The restoration of a maxillary central incisor fracture with the original crown fragment using a glass fiber‐reinforced post: a clinical report

Abstract – This report describes an esthetic, conservative, and economical alternative restoration technique for a fractured central incisor using the patient’s own tooth crown piece and a bondable reinforcement glass fiber. Although the long‐term durability of this adhesive post core restoration remains unknown, it remains successful after 1 year.     

Alteration in urinary matrix metalloproteinase-9 to tissue inhibitor of metalloproteinase-1 ratio predicts recurrence in nonmuscle-invasive bladder cancer.

PURPOSE: The purpose is to assess the prognostic significance of matrix metalloproteinase (MMP)-9 in patients with bladder cancer using a combination of ELISA (to measure MMP-9 in voided urine) and immunohistochemistry (to study MMP-9 in bladder tumors). The relationship between MMP-9 and its principal inhibitor, tissue inhibitor of metalloproteinase (TIMP)-1 (in voided urine samples) was also studied. EXPERIMENTAL DESIGN: A total of 134 patients with bladder tumors (7 cis, 76 T(a), 27 T(1), 24 T(2)-T(4); 40 G1, 43 G2, and 44 G3), 33 patients with benign urological conditions, and 36 healthy volunteers was studied. Samples from 106 patients with bladder cancer and 12 controls were stained for MMP-9. Clinical follow-up data were available on 116 patients (median: 25 months; range: 4-36 months). RESULTS: MMP-9 was present in all urine samples analyzed. There were no differences between patients with cancer and patients with benign disorders. However, patients had significantly higher urinary MMP-9 than normal volunteers (P = 0.0167). Urinary MMP-9 was associated with bladder tumors of advanced stage (P = 0.0065) and large size (P < 0.0001) but not with grade (P = 0.14), multiplicity (P = 0.31), recurrence (P = 0.55), progression (P = 0.83), or survival (P = 0.55). Low MMP-9:TIMP-1 ratios in patients with nonmuscle-invasive tumors were associated with higher recurrence rates (P = 0.0035). Sixty percent (64 of 106) of bladder tumor specimens expressed MMP-9 compared with none of 12 normal urothelial biopsies (P < 0.0001). MMP-9 staining was associated with tumor size (P = 0.014), disease progression (P = 0.005), and poor disease-specific survival (P = 0.022) but was unrelated to tumor stage (P = 0.46), grade (P = 0.26), multiplicity (P = 0.85), or recurrence rate (P = 0.62). CONCLUSIONS: High urinary MMP-9 levels are associated with large bladder tumors. A low urinary MMP-9:TIMP-1 ratio may indicate a higher risk of intraluminal nonmuscle-invasive tumor recurrence and may assist in planning follow-up surveillance protocols.     

The mutagenic,antimutagenic and antioxidant properties of Hypericum lydium

Context: There is a growing market demand for Hypericum sp., a pharmacologically active plant that has been traditionally used to treat various ailments. However, there have been limited studies on the extract or essential oil of Hypericum lydium Boiss (Hypericaceae).

Objective: This study investigates for the first time the antioxidant, mutagenic and antimutagenic activity of an ethanol extract of H. lydium.

Material and methods: Ethanol extract from aerial parts of H. lydium harvested from Turkey were tested for this mutagenic and antimutagenic activities (2.0–0.002?mg/plate) using Ames Salmonella/microsome test system. 4-Nitro-o-phenylenediamine (4-NPD) (3?μg/plate) for the Salmonella typhimurium TA98 and sodium azide (NaN₃) (8?μg/plate) for the S. typhimurium TA100 were used as positive controls. The antioxidant activity, total antioxidant activity and phenolic constituent of the extract (2.0–0.002?mg/mL) was determined by the inhibition of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), β-carotene-linoleic acid model and by means of Folin–Ciocalteu reagent, respectively.

Results: The extract showed no sign of mutagenicity at the tested concentrations (0.002–2.0?mg/mL), and showed concentration-dependent antimutagenic activity against NaN₃ and 4-NPD ranging from 26.8 to 81.5%. The extract was found to be an efficient scavenger of DPPH (IC₅₀ 0.165?±?0.23?mg/mL) and to inhibit β-carotene-linoleic acid bleaching (IC₅₀ 0.39?±?0.11?mg/mL).

Discussion and conclusion: These findings indicate ethanol extract of H. lydium to be a safe and effective agent that may be incorporated into new strategies for the prevention of cancer and mutagenesis.     

Knee Injuries in Sailboarding

Sailboarding is an exciting sport, but it does involve some risk for injury. In this study of 21 knee injuries that occurred during sailboarding over a 2-year period, 12 were isolated medial collateral ligament (MCL) sprains, 4 were meniscus tears, and 5 involved joint instability. The MCL sprains were directly related to the use of the foot straps on the sailboard. Conservative treatment was successful for the MCL sprains; the meniscus tears were treated with arthroscopic surgery. Improved foot straps designed to release the foot more readily may help reduce knee injuries.     

High‐sensitive Troponin T measurements early after heart transplantation predict short‐ and long‐term survival

Following heart transplantation, cardiac biomarkers remain elevated for several weeks eventually as a result of membrane leakage of the donor organ. We now test the predictive power of blood levels of troponin T (TNT) measured by the new hsTNT assay (Roche Diagnostics, Roche Diagnostics, Mannheim, Germany) early after heart transplantation. TNT was determined in 141 cardiac allograft recipients and 40 controls. Our findings demonstrate that patients who died within the first year after transplantation had significantly higher median hsTNT serum levels 6 weeks after transplantation (156 ng/l ± 203 vs. 29 ng/l ± 21, P = 0.0002). Using ROC analysis, a serum hsTNT concentration of 33.55 ng/l 6 weeks after transplantation was found to be the best cutoff to predict death at 1 year (HR 0.16, 95%CI:0.05–0.46, P = 0.001) with a sensitivity of 90.91% and a specificity of 70.97%. In addition, survival at 5 years (HR 0.15, 95% CI 0.06–0.35, P < 0.0001) was significantly better among patients below that cutoff value. In multivariate analysis, hsTNT serum level 6 weeks after transplantation emerged as an independent predictor for first‐year mortality (hsTNT–HR 0.90, 95% CI: 0.81–1.00, P = 0.03). Cardiac troponin T concentrations early after transplantation as measured with a highly sensitive assay represent a strong and independent risk predictor of death after heart transplantation.     

The effect of acrylamide incorporation on the thermal and physical properties of denture resins

PURPOSE

Polymethyl methacrylate (PMMA) is the most commonly used denture base material despite typically low in strength. The purpose of this study was to improve the physical properties of the PMMA based denture base resins (QC-20, Dentsply Ltd., Addlestone, UK; Stellon, AD International Ltd, Dentsply, Switzerland; Acron MC; GC Lab Technologies Inc., Alsip, Japan) by copolymerization mechanism.

MATERIALS AND METHODS

Control group specimens were prepared according to the manufacturer recommendations. In the copolymer groups; resins were prepared with 5%, 10%, 15% and 20% acrylamide (AAm) (Merck, Hohenbrunn, Germany) content according to the moleculer weight ratio, respectively. Chemical structure was characterized by a Bruker Vertex-70 Fourier transform infrared spectroscopy (FTIR) (Bruker Optics Inc., Ettlingen, Germany). Hardness was determined using an universal hardness tester (Struers Duramin, Struers A/S, Ballerup, Denmark) equipped with a Vickers diamond penetrator. The glass transition temperature (T_g) of control and copolymers were evaluated by Perkin Elmer Diamond DSC (Perkin Elmer, Massachusetts,USA). Statistical analyses were carried out using the statistical package SPSS for Windows, version 15.0 (SPSS, Chicago, IL, USA). The results were tested regarding the normality of distribution with the Shapiro Wilk test. Data were analyzed using ANOVA with post-hoc Tukey test (P<.01).

RESULTS

The copolymer synthesis was confirmed by FTIR spectroscopy. Glass transition temperature of the copolymer groups were higher than the control groups of the resins. The 10%, 15% and 20% copolymer groups of Stellon presented significantly higher than the control group in terms of hardness. 15% and 20% copolymer groups of Acron MC showed significantly higher hardness values when compared to the control group of the resin. Acrylamide addition did not affect the hardness of the QC-20 resin significantly.

CONCLUSION

Within the limitation of this study, it can be concluded that copolymerization of PMMA with AAm increased the hardness value and glass transition temperature of PMMA denture base resins.     

Peel strength of denture liner to PMMA and polyamide: laser versus air-abrasion

PURPOSE

This study investigated the effect of laser parameters and air-abrasion on the peel strength of silicon-based soft denture liner to different denture resins.

MATERIALS AND METHODS

Specimens (N=180) were prepared out of three different denture base resins (Rodex, cross-linked denture base acrylic resin; Paladent, heat-cured acrylic resin; Deflex, Polyamide resin) (75 mm × 25 mm × 3 mm). A silicon-based soft denture liner (Molloplast B) was applied to the denture resins after the following conditioning methods: a) Air-abrasion (50 µm), b) Er,Cr:YSGG laser (Waterlase MD Turbo, Biolase Technology) at 2 W-20 Hz, c) Er,Cr:YSGG laser at 2 W-30 Hz, d) Er,Cr:YSGG laser at 3 W-20 Hz, e) Er,Cr:YSGG laser at 3 W-30 Hz. Non-conditioned group acted as the control group. Peel test was performed in a universal testing machine. Failure modes were evaluated visually. Data were analyzed using two-way ANOVA and Tukey''s test (α=.05).

RESULTS

Denture liner tested showed increased peel strength after laser treatment with different parameters (3.9±0.4 - 5.58±0.6 MPa) compared to the control (3.64±0.5 - 4.58±0.5 MPa) and air-abraded groups (3.1±0.6 - 4.46±0.3 MPa), but the results were not statistically significant except for Paladent, with the pretreatment of Er,Cr:YSGG laser at 3 W-20 Hz. Polyamide resin after air-abrasion showed significantly lower peel strength than those of other groups (3.1±0.6 MPa).

CONCLUSION

Heat-cured acrylic resin, PMMA, may benefit from Er,Cr:YSGG laser treatment at 3 W-20 Hz irradiation. Air-abrasion of polyamide resins should be avoided not to impair their peel bond strengths to silicon-based soft denture liners.