Influence of augmented reality technique on the accuracy of autotransplanted teeth in surgically created sockets.

BACKGROUND: The objective of the present study was to evaluate the reliability of an augmented reality drilling approach and a freehand drilling technique for the autotransplantation of single-rooted teeth. MATERIALS AND METHODS: Forty samples were assigned to the following surgical techniques for drilling guidance of the artificial sockets: A. augmented reality technique (AR) (n = 20) and B. conventional free-hand technique (FT) (n = 20). Then, two models with 10 teeth each were submitted to a preoperative cone-beam computed tomography (CBCT) scan and a digital impression by a 3D intraoral scan. Afterwards, the autotrasplanted teeth were planned in a 3D dental implant planning software and transferred to the augmented reality device. Then, a postoperative CBCT scan was performed. Data sets from postoperative CBCT scans were aligned to the planning in the 3D implant planning software to analize the coronal, apical and angular deviations. Student's t-test and Mann-Whitney non-parametric statistical analysis were used to analyze the results. RESULTS: No statistically significant differences were shown at coronal (p = 0.123) and angular (p = 0.340) level; however, apical deviations between AR and FT study groups (p = 0.008) were statistically significant different. CONCLUSION: The augmented reality appliance provides higher accuracy in the positioning of single-root autotransplanted teeth compared to the conventional free-hand technique.

Influence of the Geometrical Cross-Section Design on the Dynamic Cyclic Fatigue Resistance of NiTi Endodontic Rotary Files-An In Vitro Study.

The aim of this study was to analyze and compare the influence of the geometrical cross-section design on the dynamic cyclic fatigue resistance of NiTi endodontic rotary files. MATERIALS AND METHODS: Forty sterile endodontic rotary files were selected and distributed into the following study groups: A: 25.06 double S-shaped cross-section NiTi alloy endodontic rotary files (Mtwo) (n = 10); B: 20.04 rectangular cross-section NiTi alloy endodontic rotary files (T Pro E1) (n = 10); C: 25.04 convex triangular cross-section NiTi alloy endodontic rotary files (T Pro E2) (n = 10); and D: 25.06 triangular cross-section NiTi alloy endodontic rotary files (T Pro E4) (n = 10). A cyclic fatigue device was used to conduct the static cyclic fatigue tests with stainless steel artificial root canal systems with 200 µm and 250 µm apical diameter, 60° curvature angle, 3 mm radius of curvature, 20 mm length, and 4% and 8% taper. The results were analyzed using the ANOVA test and Weibull statistical analysis. RESULTS: All the pairwise comparisons presented statistically significant differences between the time to failure and number of cycles to failure for the cross-section design study groups (p < 0.001). CONCLUSIONS: the double S-shaped cross-section of Mtwo NiTi endodontic files shows higher cyclic fatigue resistance than the rectangular cross-section of T Pro E1 NiTi endodontic files, the convex triangular cross-section of T Pro E2 NiTi endodontic files, and the triangular cross-section of T Pro E4 NiTi endodontic files.

Antioxidant, Anti-inflammatory and Neuroprotective Profiles of Novel 1,4-Dihydropyridine Derivatives for the Treatment of Alzheimer's Disease.

Alzheimer's disease is a chronic and irreversible pathological process that has become the most prevalent neurodegenerative disease. Currently, it is considered a multifactorial disease where oxidative stress and chronic neuroinflammation play a crucial role in its onset and development. Its characteristic neuronal loss has been related to the formation of neurofibrillary tangles mainly composed by hyperphosphorylated tau protein. Hyperphosphorylation of tau protein is related to the over-activity of GSK-3ß, a kinase that participates in several pathological mechanisms including neuroinflammation. Neuronal loss is also related to cytosolic Ca2+ homeostasis dysregulation that triggers apoptosis and free radicals production, contributing to oxidative damage and, finally, neuronal death. Under these premises, we have obtained a new family of 4,7-dihydro-2H-pyrazolo[3-b]pyridines as multitarget directed ligands showing potent antioxidant properties and able to scavenge both oxygen and nitrogen radical species, and also, with anti-inflammatory properties. Further characterization has demonstrated their capacity to inhibit GSK-3ß and to block L-type voltage dependent calcium channels. Novel derivatives have also demonstrated an interesting neuroprotective profile on in vitro models of neurodegeneration. Finally, compound 4g revokes cellular death induced by tau hyperphosphorylation in hippocampal slices by blocking reactive oxygen species (ROS) production. In conclusion, the multitarget profile exhibited by these compounds is a novel therapeutic strategy of potential interest in the search of novel treatments for Alzheimer's disease.

Body Fat Percentage Rather than Body Mass Index Related to the High Occurrence of Type 2 Diabetes.

BACKGROUND: Diabetes prevalence estimation and reduction of its risk factors remain the major goals of health services. While obesity is the major risk factor for diabetes, body fat distribution may be a better predictor. AIMS: To estimate the prevalence of diabetes in an adult working population in Mexico City, and to evaluate the strength of association with different risk factors. METHODS: A cross-sectional survey was conducted in two city halls of Mexico City. Anthropometrics, blood pressure, physical activity, diet, and biochemical parameters were assessed. Diabetes was defined as a fasting plasma glucose level ≥7.0 mmol/l or referred diabetes. The bioelectrical impedance analysis of body components was performed and weight, soft lean mass, body fat percentage and abdominal fat were obtained. Prevalence with 95% confidence intervals was estimated, as well as odds ratios derived from a logistic regression model. RESULTS: The prevalence of type 2 diabetes was 11.0% (95% CI 9.6-12.4%). The proportion of individuals with diabetes who were unaware of having the disease was higher in women (42.5 vs. 36.9%), and the degree of metabolic control was better in women (39.1 vs. 25.0%). Age, blood pressure, triglycerides and the percentage of body fat, were major risk factors related to the occurrence of type 2 diabetes. No relation was observed with physical activity and diet. CONCLUSIONS: The prevalence of type 2 diabetes in Mexico continues to be high and obesity measured by body fat percentage seems to be a better predictor of its occurrence than body mass index.

Aza-CGP37157-lipoic hybrids designed as novel Nrf2-inducers and antioxidants exert neuroprotection against oxidative stress and show neuroinflammation inhibitory properties.

Two multitarget hybrids, derived from an aza-analogue of CGP37157, a mitochondrial Na+ /Ca2+ exchanger antagonist, and lipoic acid were designed in order to combine in a single molecule the antioxidant and Nrf2 induction properties of lipoic acid and the neuroprotective activity of CGP37157. The hybrid derivatives showed Nrf2 induction and radical scavenging properties, leading to a good neuroprotective profile against oxidative stress, together with an interesting antineuroinflammatory activity. The results obtained show differences in activity depending on the configuration of the chiral center of LA.

New 5-unsubstituted dihydropyridines with improved CaV1.3 selectivity as potential neuroprotective agents against ischemic injury.

C5-unsubstituted-C6-aryl-1,4-dihydropyridines were prepared by a CAN-catalyzed multicomponent reaction from chalcones, ß-dicarbonyl compounds, and ammonium acetate. These compounds were able to block Ca(2+) entry after a depolarizing stimulus and showed an improved Cav1.3/Cav1.2 selectivity in comparison with nifedipine. Furthermore, they were able to protect neuroblastoma cells against Ca(2+) overload and oxidative stress models. Their selectivity ratio makes them highly interesting for the treatment of neurological disorders where Ca(2+) dyshomeostasis and high levels of oxidative stress have been demonstrated. Furthermore, their low potency toward the cardiovascular channel subtype makes them safer by reducing their probable side effects, in comparison to classical 1,4-dihydropyridines. Some compounds afforded good protective profile in a postincubation model that simulates the real clinical situation of ictus patients, offering a therapeutic window of opportunity of great interest for patient recovery after a brain ischemic episode. Good activities were also found in acute ischemia/reperfusion models of oxygen and glucose deprivation.