Real-time detection of SARS-CoV-2 in clinical samples via ultrafast ligation-dependent RNA transcription amplification.

RNA has been recognized as an important biomarker of many infectious pathogens; thus, sensitive, simple and rapid detection of RNA is urgently required for the control of epidemics. Herein, we report an ultrafast ligation-dependent RNA transcription amplification assay with high sensitivity and specificity for real-time detection of SARS-CoV-2 in real clinical samples, termed splint-based cascade transcription amplification (SCAN). Target RNA is first recognized by two DNA probes, which are then ligated together by SplintR, followed by the binding of the T7 promotor and T7 RNA polymerase to the ligated probe and the start of the transcription process. By introducing a vesicular stomatitis virus (VSV) terminator in the ligated probe, large amounts of RNA transcripts are rapidly produced within 10 min, which then directly hybridize with molecular beacons (MBs) and trigger the conformational switch of the MBs to generate a fluorescence signal that can be monitored in real time. The SCAN assay, which can be completed within 30-50 min, has a limit of detection of 104 copies per mL, while exhibiting high specificity to distinguish the target pathogen from those causing similar syndromes. More importantly, the results of SCAN for SARS-CoV-2 detection in clinical samples display great agreement with the most used qRT-PCR and qRT-LAMP, indicating great potential in the diagnosis of pathogens in clinical practice.

Combination of Cetylpyridinium Chloride and Chlorhexidine Acetate: A Promising Candidate for Rapid Killing of Gram-Positive/Gram-Negative Bacteria and Fungi.

Combined use of the present antimicrobial drugs has been proved to be an alternative approach for antimicrobial agents' development since the co-existed of the drugs working in different mechanism have been demonstrated potentially enhance their antimicrobial activity. In this work, antibacterial and antifungal activity of the cetylpyridinium chloride (CPC)/chlorhexidine acetate (CHA) combination was evaluated for the first time, while a universal concentration for the rapid killing of gram-positive/gram-negative bacteria and fungi was also proposed. The minimum inhibitory concentrations (MIC) of CPC and CHA used alone or in combination were first measured, showing that the combined treatment decreased the MIC against tested gram-positive/gram-negative bacteria and fungi to 1/8-1/2. Growth curve assays demonstrated CPC and CHA had dynamic combined effects against the tested microorganisms at the concentration equal to MIC. Besides, combined use of these two drugs could also enhance their biocidal activity, which was illustrated by fluorescence microscopy and SEM images, as well as soluble protein measurement. More importantly, in vitro acute eye and skin irritation tests showed short-term contact with CPC/CHA combination would not cause any damage to mammalian mucosa and skin. In a word, CPC/CHA combination exhibited broad-spectrum antibacterial and antifungal activity against tested gram-positive/gram-negative bacteria and fungi while without any acute irritation to mammalian mucosa and skin, providing a new perspective on the selection of personal disinfectants.

Incidence rate of angel wing and its effect on wing bone development and serum biochemical parameters in geese.

The first purpose of this study was to reveal the distribution of the angel wing (AW) of geese. Our data showed that the total incidence of AW was 6.67% in 150-day-old White Zhedong (ZD) geese, the occurrence of AW in left wing is higher than that in right wing and bilateral wing than unilateral wing (both P < 0.01). In 70-day-old Hybrid-Wanxi (HW) geese, the total incidence of AW was 8.86%, with similar incidence rate between unilateral and bilateral. The sex has not apparently affected the incidence of AW in both ZD and HW geese. To explore the potential relationship between wing type with body weight, organ index, bone characteristic, or blood biochemical parameters in 70-day-old HW geese. We found that the body weight and organ index were similar between normal wing (NW) and AW geese. The length for the humerus, metacarpal and phalanx, and the phalanx weights, as well as the angle between the humerus and the radial ulna (HRU) in NW geese were pronounced greater than that in AW geese (P < 0.05). Furthermore, the angel wing was strongly associated with lower platelet size indicators. Collectively, AW affected the wing bone length, phalanx weight, and HRU, and the occurrence of AW may be related with dysfunctional platelet activation in geese.

Tideglusib suppresses stem-cell-like features and progression of osteosarcoma by inhibiting GSK-3ß/NOTCH1 signaling.

Osteosarcoma is the most common primary bone tumor in children, teenagers and adolescents. Cancer stem cells (CSCs) have the function to self-renew and keep the phenotype of tumor, causing clinical treatment failure. Therefore, developing effective therapies to inhibit osteosarcoma progression is urgently necessary. Glycogen synthase kinase 3ß (GSK-3ß)is highly expressed in osteosarcoma. In the present study, we made an exploration on the anti-tumor effect of tideglusib (TID), a small-molecule inhibitor of GSK-3ß, and revealed the underlying mechanisms. Here, we found that TID markedly reduced the cell viability of different osteosarcoma cell lines. Cell cycle arrest distributed in G2/M was markedly up-regulated in TID-incubated osteosarcoma cells through enhancing p21 expression levels. Apoptosis was evidently induced in osteosarcoma cells via blocking Caspase-3 activation. Consistently, tumor growth was effectively suppressed in an established murine xenograft model with few toxicity and side effects in vivo. Furthermore, TID markedly repressed stem-cell-like activity in osteosarcoma cells through down-regulating NOTCH1 expression. Notably, rescuing NOTCH1 significantly abolished the role of TID in reducing cell proliferation and sarcosphere-formation. Mechanistically, we found that TID-inhibited NOTCH1 expression was associated with the blockage of AKT/GSK-3ß signaling pathway. In summary, we for the first time provided evidence that TID could effectively inhibit osteosarcoma progression through repressing cell proliferation, inducing apoptosis, suppressing stem-cell-like properties via down-regulating AKT/GSK-3ß/NOTCH1 signaling pathway. Thus, TID may be a promising therapeutic strategy for osteosarcoma treatment without side effects.

Long non-coding RNA TTN antisense RNA 1 facilitates hepatocellular carcinoma progression via regulating miR-139-5p/SPOCK1 axis.

Reportedly, long non-coding RNAs (lncRNAs) are implicated in hepatocellular carcinoma (HCC) progression, yet little is known concerning the biological functions of TTN antisense RNA 1 (TTN-AS1) in HCC. In this study, quantitative real-time polymerase chain reaction (qRT-PCR) was performed for detecting TTN-AS1, SPOCK1 mRNA, and miR-139-5p expressions in HCC cells and tissues. After TTN-AS1 was overexpressed or knocked down in HCC cells, CCK-8 and 5-Ethynyl-2'-deoxyuridine (EdU) assays were carried out for examining cell multiplication. Transwell assays were conducted for evaluating HCC cell migration and invasion. Dual-luciferase reporter assay was employed for verifying the binding relationships between miR-139-5p and TTN-AS1, and between SPOCK1 3'UTR and miR-139-5p. Western blot was employed to measure SPOCK1, E-cadherin, N-cadherin, and Vimentin protein expressions. We demonstrated that, TTN-AS1 and SPOCK1 expression levels were remarkably enhanced in HCC cells and tissues, whereas miR-139-5p expression was observably reduced. Functional experiments suggested that TTN-AS1 knockdown markedly repressed HCC cell multiplication, migration, epithelial-mesenchymal transition (EMT), and invasion. In addition, TTN-AS1 interacted with miR-139-5p and decreased its expression. Moreover, SPOCK1 was a miR-139-5p target, and miR-139-5p inhibitors were able to reverse TTN-AS1 knockdown-induced inhibitory effect on SPOCK1 expression. SPOCK1 overexpression plasmid could counteract TTN-AS1 knockdown-induced inhibiting impact on HCC cell multiplication, migration, invasion, and EMT. In conclusion, TTN-AS1 expression level is remarkably enhanced in HCC, and TTN-AS1 can promote the multiplication, migration, invasion, and EMT of HCC cells via regulating miR-139-5p/SPOCK1 axis.

Dynamic changes of blood glucose, serum biochemical parameters and gene expression in response to exogenous insulin in Arbor Acres broilers and Silky fowls.

Silky chicken is a breed of chickens with black skin and slow growth rate used in Chinese traditional medicine, whereas Arbor Acres broiler is a well-known commercial breed in the poultry industry, it is featured by a large size, rapid-growth rate, high feed-conversion rate and strong adaptability. The difference in their rate of growth may be primarily related to different mechanism for glucose metabolism. Here we compared the insulin sensitivity of the two breeds; we investigated the temporal changes (at 0 min, 120 min and 240 min) of serum insulin and other biochemical parameters and determined the spatio-temporal changes of gene mRNA abundance in response to exogenous insulin (80 µg/kg body weight). The results indicated that: (1) Silky chickens showed stronger blood glucose recovery than broilers in the insulin resistance test. (2) The serum urea level in Silky chickens was twice of broilers; exogenous insulin significantly up-regulated serum uric acid level in Silky fowls in a time-dependent manner and increased serum cholesterol content at 120 min. (3) Two breeds showed distinctly different temporal changed in serum insulin in response to exogenous insulin stimulation. The fasting serum insulin concentration of broilers was three-fold of Silky chickens at the basal state; it decreased significantly after insulin injection and the levels at 120 min and 240 min of broilers were only 23% (P < 0.01) and 14% (P < 0.01) of the basal state, respectively. Whereas the serum insulin content in Silky chickens showed stronger recovery, and the 240 min level was close to the 0 min level. (4) GLUT2, GLUT12, neuropeptide Y and insulin receptor (IR) were predominantly expressed in the liver, pectoralis major, olfactory bulb and pancreas, respectively, where these genes presented stronger insulin sensitivity. In addition, the IR mRNA level was strongly positively with the GLUT12 level. In conclusion, our findings suggested that Silky chickens have a stronger ability to regulate glucose homeostasis than broilers, owing to their higher IR levels in the basal state, stronger serum insulin homeostasis and candidate genes functioning primarily in their predominantly expressed tissue in response to exogenous insulin.

The distinct spatiotemporal distribution and effect of feed restriction on mtDNA copy number in broilers.

Mitochondrial DNA (mtDNA) copy number reflects the abundance of mitochondria in cells and is dependent on the energy requirements of tissues. We hypothesized that the mtDNA copy number in poultry may change with age and tissue, and feed restriction may affect the growth and health of poultry by changing mtDNA content in a tissue-specific pattern. TaqMan real-time PCR was used to quantify mtDNA copy number using three different segments of the mitochondrial genome (D-loop, ATP6, and ND6) relative to the nuclear single-copy preproglucagon gene (GCG). The effect of sex, age, and dietary restriction (quantitative, energy, and protein restriction) on mtDNA copy number variation in the tissues of broilers was investigated. We found that mtDNA copy number varied among tissues (P < 0.01) and presented a distinct change in spatiotemporal pattern. After hatching, the number of mtDNA copies significantly decreased with age in the liver and increased in muscle tissues, including heart, pectoralis, and leg muscles. Newborn broilers (unfed) and embryos (E 11 and E 17) had similar mtDNA contents in muscle tissues. Among 42 d broilers, females had a higher mtDNA copy number than males in the tissues examined. Feed restriction (8-21 d) significantly reduced the body weight but did not significantly change the mtDNA copy number of 21 d broilers. After three weeks of compensatory growth (22-42 d), only the body weight of broilers with a quantitatively restricted diet remained significantly lower than that of broilers in the control group (P < 0.05), while any type of early feed restriction significantly reduced the mtDNA copy number in muscle tissues of 42 d broilers. In summary, the mtDNA copy number of broilers was regulated in a tissue- and age-specific manner. A similar pattern of spatiotemporal change in response to early feed restriction was found in the mtDNA content of muscle tissues, including cardiac and skeletal muscle, whereas liver mtDNA content changed differently with age and dietary restriction. It seems that early restrictions in feed could effectively lower the mtDNA content in muscle cells to reduce the tissue overload in broilers at 42 d to some degree.

IGF2BP1 promotes LPS-induced NFκB activation and pro-inflammatory cytokines production in human macrophages and monocytes.

BACKGROUND: Lipopolysaccharide (LPS)-induced macrophage/monocyte activation and pro-inflammatory cytokines production are important mediators for periodontitis progression. The current study tested the potential role of insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) in the process. METHODS: THP-1 human macrophages and primary human peripheral blood mononuclear cells (PBMCs) were treated with LPS. mRNA and protein expression of IGF2BP1 were tested by qPCR and Western blotting assay. IGF2BP1 expression was altered by shRNAs or CRISPR/Cas-9 gene editing methods. LPS-induced cytokine production was tested by ELISA assay. Cytokine mRNA expression was tested by the quantitative real-time reverse transcriptase polymerase chain reaction (qPCR) assay. RESULTS: In THP-1 human macrophages and PBMCs, treatment with LPS induced mRNA and protein expression of IGF2BP1. IGF2BP1 silencing (by targeted shRNAs) or CRISPR/Cas-9 knockout largely inhibited LPS-induced production of multiple pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß and IL-6. Conversely, forced over-expression of IGF2BP1 facilitated LPS-induced pro-inflammatory cytokines production in THP-1 cells. For the mechanism study, we show that IGF2BP1 co-immunoprecipitated with p65-p52 nuclear factor kappa B (NFκB) complex in nuclei of LPS-treated THP-1 cells. Significantly, LPS-induced p65-p52 nuclear translocation and NFκB activation were inhibited by IGF2BP1 silencing or CRISPR/Cas-9 knockout. CONCLUSION: IGF2BP1 promotes LPS-induced NFκB signalling and transcriptional activation in human macrophages and monocytes.

The Efficacy and Safety of Miconazole Nitrate Mucoadhesive Tablets versus Itraconazole Capsules in the Treatment of Oral Candidiasis: An Open-Label, Randomized, Multicenter Trial.

BACKGROUND: Oral candidiasis (OC) is a common oral fungal infection. Recently, miconazole mucoadhesive tablets have been gaining attention for OC treatment. Despite trials in patients with human immunodeficiency virus and cancer, evidence of its application in the large-scale, general population with OC is lacking. This study aimed to evaluate the efficacy and safety of miconazole nitrate mucoadhesive tablets in comparison with itraconazole capsules for OC treatment. METHODS: The study was a randomized, open-label, parallel-armed, multicenter clinical trial. Totally, 343 patients diagnosed with OC, who met the inclusion criteria, were randomly assigned to either a treatment group that received miconazole nitrate mucoadhesive tablets (10 mg) once daily or a control group that received itraconazole capsules (100 mg QD) for 2 weeks, and were followed up for 2 weeks. The clinical cure, improvement of clinical symptoms/signs, mycologic cure, and safety were evaluated. RESULTS: The mucoadhesive tablets (n = 171) did not show inferiority to itraconazole (n = 172) in the treatment of OC. At the end of the 14-day treatment, the clinical cure rates were 45.29% and 41.76% in the miconazole and itraconazole groups, respectively (P = 0.3472). At the end of the 14-day follow-up, the clinical cure rates were 51.18% and 41.76% in the miconazole and itraconazole groups, respectively (P = 0.0329). Adverse events occurred in 53 subjects (33 in the miconazole group and 20 in the itraconazole group). There was no statistical difference in the safety profile between miconazole and itraconazole (P = 0.0533). Thrombocytopenic purpura, although rare, occurred in one patient in the miconazole group and was considered a drug-related, severe adverse event. CONCLUSION: Miconazole nitrate mucoadhesive tablets may be as effective as systemic itraconazole capsule for OC treatment. Physicians should be cautious about thrombocytopenic purpura occurring as a rare and serious adverse event of miconazole nitrate. TRIAL REGISTRATION: Chinese Clinical Trial Register ChiCTR-TRC-13003935.

Influence of Trabecular Bone on Peri-Implant Stress and Strain Based on Micro-CT Finite Element Modeling of Beagle Dog.

The objective of this investigation is to analyze the influence of trabecular microstructure modeling on the biomechanical distribution of the implant-bone interface. Two three-dimensional finite element mandible models, one with trabecular microstructure (a refined model) and one with macrostructure (a simplified model), were built. The values of equivalent stress at the implant-bone interface in the refined model increased compared with those of the simplified model and strain on the contrary. The distributions of stress and strain were more uniform in the refined model of trabecular microstructure, in which stress and strain were mainly concentrated in trabecular bone. It was concluded that simulation of trabecular bone microstructure had a significant effect on the distribution of stress and strain at the implant-bone interface. These results suggest that trabecular structures could disperse stress and strain and serve as load buffers.

Non-joint effusion is associated with osteoarthritis in temporomandibular joints with disk displacement.

PURPOSE: The aim of this study was to examine the possible association between different grades of joint effusion (JE) and osteoarthritis (OA) in temporomandibular joint (TMJ) anterior disk displacement without reduction (ADDwoR). MATERIAL AND METHODS: A sample of 101 female patients 20-40 years of age with unilateral TMJ ADDwoR were retrospectively reviewed. JE and OA were diagnosed with magnetic resonance imaging (MRI). JE was subdivided into three different grades: grade 0, no or minimal effusion; grade 1, moderate effusion; and grade 2, extensive effusion. Eight categories of degenerative changes were used for screening for the existence of OA. Cases with no less than one type of degenerative change were diagnosed as OA. RESULTS: In all, 71 patients (70.3%) were diagnosed as having OA in the joints with disk displacement. In the univariate analysis, the proportion of subjects with non-JE (grade 0) was higher in the OA group (p = 0.003), while the proportion of subjects with extensive effusion (grade 2) was lower in the OA group (p = 0.02). In the multivariate logistic regression analysis, non-JE was independently associated with the development of OA (odds ratio = 5.68, 95% confidence interval = 1.10-29.37, P = 0.04). CONCLUSION: The results suggested that non-JE was associated with OA in the joints with ADDwoR.

Influence of orthotropy on biomechanics of peri-implant bone in complete mandible model with full dentition.

OBJECTIVE: The study was to investigate the impact of orthotropic material on the biomechanics of dental implant, based on a detailed mandible with high geometric and mechanical similarity. MATERIALS AND METHODS: Multiple data sources were used to elaborate detailed biological structures and implant CAD models. In addition, an extended orthotropic material assignment methodology based on harmonic fields was used to handle the alveolar ridge region to generate compatible orthotropic fields. The influence of orthotropic material was compared with the commonly used isotropic model and simplified orthotropic model. RESULTS: The simulation results showed that the values of stress and strain on the implant-bone interface almost increased in the orthotropic model compared to the isotropic case, especially for the cancellous bone. However, the local stress concentration was more obvious in the isotropic case compared to that in orthotropic case. The simple orthotropic model revealed irregular stress and strain distribution, compared to the isotropic model and the real orthotropic model. The influence of orthotropy was little on the implant, periodontal ligament, tooth enamel, and dentin. CONCLUSION: The orthotropic material has significant effect on stress and strain of implant-bone interface in the mandible, compared with the isotropic simulation. Real orthotropic mechanical properties of mandible should be emphasized in biomechanical studies of dental implants.

Chronological changes in the microstructure of bone during peri-implant healing: a microcomputed tomographic evaluation.

Our objectives were to examine the titanium-bone interfaces chronologically and to clarify the process of osseointegration using microcomputed tomography (microCT). The mandibular premolars of 3 dogs were extracted and 12 weeks later 2 Straumann dental implants were installed in each quadrant. The microstructural changes at the bone-implant interface at the first, fourth, and eighth weeks after installation were evaluated by microCT and a 3-dimensional image was constructed. The microstructural measurements at the bone-implant interface, including the trabecular number (Tb.N), bone volume fraction (BV/TV), structure model index (SMI), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp) and connectivity density (Conn.D), were measured. Experimental outcomes were analysed for correlations between time and microstructural variables of trabecular bone. Tb.N increased significantly during the eighth week compared with that during the first and fourth week (p=0.001, 0.002). BV/TV increased generally with time and there were significant differences (p=0.003) between each time group. While Tb.Sp decreased with time and changed significantly during the eighth week compared with that during the first week (p=0.021), differences in SMI, Tb.Th and Conn.D did not differ significantly according to time of implant. The significant increase in the Tb.N and BV/TV during the eighth week after insertion of implants indicates that the formation of new bone before the eighth week is the key to osseointegration.

Effect of sinus membrane perforation on the survival of implants placed in combination with osteotome sinus floor elevation.

This study was conducted to evaluate implant survival with regard to effects of sinus membrane perforation that occurred during osteotome sinus floor elevation (OSFE). The study group consisted of 42 patients with edentulous posterior maxilla. Implants placement combined with OSFE without a grafting material was performed. All patients underwent a radiographic examination before surgery, to reveal the periimplant bone formation immediately after implant placement and 6 to 33 months later. Sinus membrane perforations were detected in 6 patients, and 6 implants were inserted in 6 sinus sites. No infection occurred in all sites, and all implants succeeded in the observation follow-up period. There was a 100% survival rate of implant in perforated sinuses, the same as in intact sinuses. Within the limits of this study, we can conclude that perforation of the sinus membrane does not compromise the short-term survival of dental implants placed in combination with OSFE.

[Clinical application of a self-developed bone collector in dental implantation].

OBJECTIVE: To introduce a self-developed bone collector designed by the authors and evaluate its effect in clinical application. METHODS: A self-developed bone collector was used in 38 patients who underwent the dental implant operation from May 2008 to October 2009. During the operation the bone particles were harvested, which was used for the reconstruction of the bone defects around the implant simultaneously. The defects were fenestrate in 29 regions and triangle in 23 regions on buccal or lingual side of the dental implants. RESULTS: All cases had no surgical wound infection and dehiscence 7 - 10 days after operation. Three to six months after implantation, the X-ray showed that all the dental implants had perfect osseointergration and the alveolar bone were successfully augmented. CONCLUSIONS: Bone debris harvested by self-developed bone collector could repair small peri-implant bone defects, which is simple to use in clinic.

Real time 3D simulation for nose surgery and automatic individual prosthesis design.

This paper presents an intuitive nose surgery planning and simulation system, using 3D laser scan image and lateral X-ray image, to provide high quality prediction of the postoperative appearance, and design the patient specific prosthesis model automatically. After initial registration, the internal surface of soft tissue at the nose region was generated by the statistical data for soft tissue thickness adapted by the individual thickness information from the X-ray image. Then, the sketch contour of the 3D scan data on the lateral X-ray image was modified manually or adjusted automatically according to some aesthetic statistical data, to drive the simulation in real time by the state-of-the-art Laplacian surface deformation method. When satisfied with the 3D postoperative appearance, the deformation was mapped to the internal surface of soft tissue, and the change before and after simulation was utilized to generate the patient specific prosthesis model automatically. The surgeons who used the system confirmed that this planning system is attractive and has potential for daily clinical practice.

[Three dimension finite element analysis of anisotropic mandible with dental implants effect on implant-bone interface].

OBJECTIVE: To establish anisotropic mandible model with dental implants and to investigate the effect of anisotropy material on stress and strain distribution of implant-bone interface. METHODS: Three-dimensional finite element models of whole mandible with anisotropic and equivalent isotropic material were created by CT scanning and universal surgical integration system (USIS) software developed by the authors. Two ITI threaded implants were implanted in the posterior teeth area. The values of principal stress and principal strain on the bone around dental implants were calculated in two different finite element models with buccolingual load. RESULTS: In the anisotropic mandible model, nearly all values of the principal stress and principal strain on cortical and cancellous bone increased compared with the equivalent isotropy model, 2.1%-74.1% for principal stress and 4.7%-57.3% for principal strain, but 10. 3%-71.4% for principal stress and 19.5%-63.4% for principal strain on cancellous bone. CONCLUSIONS: In the three-dimensional finite element analysis, anisotropic mandible model with dental implants has an apparent effect on the stress and strains of the implant-bone interface. Anisotropic mechanical properties of mandible should be emphasized in biomechanical study.

Implant-bone interface stress distribution in immediately loaded implants of different diameters: a three-dimensional finite element analysis.

PURPOSE: To establish a 3D finite element model of a mandible with dental implants for immediate loading and to analyze stress distribution in bone around implants of different diameters. MATERIALS AND METHODS: Three mandible models, embedded with thread implants (ITI, Straumann, Switzerland) with diameters of 3.3, 4.1, and 4.8 mm, respectively, were developed using CT scanning and self-developed Universal Surgical Integration System software. The von Mises stress and strain of the implant-bone interface were calculated with the ANSYS software when implants were loaded with 150 N vertical or buccolingual forces. RESULTS: When the implants were loaded with vertical force, the von Mises stress concentrated on the mesial and distal surfaces of cortical bone around the neck of implants, with peak values of 25.0, 17.6 and 11.6 MPa for 3.3, 4.1, and 4.8 mm diameters, respectively, while the maximum strains (5854, 4903, 4344 muepsilon) were located on the buccal cancellous bone around the implant bottom and threads of implants. The stress and strain were significantly lower (p < 0.05) with the increased diameter of implant. When the implants were loaded with buccolingual force, the peak von Mises stress values occurred on the buccal surface of cortical bone around the implant neck, with values of 131.1, 78.7, and 68.1 MPa for 3.3, 4.1, and 4.8 mm diameters, respectively, while the maximum strains occurred on the buccal surface of cancellous bone adjacent to the implant neck, with peak values of 14,218, 12,706, and 11,504 microm, respectively. The stress of the 4.1-mm diameter implants was significantly lower (p < 0.05) than those of 3.3-mm diameter implants, but not statistically different from that of the 4.8 mm implant. CONCLUSIONS: With an increase of implant diameter, stress and strain on the implant-bone interfaces significantly decreased, especially when the diameter increased from 3.3 to 4.1 mm. It appears that dental implants of 10 mm in length for immediate loading should be at least 4.1 mm in diameter, and uniaxial loading to dental implants should be avoided or minimized.