Relationship between tear eotaxin-2 and MMP-9 with ocular allergy and corneal topography in keratoconus patients

International Ophthalmology - To analyze the relationship between the seasonal allergic conjunctivitis (SAC), eotaxin-2, matrix metalloproteinase-9 (MMP-9), and the topographical findings in the...     

Learning Effects Associated With the Least Stable Level of the Biodex? Stability System During Dual and Single Limb Stance

The Biodex® Stability System (BSS) has high test-retest reliability when stable (high) resistance levels are used. However, reliability data for lower stability levels, associated with more pronounced learning curves, are rare in the existing literature. Thus, it is likely that BSS scores obtained from lower stability levels require greater familiarization (i.e. practice) to achieve a stable score both within and between test sessions. Therefore, the purpose of this investigation was to determine if a commonly reported 6 trial sequence (3 practice trials, 3 test trials) used with the BSS can achieve a stable within session score on the lowest stability level (i.e. level 1). The secondary purpose was to evaluate the test-retest reliability of the lowest BSS resistance level over a 10-week period. Twenty sedentary university students (11 male, 9 female; age: 21.5 ± 1.9 years, height: 1.7 ± 0.1 m, weight: 66.3 ± 12.1 kg, BMI: 22.4 ± 2.3) voluntarily participated. Participants completed two test sessions separated by 10-weeks. Twelve, 20-second trials (six dual limb stance, six single limb stance on the dominant limb) on the lowest stability level were completed during both test sessions by all participants. A stable within session dual and single limb stance score was achieved with a maximum of 3 familiarization trials. Reliability ranged between poor and good across all outcomes but all outcomes had large minimal detectable change scores. At least 3 stance specific familiarization trials are needed to achieve a stable BSS score within a single test session on the lowest resistance level. However, the inconsistent reliability and high minimal detectable changes scores suggest that the lowest resistance level should not be used as an objective marker of rehabilitation progress over extended periods of time (e.g. 10-weeks).

Key points

• Level 1 BSS scores should not be used as a test setting to assess rehabilitation.
• Familiarization trials should not be underestimated by researchers/clinicans.
• Lower stability levels on the BSS may not be appropriate for use as an objective marker of progression due to poor reliability of the scores over time.

Key Words: Practice, postural control, test-retest reliability     

Influence of Hydrofluoric and Nitric Acid Pre-Treatment and Type of Adhesive Cement on Retention of Zirconia Crowns

Background: The aim of this study was to test the impact of hot acids etching and two types of adhesive cement on the retention of zirconia crowns. Methods: Forty maxillary premolars were prepared, and zirconia crowns were designed and fabricated with proximal extensions, then divided into 4 groups (n = 10). Group AP; the crowns were air-abraded and cemented using Panavia SA Cement. Group AL; the crowns were air- abraded and cemented using GC LinkForce. Group AHP; the crowns were air-abraded, etched with the hot acids (48% hydrofluoric acid and 69% nitric acid), and cemented using Panavia SA Cement. Group AHL; the crowns were air-abraded, etched with the hot acids, and cemented using GC LinkForce. Each zirconia crown was pre-treated and bonded to its corresponding tooth. After thermocycling (5–55 °C/10,000), the retention test was performed and the load required to dislodge the crown was reported in Newton (N), and mode of failure was recorded. The retention strength (MPa) was calculated for each tested variable and statistically analyzed. Results: Group AHP showed the highest mean value of the retention strength, followed by group AP then group AHL. Group AL showed the lowest value. A statistically significant effect (p = 0.001) of the hot acids etching on the retention of zirconia crown was found. Also, there was a significant effect (p = 0.000) of the cement type. The interaction between surface treatment and the cement type has no significant impact (p = 0.882). The main mode of failure for Panavia SA Cement is mixed mode of failure, while for G-CEM LinkForce is adhesive failure. Conclusions: Hot acid etching pre-treatment improved the retention of zirconia crown. Usage of Panavia SA Cement with hot acids etching is effective can be used for adhesive cementation of zirconia crown.     

Effect of Non-Thermal Atmospheric Plasma on Micro-Tensile Bond Strength at Adhesive/Dentin Interface: A Systematic Review

Objective: The objective of this review was to evaluate the effect of non-thermal atmospheric plasma (NTAP) on adhesives resin–dentin micro-tensile bond strength (μTBS) in previously published studies. Methods: Electronic search was conducted using the Medline, Cochrane library, and Scopus databases. The included studies were laboratory studies that investigated the effect of NTAP on adhesives μTBS to coronal dentin. Studies that evaluated the effect of NTAP on bond strength to indirect substrates, enamel or root dentin, were excluded. The methodological quality of included studies was assessed. Results: Thirteen studies were included in this systematic review. All the included studies were considered to have a medium risk of bias. NTAP significantly improved μTBS at 24 h or after short-term aging in five studies (38.5%) and both immediate and after long-term aging in 5 studies (38.5%). In two studies (15.4%), NTAP resulted in a short-term material-dependent effect that was not stable after long-term aging. Interestingly, in one study (7.7%), NTAP had a positive effect only in the etch-and-rinse (ER) mode after long-term aging. Conclusion: Within the limitations of this systematic review, NTAP application could enhance resin–dentin μTBS of ER adhesives or universal adhesives (UAs) applied in the ER mode. In the ER mode, the rewetting step after NTAP seems to be unnecessary. Because of the limited information currently available in the literature, further studies are required to evaluate the effect of the NTAP application on self-etch (SE) adhesives or UAs applied in the SE mode.     

Chemical composition of the essential oil and n-hexane extract of Stachys tmolea subsp. Tmolea Boiss., an endemic species of Turkey,and their mosquitocidal activity against dengue vector Aesdes aegypti

Stachys tmolea subsp. tmolea Boiss. is endemic to Turkey and is a species of the genus Stachys L. which is one of the largest genera of the family Lamiaceae with about 300 species. The aims of this study were to examine the chemical composition of the essential oil and n-hexane extract of S. tmolea subsp. tmolea as natural sources of insecticidal activity against the dengue vector, Aedes aegypti. Analysis of the essential oil by GC-FID and gas chromatography-mass spectrometry (GC-MS) systems identified hexahydrofarnesyl acetone (15%), viridiflorol (10%), hexadecanoic acid (7%) and 9-geranyl-p-cymene (6%) as major components. The volatile components of the n-hexane extract were extracted using headspace solid-phase microextraction (HS-SPME) and were analyzed using GC-MS. The principal constituents were 3,4-dimethyl decane (16%), 3-methyl-3-pentanol (15%), 2-methyl-2-pentanol (12%), 1,4-bis (1,1-dimethylethyl) benzene (12%), heptanal (10%), acetic acid (6%) and decane (4%). Bioassay of the n-hexane extract, at 5 µg/mosquito, produced 90% mortality against adult Ae. aegypti while the S. tmolea essential oil demonstrated 13% mortality. No larvicidal activity was observed both in essential oil and n-hexane extract. Further studies are needed to assess the adulticidal activity of the responsible compounds in the crude extract.     

Fracture load of CAD/CAM-fabricated and 3D-printed composite crowns as a function of material thickness

Clinical Oral Investigations - Indirect CAD/CAM restorations can be fabricated using both subtractive and additive CAD/CAM technology. This study investigated the fracture load of crowns fabricated...