XT-5

Introduction: Tourniquet application is an urgent life-saving procedure. Previous studies demonstrated several drawbacks in tourniquet design and application methods that limit their efficacy; among them, loose application of the device before windlass twisting is a main pitfall. A new generation of modern combat tourniquets was developed to overcome these pitfalls. The objective of this study was to assess the effectiveness of three new tourniquet designs: the CAT Generation 7 (CAT7), the SAM Extremity Tourniquet (SAM-XT), and the SOF Tactical Tourniquet Wide (SOFTT-W) as well as its correlation to the degree of slack. Materials and methods: The three tourniquet models were applied in a randomized sequence on a HapMed leg tourniquet trainer, simulating an above-the-knee traumatic amputation by 60 military medicine track cadets. Applied pressure, hemorrhage control status, time until the bleeding stopped, estimated blood volume loss, and slack were measured. Results: The mean (±SD) pressure applied using the SAM-XT (186 mmHg ±63) or the CAT7 (175 mmHg ±79) was significantly higher compared to the pressure applied by the SOFTT-W (104 mmHg ±101, P < 0.017), with no significant difference between the first two (P > 0.05). Hemorrhage control rate was similar (P > 0.05) with SAM-XT (73.3%) and CAT7 (67.7%), and both were significantly better than the SOFTT-W (35%, P < 0.017). Slack was similar between CAT7 and SAM-XT (5.2 mm ± 3.4 vs. 5 mm ± 3.5, P > 0.05), yet significantly lower compared to the SOFTT-W (9 mm ± 5, P < 0.017). A strong negative correlation was found between slack and hemorrhage control rate (3.2 mm ± 1.5 mm in success vs. 10.5 mm ± 3.4 mm in failure, P < 0.001) and applied pressure (Pearson's correlation coefficient of -0.83, P < 0.001). Conclusions: Both SAM-XT and CAT7 demonstrated a better pressure profile and hemorrhage control rate compared to SOFTT-W, with no significant difference between the two. The better outcome measures were strongly correlated to less slack.

Statement of problem: The polymerization of computer-aided design and computer-aided manufacturing (CAD-CAM) composite resins during their manufacture enhances their physical properties and biocompatibility but might compromise their reparability. Purpose: The purpose of this in vitro study was to determine the microtensile bond strength and nanoleakage (NL) of aged LAVA Ultimate (LU) CAD-CAM composite resin after different repair protocols. Material and methods: Fifty-eight LU miniblocks were prepared, thermocycled (10000 cycles, 5°C to 55°C), and assigned to 10 surface pretreatment and bonding protocols: (1) tribochemical silica coating (CoJet, CoJet Sand; 3M ESPE)+Scotchbond Universal Adhesive (SBU; 3M ESPE); (2) CoJet+silane (SI, ESPE Sil; 3M ESPE)+Adper Scotchbond 1 XT Adhesive (XT; 3M ESPE); (3) CoJet+10-methacryloyloxydecyl dihydrogen phosphate-based silane (MO; Monobond Plus; Ivoclar Vivadent AG)+XT; (4) CoJet+XT; (5) 30-μm alumina airborne-particle abrasion (AL)+SBU; (6) AL+SI+XT; (7) AL+MO+XT; (8) AL+XT; (9) no pretreatment+SBU; and (10) no pretreatment+XT. All blocks were repaired using the Filtek Supreme XTE (3M ESPE) composite resin. Stick-shaped specimens (0.9×0.9 mm) were obtained and submitted to microtensile bond strength (μTBS) and %NL testing after 24 hours. μTBS data were analyzed with 1-way ANOVA, followed by the Tukey post hoc test, and NL data with nonparametric Kruskal-Wallis and Dunn tests (α=.05). Results: For μTBS, CoJet, and AL pretreatments showed significantly higher mean μTBS, especially when used together with SBU. No pretreatment+XT yielded the lowest mean μTBS. For NL, marginal sealing improved significantly after the use of SBU regardless of the surface treatment. This improvement was only statistically different after tribochemical silica coating. Conclusions: Airborne-particle abrasion with alumina particles, silica coated or not, together with the application of SBU resulted in the highest mean μTBS. The lowest %NL was recorded when aged LU blocks were repaired using SBU.

The present study investigates the results of Cuppers' 'Fadenoperation' in patients with non-accommodative convergence excess esotropia. Particular attention is given to postoperative eye alignment at distance fixation. Group 1 (n=96) included patients with a 'normal' convergence excess. The manifest near angles (mean ET 16.73 degrees +/- 6.33 degrees, range 4 degrees -33 degrees ) were roughly twice the size of the distance angles (mean ET 6.50 degrees +/- 3.62 degrees, range 0 degrees -14 degrees ). These patients were treated with a bilateral fadenoperation of the medial recti without additional eye muscle surgery. Three months after surgery, the mean postoperative angles were XT 0.5 degrees +/- 3.3 degrees (range XT 11 degrees -ET 5 degrees ) for distance fixation, and ET 2.7 degrees +/- 3.6 degrees (range XT 5 degrees -ET 14 degrees ) for near fixation, respectively. Postoperative convergent angles at near fixation >ET 10 degrees were present in two patients (1.9%). Group 2 (n=21) included patients with a mean preoperative distance angle of ET 9.2 degrees +/- 3.7 degrees (range 6 degrees -16 degrees ) and a mean preoperative near angle of ET 23.4 degrees +/- 3.1 degrees (range 16 degrees -31 degrees ). These patients were operated on with a bilateral fadenoperation of the medial recti and a simultaneous recession of one or both medial rectus muscles. Mean postoperative angles were XT 0.5 degrees +/- 4.6 degrees (range XT 12 degrees -ET 7 degrees ) for distance fixation and ET 1.4 degrees +/- 4.5 degrees (range XT 8 degrees -ET 13 degrees ) for near fixation, respectively. In this group, 2 patients (10.6%) had a postoperative exotropia >XT 5 degrees at distance fixation, and two patients had residual esotropia>ET 10 degrees at near fixation. Group 3 (n=17) included patients with a pronounced non-accommodative convergence excess. Near angle values (mean of 17.8 degrees +/- 5.3 degrees, range ET 7 degrees -26 degrees ) were several times higher than the distance angle values (mean ET 1.9 degrees +/- 4.2 degrees, range XT 3 degrees -ET 6 degrees ). These patients were treated with a bilateral fadenoperation of the medial recti and a simultaneous resection of one or both medial rectus muscles. Mean postoperative angles were ET 0.2 degrees +/- 4.7 degrees (range XT 8 degrees -ET 6 degrees ) for distance fixation and 5.3 degrees +/- 6.1 degrees (range XT 3 degrees -ET 12 degrees ) for near fixation, respectively. One patient had a postoperative distance angle >XT 5 degrees, whereas two patients displayed postoperative convergent angles >ET 5 degrees at near fixation.