Outcome of chairside CAD/CAM ceramic restorations on endodontically treated posterior teeth: a prospective study.

OBJECTIVE: The aim of this study was to evaluate the outcome and risk factors for chairside CAD/CAM full cusp coverage restorations on endodontically treated posterior teeth after 3 years of follow-up. METHODS: A total of 245 endodontically treated posterior teeth of 224 patients were included and restored with CAD/CAM full cusp coverage all-ceramic restorations according to a standardized protocol. Patients were recalled after treatments 1 to 3 years and underwent clinical and radiological examinations. At recall, modified FDI criteria were used to determine treatment outcomes by 2 evaluators. Success was determined when FDI scores were 1-2, and failure was indicated when FDI scores were 5. Logistic regression analysis was performed to evaluate potential risk factors. RESULTS: A total of 183 patients presented at recall, and the clinical outcomes of 201 teeth were analyzed with a recall rate of 82.0% for teeth and 81.7% for patients after 1-3 years of follow-up.185 of 201 teeth were found to have FDI scores of 1-2, and the success rate was 92%. No teeth were extracted during the follow-up period. Fourteen failed cases with an FDI score of 5 presented restoration dislocation, fracture of restoration or/and tooth. Logistic regression analysis revealed that oral parafunction (OR 2.281, 95% CI 2.2 ~ 47.5, P value 0.01) was a risk factor for success rate. CONCLUSION: Chairside CAD/CAM all-ceramic full cusp coverage restoration was (could be) a promising alternative for restoring endodontically treated posterior teeth.

Cost-effectiveness analysis: nonsurgical root canal treatment versus single-tooth implant.

BACKGROUND: Economic evaluation of nonsurgical root canal treatment (NSRCT) and single-tooth implant (STI) provides useful information for medical decision. This retrospective study aimed to evaluate the cost-effectiveness of NSRCT versus single-tooth implant (STI) after 5-year treatment in a university affiliated hospital in Beijing, China. METHODS: 211 patients who underwent NSRCT and 142 patients who had STI were included and recalled after 5-year treatment. The propensity scores were used to match the cases of two treatment modalities. At recall, outcomes were determined based on clinical and radiographical examinations. For endodontically treated cases, absence or reduction of radiolucency were defined as success. Marginal bone loss (MBL) ≤ 4 mm were determined as success for implant cases. Direct and indirect costs were calculated in China Yuan (CNY). Patients' willingness to pay (WTP) for each treatment modality was evaluated by questionnaires. A cost-effectiveness analysis was performed from the societal perspective. RESULTS: 170 patients with 120 NSRCT teeth and 96 STI were available at recall. Based on propensity score matching, 76 endodontically treated teeth were matched to 76 implants. Absence of the radiolucency was observed in 58 of 76 endodontically treated teeth (76%) and reduction of the radiolucency in 9 of 76 teeth (12%) and altogether the success rate was 88%. 100% implants were detected with marginal bone loss (MBL) ≤ 4 mm. The cost advantage of NSRCT (4,751 CNY) over STI (20,298 CNY) was more pronounced. Incremental cost effectiveness ratio (ICER) was 129,563 CNY (STI-NSRCT) per success rate gained. It exceeded the patients' willingness to pay value 7,533 CNY. CONCLUSIONS: Clinical outcomes of NSRCT and STI could be predictable after 5-year treatment. NSRCT may be more cost-effective than STI for managing endodontically diseased teeth.

Cyclized Polyacrylonitrile as a Promising Support for Single Atom Metal Catalyst with Synergistic Active Site.

Metal single atom catalysts (SAC) have been successfully used in heterogeneous catalysis but developing a scalable and economic support for SAC is still a great challenge. Here, cyclized polyacrylonitrile (CPAN) is proposed as a promising support for single atom metal catalysts. CPAN can be easily prepared from cheap industrial product polyacrylonitrile (PAN), which has excellent processability. A series of SAC on CPAN (M/CPAN, M = Ag, Cu, Ru) are designed and the catalytic activities of the as synthesized M/CPAN are investigated by the model reduction reaction of p-nitrophenol (4-NP). M/CPAN presents excellent catalytic performance with high stability and theoretical calculations elucidate that Ag/CPAN synergistically catalyze 4-NP reduction following the Langmuir-Hinshelwood (L-H) mechanism with 4-NP preferentially adsorbing at the Ag sites and H adsorbing at the bridge C sites. These results, for the first time, reveal that the single atom on CPAN can catalyze 4-NP reduction efficiently. This methodology provides a convenient route for the preparation of a variety of SAC, and this strategy is readily scalable and holds great potential in catalytic applications.

Prophylactic Penehyclidine Inhalation for Prevention of Postoperative Pulmonary Complications in High-risk Patients: A Double-blind Randomized Trial.

BACKGROUND: Postoperative pulmonary complications are common. Aging and respiratory disease provoke airway hyperresponsiveness, high-risk surgery induces diaphragmatic dysfunction, and general anesthesia contributes to atelectasis and peripheral airway injury. This study therefore tested the hypothesis that inhalation of penehyclidine, a long-acting muscarinic antagonist, reduces the incidence of pulmonary complications in high-risk patients over the initial 30 postoperative days. METHODS: This single-center double-blind trial enrolled 864 patients age over 50 yr who were scheduled for major upper-abdominal or noncardiac thoracic surgery lasting 2 h or more and who had an Assess Respiratory Risk in Surgical Patients in Catalonia score of 45 or higher. The patients were randomly assigned to placebo or prophylactic penehyclidine inhalation from the night before surgery through postoperative day 2 at 12-h intervals. The primary outcome was the incidence of a composite of pulmonary complications within 30 postoperative days, including respiratory infection, respiratory failure, pleural effusion, atelectasis, pneumothorax, bronchospasm, and aspiration pneumonitis. RESULTS: A total of 826 patients (mean age, 64 yr; 63% male) were included in the intention-to-treat analysis. A composite of pulmonary complications was less common in patients assigned to penehyclidine (18.9% [79 of 417]) than those receiving the placebo (26.4% [108 of 409]; relative risk, 0.72; 95% CI, 0.56 to 0.93; P = 0.010; number needed to treat, 13). Bronchospasm was less common in penehyclidine than placebo patients: 1.4% (6 of 417) versus 4.4% (18 of 409; relative risk, 0.327; 95% CI, 0.131 to 0.82; P = 0.011). None of the other individual pulmonary complications differed significantly. Peak airway pressures greater than 40 cm H2O were also less common in patients given penehyclidine: 1.9% (8 of 432) versus 4.9% (21 of 432; relative risk, 0.381; 95% CI, 0.171 to 0.85; P = 0.014). The incidence of other adverse events, including dry mouth and delirium, that were potentially related to penehyclidine inhalation did not differ between the groups. CONCLUSIONS: In high-risk patients having major upper-abdominal or noncardiac thoracic surgery, prophylactic penehyclidine inhalation reduced the incidence of pulmonary complications without provoking complications.

Manipulation of amorphous precursors to enhance zeolite nucleation.

Crystallization in media comprised of amorphous precursors is becoming a more common phenomenon for numerous synthetic, biological, and natural materials that grow by a combination of classical and nonclassical pathways. Amorphous phases can exhibit a wide range of physicochemical properties that may evolve during the course of nucleation and crystal growth. This creates challenges for establishing causal relationships between amorphous precursor properties and their effect(s) on the selection of mechanistic pathways of crystallization and ultimately the properties of the crystalline product. In this study, we examine ways to manipulate the composition and colloidal stability of amorphous (alumino)silicate precursors that are prevalent in nanoporous zeolite syntheses. Changes in the amorphous precursor properties are evaluated on the basis of their ability to enhance rates of crystal formation. Here, we use fumed silica as the primary silicon source and examine the effects of infusing the source or growth medium with additional alkali metal, which serves as an inorganic structure-directing agent to facilitate the formation of porous crystal structures. We also assess the impact of adding a polymer additive, which reduces the colloidal stability of precursors, wherein we posit that the confined pockets of solution within the interstitial spaces of the precursor aggregates play an important role in regulating the rate of zeolite crystallization. Three commercially relevant zeolites (mordenite, SSZ-13, and ZSM-5) were selected for this study based on their diverse frameworks and methods of preparation. Our findings reveal that alkali infusion significantly reduces the crystallization times for mordenite and SSZ-13, but has little impact on ZSM-5 synthesis. Conversely, we find that polymer addition markedly enhanced the rates of crystallization among all three zeolites, suggesting that this method may be a general approach to reduce zeolite synthesis times. Given the relatively high costs associated with commercial zeolite production, identifying new methods to improve the efficiency of hydrothermal syntheses can have significant practical implications beyond the fundamental benefits of developing new routes to tailor nonclassical crystallization.

Nutritional status in patients of mandibular osteoradionecrosis: A single-institution experience.

BACKGROUND: Mandibular osteoradionecrosis (ORN) is a devastating complication secondary to the radiotherapy of head and neck cancer. The nutritional status of ORN patients is compromised, but remains rarely studied. We aimed to evaluate the overall nutritional status of patients with ORN and explore the risk factors behind poor nutrition. METHODS: This is a single-institution cross-sectional study. Patients diagnosed with ORN were consecutively recruited in a tertiary teaching hospital from July 2017 to August 2019. Multiple laboratory markers and physical indicators were examined to profile their nutritional status. The potential risk factors of poor nutrition were explored by logistic regression. RESULTS: A total of 107 patients with ORN were recruited. Among them, almost all patients (95.3%) had at least one laboratory marker lower than the normal physiological range. A total of 40 (37.5%) patients were categorized as undernutrition, who had lower serum albumin (mean difference: 1.8 ± 0.8 g/L; p = .02), prealbumin (mean difference: 26.8 ± 10.8 mg/L; p = .02), and BMI (3.8 ± 0.4 kg/m2 ; p < .0001) compared to patients of normal nutrition. Notably, the multivariate logistic regression indicated that patients with semi-liquid diet had 14.41 (95% CI: 3.03-68.54, p = .001) times; patients with liquid diet had 5.70 (95% CI: 1.55-20.98, p = .009) times more likely to be in undernutrition, as compared to patients with regular diets. CONCLUSIONS: This is the first study characterizing the poor nutritional status in ORN patients. Patients having semi-liquid or liquid diets tended to have poorer nutritional status. The nutritional status of ORN patients should be underlined for professional nutritional supports so as to enhance their quality of life. More studies are warranted.

Aspirin/PLGA coated 3D-printed Ti-6Al-4V alloy modulate macrophage polarization to enhance osteoblast differentiation and osseointegration.

Although titanium (Ti) and Ti-based alloy have been widely used as dental and orthopedic implant materials, its bioinertness hindered the rapid osseointegration. Therefore, it is recommended to acquire ideal topographic and chemical characteristics through surface modification methods. 3D printing is a delicate manufacture technique which possesses superior controllability and reproducibility. While aspirin serve as a well-established non-steroidal anti-inflammatory agent. Recently, the importance of immune system in regulating bone dynamics has attracted increasing attention. We herein superimposed the aspirin/poly (lactic-co-glycolic acid) (ASP/PLGA) coating on the 3D-printed Ti-6Al-4V surface with uniform micro-structure to establish the Ti64-M-ASP/PLGA substrate. Scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS) and contact angle test confirmed the successful fabrication of the Ti64-M-ASP/PLGA substrate, with increased wettability and sustained release pattern of ASP. Compared with the Ti64 base material, the Ti64-M-ASP/PLGA substrate showed enhanced M2 and depressed M1 genes and proteins expressions in macrophages. The novel Ti64-M-ASP/PLGA substrate also displayed enhanced osteoblast proliferation, adhesion, extracellular mineralization ability and osteogenic gene expressions when cultured with macrophage conditioned medium in vitro. Furthermore, rat femora implantation model was used for in vivo evaluation. After 4 weeks of implantation, push out test, micro-computed tomography (micro-CT) and histological analyses all confirmed the superior osseointegration capabilities of the Ti64-M-ASP/PLGA implant than the other groups. Our study revealed the synergistic role played by 3D-printed micro topography and immunoregulatory drug aspirin in promoting osteogenesis in vitro and accelerating osseointegration in vivo, thus providing a promising method for better modifying the implant surface. Graphical abstract.

The functional motions and related key residues behind the uncoating of coxsackievirus A16.

The coxsackievirus A16 (CVA16) is a highly contagious virus that causes the hand, foot, and mouth disease, which seriously threatens the health of children. At present, there are still no available antiviral drugs or effective treatments against the infection of CVA16, and thus it is of great significance to develop anti-CVA16 vaccines. However, the intrinsic uncoating property of the capsid may destroy the neutralizing epitopes and influence its immunogenicity, which hinders the vaccine developments. In the present work, the functional-quantity-based elastic network model analysis method developed by our group was extended to combine with group theory to investigate the uncoating motions of the CVA16 capsid, and then the functionally key residues controlling the uncoating motions were identified by our functional-quantity-based perturbation method. Several motion modes encoded in the topological structure of the capsid were revealed to be responsible for the uncoating of CVA16 particle. These modes predominantly contribute to the fluctuation of the gyration radius of the capsid. Then, by using the perturbation method, four clusters of key sites involved in the uncoating motions were identified, whose perturbations induce significant changes in the fluctuation of the gyration radius. These key residues are mainly located at the 2-fold channels, the quasi 3-fold channels, the bottom of the canyons, and the inter-subunit interfaces around the 3-fold axes. Our studies are helpful for better understanding the uncoating mechanism of the CVA16 capsid and provide potential target sites to prevent the uncoating motions, which is valuable for the vaccine design against CVA16.

Liposomal paclitaxel versus docetaxel in induction chemotherapy using Taxanes, cisplatin and 5-fluorouracil for locally advanced nasopharyngeal carcinoma.

BACKGROUND: We wished to evaluate the efficacy and safety of liposomal paclitaxel and docetaxel for induction chemotherapy (IC) for nasopharyngeal carcinoma (NPC). METHODS: A total of 1498 patients with newly-diagnosed NPC between 2009 and 2017 treated with IC plus concurrent chemotherapy were included in our observational study. Overall survival (OS), progression-free survival (PFS), locoregional relapse-free survival (LRFS), distant metastasis-free survival (DMFS) and grade-3-4 toxicities were compared between groups using propensity score matching (PSM). RESULTS: In total, 767 patients were eligible for this study, with 104 (13.6%) and 663 (86.4%) receiving a liposomal paclitaxel-based and docetaxel-based taxanes, cisplatin and 5-fluorouracil (TPF) regimen, respectively. PSM identified 103 patients in the liposomal-paclitaxel group and 287 patients in the docetaxel group. There was no significant difference at 3 years for OS (92.2% vs. 93.9%, P = 0.942), PFS (82.6% vs. 81.7%, P = 0.394), LRFS (94.7% vs. 93.3%, P = 0.981) or DMFS (84.6% vs. 87.4%, P = 0.371) between the two groups after PSM. Significant interactions were not observed between the effect of chemotherapy regimen and sex, age, T stage, N stage, overall stage, or Epstein-Barr virus DNA level in the subgroup multivariate analysis. The prevalence of grade-3-4 leukopenia and neutropenia in the liposomal-paclitaxel group was significantly lower than that of the docetaxel group (P < 0.05 for all). CONCLUSIONS: Compared with docetaxel, liposomal paclitaxel has identical anti-tumor efficacy, but causes fewer and milder adverse reactions in IC for NPC.

[Molecular imprinting technology and its application in terpenoids].

Molecular imprinting technology is widely used in the separation and analysis of compounds such as flavonoids, alkaloids and polyphenols, due to its high selectivity and specific recognition and so on. However, no much of attention has been paid to the terpenoids. This paper is aimed to not only review the effects of common synthetic elements such as functional monomers, cross-linking agents and porogens on the polymer properties, but also highlight the application of terpene molecular imprinting in solid phase extraction, sensor, membrane separation and chromatographic separation by means of statistical analysis of literature. Furthermore, the shortcomings and improvement directions are discussed.We believed that this paper could provide references for better applications of molecular imprinting techniques to the analysis of terpenoid compounds.

Does the Surgery-First Approach Produce Better Outcomes in Orthognathic Surgery? A Systematic Review and Meta-Analysis.

PURPOSE: The surgery-first approach (SFA) in orthognathic surgery, performed without presurgical orthodontic treatment, has gained attention, but the results remain controversial. The purpose of this study was to assess the current evidence on stability, efficacy, and surgical results of SFA versus conventional 3-stage method (CTM) orthognathic surgery. MATERIALS AND METHODS: A comprehensive search in PubMed and Web of Science was conducted. A systematic review and cumulative meta-analysis of all comparative studies were performed to assess the 2 strategies (SFA and CTM) using a random- or a fixed-effects model. Outcomes included treatment duration, postoperative stability, surgical movement, and postoperative occlusion. RESULTS: Ten nonrandomized controlled studies including 513 patients were identified. Compared with CTM, patients in the SFA group benefited from shorter total treatment duration (weighted mean difference [WMD], -5.25; 95% confidence interval [CI], -8.21 to -2.29; P = .0005), similar postoperative stability of the mandible (WMD, 0.35 mm; 95% CI, -0.24 to 0.94; P = .55) and maxilla (WMD, 0.13 mm; 95% CI, -0.35 to 0.60; P = .60), similar surgical movements, and other surgical results. CONCLUSIONS: SFA offers an efficient alternative to CTM with shorter total treatment duration, similar postoperative stability, and other surgical results but longer postoperative orthodontic time.

A transgenic plant cell-suspension system for expression of epitopes on chimeric Bamboo mosaic virus particles.

We describe a novel strategy to produce vaccine antigens using a plant cell-suspension culture system in lieu of the conventional bacterial or animal cell-culture systems. We generated transgenic cell-suspension cultures from Nicotiana benthamiana leaves carrying wild-type or chimeric Bamboo mosaic virus (BaMV) expression constructs encoding the viral protein 1 (VP1) epitope of foot-and-mouth disease virus (FMDV). Antigens accumulated to high levels in BdT38 and BdT19 transgenic cell lines co-expressing silencing suppressor protein P38 or P19. BaMV chimeric virus particles (CVPs) were subsequently purified from the respective cell lines (1.5 and 2.1 mg CVPs/20 g fresh weight of suspended biomass, respectively), and the resulting CVPs displayed VP1 epitope on the surfaces. Guinea pigs vaccinated with purified CVPs produced humoral antibodies. This study represents an important advance in the large-scale production of immunopeptide vaccines in a cost-effective manner using a plant cell-suspension culture system.

[Comparison of effectiveness and safety between Twisted File technique and ProTaper Universal rotary full sequence based on micro-computed tomography].

OBJECTIVE: To evaluate the efficacy and security of two type of rotary nickel titanium system (Twisted File and ProTaper Universal) for root canal preparation based on micro-computed tomography(micro-CT). METHODS: Twenty extracted molars (including 62 canals) were divided into two experimental groups and were respectively instrumented using Twisted File rotary nickel titanium system (TF) and ProTaper Universal rotary nickel titanium system (PU) to #25/0.08 following recommended protocol. Time for root canal instrumentation (accumulation of time for every single file) was recorded. The 0-3 mm root surface from apex was observed under an optical stereomicroscope at 25 × magnification. The presence of crack line was noted. The root canals were scanned with micro-CT before and after root canal preparation. Three-dimensional shape images of canals were reconstructed, calculated and evaluated. The amount of canal central transportation of the two groups was calculated and compared. RESULTS: The shorter preparation time [(0.53 ± 0.14) min] was observed in TF group, while the preparation time of PU group was (2.06 ± 0.39) min (P<0.05). In mid-root level, TF group shaping resulted in less canal center transportation than PU group [(0.070 ± 0.056) mm vs. (0.097 ± 0.084) mm, P<0.05]. No instrument separation was observed in both the groups. Cracks were not found in both the groups either based in micro-CT images or observation under an optical stereomicroscope at 25 × magnification. CONCLUSION: Compared with ProTaper Universal, Twisted File took less time in root canal preparation and exhibited better shaping ability, and less canal transportation.

[Comparison of the incidences of apical root cracks after canal preparation with two nickel-titanium rotary systems: an in vitro study].

OBJECTIVE: To compare the incidences of root cracks after canal instrumentation with HyFlex CM system and the ProTaper Universal system. METHODS: Sixty mandibular incisors were mounted in resin blocks with simulated periodontal ligaments, and the apex was exposed. The control group of 20 teeth was not prepared, and the other 40 teeth were divided into 2 experimental groups (n=20). The 40 root canals of the experimental groups were instrumented using HyFlex CM and ProTaper Universal to the major apical foramen (AF). The horizontal sections 1 mm, 2 mm, and 3 mm from the apex were observed under an optical stereomicroscope at 25×magnification. The presence of cracks was noted. RESULTS: No cracks were found in the control teeth. Cracks were found in 1 of 20 (5%) teeth in HyFlex CM group, and 17 of 20 (85%) teeth in ProTaper Universal group. The difference between the two experimental groups was statistically significant (P<0.01). CONCLUSION: The HyFlex CM files caused fewer root cracks than the ProTaper Universal files during the root canal instrumentation.

[Real temperature of the continuous-wave pluggers].

OBJECTIVE: To measure the real temperatures on the pluggers of three continuous-wave devices, and to provide theoretical reference to evaluate thermal damage and heat's influence on the filling materials. METHODS: The dual channel K type thermocouple was contacted to various sizes' pluggers in three different continuous-wave devices (BeeFill, Elements, B&L), and the highest temperatures at different points (tip, and 2 mm, 5 mm, 10 mm from the tip) of the pluggers (preset temperature was 200 °C) were recorded. The measurements were performed 5 times. T-test was used to compare the real temperatures at the tips with that set on the display and one-way ANOVA was used to compare the temperatures of the pluggers in different devices, sizes and points. RESULTS: The highest temperature was at the tip of BeeFill 40/0.03 plugger (198.7±7.7) °C, but there was on statistical differences between that and the preset temperature 200 °C. The temperatures of the remaining pluggers were obviously lower than 200 °C (P<0.05). The lowest temperature of the pluggers was detected at 10 mm from the tip of BeeFill 60/0.06 plugger (69.9±4.0) °C. The highest temperature of each plugger was detected at the tip or 2 mm from the tip (112.1 to 198.7 °C,and the median was 140.8 °C). CONCLUSION: The real temperature of most continuous-wave pluggers included in this study is below the set temperature 200 °C.

Boronate affinity monolith with a gold nanoparticle-modified hydrophilic polymer as a matrix for the highly specific capture of glycoproteins.

As low abundance is the great obstacle for glycoprotein analysis, the development of materials with high efficiency and selectivity for glycoprotein enrichment is a prerequisite in glycoproteome research. Herein, we report a new kind of hydrophilic boronate affinity monolith by attaching 4-mercaptophenylboronic acid (MPBA) with 2-mercaptoethylamine (MPA) on the gold nanoparticle-modified poly(glycidyl methacrylate-co-poly(ethylene glycol) diacrylate)) monolith for glycoprotein enrichment. With poly(ethylene glycol) diacrylate as the cross-linker and the further modification of gold nanoparticles, the matrix has advantages of good hydrophilicity and enhanced surface area, which are beneficial to improve the enrichment selectivity and efficiency for glycoproteins. The attachment of MPBA and MPA provide intramolecular BN coordination, which could further enhance the specificity of glycoprotein capture. Such a boronate affinity monolith was applied to enrich horseradish peroxidase (HRP) from the mixture of HRP and bovine serum albumin (BSA), and high selectivity was obtained even at a mass ratio of 1:1000. In addition, the binding capacity of ovalbumin on such monolith reached 390 µg g(-1) . Furthermore, the average recovery of HRP on the prepared affinity monoliths was (84.8±1.9) %, obtained in three times enrichment with the same column. Finally, the boronate affinity monolith was successfully applied for the human-plasma glycoproteome analysis. As a result, 160 glycoproteins were credibly identified from 9 µg of human plasma, demonstrating the great potential of such a monolith for large-scale glycoproteome research.

Reinnervated nerves contribute to the secretion function and regeneration of denervated submandibular glands in rabbits.

This study aimed to investigate the contribution of redistributed nerves in the secretory function and regeneration of a denervated submandibular gland (SMG). The postganglionic parasympathetic and sympathetic denervated SMGs of rabbits were wrapped in polyester or acellular dermal matrices to block nerve regeneration either partially or completely. Submandibular glands were removed 4, 8, 16, and 24 wk after the operation and examined histologically. Furthermore, the aquaporin-5 (AQP5), muscarinic-3 (M3), and ß1-adrenergic receptors were evaluated by immunofluorescence and western blot analysis. After denervation, salivary flow was decreased and acinar cells were atrophic, and the expression levels of the M3, ß1-adrenergic, and AQP5 receptors were decreased. However, both impaired secretion function and atrophic parenchyma were gradually ameliorated with the growing redistribution of parasympathetic and sympathetic nerves. Apoptosis was markedly inhibited and expression of the M3, ß1-adrenergic, and AQP5 receptors was increased after reinnervation. In contrast, SMGs without reinnervated nerves maintained hyposecretion and atrophic parenchyma. In conclusion, reinnervated nerves in a rabbit's denervated SMG played an important role in the secretion function and regeneration of SMGs via up-regulation of the expression of neurotransmitter receptors and AQP5.

The trend of radiographic healing after root canal treatment in teeth with apical periodontitis based on cone-beam computed tomography: A 4-year longitudinal study.

OBJECTIVES: The aim of this study was to observe the radiographic healing of periapical lesions after root canal treatment via volumetric measurements based on cone-beam computed tomography (CBCT) over 4 years. METHODS: In total, 162 single-root teeth from patients with chronic periapical periodontitis who underwent primary root canal treatment were included in this retrospective study. Follow-up visits were scheduled at 1, 2, and 4 years after treatment. The volume of radiolucency at pretreatment and follow-up were measured, and the radiographic outcomes were classified into 4 categories: absence, reduction, uncertain or enlargement. Reduction or enlargement was considered when the volumetric change in radiolucency was 20 % or more. RESULTS: During the 4-year follow-up period, 128 teeth were reviewed at least once, including 3 extracted teeth. Of the remaining 125 teeth, the volume of radiolucency was reduced in 116 teeth (90.6 %), uncertain in 5, and enlarged in 4 teeth during 1 to 4 years after treatment. Among the 43 teeth with reduced radiolucency at 1 year after treatment, 42 (97.7 %) had continuing reduced lesions at 4 years. In the 2 teeth with enlarged radiolucency at 1 year, the volume of radiolucency doubled at 4 years. Cox regression analysis revealed that the preoperative radiolucency size was a risk factor for persistent periapical radiolucency. CONCLUSIONS: The efficacy of root canal treatment for apical periodontitis was predictable. When the radiolucency changed by 20 % or more in volume on CBCT scans at 1 year after treatment, reversal of the radiographic healing tendency was rare. CLINICAL SIGNIFICANCE: The volumetric changes in radiolucency on CBCT could reflect trends in the healing process and may foster early clinical decision-making.

Mechanical biomimetic silk nano fiber-magnesium ion complex/hydroxyethylcellulose/glycerol hydrogel dressing with angiogenic capacity for accelerating scarless diabetic wound healing.

Quick scarless healing remains a key issue for diabetic wounds. Here, a stretchable elastomeric hydrogel dressing composed of hydroxyethylcellulose (HEC), silk nano fiber-magnesium ion complex (Mg2+-SNF) and glycerol (Gly) was developed to optimize mechanical niche, anti-inflammatory and angiogenic behavior simultaneously. The composite hydrogel dressing exhibited skin-like elasticity (175.1 ± 23.9 %) and modulus (156.7 ± 2.5 KPa) while Mg2+-SNF complex endowed the dressing with angiogenesis, both favoring quick scarless skin regeneration. In vitro cell studies revealed that the hydrogel dressing stimulated fibroblast proliferation, endothelial cell migration and vessel-like tube formation, and also induced anti-inflammatory behavior of macrophages. In vivo results revealed accelerated healing of diabetic wounds. The improved granulation ingrowth and collagen deposition suggested high quality repair. Both thinner epidermal layer and low collagen I/III ratio of the regenerated skin confirmed scarless tissue formation. This bioactive hydrogel dressing has promising potential to address the multifaceted challenges of diabetic wound management.

Development of a zinc chloride-based chemo-mechanical system for potential minimally invasive dental caries removal system.

Background/purpose: The chemo-mechanical caries-removal technique is known to offer advantages of selective dentin caries treatment while leaving healthy dental tissues intact. However, current sodium hypochlorite based reagents usually excessively damage dentin collagen. Therefore, the purpose of this study was to develop a novel chemo-mechanical caries-removal system to preserve the collagen network for subsequent prosthetic restorations. Materials and methods: The calfskin-derived collagen was chosen as a model system to investigate the dissolution behavior of collagen under different operating conditions of chemical-ultrasonic treatment systems. The molecular weight, triple-helix structure, the morphology, and functional group of collagen after treatment were investigated. Results: Various concentrations of sodium hypochlorite or zinc chloride together with ultrasonic machinery were chosen to investigate. The outcomes of circular dichroism (CD) spectra demonstrated stability of the triple-helix structure after treatment of a zinc chloride solution. In addition, two apparent bands at molecular weights (MWs) of 130 and 121 kDa evidenced the stability of collagen network. The positive 222 nm and 195 nm negative CD absorption band indicated the existence of a triple-helix structure for type I collagen. The preservation of the morphology and functional group of the collagen network on the etched dentin surface were investigated by in vitro dentin decalcification model. Conclusion: Unlike NaOCl, the 5 wt% zinc chloride solution combined with ultra-sonication showed dissolution rather than denature as well as degradation of the dentin collagen network. Additional in vivo evaluations are needed to verify its usefulness in clinical applications.