Effect of water storage on flexural strength of silorane and methacrylate-based composite resins

Panahandeh, Narges,Torabzadeh, Hassan,Naderi, Hani,Sheikh-Al-Eslamian, Seyedeh Mahsa The Korean Academy of Conservative Dentistry 2017 Restorative Dentistry & Endodontics Vol.42 No.4

Objectives: This study assessed the effect of water storage on the flexural strength (FS) of low shrinkage composites. Materials and Methods: A total of 165 bar-shaped specimens ($2{\times}2{\times}25mm$) were fabricated of 2 low shrinkage composites (Filtek P90 [3M ESPE], GC Kalore [GC International]) and a conventional methacrylate-based composite (Filtek Z250 [3M ESPE]). The specimens were subjected to 3-point bending test at 6 time intervals, namely: immediately after curing, at 24 hours, 1 week, 1 month, 6 months, and 1 year following storage in wet and dry conditions. The FS of the specimens were measured by applying compressive load at a crosshead speed of 1.0 mm/min. Data was analyzed using 3-way analysis of variance (ANOVA) and Tukey's test. Results: Three-way ANOVA revealed significant interactions between time, type of composite, and storage condition (p = 0.001). Tukey's multiple comparison test revealed significant reductions in FS of all composites after 6 months and 1 year of storage in distilled water compared to dry condition. Conclusions: Filtek P90 showed the highest and GC Kalore showed the lowest FS after 1 year storage in distilled water. The immediate high strength of Filtek Z250 significantly decreased at 1 year and its final value was lower than that of Filtek P90.

Effect of water storage on flexural strength of silorane and methacrylate-based composite resins

Narges Panahandeh,Hassan Torabzadeh,Hani Naderi,Seyedeh Mahsa Sheikh-Al-Eslamian 대한치과보존학회 2017 Restorative Dentistry & Endodontics Vol.42 No.4

Objectives: This study assessed the effect of water storage on the flexural strength (FS) of low shrinkage composites. Materials and Methods: A total of 165 bar-shaped specimens (2 × 2 × 25 mm) were fabricated of 2 low shrinkage composites (Filtek P90 [3M ESPE], GC Kalore [GC International]) and a conventional methacrylate-based composite (Filtek Z250 [3M ESPE]). The specimens were subjected to 3-point bending test at 6 time intervals, namely: immediately after curing, at 24 hours, 1 week, 1 month, 6 months, and 1 year following storage in wet and dry conditions. The FS of the specimens were measured by applying compressive load at a crosshead speed of 1.0 mm/min. Data was analyzed using 3-way analysis of variance (ANOVA) and Tukey's test. Results: Three-way ANOVA revealed significant interactions between time, type of composite, and storage condition (p = 0.001). Tukey's multiple comparison test revealed significant reductions in FS of all composites after 6 months and 1 year of storage in distilled water compared to dry condition. Conclusions: Filtek P90 showed the highest and GC Kalore showed the lowest FS after 1 year storage in distilled water. The immediate high strength of Filtek Z250 significantly decreased at 1 year and its final value was lower than that of Filtek P90.

Bioactivity of endodontic biomaterials on dental pulp stem cells through dentin

Javid, Bahar,Panahandeh, Narges,Torabzadeh, Hassan,Nazarian, Hamid,Parhizkar, Ardavan,Asgary, Saeed The Korean Academy of Conservative Dentistry 2020 Restorative Dentistry & Endodontics Vol.45 No.1

Objectives: This study investigated the indirect effect of calcium-enriched mixture (CEM) cement and mineral trioxide aggregate (MTA), as 2 calcium silicate-based hydraulic cements, on human dental pulp stem cells (hDPSCs) through different dentin thicknesses. Materials and Methods: Two-chamber setups were designed to simulate indirect pulp capping (IPC). Human molars were sectioned to obtain 0.1-, 0.3-, and 0.5-mm-thick dentin discs, which were placed between the 2 chambers to simulate an IPC procedure. Then, MTA and CEM were applied on one side of the discs, while hDPSCs were cultured on the other side. After 2 weeks of incubation, the cells were removed, and cell proliferation, morphology, and attachment to the discs were evaluated under scanning electron microscopy (SEM). Energy-dispersive X-ray (EDXA) spectroscopy was performed for elemental analysis. Alkaline phosphatase (ALP) activity was assessed quantitatively. The data were analyzed using the Kruskal-Wallis and Mann-Whitney tests. Results: SEM micrographs revealed elongated cells, collagen fibers, and calcified nucleations in all samples. EDXA verified that the calcified nucleations consisted of calcium phosphate. The largest calcifications were seen in the 0.1-mm-thick dentin subgroups. There was no significant difference in ALP activity across the CEM subgroups; however, ALP activity was significantly lower in the 0.1-mm-thick dentin subgroup than in the other MTA subgroups (p < 0.05). Conclusions: The employed capping biomaterials exerted biological activity on hDPSCs, as shown by cell proliferation, morphology, and attachment and calcific precipitations, through 0.1- to 0.5-mm-thick layers of dentin. In IPC, the bioactivity of these endodontic biomaterials is probably beneficial.

Bioactivity of endodontic biomaterials on dental pulp stem cells through dentin

Bahar Javid,Narges Panahandeh,Hassan Torabzadeh,Hamid Nazarian,Ardavan Parhizkar,Saeed Asgary 대한치과보존학회 2020 Restorative Dentistry & Endodontics Vol.45 No.1

Objectives: This study investigated the indirect effect of calcium-enriched mixture (CEM) cement and mineral trioxide aggregate (MTA), as 2 calcium silicate-based hydraulic cements, on human dental pulp stem cells (hDPSCs) through different dentin thicknesses. Materials and Methods: Two-chamber setups were designed to simulate indirect pulp capping (IPC). Human molars were sectioned to obtain 0.1-, 0.3-, and 0.5-mm-thick dentin discs, which were placed between the 2 chambers to simulate an IPC procedure. Then, MTA and CEM were applied on one side of the discs, while hDPSCs were cultured on the other side. After 2 weeks of incubation, the cells were removed, and cell proliferation, morphology, and attachment to the discs were evaluated under scanning electron microscopy (SEM). Energy-dispersive X-ray (EDXA) spectroscopy was performed for elemental analysis. Alkaline phosphatase (ALP) activity was assessed quantitatively. The data were analyzed using the Kruskal-Wallis and Mann-Whitney tests. Results: SEM micrographs revealed elongated cells, collagen fibers, and calcified nucleations in all samples. EDXA verified that the calcified nucleations consisted of calcium phosphate. The largest calcifications were seen in the 0.1-mm-thick dentin subgroups. There was no significant difference in ALP activity across the CEM subgroups; however, ALP activity was significantly lower in the 0.1-mm-thick dentin subgroup than in the other MTA subgroups (p < 0.05). Conclusions: The employed capping biomaterials exerted biological activity on hDPSCs, as shown by cell proliferation, morphology, and attachment and calcific precipitations, through 0.1- to 0.5-mm-thick layers of dentin. In IPC, the bioactivity of these endodontic biomaterials is probably beneficial.

Assessment of Iranian Rainfed and Seedy Watermelon Landraces as Potential Rootstocks for Enhancing Drought Tolerance

Ali Parsafar,Jaber Panahandeh,Davoud Zarehaghi 한국원예학회 2019 원예과학기술지 Vol.37 No.3

We conducted this study over the course of two consecutive growing seasons to evaluate the response of watermelon (Citrullus lanatus (Thunb.) Matsum. et Nakai cv. Crimson Sweet) to grafting onto three Iranian rainfed and seedy watermelon landraces collected from Khaje, Sabzevar, and Ashtian, along with ‘Shintoza’ (Cucurbita maxima × Cucurbita moschata) seedlings as a rootstock for watermelon. Soil moisture content [percentage of field capacity (FC)] was determined by time domain reflectometry (TDR). Irrigation was applied in three different levels based on FC as 0.8FC-FC, 0.6FC-0.8FC and 0.3FC-0.6FC by furrow irrigation method. Yield, shoot dry weight, fruit quality, chlorophyll index, phenolic compounds, relative water content (RWC), electrolyte leakage, and proline concentration were measured at the end of both growing seasons. The results showed that the highest fruit yield (9.4 kg) and shoot dry weight (390.8 g) were obtained in watermelons grafted onto Shintoza rootstock in 0.8FC-FC. The lowest fruit yield (1.4 kg) and shoot dry weight (55.6 g) were observed in un-grafted controls and in 0.3FC-0.6FC. Fruit quality in watermelons grafted onto Shintoza rootstock was significantly different compared to the other grafting combinations and the un-grafted control. Chlorophyll index, phenolic compounds, RWC, electrolyte leakage, and proline were significantly affected by irrigation regimes. Shintoza and Sabzevar grafting combinations showed high levels of chlorophyll index, phenolic compounds, and RWC as compared to un-grafted plants and Ashtian grafting combination.

Shade reproduction and the ability of lithium disilicate ceramics to mask dark substrates

Iravani, Maryam,Shamszadeh, Sayna,Panahandeh, Narges,Sheikh-Al-Eslamian, Seyedeh Mahsa,Torabzadeh, Hassan The Korean Academy of Conservative Dentistry 2020 Restorative Dentistry & Endodontics Vol.45 No.3

Objectives: This study aimed to evaluate the ability of lithium disilicate ceramics to reproduce the A2 shade and to mask A4 substrates. Materials and Methods: Twenty-four discs (8 mm in diameter, shade A2) of high translucency (groups 1-3) and low translucency (groups 4-6) of IPS e.max ceramic with different thicknesses (0.5, 0.75, and 1 mm) were fabricated as monolithic structures. In addition, discs of medium opacity (group 7-8) with different core/veneer combinations (0.3 mm/0.7 mm and 0.5 mm/0.5 mm) were fabricated as bilayer structures. Specimens were superimposed on an A4 substrate (complex). The color changes of the complex were measured using a spectrophotometer on a black background, and the ΔE values of the complex were compared with either the A4 substrate or the A2 shade tab. One-way analysis of variance, the Tukey honest significant difference test, and the Fisher test were used to analyze the data (p < 0.05). Results: Significant between-group differences were found for comparisons to both the A4 substrate and the A2 shade (p < 0.05). When compared with the A4 substrate, the ΔE values in all groups were in the non-acceptable range. When compared with the A2 shade, the ΔE values in all groups, except groups 2 and 3, were in the clinically acceptable range. Conclusions: All translucencies and thicknesses masked the underlying dark substrate. However, the low-translucency IPS e.max Press better reproduced the A2 shade.

Comparing the effects of vaginal misoprostol, laminaria, and extra amniotic saline infusion on cervical ripening and induction of labor

( Zohreh Tabasi ),( Elaheh Mesdaghinia ),( Masoumeh Abedzadeh-kalahroudi ),( Mojtaba Sehat ),( Aida Panahandeh ) 대한산부인과학회 2020 Obstetrics & Gynecology Science Vol.63 No.3

Objective This study aimed to compare the effects of vaginal misoprostol, laminaria, and extra-amniotic saline infusion (EASI) on cervical ripening. Methods This randomized controlled trial was conducted on 195 women with singleton pregnancies and unripe cervices. Participants were randomly allocated to 3, 65-person groups: a misoprostol, a laminaria, and an EASI group. The interventions in the misoprostol, laminaria, and EASI groups included a single 25-μg vaginal misoprostol suppository, an intracervical laminaria, and a transcervical Foley catheter, respectively. The groups were compared with each other regarding time intervals from labor induction to labor active phase and delivery, cervical dilation, Bishop scores 6 hours after induction, delivery type, length of hospital stay, and complications. Results There were no significant differences among the groups regarding maternal ages, gestational ages, body mass indices, baseline cervical dilations, and Bishop scores (P>0.05). Six hours after induction, the Bishop score and cervical dilation were significantly greater in the EASI group than in the other 2 groups (P<0.001). Moreover, time intervals from labor induction to labor active phase and delivery in the EASI group were significantly short (P<0.001). The rates of cesarean section, fetal distress, placental abruption, and meconium staining in the misoprostol group were significantly high (P<0.05), and the length of hospital stay in the EASI group was significantly short (P<0.001). Conclusion EASI is a safer and more effective method for cervical ripening. Considering its inexpensiveness, easy accessibility, and greater effectiveness, EASI is recommended for cervical ripening.

Effects of 3 different light-curing units on the physico-mechanical properties of bleach-shade resin composites

Farzad Azin,Kasraei Shahin,Haghi Sahebeh,Masoumbeigi Mahboubeh,Torabzadeh Hassan,Panahandeh Narges 대한치과보존학회 2022 Restorative Dentistry & Endodontics Vol.47 No.1

Objectives This study investigated the microhardness, flexural strength, and color stability of bleach-shade resin composites cured with 3 different light-curing units. Materials and Methods In this in vitro experimental study, 270 samples were fabricated of bleach and A2 shades of 3 commercial resin composites (Point 4, G-aenial Anterior, and Estelite Sigma Quick). Samples (n = 5 for each trial) were cured with Bluephase N, Woodpecker LED.D, and Optilux 501 units and underwent Vickers microhardness and flexural strength tests. The samples were tested after 24 hours of storage in distilled water. Color was assessed using a spectrophotometer immediately after preparation and 24 hours after curing. Data were analyzed using 3-way analysis of variance and the Tukey test (p ≤ 0.001). Results Samples cured with Optilux exhibited the highest and those cured with LED.D exhibited the lowest microhardness (p = 0.023). The bleach shade of Point 4 composite cured with Optilux displayed the highest flexural strength, while the same composite and shade cured with Sigma Quick exhibited the lowest (p ≤ 0.001). The color change after 24 hours was greatest for the bleach shade of G-aenial cured with Bluephase N and least for the A2 shade of Sigma Quick cured with Optilux (p ≤ 0.001). Conclusions Light curing with polywave light-emitting diode (LED) yielded results between or statistically similar to those of quartz-tungsten-halogen and monowave LED in the microhardness and flexural strength of both A2 and bleach shades of resin composites. However, the brands of light-curing devices showed significant differences in color stability. Objectives This study investigated the microhardness, flexural strength, and color stability of bleach-shade resin composites cured with 3 different light-curing units. Materials and Methods In this in vitro experimental study, 270 samples were fabricated of bleach and A2 shades of 3 commercial resin composites (Point 4, G-aenial Anterior, and Estelite Sigma Quick). Samples (n = 5 for each trial) were cured with Bluephase N, Woodpecker LED.D, and Optilux 501 units and underwent Vickers microhardness and flexural strength tests. The samples were tested after 24 hours of storage in distilled water. Color was assessed using a spectrophotometer immediately after preparation and 24 hours after curing. Data were analyzed using 3-way analysis of variance and the Tukey test (p ≤ 0.001). Results Samples cured with Optilux exhibited the highest and those cured with LED.D exhibited the lowest microhardness (p = 0.023). The bleach shade of Point 4 composite cured with Optilux displayed the highest flexural strength, while the same composite and shade cured with Sigma Quick exhibited the lowest (p ≤ 0.001). The color change after 24 hours was greatest for the bleach shade of G-aenial cured with Bluephase N and least for the A2 shade of Sigma Quick cured with Optilux (p ≤ 0.001). Conclusions Light curing with polywave light-emitting diode (LED) yielded results between or statistically similar to those of quartz-tungsten-halogen and monowave LED in the microhardness and flexural strength of both A2 and bleach shades of resin composites. However, the brands of light-curing devices showed significant differences in color stability.