitized using different methods.

The purpose of this study was to compare the accuracy of digital dental casts from plaster cast scanning (PCS), impression scanning (IPS), intraoral scanning (IOS), and cone-beam computed tomography (CBCT) scanning (CCS) methods. The maxillary and mandibular dental casts of 15 patients who needed CBCT scans for oral examination or treatment were digitized via four methods. 12 linear distance measurements of all digital dental casts were selected and acquired with software and compared to those of the reference plaster cast to evaluate the dimensional accuracy. Three-dimensional deviation analysis of the IPS, IOS and CCS groups with respect to the reference PCS group was performed to evaluate the morphological accuracy. The discrepancy in linear distances between the digital dental casts and reference plaster casts was statistically significant (p < 0.01). The dimensional accuracies of the PCS (0.06 ± 0.12 mm) and IPS (0.03 ± 0.05 mm) casts were better than those of the IOS (0.37 ± 0.30 mm) and CCS (0.54 ± 0.40 mm) casts. The one-sample t test showed that there were statistically significant differences between the discrepancies in 8 of the linear distances for the PCS group and 9 of the linear distances for the IPS group between the digital dental casts and reference plaster casts, with an ideal error of 0.00 (p < 0.05). The sequence of morphological accuracy from good to poor was maxillary and mandibular IPS, mandibular IOS; maxillary IOS; and maxillary and mandibular CCS. The accuracy of the digital dental casts from the PCS and IPS methods was greater than that of IOS and CCS methods. Although accuracy of the digital dental cast from IOS was low, it satisfied the clinical requirements for fixed restorations in small units. The accuracy of the digital dental cast from CCS was poorest and could only be used for procedures with lower accuracy requirements.

Comparison of the accuracy (trueness and precision) of virtual dentofacial patients digitized by three different methods based on 3D facial and dental images.

STATEMENT OF PROBLEM: The accuracy of virtual dentofacial patients has been explored, but the accuracy of virtual patients established by using a straightforward and reliable method and the accuracy of different virtual patients are unclear. PURPOSE: The purpose of this clinical study was to compare the accuracy of virtual dentofacial patients digitized by using registered-block impression, exposed anterior teeth, and cone beam computed tomography (CBCT) reconstruction methods based on 3-dimensional (3D) facial and dental images. MATERIAL AND METHODS: From the 15 selected participants who needed CBCT scanning, 3 kinds of virtual dentofacial patients were established by using 3 registration methods based on digital dental casts: 3D facial images, CBCT data, and registered-block impression. Compared with actual measurement, 25 linear distances of all virtual dentofacial patients were selected and measured by using a software program, and 3 separate measurements were calculated by the same person. The 1-way analysis of variance (ANOVA) was used to compare the deviations among 3 kinds of virtual dentofacial patients (trueness) and the deviations within groups (precision). The 1-sample t test was used to compare the difference between the deviation and the ideal error of 0.00 (α=.05). RESULTS: Compared with the actual measurement, the trueness of the average deviations for registered-block impression (1.02 ±1.24 mm) was better than that of exposed anterior teeth (2.35 ±1.71 mm) and CBCT reconstruction (2.86 ±1.61 mm). The precision of the average deviations for registered-block impression (1.29 ±1.43 mm) was better than that of exposed anterior teeth (2.00 ±1.72 mm) and CBCT reconstruction (2.12 ±1.94 mm). Significant differences in trueness and precision were found among the 3 groups of virtual dentofacial patients (P<.01). Significant differences among the deviations of all linear distances and the ideal error of 0.00 were observed for all groups of virtual dentofacial patients (P<.05). CONCLUSIONS: The accuracy of registered-block impression was better than that of the exposed anterior teeth and CBCT reconstruction. The accuracy of exposed anterior teeth was lower than that of the other methods but could satisfy the requirements of clinical diagnostics and scientific methods. The accuracy of CBCT reconstruction was poor and could only be used for special situations that permitted low accuracy.

Facile Fluorescence Dopamine Detection Strategy Based on Acid Phosphatase (ACP) Enzymatic Oxidation Dopamine to Polydopamine.

Facile and effective detection of dopamine (DA) plays a significant role in current clinical applications. Substantially, special optical nanomaterials are important for fabricating easy-to-control, cheap, selective, and portable fluorescence DA sensors with superior performance. Herein, carbon dots (CDs) prepared from melting method were applied as signal to establish a simple but effective fluorescence strategy for DA determination based on the enzymatic activity of acid phosphatase (ACP), which induces DA to form polydopamine (pDA). The formed pDA caused by the enzymatic oxidization of ACP toward DA can interact with CDs through the inner filter effect. Such behavior effectively quenched the CDs' fluorescence. The degree of fluorescence quenching of CDs was positively correlated with the DA content. Under the optimized reaction conditions, the proposed fluorescence method exhibited a comparable analytical performance with other DA sensors with good selectivity. Furthermore, this method has been successfully applied to detect DA in DA hydrochloride injection and human serum samples. It shows that this method features potential practical application value and is expected to be used in clinical research.

Precision targeting of CuET overload to disrupt mitochondrial unfolded protein response by integrated liposome.

Mitochondria in breast cancer play a critical role in survival and adaptation to dynamic environments. Thus, targeting mitochondria emerges as a promising therapeutic strategy for breast cancer. However, the adaptive unfolded protein response in mitochondria (UPRmt) due to mitochondrial unspecific distribution might contribute to diminished therapeutic outcomes. Herein, mitochondrial targeting liposome agents (CTPP-Lipid) are constructed and adopted for delivering the copper ion (CuET-DSF), which is especially sensitive for mitochondria-abundant breast tumors. In brief, the CTPP-Lipid@CuET achieves the goal of Cu2+ overloading by mitochondria targeting delivery. This rapidly increases ROS production, disrupts mitochondrial structure, and avoids the adaptive UPRmt formation, finally leading to apoptosis of breast cancer cells. In general, the Cu2+ overloading at mitochondria by CTPP-Lipid@CuET is a potential strategy for antitumor therapy, providing new insights into breast tumor therapy.

[Effectiveness of TiRobot-assisted and free-hand percutaneous kyphoplasty via pedicle of vertebra in treatment of osteoporotic vertebral compression fracture of thoracic vertebra].

Objective: To compare the effectiveness of TiRobot-assisted and C-arm X-ray fluoroscopy assisted percutaneous kyphoplasty (PKP) via pedicle of vertebra in the treatment of osteoporotic vertebral compression fracture (OVCF) of thoracic vertebrae. Methods: The clinical data of 85 patients with OVCF of thoracic vertebrae who were admitted between January 2020 and March 2023 and met the selection criteria was retrospectively analyzed including 40 patients (50 vertebrae) undergoing PKP assisted by TiRobot (group A) and 45 patients (50 vertebrae) undergoing PKP assisted by C-arm X-ray fluoroscopy (group B). There was no significant difference in the comparison of baseline data such as gender, age, body mass index, bone mineral density T-value, fracture segment, trauma history, and preoperative numerical rating scale (NRS) score, Oswestry disability index (ODI), and Cobb angle of injured vertebra between the two groups ( P>0.05). The effectiveness evaluation indexes of the two groups, including the operation time, the volume of injected cement, the times of fluoroscopies, the length of hospital stay, and the occurrence of postoperative complications were collected and compared. Anteroposterior and lateral X-ray films and CT of the injured vertebra were reviewed at 1 day after operation to observe whether there was cement leakage and to evaluate the distribution of cement in the injured vertebra. Before and after operation, pain was assessed using the NRS score, dysfunction was assessed using the ODI, and vertebral height recovery was assessed by measuring the Cobb angle of the injured vertebrae by X-ray films. Results: Both groups of patients successfully completed the operation, the operation time, the volume of injected cement, the times of fluoroscopies, and the length of hospital stay in group A were significantly less than those in group B ( P<0.05). The patients in two groups were followed up 4-12 months (mean, 9.6 months). Bone cement leakage occurred in 5 vertebrae in group A and 15 vertebrae in group B after operation, all of which leaked to the intervertebral space and around the vertebral body, and the patients had no obvious clinical symptoms. The difference of bone cement leakage between the two groups was significant ( P<0.05). No severe complication such as intraspinal leakage, infection, or vascular embolism was found in the two groups. At 1 day after operation, the distribution index of bone cement in group A was mostly grade Ⅴ, which was well dispersed; while in group B, it was mostly grade Ⅱ and grade Ⅴ; the difference of bone cement distribution index between the two groups was significant ( P<0.05). The NRS score, ODI, and Cobb angle of injured vertebra in both groups were significantly improved at 1 day after operation when compared with preoperative ones ( P<0.05). There was no significant difference in the difference of the above indexes between the two groups before and after operation ( P>0.05). Conclusion: TiRobot-assisted unilateral PKP in the treatment of OVCF of thoracic vertebrae is safe and effective, which can reduce the X-ray transmission times during operation, shorten the operation time, reduce the volume of bone cement injection, and thus decrease incidence of bone cement leakage.

A shear-thinning, ROS-scavenging hydrogel combined with dental pulp stem cells promotes spinal cord repair by inhibiting ferroptosis.

Spinal cord injury (SCI) is a serious clinical disease. Due to the deformability and fragility of the spinal cord, overly rigid hydrogels cannot be used to treat SCI. Hence, we used TPA and Laponite to develop a hydrogel with shear-thinning ability. This hydrogel exhibits good deformation, allowing it to match the physical properties of the spinal cord; additionally, this hydrogel scavenges ROS well, allowing it to inhibit the lipid peroxidation caused by ferroptosis. According to the in vivo studies, the TPA@Laponite hydrogel could synergistically inhibit ferroptosis by improving vascular function and regulating iron metabolism. In addition, dental pulp stem cells (DPSCs) were introduced into the TPA@Laponite hydrogel to regulate the ratios of excitatory and inhibitory synapses. It was shown that this combination biomaterial effectively reduced muscle spasms and promoted recovery from SCI.

Sprayable hydrogel for biomedical applications.

Polymeric hydrogels have extraordinary potential to be utilized for biomedical applications. Recently, sprayable hydrogels have received increasing attention for their biocompatibility, degradability, tunable mechanical properties and rapid spray-filming abilities. In this review, hydrogel-based biomaterials, especially those based on natural polymers, such as polysaccharides and proteins, have been explained. The focus of this review lies on illuminating recent advances in sprayable hydrogel systems and highlighting the properties and applications of sprayable hydrogels, such as wound management, postoperative adhesion and cancer therapeutics. In addition, future research directions and challenges are also discussed.

Quality of life in patients with cancer-related Brown IIb maxillary defect: A comparison between conventional obturation rehabilitation and submental flap reconstruction.

OBJECTIVES: The purpose of this retrospective study was to compare the differences in quality of life (QOL) outcomes between the conventional obturator prostheses (COP) and the pedicled submental artery island flap (SAIF) in the reconstruction of Brown IIb maxillary defects. MATERIALS AND METHODS: The QOL of 116 eligible patients who had a lapse ≥ 12 months after the cancer-related maxilla ablation was evaluated by the University of Washington quality of life scale (UW-QOL), Performance Status Scale for Head and Neck (PSS-HN), and Obturator Functioning Scale (OFS). RESULTS: Patients in the SAIF group reported statistically and clinically significant higher overall QOL scores but lower chewing scores in the UW-QOL scale when compared with those in the COP group (P < 0.05). Clinically significantly higher scores were also observed in the recreation and anxiety domains in the UW-QOL scale for the SAIF group, but there was no statistical significances. The COP group reported more complaints about the nasal leakage when swallowing and the shape of the upper lip, and had a stronger willingness to avoid family or social events in the OFS (P < 0.05). CONCLUSIONS: For patients with Brown IIb defects, SAIF reconstruction can achieve reduced nasal leakage when swallowing, improved upper-lip contour, increased social activity, and superior overall QOL than COP. The inferior chewing function in the SAIF group indicated the need for dental rehabilitation with a conventional denture or osseointegrated implants.

Integration of fluorescent polydopamine nanoparticles on protamine for simple and sensitive trypsin assay.

As an important protease, trypsin (TRY) has been identified as a key indicator of various diseases. A simple and sensitive strategy for TRY detection by using an environment-friendly biosafe probe is significant. Herein, we introduced negatively charged fluorescent polydopamine nanoparticles (PDNPs) with 4.8 nm diameter obtained through a controllable method as an effective probe for TRY. PDNPs exhibited excellent fluorescence property but integrated with protamine (Pro) to form an aggregation-caused quenching system via a static quenching mechanism. The quenching mechanism of Pro to PDNPs revealed the significant effect of the surface charge, functional groups, and appropriate size of PDNPs on quenching process. Given the specific hydrolysis of Pro by TRY, PDNPs were released from the quenching integration of PDNPs and Pro (PDNPs-Pro) and recovered their fluorescence. Thus, a fluorescence sensor for TRY with a linear range of 0.01 and 0.1 µg/mL and a detection limit of 6.7 ng/mL was developed without the disturbing from other proteases. Compared with other TRY assays, the biosensor based on PDNPs-Pro has the advantages of simple operation, environmental friendliness, and high sensitivity. This specific controlled-synthesis PDNPs would open up a new window for the extended application of fluorescent nanomaterials in biomedicine based on fluorescence changes induced by biological interaction.

Hypoxia response element-directed expression of bFGF in dental pulp stem cells improve the hypoxic environment by targeting pericytes in SCI rats.

Cell-based transplantation strategies possess great potential for spinal cord injury (SCI) repair. Basic fibroblast growth factor (bFGF) has been reported to have multiple neuro-promoting effects on developing and adult nervous system of mammals and considered a promising therapy for nerve injury following SCI. Human dental pulp stem cells (DPSCs) are abundant stem cells with low immune rejection, which can be considered for cell replacement therapy. The purpose of this study was to investigate the roles of DPSCs which express bFGF under the regulation of five hypoxia-responsive elements (5HRE) using an adeno-associated virus (AAV-5HRE-bFGF-DPSCs) in SCI repairing model. In this study, DPSCs were revealed to differentiate into CD13+ pericytes and up-regulate N-cadherin expression to promote the re-attachment of CD13+ pericytes to vascular endothelial cells. The re-attachment of CD13+ pericytes to vascular endothelial cells subsequently increased the flow rate of blood in microvessels via the contraction of protuberance. As a result, increased numbers of red blood cells carried more oxygen to the damaged area and the local hypoxia microenvironment in SCI was improved. Thus, this study represents a step forward towards the potential use of AAV-5HRE-bFGF-DPSCs in SCI treatment in clinic.