Microplate Versus Combined Microplate-Miniplate in Fixation of Zygomaticomaxillary Complex Fractures: An In-Silico Analysis of Biomechanical Parameters.

Introduction: To compare the biomechanical parameters of microplates and the combined miniplate-microplate for fixing zygomaticomaxillary complex (ZMC) fractures using nonlinear finite element analysis (FEA). Material and Methods: Two samples of ZMC fracture models were prepared. In sample 1 (S1), the fractures were stabilized with microplates, and in sample 2 (S2), with miniplates plus microplates. FEA software was used to measure the displacement, Von Mises stress distribution (VMSD), and maximum principal stress distribution (MPSD). Results: The displacement was 6.7 µm in the L-shaped plate of both samples, 4.4 µm in the S1 lateral-edge plate, 4.8 µm in the S2 lateral-edge plate, 5.8 µm in the S1 bottom-edge plate, and 5.6 µm in the S2 bottom-edge plate. The VMSD was 41.1 MPa in the S1 lateral-edge plate, 24.3 MPa in the S2 lateral-edge plate, 7.6 MPa in the S1 Lshaped plate, 9.6 MPa in S2 L-shaped plate, 28.5 MPa in the S1 bottom-edge plate, and 11.8 MPa in the S2 bottom-edge plate. The MPSD was 46.2 MPa in the S1 lateral-edge plate, 26.4 MPa in the S2 lateral-edge plate, 3.6 MPa in S1 L-shaped plate, 4.2 MPa in S2 L-shaped plate, 30.9 MPa in S1 bottom-edge plate, and 14.1 MPa in the S2 bottom-edge plate. Conclusion: The L-shaped and lateral-edge plates in both samples had the highest and lowest amount of displacement, respectively. The lateral-edge plates in both samples had the highest VMSD and MPSD, which was higher in S1 than S2. The L-shaped plate had the lowest VMSD and MPSD in both samples.

Evaluation of changes in exhausted T lymphocytes and miRNAs expression in the different trimesters of pregnancy in pregnant women.

BACKGROUND: Throughout the three trimesters of a typical pregnancy, we looked at changes in the expression of miRNAs and exhausted T lymphocytes for this study. METHODS AND RESULTS: Fifty healthy subjects were included in this study. The frequency of exhausted T lymphocytes was measured in isolated PBMCs using flow cytometry. PD-1, TIM-3, and related miRNAs gene expression were assessed using qRT-PCR. The analyses revealed a significant decline in PD-1 and Tim-3 expression in PBMCs from RPL women (p = 0.0003 and p = 0.001, respectively). In addition, PD-1 and TIM-3 expression increased significantly in the 2nd trimester compared with the 1st trimester of healthy pregnant women (p < 0.0001 and p = 0.0002, respectively). PD-1 and TIM-3 expression was down-regulated in the 3rd trimester compared with the 1st and 2nd trimesters. In the present study, we demonstrated that TIM-3+/CD4+, TIM-3+/CD8+, PD-1+/CD4+, and PD-1+/CD8 + exhausted T lymphocytes increased in the circulation of women in the 2nd trimester compared to the 1st and 3rd trimester. In the 3rd trimester, the expression of miR-16-5p increased significantly (p < 0.0001). miR-125a-3p expression was down and upregulated in 2nd (p < 0.0001) and 3rd (p = 0.0007) trimesters compared to 1st trimester, respectively. This study showed a significant elevation of miR-15a-5p in 3rd trimester compared to 1st trimester of pregnant women (p = 0.0002). CONCLUSIONS: Expression pattern of PD-1 and TIM3 in exhausted T lymphocytes is different not only between normal pregnant and RPL women but also in different trimesters of pregnancy. So, our results showed the role of these markers in the modulation lymphocytes activity in different stages of pregnancy.

The effect of local injection of bupivacaine with and without fentanyl at the operative site in mandibular open reduction on acute pain intensity and opioid requirement: a randomized clinical trial.

PURPOSE: The aim of this study is to investigate the effects of bupivacaine local injection with and without fentanyl at the operative site in mandibular open reduction surgeries on the severity of acute pain and the need for opioids. METHODS: This randomized clinical trial, age-sex-matched double-blind study included 44 patients with isolated mandibular fractures who would be candidates for open reduction. They were divided into two groups (intervention using fentanyl and control not using fentanyl). In both groups, the amount of opioid used, hemodynamic indices, oxygen saturation, and pain intensity were collected based on the Visual Analogue Scale (VAS) every 4 h for 24 h. RESULTS: As for basic and demographic variables such as gender, age, ASA class, and duration of surgery (P > 0.05), there was neither a significant difference between the two groups nor was there any difference in nausea and vomiting and subsequent anti-nausea medication (P > 0.05). The need for a post-operative opioid in the bupivacaine + fentanyl group (13.6%) was significantly less than in those who received only bupivacaine (45.5%) (P < 0.05). Changes in pain scores over time were significantly different in the two groups, and bupivacaine + fentanyl reduced pain more than bupivacaine (P < 0.05). However, over time, there was no significant difference between the two groups in terms of changes in oxygen saturation, heart rate, systolic blood pressure, and diastolic blood pressure (P > 0.05). CONCLUSION: The addition of fentanyl to bupivacaine for supraperiosteal injection in the open reduction surgery site reduces post-operative pain in the first 24 h and reduces the need for opioids without causing complications such as nausea and vomiting.

T Lymphocyte Characteristic Changes Under Serum Cytokine Deviations and Prognostic Factors of COVID-19 in Pregnant Women.

Physiological changes during pregnancy make the individuals more susceptible to severe respiratory diseases. Hence, pregnant women with coronavirus disease 2019 (COVID-19) are likely at a higher risk. We investigated the effects of COVID-19 on T cell response and serum cytokine profile in pregnant patients. Peripheral blood mononuclear cells (PBMCs) of women with COVID-19 were collected during the first trimester of pregnancy, and the percentage of total lymphocytes, as well as CD4 + and CD8 + T cells, was assessed using flow cytometry. The expression of the programmed death-1 (PD-1) marker for exhausted T cells was evaluated. Additionally, the serum samples were provided to evaluate the levels of antiviral and proinflammatory cytokines, as well as laboratory serological tests. Pregnant women with COVID-19 presented lymphopenia with diminished CD4 + and CD8 + T cells. Besides, high expression levels of the PD-1 gene and protein were observed on PBMCs and T cells, respectively, when compared with normal pregnant individuals. Moreover, serum levels of TNF-α, IL-6, IL-1ß, and IL-2 receptor were notably enhanced, while IFN-I α/ß values were significantly decreased in the patients when compared with controls. Furthermore, hyperlipidemia, hyperglycemia, and hypertension were directly correlated with the disease although serum albumin and vitamin D3 levels adversely affected the viral infection. Our study showed extreme lymphopenia and poor T cell response while elevated values of serum inflammatory cytokines in infected pregnant women. Moreover, a hypertension background or metabolic changes, including hyperlipidemia, hyperglycemia, and vitamin D3 or albumin deficiency, might be promising prognostic factors in pregnant women with COVID-19.

Anterior Palatal Fistula Formation after Le Fort I Osteotomy in Conventional Orthognathic Surgery.

The prevalence rate of maxillary ischemic complications following Le Fort I osteotomy was estimated to be about 1%. Understanding the local and systemic factors affecting maxillary perfusion before, during, and after the surgery can prevent the development of these complications. The present study investigated a case of anterior palatal fistula following the classic Le Fort I osteotomy.

Comparison of shear bond strengths with different bevel preparations for the reattachment of fractured fragments of maxillary central incisors.

BACKGROUND/AIMS: Fractures of anterior teeth are a highly prevalent form of dental trauma. Among the various treatment options, reattachment of the fractured part to the remaining tooth has a lot of advantages. The aim of this study was to compare different bevel preparation techniques when reattaching fractured fragments to maxillary central incisors. METHODS: This study was performed on 52 maxillary central incisors that were randomly divided into 3 experimental groups and 1 control group. In the control group, the repair was done by attaching the fractured fragment using bonding and composite resin without any bevel preparation. In the second and third groups, the bevel preparation was done to a depth of 0.5 mm before attachment of the fragment on the palatal side of the fracture and on the labial and palatal sides, respectively. In the fourth group, after tooth preparation, a 0.5 mm composite veneer was placed on the labial surface. The amount of force needed to refracture the tooth was measured with a universal testing machine, and shear bond strength was calculated in MPa. RESULTS: The mean and standard deviation (mean ± SD) of shear bond strengths in the control group were 81.48 ± 8.18 MPa. In the palatal bevel group, they were 97.74 ± 11.41 MPa; in the labial and palatal bevel group, 131.56 ± 9.25 MPa; and in the composite veneer group, 104.36 ± 5.50 MPa. Significant differences were observed between the groups, but there was no significant difference between the palatal bevel and composite veneer groups. CONCLUSIONS: Reattachment of the fractured fragments by all three methods increased the shear bond strength. The highest shear bond strength was obtained when both labial and palatal bevels were used.

Prospects for the application of mesenchymal stem cells in Alzheimer's disease treatment.

Alzheimer's disease (AD) as a dementia and neurodegenerative disease, is mostly prevalent among people more than 65 years. AD is mostly manifested in the form of degraded mental function, such as losing memory and impaired cognitive function. Due to inefficiency of traditional pharmacological therapeutic approaches with no long-term cure, cell therapy can be considered as a capable approach in AD management. Therapies based on mesenchymal stem cells (MSCs) have provided hopeful results in experimental models regarding several disorders. MSCs enhance the levels of functional recoveries in pathologic experimental models of central nervous system (CNS) and are being investigated in clinical trials in neurological disorders. However, there is limited knowledge on the protective capabilities of MSCs in AD management. Almost, several experiments have suggested positive effects of MSCs and helped to better understand of AD-related dementia mechanism. MSCs have the potential to be used in AD treatment through amyloid-ß peptide (AB), Tau protein and cholinergic system. This review aimed to clarify the promising perspective of MSCs in the context of AD.

Anesthetic efficacy of articaine/epinephrine plus mannitol in comparison with articaine/epinephrine anesthesia for inferior alveolar nerve block in patients with symptomatic irreversible pulpitis: A randomized controlled clinical trial.

Background. It is difficult to achieve successful pulpal anesthesia in mandibular posterior teeth with symptomatic irreversible pulpitis. The present study aimed to compare the effect of articaine/epinephrine anesthesia with articaine/epinephrine at a combination of 0.5 mol/mL of mannitol for the inferior alveolar nerve block (IANB) in patients presenting with symptomatic irreversible pulpitis in the mandibular first molar tooth. Methods. One hundred patients with symptomatic irreversible pulpitis in the mandibular first molar tooth were selected and randomly divided into two groups based on the injection method. The first group underwent an IANB technique with 1.8 mL of articaine, whereas the second group received 2.9 mL of a formulation, consisting of 1.8 mL of articaine plus 1.1 mL of 0.5 mol/L of mannitol. Fifteen minutes after injections and anesthesia of the lip, the access cavity was prepared. According to the visual analog scale (VAS) criteria, no pain or mild pain for caries removal, pulp exposure and canal instrumentation were regarded as success. Chi-squared test was used for the analysis of data. The level of significance was set at 0.05. Results. The success rate in the group with articaine/epinephrine anesthesia plus mannitol was higher than that in the group with articaine/epinephrine anesthesia, with no significant difference between the two groups (P>0.05). Conclusion. It was concluded, under the limitations of this study, that adding mannitol to articaine/epinephrine anesthesia did not increase the success of IANB in mandibular posterior teeth with symptomatic irreversible pulpitis.

Comparison of edema and ecchymosis in rhinoplasty candidates after lateral nasal osteotomy using piezosurgery and external osteotomy.

Rhinoplasty is done with external and endonasal methods. One of the main stages of rhinoplasty in both external and endonasal methods is the lateral nasal osteotomy. Lateral nasal osteotomy is the main cause of edema and ecchymosis after rhinoplasty, which is annoying and unpleasant for patients. Piezosurgery is a new method that uses electronic-ultrasonic waves to perform nasal osteotomies. The aim of this study was to compare of edema and ecchymosis after lateral nasal osteotomy using piezosurgery with external osteotomy in rhinoplasty candidates. In this clinical trial, 66 experimental patients for rhinoplasty surgery were selected from Imam Reza hospital in Tabriz, Iran. After examination, the patients were randomly divided into two groups. One group of patients had lateral nasal osteotomy by using the piezosurgery technique, and the other group had a lateral osteotomy with the conventional method of external subcutaneous. On the third and 7 days after the operation, the level of edema and ecchymosis in the patients were examined as per the Gökalan questionnaire (adopted by Yucel) by two persons who were not aware of the goals of the study, and then, they evaluated and scored the questionnaire. The obtained data were analyzed by the SPSS 19 software. The highest level of edema and ecchymosis was observed 3 days after surgery in both groups. Meanwhile, the findings revealed a significant difference between the two groups in the amount of edema and ecchymosis on day 3 after surgery. Furthermore on day 7, the amount of edema and ecchymosis compared to that of the 3rd day was statistically significant for both groups. In general, in all studied groups, edema, and ecchymosis decreased in 7 days compared to 3 days and also piezosurgery is more promising and effective than osteotomy.

Determination of the diagnostic value of the Modified Mallampati Score, Upper Lip Bite Test and Facial Angle in predicting difficult intubation: A prospective descriptive study.

BACKGROUND: Difficult intubation is a significant cause of mortality and morbidity related to anesthesia. We decided to evaluate the value of Modified Mallampati Score, Upper Lip Bite Test and Facial Angle in the prediction of difficult intubation. METHODS: In a prospective descriptive study, data from 132 patients who were candidates for elective maxillofacial surgeries under general anesthesia were gathered. Facial Angles were measured by a maxillofacial surgeon according to cephalometry. The Modified Mallampati Score and Upper Lip Bite Test were first measured by an anesthesiologist and then another anesthesiologist was assigned to record the Cormack and Lehane score during the intubation. Grades 3 and 4 were considered as difficult intubation. Sensitivity, specificity, positive predictive value, negative predictive value and Youden index were calculated for all tests. RESULTS: Difficult intubation was reported in 12% of the patients. Facial Angle≤82.5° can predict difficult intubation with 87.5% sensitivity and 88.8% specificity. Among the three tests, a high Modified Mallampati Score had the highest specificity (94.5%) and a high Modified Mallampati Score and Facial Angle (FA≤82.5°) had the highest sensitivity (87.5%). The highest NPV, sensitivity and Youden index were observed when using Facial Angle with the Modified Mallampati Score or with Upper Lip Bite Test. CONCLUSIONS: Facial Angle has a high sensitivity, NPV and Youden index for the prediction of difficult intubation, but the best result is achieved when Facial Angle is used in combination with either the Modified Mallampati Score or Upper Lip Bit Test.

Effect of Preoperative Oral Amantadine on Acute and Chronic Postoperative Pain After Mandibular Fracture Surgery.

BACKGROUND: Postoperative pain from open reduction and internal fixation of mandibular fracture is a serious issue. Amantadine is an N-methyl-D-aspartic acid or N-methyl-D-aspartate (NMDA) receptor antagonist that can be effective against postoperative pain. OBJECTIVES: The present study examined the efficacy of amantadine in alleviating the postoperative pain of mandibular fracture surgery. PATIENTS AND METHODS: In this double-blind study, 60 patients (ASA physical status I-II) were randomly divided into two groups. The mean ages of the participants were 31.2 ± 13.1 years and 32.3 ± 18.1 years, respectively. The male/female ratios were 24/6 and 26/4, respectively, in the case and control groups. Randomization was based on a single sequence of random assignments using computer-generated random numbers. Group I was given oral amantadine 100 mg 1 hour before surgery, and group II received a placebo at the identical time. Through PCA pumps, patients received a bolus dose of morphine at 0.02 mg/kg body weight, to a maximum of 1.5 mg. PCA pumps were set at 6 minutes lockout intervals and a maximum dose of 0.15 mg/kg/h, to a maximum of 10 mg/h. Pain was assessed using a visual analog scale (VAS) at 0, 2, 4, 6, 12, and 24 hours and 1, 2, 3, 4, 5, and 6 months after surgery. The amounts of analgesic consumed were recorded for the first 24 hours, and for 6 months after surgery. RESULTS: There were no significant differences between the two groups with respect to age, gender, nausea and vomiting, sleep quality, blood pressure, and heart rate. No significant differences were observed between the two groups in pain scores (P = 0.39) and analgesic consumption (P = 0.78). CONCLUSIONS: The results suggest that a single dose of preoperative oral amantadine did not reduce acute or chronic postoperative pain, nor analgesic consumption.