Morphometric study of foramina transversaria in Jordanian population using cross-sectional computed tomography

Anatomical Science International - Foramina transversaria are bilateral landmarks of human cervical vertebrae. Morphometric analysis of foramina transversaria is valuable in both clinical and...     

Rebamipide potentially mitigates methotrexate-induced nephrotoxicity via inhibition of oxidative stress and inflammation: A molecular and histochemical study

Methotrexate (MTX) is a widely used chemotherapeutic agent; nevertheless, the nephrotoxicity associated with its use has limited its clinical use. Rebamipide (REB) is a gastro-protective agent with diverse promising biological activities. Here, we investigated the renoprotective effects of REB against MTX-induced nephrotoxicity in rats. Male Wistar rats were allocated into four groups: the normal control group, the REB group (100 mg kg⁻¹ day⁻¹, PO, for 12 days), the MTX group (which received a single injection of 20 mg/kg, ip), and the REB + MTX group (which received 100 mg kg⁻¹ day⁻¹ REB for 7 days before and 5 days after being injected with 20 mg/kg MTX). Interestingly, MTX triggered kidney injury, characterized by renal dysfunction along with histopathological alterations. Moreover, increased reactive oxygen species level and inflammatory response were detected in the kidney of MTX-treated rats. However, REB prevented MTX-induced oxidative kidney injury and boosted an antioxidant balance. Mechanistically, REB markedly activated the NRF-2 protein and upregulated the expression of both SIRT-1 and FOXO-3 genes. Additionally, REB administration strongly inhibited the inflammatory response by downregulating both NF-κB-p65 and TLR-4. Finally, the coadministration of REB and MTX activated the mTOR/PI3K/AKT signaling pathway. Simultaneously, REB treatment attenuated the reduction in glomerular size, the widening of the capsular spaces, and the tubular cell damage due to MTX administration. Taken together, these results indicate the potential of REB as adjuvant therapy to prevent nephrotoxicity in patients receiving MTX treatment.     

Comparison of conventional,photogrammetry, and intraoral scanning accuracy of complete-arch implant impression procedures evaluated with a coordinate measuring machine

Statement of problemConventional implant impressions by using elastomeric impression material have been reported as a more reliable technique for a complete-arch implant record compared with intraoral scanner procedures. Photogrammetry technology may provide a reliable alternative to digital scanning or a conventional impression; however, its accuracy remains unclear.PurposeThe purpose of this in vitro study was to measure and compare the implant abutment replica positions of the definitive cast with the implant abutment replica positions obtained by the conventional technique, photogrammetry, and 2 intraoral scanners.Material and methodsAn edentulous maxillary cast with 6 implant abutment replicas (RC analog for screw-retained abutment straight) was prepared. Three impression techniques were performed: the conventional impression technique (CNV group) by using a custom tray elastomeric impression procedure after splinting the impression copings at room temperature (23°C), photogrammetry (PG group) technology (Icam4D), digital scans by using 2 different IOSs following the manufacturer′s recommended scanning protocol, namely IOS-1 (iTero Element) and IOS-2 (TRIOS 3) groups (n=10). A coordinate measuring machine (CMM Contura G2 10/16/06 RDS) was used to measure the implant abutment replica positions of the definitive casts and to compare the linear discrepancies at the x-, y-, and z-axes and the angular distortion of each implant abutment replica position by using a computer aided-design software program (Geomagic) and the best fit technique. The 3D linear gap discrepancy was calculated. Measurements were repeated 3 times. The Shapiro-Wilk test revealed that the data were not normally distributed; therefore, the Kruskal-Wallis test was used to analyze the data, followed by pairwise Mann-Whitney U tests (α=.05).ResultsSignificant y-axis linear and XY and YZ angular discrepancies were found among the CNV, PG, IOS-1, and IOS-2 groups (P<.05). The PG group obtained a significantly higher distortion on the y-axis and 3D gap compared with all the remaining groups (P=.004). The 3D discrepancy of the CNV group was 11.7 μm, of the IOS-1 group was 18.4 μm, of the IOS-2 was 21.1 μm, and of the PG group was 77.6 μm. In all groups, the interquartile range was higher than the median errors from the discrepancies measured from the definitive cast, indicating that the relative precision was low.ConclusionsThe conventional technique reported the lowest 3D discrepancy for the implant abutment position translation capabilities of all the implant techniques evaluated. The intraoral scanners tested provided no significant differences in linear distortion compared with the conventional method. However, the photogrammetry system tested provided the least accurate values, with the highest 3D discrepancy for the implant abutment positions among all the groups.     

Effect of shoulder girdle strengthening on trunk alignment in patients with stroke

[Purpose] This study investigated the effect of shoulder girdle strengthening, particularly the scapular muscles, on poststroke trunk alignment. [Subjects and Methods] The study involved 30 patients with residual hemiparesis following cerebrovascular stroke. Patient assessment included measuring shoulder muscle peak torque, scapular muscles peak force, spinal lateral deviation angle, and motor functional performance. Patients were randomly allocated either to the control group or the study group and received an 18-session strengthening program including active resisted exercises for shoulder abductors and external rotators in addition to trunk control exercises. The study group received additional strengthening exercises for the scapular muscles. [Results] The two groups showed significant improvement in strength of all shoulder and scapular muscles, with higher improvement in the study group. Similarly, the lateral spinal deviation angles significantly improved in both groups, with significantly higher improvement in the study group. Transfer activity, sitting balance, upper limb functions, and hand movements significantly improved in the two groups, with higher improvement in the latter two functions in the study group. [Conclusion] Strengthening of shoulder girdle muscles, particularly scapular muscles, can significantly contribute to improving the postural alignment of the trunk in patients with poststroke hemiparesis.Key words: Stroke, Scapular muscles strengthening, Lateral trunk alignment     

A finite element study on stress distribution of two different attachment designs under implant supported overdenture

Objective

This study aimed to evaluate stress patterns generated within implant-supported mandibular overdentures retained by two different attachment types: ball and socket and locator attachments.

Materials and methods

Commercial CAD/CAM and finite element analysis software packages were utilized to construct two 3D finite element models for the two attachment types. Unilateral masticatory compressive loads of 50, 100, and 150 N were applied vertically to the overdentures, parallel to the longitudinal axes of the implants. Loads were directed toward the central fossa in the molar region of each overdenture, that linear static analysis was carried out to find the generated stresses and deformation on each part of the studied model.

Results

According to FEA results the ball attachment neck is highly stressed in comparison to the locator one. On the other hand mucosa and cortical bone received less stresses under ball and socket attachment.

Conclusions

Locator and ball and socket attachments induce equivalent stresses on bone surrounding implants. Locator attachment performance was superior to that of the ball and socket attachment in the implants, nylon caps, and overdenture. Locator attachments are highly recommended and can increase the interval between successive maintenance sessions.