Regional intra-arterial vs. systemic chemotherapy for the treatment of advanced pancreatic cancer: a systematic review and meta-analysis.

Introduction: Pancreatic cancer is a highly aggressive malignancy with limited response to chemotherapy. This research aims to compare the effectiveness and safety of regional intra-arterial chemotherapy (RIAC) with conventional systemic chemotherapy in treating advanced stages of pancreatic cancer. Methods: A comprehensive literature review was conducted using databases such as PubMed, Embase, Web of Science, and the Cochrane Library. Studies assessing the comparative outcomes of RIAC and systemic chemotherapy were included. Data extraction and quality evaluation were performed independently by two researchers. Statistical analysis was conducted using STATA16 software, calculating odds ratios (OR), risk differences (RD), and 95% confidence intervals (CI). Results: Eleven studies, comprising a total of 627 patients, were included in the meta-analysis. The findings showed that patients undergoing RIAC had significantly higher rates of partial remission (PR) compared to those receiving systemic chemotherapy (OR = 2.23, 95% CI: 1.57, 3.15, I2= 0%). Additionally, the rate of complications was lower in the RIAC group (OR = 0.45, 95% CI: 0.33, 0.63, I2= 0%). Moreover, patients treated with RIAC had notably longer median survival times. Discussion: The results of this research indicate that RIAC is associated with a higher rate of partial remission, improved clinical benefits, and fewer complications compared to systemic chemotherapy in the management of advanced pancreatic cancer. These findings suggest that RIAC may be a more effective and safer treatment option for patients with advanced stages of pancreatic cancer. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023404637.

A strategy for oral delivery of FGF21 for mitigating inflammation and multi-organ damage in sepsis.

Fibroblast growth factor 21 (FGF21) shows great therapeutic potential in metabolic, neurodegenerative and inflammatory diseases. However, current FGF21 administration predominantly relies on injection rather than oral ingestion due to its limited stability and activity post-gastrointestinal transit, thereby hindering its clinical utility. Milk-derived exosomes (mEx) have emerged as a promising vehicle for oral drug delivery due to their ability to maintain structural integrity in the gastrointestinal milieu. To address the challenge associated with oral delivery of FGF21, we encapsulated FGF21 within mEx (mEx@FGF21) to protect its activity post-oral administration. Additionally, we modified the surface of mEx@FGF21 by introducing transferrin (TF) to enhance intestinal absorption and transport, designated TF-mEx@FGF21. In vitro results demonstrated that the surface modification of TF promoted FGF21 internalization by intestinal epithelial cells. Orally administered TF-mEx@FGF21 showed promising therapeutic effects in septic mice. This study represents a practicable strategy for advancing the clinical application of oral FGF21 delivery.

Efferocytosis-Inspired Biomimetic Nanoplatform for Targeted Acute Lung Injury Therapy.

Acute lung injury (ALI) is a serious inflammatory disease that causes impairment of pulmonary function. Phenotypic modulation of macrophage in the lung using fibroblast growth factor 21 (FGF21) may be a potential strategy to alleviate lung inflammation. Consequently, achieving specific delivery of FGF21 to the inflamed lung and subsequent efficient FGF21 internalization by macrophages within the lung becomes critical for effective ALI treatment. Here, an apoptotic cell membrane-coated zirconium-based metal-organic framework UiO-66 is reported for precise pulmonary delivery of FGF21 (ACM@U-FGF21) whose design is inspired by the process of efferocytosis. ACM@U-FGF21 with apoptotic signals is recognized and internalized by phagocytes in the blood and macrophages in the lung, and then the intracellular ACM@U-FGF21 can inhibit the excessive secretion of pro-inflammatory cytokines by these cells to relieve the inflammation. Utilizing the homologous targeting properties inherited from the source cells and the spontaneous recruitment of immune cells to inflammatory sites, ACM@U-FGF21 can accumulate preferentially in the lung after injection. The results prove that ACM@U-FGF21 effectively reduces inflammatory damage to the lung by modulating lung macrophage polarization and suppressing the excessive secretion of pro-inflammatory cytokines by activated immune cells. This study demonstrates the usefulness of efferocytosis-inspired ACM@U-FGF21 in the treatment of ALI.

Articulation distortion in Mandarin-speaking individuals with complete arch maxillary implant-supported fixed dental prostheses.

STATEMENT OF PROBLEM: Implant-supported fixed dental prostheses (IFPs) have been increasingly used to restore edentulous jaws, yet few studies have utilized acoustic analysis for objective evaluation of postrestoration speech outcomes. PURPOSE: The purpose of this clinical study was to assess speech articulation in edentulous individuals before and after the provision of IFPs by combining the results of subjective evaluations and objective acoustic analysis parameters. MATERIAL AND METHODS: The study included thirty-four individuals who had an edentulous maxilla and had been provided with an IFP for over 6 months, along with 6 dentate controls. Acoustic analysis was conducted, and mean opinion scores (MOS) were rated from recordings. The participants were interviewed about perceived speech changes. Changes in the parameters were evaluated using the paired t test or Wilcoxon signed-rank test (α=.05). A comparison between dentate controls and edentulous individuals (with or without prostheses) was made using an independent t test or Mann-Whitney U test (α=.025). RESULTS: Following restoration, the center of gravity (CoG) changes occurred in 11 of 12 consonants in edentulous individuals (P<.05). Prosthesis use allowed the CoG of all affricates and fricatives to appear larger and closer to control values. Before restoration, the CoG of 9 of 12 consonants in edentulous individuals differed from controls (P<.01); after restoration, this reduced to 3 out of 12 (P<.01). MOS improved in 10 of 12 consonants (P<.01), nearing a score of 4. Despite restoration, the CoG of alveolo-palatals [tɕh], [tɕ], and [ɕ] remained different from controls (P<.01). Most participants were satisfied with the improvement, with few reporting discomfort with alveolars [s] and [tsh]. CONCLUSIONS: IFPs can enhance speech in edentulous individuals, yet articulation distortions of alveolar and alveolo-palatal consonants persist. The improper palatal shape of IFPs or an abrupt joint between the IFP and atrophic natural bone may contribute to these distortions.

RPL24 as a potential prognostic biomarker for cervical cancer treated by Cisplatin and concurrent chemoradiotherapy.

Cervical carcinoma (CC) is the one of most common gynecologic cancers worldwide. The ribosomal proteins (RPs) are essential for ribosome assembly and function, and it has been verified that the abnormal expression of RPs was closely associated with tumorigenesis. In this study, we found that the RP large subunit 24 (RPL24) expression level was upregulated after the CC cell lines SiHa and HeLa were treated with Cisplatin (CDDP) in vitro. Simultaneously, a nude mouse xenograft model was used to examine the effect of RPL24 on tumor growth in vivo, which showed that overexpression of RPL24 can suppress tumor growth. Furthermore, we proved that RPL24 expression increased after CC patients were treated with concurrent chemoradiotherapy (CCRT), and the higher expression of RPL24 predicted a better prognosis using clinical data from 40 CC patients, verified via the Kaplan-Meier Plotter and LOGpc. These results revealed that RPL24 can be considered a potential biomarker to predict the prognosis of CC patients and assess CCRT efficacy.

[Relationship between sICAM-1, IL-1ß and HIF-1α levels in gingival sulcus fluid and peri-implantitis in patients with implant restoration].

PURPOSE: To investigate the relationship between the levels of soluble intercellular adhesion molecule-1 (sICAM-1), interleukin-1ß (IL-1ß) and hypoxia-inducible factor-1α (HIF-1α) in gingival sulcus fluid and peri-implantitis (PI) in patients with implant restoration. METHODS: A total of 198 patients with implant restoration admitted to Fengcheng Hospital from January 2019 to December 2021 were selected, the patients were divided into PI and non-PI group according to whether the implant restoration was complicated by PI 3 months after restoration. The levels of sICAM-1, IL-1ß and HIF-1α in the gingival sulcus fluid prior to implant restoration were measured by enzyme-linked immunosorbent assay. Multi-factor logistic regression was used to analyze the factors influencing concurrent PI in patients with implant restoration. ROC curves were used to analyze the predictive value of sICAM-1, IL-1ß and HIF-1α levels in gingival sulcus fluid on concurrent PI in patients with implant restoration. SPSS 28.0 software package was used for statistical processing of the data. RESULTS: The incidence of PI in 198 patients with implant restoration was 17.68% (35/198) 3 months after implant restoration. The levels of sICAM-1, IL-1ß and HIF-1α in the gingival sulcus fluid were significantly higher in the PI group than in the non-PI group (P＜0.05). Multi-factor logistic regression analysis showed that elevated sICAM-1(OR=1.135, 95%CI: 1.066-1.208), IL-1ß (OR=1.106, 95%CI: 1.054-1.161) and HIF-1α (OR=1.008, 95%CI: 1.004-1.012) were independent risk factors for complications of PI in prosthetic patients(P＜0.05). ROC curve analysis showed that the area under the curve for sICAM-1, IL-1ß and HIF-1α levels in gingival sulcus fluid alone and in combination for the diagnosis of concurrent PI in patients with implantation was 0.787, 0.785, 0.794 and 0.930, respectively, with sensitivity of 80.00%, 74.29%, 62.86% and 88.57% and specificity of 66.87%, 74.85%, 78.53% and 85.28%, respectively. CONCLUSIONS: Elevated levels of sICAM-1, IL-1ß and HIF-1α in gingival sulcus fluid are independent risk factors for PI complications in patients with implant restoration and can be used as an auxiliary predictor of PI complications in patients with implant restoration.

[Study on the effect of alginate impression spray disinfection process on model accuracy].

PURPOSE: To investigate the effect of a new cleaning and disinfection process of oral impressions on the accuracy of alginate dental impression. METHODS: Sixteen young volunteers were selected to make alginate oral impression (2 times for each upper and lower jaw) and oral scandata acquisition (1 time for each upper and lower jaw) to obtain STL data. The 2 pairs of alginate impressions of each subject were numbered group 1, group 2, inwhich group 1 was not sterilized and the oral impression film in group 2 was treated with the method and steps of new oral impression cleaning and disinfection. All the oral impressions of the subjects were perfused with plaster models in the same standard way and demoulded. The obtained plaster models were examined and scanned after appropriate trimming and grinding. The plaster model data obtained from each group of each patient after warehouse scanning were compared with the orally scanned model data for alignment analysis, and root mean square(RMS) was used as a parameter to evaluate the deviation between the test model and the standard model. The chromatograms of the deviations were saved for visualization and analysis to observe the differences in model accuracy from several dimensions. Statistical analysis was performed with SPSS 23.0 software package. RESULTS: The differences in RMS of model accuracy of maxillary dental series of alginate impressions were statistically significant, in which the RMS of the group disinfecting the maxillary oral impression film with a new oral impression cleaning and disinfection process was significantly higher than that of the nonsterilized group (P=0.006), while the difference between model accuracy RMS of the mandibular disinfection group and non-disinfection group was not statistically significant(P=0.874). CONCLUSIONS: The new technical specifications for cleaning and disinfection of dental impressions recommended by the Chinese Stomatological Association have certain effects on the accuracy of dental impressions made of alginate material,and the details in its process should be further improved.

EFFECTS OF POST-EXTRACTION ALVEOLAR RIDGE PRESERVATION VERSUS IMMEDIATE IMPLANT PLACEMENT: A SYSTEMATIC REVIEW AND META-ANALYSIS.

OBJECTIVES: This systematic review aimed to compare the clinical data including success rates, tissue preservation, esthetic results, and patient-reported outcomes between delayed implant placement after alveolar ridge preservation (ARP) and immediate implant placement (IIP). MATERIAL AND METHODS: Both electronic and manual searches were performed for randomized controlled trials and cohort studies consisting of at least 10 cases per group and a follow-up of at least 1-year in duration. The primary outcome was the implant success rate and secondary outcomes were changes in marginal bone level (MBL), pink esthetic score (PES) and patient reported outcomes consisting of complications and satisfaction. RESULTS: A total of 12 studies were included (8 randomized controlled trials and 4 cohort studies). This review contained 456 implants placed after ARP and 459 implants placed through IIP. The results from this meta-analysis showed that the success rates of implants placed through ARP protocol (98.68%) was significantly higher than that of implants placed through IIP protocol (95.21%) (RR = 1.03; 95% CI [1.01; 1.06]; P = .008; I2 = 0%). CONCLUSION: The results from this meta-analysis and systematic review showed that implants placed through ARP protocol may demonstrate higher success rates compared to implants placed through IIP.

Primary implant stability based on alternative site preparation techniques: A systematic review and meta-analysis.

AIM: To evaluate the effect of special implant site preparation methods in improving primary implant stability in low-density bone. MATERIAL AND METHODS: This meta-analysis included studies published in English and Mandarin Chinese up to March 31, 2022 from MEDLINE/PubMed, Embase, Scopus, and Wanfang databases. The primary stability of five site preparation methods were measured using implant stability quotient. The random-effects model was chosen for data analysis. Grading of recommendations assessment, development, and evaluation assessment was adopted as a collective grading of the overall body of evidence. RESULTS: 12 of the 17 studies included in the meta-analysis were randomized control trials. Three studies investigated osseodensification drilling (OD), eight studies examined osteotome technique (OT), five studies explored piezosurgery (PS), and four studies were conducted on under-drilling (UD). Meta-analysis showed a statistically significant increase in primary stability for the OD (mean difference [MD], 10.25; 95% CI: 4.97-15.52; p < 0.001), OT (MD, 6.34; 95% CI: 2.26-10.42; p = 0.002), and UD (MD, 11.43; 95% CI: 5.17-17.68; p < 0.001) groups when compared to the conventional drilling group, while the PS group did not (MD, 1.50; 95% CI: -2.54-5.54; p = 0.47). CONCLUSION: Significantly higher primary implant stability was shown in the OD, UD, and OT groups compared to the conventional drilling group. PS displayed the least favorable primary stability and when compared to conventional drilling, was not statistically significant.

Investigation of material removal mechanisms and ductile-brittle transition zone of zirconia ceramics sintered at various temperatures.

Sintering is a comprehensive process that involves the complex evolution of material microstructures and properties, being recognized as a critical factor to improve the machinability of ceramics. The present work aims to address the evolution of the material removal mechanisms of the 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) during the sintering process based on the micro scratching tests. The impacts of sintering temperatures on the material removal behaviors, including scratching forces, scratch morphologies, specific scratching energies, and critical transition depths, were rigorously studied. The acquired results indicate that the intergranular bonding strength is a critical factor that determinines the material removal mechanisms of 3Y-TZP, and 1100 °C signifies the transition threshold for the material removal mode. After 1100 °C, the material removal mechanism has gradually converted into the typical ductile-brittle removal regime. Moreover, the critical depth in ductile regime at 1200 °C is about 1.89 times that at 1500 °C, and the critical depth of ductile-brittle transition at 1200 °C is approximately 2.08 times that at 1500 °C.

Correlation between esthetic expectations for orthognathic treatment and psychological characteristics among Chinese adult patients.

INTRODUCTION: This study aimed to evaluate the association of esthetic expectations with self-reported personal characteristics, anxiety, depression, self-esteem, oral health-related quality of life, and the Orthognathic Quality of Life Questionnaire (OQLQ) in Chinese adult patients before orthognathic treatment. METHODS: This study involved 213 patients with clinically significant skeletal deformity requiring orthognathic surgery for comprehensive treatment. Each patient completed a series of Chinese version scales, including the self-rating anxiety scale, self-rating depression scale, self-esteem scale, the Oral Health Impact Profile-14 questionnaire, and the OQLQ. The patients' self-reported personal characteristics were also recorded, including facial appearance ratings before and after orthognathic treatment, highest education level, mean monthly income, and enthusiasm toward orthodontic or orthognathic treatment. The Least Absolute Shrinkage and Selection Operator multivariate linear regression model was conducted for the selection of the above factors. The final multivariate linear regression model was built with variables identified under the optimal tuning parameter. RESULTS: A total of 213 patients (87 men and 126 women) were included in this study. The patients' esthetic expectation scores were significantly associated with their total scores, which encompassed the education level, mean monthly income, enthusiasm toward orthodontic or orthognathic treatment, self-esteem scale, the Chinese version of the 14-item Oral Health Impact Profile questionnaire, OQLQ, etc. In the multivariate linear regression model, the OQLQ, enthusiasm toward orthognathic treatment, depression, and expected facial appearance score after the treatment were the most important factors to predict esthetic expectation. CONCLUSIONS: High esthetic expectations for orthognathic treatment were mostly associated with higher expected facial appearance scores after the treatment, greater enthusiasm toward orthognathic treatment, worse depression (confusion), and 2 domains (social aspects of deformity and oral function) of OQLQ. Therefore, OQLQ, enthusiasm toward orthognathic treatment, and expected facial appearance score after treatment may be used to predict patients' esthetic expectations before commencing orthognathic treatment in daily clinical practice.

Associations of fine particulate matter and its constituents with airway inflammation, lung function, and buccal mucosa microbiota in children.

BACKGROUND: Previous studies have suggested acute effects of ambient fine particulate matter (PM2.5) air pollution on respiratory health among children, but evidence for PM2.5 constituents and respiratory health were still limited. OBJECTIVES: To investigate associations of short-term exposure to PM2.5 and its constituents with airway inflammation, lung function, and airway microbiota in children. METHODS: We conducted a longitudinal panel study with 3 repeated health measurements among 62 children in Shanghai, China from November 2018 to June 2019. Respiratory health was measured by fractional exhaled nitric oxide (FeNO), saliva tumor necrosis factor-α (TNF-α), lung function (forced vital capacity and forced exhaled volume in 1 s), and microbiota diversity in buccal mucosa samples. Based on the linear mixed-effect models, we applied the single-constituent models and the constituent-PM2.5 adjustment models to examine the associations between PM2.5 constituents and health outcomes. RESULT: Short-term exposure to PM2.5 was associated with higher TNF-α, FeNO levels and reduced lung function. Among all constituents, organic carbon, elemental carbon, NO3- and NH4+ had the consistent and strongest associations with airway inflammation biomarkers and lung function parameters, followed by metallic elements. We also found short-term PM2.5 exposure was associated with decreased diversity in buccal mucosa bacterial community and two bacterial phyla, Fusobacteria and Proteobacteria, were identified as differential microbes with PM2.5 exposure. CONCLUSION: Short-term exposure to PM2.5 may impair children's respiratory health represented by higher airway inflammation, lower lung function and altered buccal mucosa microbial colonization. Organic carbon, elemental carbon, NO3- and NH4+ may dominate these effects.

Exposure to ultrafine particles and oral flora, respiratory function, and biomarkers of inflammation: A panel study in children.

Particulate matter (PM) is the most important air pollution problem that leads to substantial health effects. However, very few studies focused on the effects of ultrafine particles (UFPs, particles< 0.1 µm) on children respiratory health. We performed a panel study with 3 rounds of follow-up among 65 pupils at the Elementary School Affiliated to Shanghai Normal University in China from November 2018 to June 2019. Real-time concentrations of UFPs were measured in the campus. In each visit, we detected biomarkers in saliva and microflora in buccal mucosa, fractional exhaled nitric oxide (FeNO) and lung function. We applied a linear mixed-effect (LME) model to examine the associations of UFPs and each health outcome. We found increased levels of FeNO and tumor necrosis factor-α (TNF-α) and reduced lung function in association with higher UFP exposure. For each interquartile range increase of UFPs, the largest changes were found in lag 0-72 h for forced vital capacity [-69.02 ml (95% CI: -114.20, -23.84)], TNF-α [13.41 pg/ml (95% CI: 7.08, 19.73)], and FeNO [26.85% (95% CI: 11.84%, 43.88%)]. UFP exposure was associated with reduced diversity in buccal microflora with largest reduction in lag 0-72 h [12.24 (95% CI: 7.76, 16.71) for Ace index; 8.78 (95% CI: 2.96, 14.60) for Chao1 index]. UFP exposure was also associated with increased Streptococcus, Gemella, and decreased Actinomyces. Short-term UFP exposures may impair the respiratory system by inducing inflammation, decreasing lung function and attenuating buccal microbe diversity in children.

[A comparative study of silicon rubber impression and intraoral scanning impression in oral clinical teaching].

PURPOSE: The aim of this study was to assess and compare patient satisfaction and time required between silicon rubber impression and intraoral scanning impression. METHODS: Six undergraduates participated in this study. silicon rubber impression and intraoral scanning impression were taken, the time required to obtain the impressions and the scores of visual analog scale(VAS) were recorded. SPSS 23.0 software package was used for statistical analysis. RESULTS: The time and patients satisfaction of silicon rubber impression were better than intraoral scanning impressions, and there were significant differences between the two groups(P<0.05). CONCLUSIONS: Using silicon rubber impression, the patient experience is better. To use intraoral scanning impression technology, dentists should be more skilled. With the role-playing method,dental interns can learn the operation key points and precautions of different impression-taking methods even better.

Glucose-coated Berberine Nanodrug for Glioma Therapy through Mitochondrial Pathway.

INTRODUCTION: Glioma is the primary malignant brain tumor with poor prognosis. Berberine (BBR) was the potential drug for anti-tumor in glioma cells. Based on its limitation of poor aqueous solubility and instability, little information of BBR nanoparticles is reported in glioma. METHODS: Different solutions including 5% glucose, 1*PBS, ddH2O, 0.9% NaCl, cell culture medium were selected, and only 5% glucose and ddH2O exhibited BBR-related nanoparticles. After heating for a longer time or adding a higher concentration of glucose solution, BBR nanoparticles were detected by TEM analysis. The uptake of BBR-Glu or BBR-Water nanoparticles were detected by immunofluorescence analysis for BBR autofluorescence. Cell viability was measured by MTT assay and Western blotting analysis. Apoptosis was performed with flow cytometric analysis and was detected by cleaved caspase-3 immuno-fluorescent staining. Cell cycle was used by flow cytometric analysis. Cytoskeleton was observed by confocal analysis using the neuron specific Class III ß-tubulin and ß-tubulin antibodies. Mitochondrial-related proteins were detected by Western blotting analyses and mito-tracker staining in live cells. Mitochondrion structures were observed by TEM analysis. ROS generation and ATP production were detected by related commercial kits. The tracking of BBR-Glu or BBR-Water nanoparticles into blood-brain barrier was observed in primary tumor-bearing models. The fluorescence of BBR was detected by confocal analyses in brains and gliomas. RESULTS: BBR-Glu nanoparticles became more homogenized and smaller with dose- and time-dependent manners. BBR-Glu nanoparticles were easily absorbed in glioma cells. The IC50 of BBR-Glu in U87 and U251 was far lower than that of BBR-Water. BBR-Glu performed better cytotoxicity, with higher G2/M phase arrest, decreased cell viability by targeting mitochondrion. In primary U87 glioma-bearing mice, BBR-Glu exhibited better imaging in brains and gliomas, indicating that more BBR moved across the blood-brain tumor barrier. DISCUSSION: BBR-Glu nanoparticles have better solubility and stability, providing a promising strategy in glioma precision treatment.

Automatic robot-world calibration in an optical-navigated surgical robot system and its application for oral implant placement.

PURPOSE: Robot-world calibration, used to precisely determine the spatial relation between optical tracker and robot, is regarded as an essential step for optical-navigated surgical robot system to improve the surgical accuracy. However, these methods are complicated with numerous computation. Therefore, a more efficient method of a robot-world calibration is necessary. METHODS: A fully automatic robot-world calibration was proposed and applied in a surgical robot system for oral implant placement. Making full usage of the movement characteristics of a tandem robot, the least square fitting algorithm was implemented to calculate the relationship between the tool center point of the robot and the robot reference frame, with the robot-world calibration matrix obtained as result. RESULTS: The experiment was designed to verify the accuracy of the robot-world calibration. The average distance deviation was 1.11 mm, and the average angle deviation was 0.99°. From the animal experiment on the pig maxilla, the entry, apical and angle deviation of the surgical robot system were 1.44 ± 1.01 mm, 1.68 ± 0.76 mm, 1.01 ± 1.06°, respectively. CONCLUSION: The surgical robot system for oral implant placement with our robot-world calibration maintains a high precision. Besides, the operation range of the surgical tool is no longer limited by the visual range of the optical tracking device. Hence, it is unnecessary to adjust the optical tracking device for the planned implant trajectories to different positions and directions.

Dose Effects of Slow-Released Bone Morphogenetic Protein-2 Functionalized ß-Tricalcium Phosphate in Repairing Critical-Sized Bone Defects.

The aim of this study is to investigate the efficacy and the effect of the dosage of the slow-released Escherichia coli-derived recombinant human bone morphogenetic protein 2 (ErhBMP-2) functionalized ß-tricalcium phosphate (ß-TCP) in repairing critical-sized bone defects. The functionalization was implemented by modifying the surface of ß-TCP with biomimetic calcium phosphate coating with or without ErhBMP-2. Critical-sized calvarial defects were created in rats and filled with ErhBMP-2 functionalized ß-TCP loaded with gradient doses of ErhBMP-2 (0, 50, 100, 150, 200, and 300 µg/g). The blank control group and the autologous bone group were also included. The systemic toxicity was evaluated using routine blood and histopathological examination. The efficiency in bone healing was evaluated using microcomputed tomography, histology, and histometric analyses. Neither local nor systemic adverse effects were found following the implantation of the ErhBMP-2 functionalized ß-TCP. The new bone formation was significantly increased in the ErhBMP-2 functionalized ß-TCP groups compared with the blank group and the ß-TCP with coating only group. The efficacy of the ErhBMP-2 functionalized ß-TCP in bone healing was comparable to that of the autologous bone. There was no significant difference in bone formation among all concentrations of ErhBMP-2 (0-300 µg/g). Increased bone maturation was found in the higher concentration groups (150, 200, and 300 µg/g) when compared with the lower concentration groups (50, and 100 µg/g). Our results demonstrated that the ErhBMP-2 functionalized ß-TCP could significantly promote bone repairing in critical-sized defects, and it could clinically be a promising substitute for autologous bone. Besides, our results demonstrated that there was a dosage-dependent effect of ErhBMP-2 functionalized ß-TCP on bone maturation rather than bone formation. The optimized concentrations of ErhBMP-2 recommended for this kind of model should be in the range of 150-300 µg/g. Impact Statement Bone substitutes functionalized by mammalian-derived recombinant human bone morphogenetic protein 2 (rhBMP-2) have demonstrated to be comparable to the autologous bone in repairing the critical-sized bone defects. To develop a commercial product with more effective cost, Escherichia coli-derived rhBMP-2 (ErhBMP-2) has been produced and evaluated as an alternative to the mammalian-derived rhBMP-2. In this study, we prepared gradient ErhBMP-2 functionalized ß-tricalcium phosphate (ß-TCP) with biomimetic calcium phosphate coating and investigate their efficacy and dose effects. We revealed the dose effects of the slow-released ErhBMP-2 and demonstrated that ErhBMP-2 functionalized ß-TCP could be a promising bone substitute for bone regeneration in clinical settings.

Pilot study of a surgical robot system for zygomatic implant placement.

Zygomatic implant technology has been regarded as an alternative treatment to massive grafting surgery in the severe atrophic maxillary. Nowadays, the assistant method with a real-time surgical navigation has been applied to reduce the risks of zygomatic implant placement. However, the accuracy of the complex operation is highly dependent on the experience of the surgeon. In order to avoid disadvantages of traditional surgical navigation systems, a novel surgical robot system for the zygomatic implant placement has been designed and developed. Firstly, the drilling trajectory of the zygomatic implant placement is designed through the pre-operative planning system. Secondly, the real-time positions of the surgical instruments are constantly updated with the guidance of the optical tracker. Finally, through a coordinate transformation algorithm, the drilling performance can be conducted with the control of a six degree of freedom robot. In order to evaluate the accuracy of the robot, phantom experiments had been carried out. The angle, entry point and exit point deviation of the robotic system are 1.52 ±â€¯0.58°, 0.79 ±â€¯0.19 mm, and 1.49 ±â€¯0.48 mm, respectively. Meanwhile, a comparison between the robotic and manual operation demonstrates that the use of the surgical robot system for the zygomatic implant placement can improve the accuracy of the operation.

Measurement and prediction of drilling force in fresh human cadaver mandibles: A pilot study.

BACKGROUND: Bone drilling is a vital procedure in implant surgery and dental implant training systems based on virtual reality technology. PURPOSE: Predict and update drilling force in real time based on a virtual dental implant training system and lay the foundation for realizing force feedback in dental implant training instruments. MATERIALS AND METHODS: An experimental platform was established to measure the drilling force for human mandibles from donors of different ages. Response surface methodology was applied to analyze the drilling force. RESULTS: Force regression equations for different age groups were acquired. The order of the effects (from greatest to least) of the drilling parameters on the drilling force was the drill bit diameter, feed rate, and rotational speed. To obtain the minimum force, higher rotational speeds, lower feed rates, and smaller diameters were preferred within the range of commonly used medical reference parameters of bone drilling. CONCLUSION: The experimental data were confirmed to be scientific for the predicted models of drilling force.

Vertical bone augmentation with simultaneous implantation using deproteinized bovine bone block functionalized with a slow delivery of BMP-2.

OBJECTIVE: We hypothesized that a biomimetic calcium phosphate (CaP) coating which incorporates morphogenetic protein 2 (BMP-2) on the deproteinized bovine bone (DBB) blocks could be used to enhance the vertical alveolar ridge augmentation for the one-stage onlay surgery with simultaneous implants insertion. We aimed to test this hypothesis in vivo. MATERIAL AND METHODS: Beagles dogs were used for the study (n = 6 specimens per group). One month after building the edentulous animal model, 4 mm vertical alveolar bone loss were surgically created and four groups of blocks (W × L × H: 7 mm × 10 mm × 4 mm) were randomly fixed onto the reduced alveolar ridge by implants: (a) DBB blocks alone (negative control group); (b) DBB blocks with superficial adsorption of 50 µg BMP-2 (ad.BMP-2 group); (c) DBB blocks coated by biomimetic CaP coating which incorporates 50 µg BMP-2 (inc.BMP-2 group); and (d) autologous bone blocks (positive control group). After 3 months of healing, samples were harvested for micro-CT and histomorphometric analyses. RESULTS: In histomorphometry, the inc.BMP-2 group showed a significantly thicker (coronal-apically) and wider (buccal-lingually) augmented bone area, better bone-to-implant contact than the negative control group. In both the micro-CT and histomorphometry, the inc.BMP-2 group showed more mineralized tissue than the negative control group and the inc.BMP-2 group also showed significantly more newly formed bone and residual grafts than the negative control group in the upper half of the blocks. In micro-CT, the inc.BMP-2 group showed significantly more bone-to-graft contact percentage than the ad.BMP-2 group. In both micro-CT and histomorphometry, the inc.BMP-2 group showed significantly more percentage of mineralized tissue than the ad.BMP-2 group. No significant differences were found between the inc.BMP-2 group and the positive control group either in micro-CT or in histomorphometry. CONCLUSIONS: The DBB blocks with coating-delivered BMP-2 significantly enhanced the efficacy of vertical alveolar bone augmentation, compared with the unloaded blocks and blocks with adsorbed BMP-2, in the one-stage onlay surgery with simultaneous implant insertion.