bluuebunny/crossref_metadata_2025 huggingface dataset:
Properties of Gelatin/Carbonate Apatite Composite Compared to Bovine Bone
Authors: Khanna Prachi , LeGeros Racquel Z.
Published: November 2012

Bone is a composite of approximately 65% inorganic phase (carbonate apatite, CHA) and a 35% organic phase (mostly collagen). To date, several commercial composites consisting of natural or synthetic polymers and calcium phosphates ( hydroxyapatite, tricalcium phosphate, biphasic calcium phosphates) are recommended for use in bone repair. Objective: The aim of this study was to compare the physico-chemical properties of gelatin/carbonate apatite composites with that of bovine bone. Native (Gel) or cross-linked (Gel*) was used. Methods: The CHA was prepared by hydrolysis method. The gelatin (denatured collagen) was cross-linked using Genipin. The gelatin/CHA composite were prepared by mixing of 35% gelatin and 65% CHA and freeze-drying. The composites were characterized using x-ray diffraction (XRD), FT-IR spectroscopy, scanning electron microscopy (SEM) and thermogravimetry (TGA). Dissolution properties were determined in acidic buffer (0.1M KAc, pH 6, 37°C). Mechanical strength was determined using 3-point bend test. Bovine bone was similarly characterized for comparison. Results: The composition and crystallite size of the CHA were similar to that of the bone mineral. The Gel/CHA and Gel*/CHA composites showed several physico-chemical properties (crystallinity, composition, thermal stability, mechanical strength, dissolution rate) similar to that of bone. Gel*/CHA compared to Gel/CHA composites showed lower elastic modulus, flexural strength, dissolution rate, swelling and higher porosity. Conclusion: The Gel*/CHA composites presented several properties similar to those of bovine bone and may have potential as bone substitute materials.
Development and Characterization of Poly(ε-caprolactone) Reinforced Porous Hydroxyapatite for Bone Tissue Engineering
Authors: Phanny Yos , Todo Mitsugu
Published: November 2012

Hydroxyapatite (HA) scaffold was fabricated using template method. Secondary phase of poly (ε-caprolactone) (PCL) was then introduced into the porous structure of the HA scaffold by the freeze drying method or the room drying process. Compression test and SEM were done to examine the mechanical properties and the microstructural morphology of the composite scaffolds. It was found that the compressive strength and modulus tend to increase with increasing PCL concentration. HA/PCL scaffolds fabricated under the room drying process exhibited higher compression strength and modulus than HA/PCL scaffolds prepared by the freeze drying method because the porous HA surfaces were completely covered by PCL in the room drying scaffolds. XRD test was also used to study the phase stability of the scaffolds. It was confirmed that there was no chemical reaction between PCL and HA. On overall, the results indicated that the introduction of secondary PCL phases into the porous HA scaffold can improve the low strength and toughness of the pure HA scaffold and the HA/PCL composite scaffolds might be a potential candidate in bone tissue engineering.
The Controlled Release of Simvastatin from Biomimetic Macrospheres
Authors: Chou Joshua , Ito Tomoko , Otsuka Makoto , Ben-Nissan Besim , Milthorpe Bruce
Published: November 2012

Simvastatin has been shown to succesfully stimulate bone regeneration and attention has being focussed on developing appropriate delivery carriers for its release. The challenge of deliverying therapeutic concentration of pharmaceutical compunds has being the centre of focus in drug delivery developments. This study examines the in-vivo effects of simvastatin released from β-TCP macrospheres derived from coral exoxskeletons. The results indicates that the controlled release of simvastatin can promote bone formation comparable with direct injection. Furthermore the results showed that the release of simvastatin delivery rates can be controlled by additional coating of an apatite coating. Analysis by CT scans, SEM, amount of new bone formed and mechanical strength tests, showed that by controlling the release of simvastatin bone formation can be stimulated to a therapeutic level.
Novel Apatite-Pathogen-Associated Molecular Patterns Adjuvants for Cancer Immune Therapy
Authors: Wang Xiu Peng , Li Xia , Ito Atsuo , Sogo Yu
Published: November 2012

An apatite-pathogen-associated molecular patterns (PAMPs) adjuvant was prepared by coprecipitation of apatite and PAMPs using a supersaturated calcium phosphate solution supplemented with PAMPs. In this study, we used a hydrothermal extract of human tubercle bacillus (HTB) as PAMPs. The effects of coprecipitation conditions on immunogenic activity were studied. The adjuvants prepared using extract of at 10 and 20 μg/mL showed higher in vitro immunogenic activity than that at 2 μg/mL. The adjuvants prepared under stir at speed of 300 rpm showed better in vitro immunogenic activity than those under still. The adjuvants prepared using 10 μg/mL of extract of HTB under stir at speed of 300 rpm may be promising for cancer immune therapy.
Surface Properties of Dental Zirconia after Clinical Grinding and Polishing
Authors: Ban Seiji , Sakakibara Tohru , Yoshihara Kentaro , Takeuchi Masami , Kawai Tatsushi , Murakami Hiroshi , Kono Hiroshi
Published: November 2012

Three kinds of dental zirconia (Cercon, NANOZR, and P-NANOZR) were ground and polished with seven kinds of clinical device and materials. After these grinding and polishing, the surface roughness and the glossiness were analyzed. The crystal phases of the surface were analyzed with a micro X-ray diffractometer. The results demonstrated that all three zirconia showed the smallest roughness and the highest glossiness when they were polished with diamond-containing polishing pastes. Tetragonal to rhombohedral transformation was observed on the ground and polished surfaces of Cercon and ZENOSTAR, whereas monoclinic phase was also detected on the ground and polished surface of P-NANOZR. The polishing with diamond-containing pastes showed the smallest transformation amount of rhombohedral and monoclinic phases. It is concluded that dental zirconia can be well polished with diamond-containing pastes, and the phase transformation are also reduced.
Factors Affecting on the Bond Strength of Dental Zirconia to Veneering Porcelains
Authors: Tsuruki Jiro , Kono Hiroshi , Okuda Yuji , Noda Makoto , Arikawa Hiroyuki , Kanie Takahito , Ban Seiji
Published: November 2012

The bond strengths between two kinds of zirconia and three kinds of feldspathic veneering porcelains were measured. The specimens were prepared at four firing temperatures for three holding periods, respective opaque porcelain was painted and vacuum-fired. Then, each dentin porcelain was condensed in an acrylic resin mold and vacuum-fired under the conditions mentioned above. Cross sections of the interface between zirconia and porcelain were observed with a scanning electron microscope. The specimens were fixed to specimen holder on a universal testing machine. Data of the bonding test were statistically analyzed. The results showed that all the four factors statistically affected the bonding strength (p<0.01). The contribution of the firing temperature was highest and that of the porcelain type was lowest (p<0.01).
Visible Light-Induced Crosslinkable Gelatin for Direct Pulp Capping
Authors: Nakamura Mariko , Yoshida Yasuhiro , Ito Yoshihiro
Published: November 2012

Direct pulp capping involves the application of dental materials to the exposed pulp in an attempt to act as a barrier, protect the dental pulp complex and preserve its vitality. The materials for direct pulp capping should ideally adhere to dental pulp tissue as soft tissue and dentin as hard tissue with tight sealing. We therefore developed visible light-induced crosslinkable gelatin which is capable of adhesive to soft tissue and hard tissue.
Bioactive Ti Metal with Ca-Enriched Surface Layer Able to Release Zn Ion
Authors: Yamaguchi Seiji , Matsushita Tomiharu , Nakamura Takashi , Kokubo Tadashi
Published: November 2012

Preparation of bioactive titanium (Ti) metal able to release Zn2+ ions was attempted by chemical and heat treatments of Ti metal. Ti metal was soaked in 5M NaOH solution at 60 °C to form sodium hydrogen titanate (SHT) on its surface. Then, it was soaked in a mixed solution of 100 mM Ca(CH3COO)2 and 0.01 - 1 mM Zn (CH3COO)2 at 40 °C for 24 h to replace Na+ ions in SHT with Ca2+ and Zn2+ ions at given range of 0.15 to 2.95 in Zn/Ca ratio. When it was heat-treated at 600 °C for 1 h, zinc-incorporated calcium titanate (ZCT) and rutile were formed on the surface of Ti metal. The ZCT partially replaced its Ca2+ and Zn2+ ions with H3O+ ions by subsequent soaking in 1 mM acetic acid solution at 80 °C. Thus treated Ti metal formed apatite on its surface in a simulated body fluid (SBF) within 3 days, and slowly released Zn2+ ions into phosphate-buffered solution (PBS) up to 0.03 ppm. The Ti metal formed with this kind of bioactive ZCT layer on its surface is expected to be useful as orthopedic and dental implants, since it could bond to living bone sooner, by promoting formation of the surrounding bone.
Fabrication of Bioactive Apatite Nuclei-Precipitated Titanium Alloys by Using Sandblasting
Authors: Mizuno Hiroshi , Yabutsuka Takeshi , Yao Takeshi
Published: November 2012

Micropores were formed on the surface of Ti metal, Ti-15Mo-5Zr-3Al alloy, Ti-12Ta-9Nb-3V-6Zr-O alloy plate by doubled sandblasting process using silicon carbide particles with 14.0 μm for average particle size as first process, then using the particles with 3.0 μm for average particle size as second process. Apatite Nuclei (AN) were precipitated in the pores. By these treatments, bioactive AN-precipitated Ti alloys were fabricated. Bioactivity of the AN-precipitated Ti alloys was examined by soaking in SBF and it was observed that hydroxyapatite was induced on the surface of the Ti alloys within 1 d. High adhesive strength of hydroxyapatite layer was achieved due to a mechanical interlocking effect between hydroxyapatite formed in the micropores and the plate.
Enhancement of Calcium Phosphate Formation on Zirconium by Combination of Simple Electrochemical Treatments
Authors: Tsutsumi Yusuke , Doi Hisashi , Nomura Naoyuki , Kim Kyo Han , Hanawa Takao
Published: November 2012

Electrochemical surface treatments of micro-arc oxidation (MAO) and following cathodic polarization were performed on zirconium (Zr) disks in this study to enhance the bioactivity of Zr. The surface oxide layers formed with electrochemical treatments on Zr disks were characterized using surface analyses; the calcium phosphate formation on the specimens after immersion in Hanks’ solution was evaluated. As a result, thick calcium phosphate layers formed on only Zr specimens that underwent both MAO treatment with a mixture of calcium glycerophosphate and magnesium acetate and subsequent cathodic polarization treatment with sodium sulfate solution, while no precipitate was observed without treatment. Thus, this technique was confirmed to be a promising method to improve the bioactivity of Zr.
Effect of Autoclave and Hot Water Treatment on Surface Structure and Apatite-Forming Ability of NaOH- and Heat-Treated Titanium Metals in Simulated Body Fluid
Authors: Masakazu Kawashita , Matsui N. , Miyazaki Toshiki , Kanetaka Hiroyasu
Published: November 2012

Sodium hydroxide (NaOH)-, heat- and autoclave-treated Ti metal did not form apatite in simulated body fluid (SBF) within 7 days although certain amounts of sodium (Na) still remained on the Ti metal surface even after the autoclave treatment. When hot water treatment was applied between NaOH and heat treatment, the Ti metal formed apatite within 7 days in SBF. Anatase-type TiO2 was partially precipitated by the NaOH and heat treatment but it was disappeared by the subsequent autoclave treatment. When the hot water treatment was applied between the NaOH and heat treatment, considerable amount of anatase-type TiO2 was formed and it still remained even after the autoclave treatment. The zeta potential of the Ti metal with the hot water treatment was almost zero in SBF. These results indicate that Ti metal can show apatite-forming ability in SBF even after autoclave treatment, when hot water treatment is applied between the NaOH and heat treatment, and that anatase-type TiO2 might play an important role in the apatite formation rather than the amount of Na and/or the zeta potential.
The Effects of the Coating of Anodized Titanium with Multi-Walled Carbon Nanotubes on Bone Formation
Authors: Inoue Saori , Uo Motohiro , Sakairi Masatoshi , Hirata Eri , Lee Min Ho , Bae Tae Sung , Akasaka Tsukasa , Watari Fumio , Yokoyama Atsuro
Published: November 2012

Carbon nanotubes (CNTs) have excellent chemical, physical, and biological properties such as strong cell adhesion, protein adsorption and cell proliferation in vitro. Excellent osteocompatibility for the CNT monolith was also reported in vivo. The purpose of this study was to evaluate the effects of anodized titanium coated with multiwalled CNTs (MWCNTs) on human osteosarcoma Saos2 cells and bone tissue. Saos2 cells on CNT-Ti showed excellent proliferation with extension of cell morphology in all directions. CNT-Ti wire was implanted in the bone marrow of femurs of rats. At 2 weeks after surgery, histological investigations revealed that bone tissue attached to the surface of the CNT-Ti directly. Thus the surface modification of anodized Ti by MWCNTs can be effective for bone formation.
Testing of the Extended Tao-Eldrup Model on Porous VP-DVB Copolymers
Authors: Gorgol Marek , Maciejewska Małgorzata , Jasińska Bożena , Zaleski Radosław
Published: November 2012

Five samples of porous polymers were investigated using positron annihilation lifetime spectroscopy and liquid nitrogen sorption techniques. Temperature dependencies of o-Ps lifetime were used to estimate the ETE model parameters (R and Δ) for porous polymers. The value of the Δ parameter was found to be 0.13-0.15 nm. A significant difference between pore radii obtained by both techniques was found.
Paramagnetic Behaviour in RE2W2O9 Tungstates (RE = Pr, Nd, Sm – Gd)
Authors: Mazur Slawomir , Tomaszewicz Elzbieta , Groń Tadeusz , Duda Henryk , Kukuła Zenon , Mydlarz Tadeusz
Published: November 2012

Magnetic susceptibility measurements revealed a disordered state of magnetic moments above 4.2 K for all compounds under study, and a weak response to the magnetic field and the temperature for Sm2W2O9 and Eu2W2O9 tungstates. The temperature independent component of magnetic susceptibility has a positive value for RE2W2O9 (RE = Pr, Nd and Gd) indicating a domination of van Vleck contribution. Only for Gd2W2O9 the magnetization is a universal function of µ0H/T, characteristic for the superparamagnetism.
Magnetostriction of First and Second Order Magnetite Samples and its Relation to the Magnetic Easy Axis Switching
Authors: Britwum Akyana , Kolodziej Tomasz , Tokarz Waldemar , Przewoźnik Janusz , Kapusta Czesław , Kąkol Zbigniew , Kozłowski Andrzej , Tarnawski Zbigniew , Honig Jurgen M.
Published: November 2012

Magnetic field (up to 8T) and temperature (10-300K) dependence of size of Zn doped magnetite samples Fe3-xZnxO4 (x=0.008, 0.022, i.e. falling within first and second order Verwey transition regime) were measured by the strain gauge method. Both samples experienced shrinking on cooling through the Verwey transition along monoclinic c axis, while the strong expansion was found for the 1st order sample in the a-b direction, unlike in the 2nd order sample. Magnetostriction of both samples is very small and limited to low fields only, concomitant with magnetization process. However, field application perpendicular to c axis and at T slightly below the Verwey transition temperature TV results in a large change of dimensions, coinciding with the axis switching process.
Superhard Composite Containing Boron Nitride and Silicon Nitride
Authors: Skury Ana Lúcia Diegues , Chagas Shirlene , Monteiro Sérgio Neves
Published: November 2012

As a superhard material, next to diamond, the cubic boron nitride (cBN) is of great interest owing to its efficiency in machining ferrous alloys. In nature, only the hexagonal, hBN, exists. In practice, high pressure and high temperature (HPHT) synthesis has to be used to produce small cBN crystals. For larger size machining inserts, the powder-like cBN crystals need to be sintered at specific HPHT conditions using a metallic binder. The present work investigates the sintering of cBN inserts using a Si3N4 binder agent. The results disclosed relatively high hardness for the inserts and revealed their effectiveness in machining high strength steels.
Effects of La2O3 Addition on the Microstructure and Properties of Activated Sintered W-Ni Compacts
Authors: Balci Özge , Demirkan Ö. Utku , Agaogullari Duygu , Gokce Hasan , Genç Aziz , Öveçoğlu M. Lütfi , Duman Ismail
Published: November 2012

In order to improve the properties of Ni activated sintered W compacts, La2O3 was added to a W-1 wt.% Ni matrix alloy. W-1 wt.% Ni-0.5 wt.% La2O3 and W-1 wt.% Ni-1 wt.% La2O3 composites were fabricated by mechanical alloying and activated sintering methods. The effects of La2O3 content and mechanical alloying duration on the microstructural and physical properties of activated sintered W-Ni compacts were investigated. The results showed that La2O3 particles have a significant effect on the density/microhardness values and wear amounts of the samples. The relative density value of 96.39 % and microhardness value of 4.08±0.28 GPa of W-1 wt.% Ni samples increased to respectively 98.09 % and 5.45±0.29 GPa with the addition of 1 wt.% La2O3. Wear rate of 3.26±0.81 (mm3N-1m-1)x10-9 of the W-1 wt% Ni samples decreased to 2.10±0.24 (mm3N-1m-1)x10-9 with the addition of 0.5 wt.% La2O3. Furthermore, grain sizes decreased and microhardness values increased with increasing mechanical alloying duration.
1H NMR Study of Hydrogen Site Occupancy in Hydrides of Disordered Ti-V and Ti-V-Cr Alloys
Authors: Kurenkova Elena , Vyvodtseva Anna , Shelyapina Marina G. , Chizhik Vladimir I. , Ievlev Alexandr V. , Skryabina N.E. , Aleksanyan Anahit G. , Fruchart Daniel
Published: November 2012

According to 1H NMR study in fcc hydrides of disordered Ti-V alloys hydrogen atoms are distributed over both octahedral and tetrahedral sites. The occupancy of octahedral sites increases with the vanadium concentration. In hydrides of ternary Ti-V-Cr alloys hydrogen atoms occupy tetrahedral sites only.
Rethinking poverty, power and privilege: A feminist post-structuralist research exploration
Authors: Hulme Thérèse
Published: November 2012

In this article, I described how the use of feminist methodology and post-structuralist analyses of the experiences of women in a poor ‘Coloured’ community in my research led to new understandings of the experiences of poverty and privilege. I discovered the relevance of Foucault’s historical analysis of the operation of ‘pastoral power’ through the narratives of women from the Scottsville community. Historical and current accounts of so-called ‘Coloured’ women’s subjugation and categorisation are reminders of how it came about that ‘being Coloured’ became associated in South Africa with shame and with ‘knowing one’s place’. Feminist post-structuralist analyses made visible the conditions that created practices of injustice in poor women’s lives whilst, at the same time, creating conditions of privilege for me. Justice-making in Scottsville therefore started with a radical rethinking of the terms by which people’s marginalisation took place and, consequently also of the terms of ‘just’ cross-cultural engagements.
Pastorale begeleiding van die self-mutileerder
Authors: Coetzer Wentzel C.
Published: November 2012

In hierdie artikel het  dit geblyk dat die toenemende voorkoms van self-mutilering onder jongmense in talle gevalle as uitlaatklep gedien het vir opgeboude druk en nie soseer as ‘n selfmoordpoging nie. Heel dikwels was dit ‘n uitvloeisel van mishandeling en/of seksuele misbruik en die persoon het  dan hierdie metode gebruik om van innerlike pyn ontslae te raak. Gevoelens van alleenheid, ‘n behoefte aan beheer, ‘n behoefte om net íéts te voel, asook ‘n behoefte om die self te straf, kon ook ‘n rol gespeel het. Die gesinsklimaat was oor die algemeen van besondere belang. Hierdie probleem het aan pastorale beraders en aan die kerk ‘n besondere uitdaging gebied deur onder andere veel meer op die probleem van pyn, asook die hantering daarvan te fokus. Dit het  verband gehou met die feit dat ontkenning in die verlede ‘n groot rol gespeel het in sekere kerklike kringe en ook binne sekere gesinne. As deel van ‘n pastoraal-terapeutiese strategie in die begeleiding van die self-mutileerder kon aspekte soos die identifisering van die rol van  leuens, die benutting van oplossings uit die verlede, vergifnis, nagmaal, gebed en meditasie gevolglik uiters belangrike komponente van die helingsproses gevorm het. Pastorale beraders sal hulleself ten volle op die hoogte moet bring van die verskynsel van self-mutilering ten einde in staat te wees om werklik te kan help.Pastoral guidance for the self-mutilator. In this article it seemed that the increase in the occurrence of self-mutilation among young people in many cases served as a pressure-relief valve and not a suicide attempt as such.  It was very often the outcome of ill-treatment and/or sexual abuse and the person used this method to get rid of the inner pain. Feelings of aloneness, a need to be in control, a need to feel at least something and a need to punish the self could also have played a role. The family climate was generally very important. This provided a special challenge for pastoral counsellors as well as the church by, among others, focussing more on the problem of pain and how to handle it. This was relevant to the fact that denial had played a significant role in certain church circles as well as within some families. As part of the pastoral-therapeutic strategy in helping the self-mutilator, aspects such as identifying the role of lies, the use of solutions from the past, forgiveness, the Lord’s Supper, prayer, and meditation were therefore very important components in the healing process. Pastoral counsellors would have to be well informed about the phenomenon of self-mutilation in order to be able to be of real help.
Reliability of Broadrick Flag in Determination of Curve of Spee in Indian Population
Authors: Kashinatha HM , Bembalgi Mahanthesh S , Kumar PC Ramesh , Yarlagadda Kiran Babu , Ateeq P Mohammed
Published: November 2012

Introduction

Occlusion and occlusal plane is the primary criteria in fabrication of posterior restorations. The simplest method of establishment of occlusal plane is through the use of Broadrick occlusal plane analyzer.

Aims

This study aims to know the reliability of Broadrick flag in determination of curve of Spee with different proposed radii in different skeletal relation in Indian population.

Materials and methods

Male and female dentulous subjects were selected randomly. Maxillary and mandibular full arch impressions were made; casts were prepared and mounted in semiadjustable articulator using face bow transfer. Broadrick occlusal plane analyzer was mounted on upper member of articulator. Analysis was done using the proposed radii of curvature. The same procedure was repeated by taking different radii with variations of ¼ inch, difference was measured by metal caliper, tabulated and subjected to statistical analysis.

Results

Results showed that Indian subjects show minor variations in radii, but most of the subjects confirmed the radii, which was proposed by the Lynch CD and McConnell RJ.

Conclusion

Statistical analysis confirmed that proposed radii confirms to existing occlusal plane for different skeletal relationships. Broadrick occlusal plane analyzer is a reliable tool with the proposed radii for Indian population.

How to cite this article

Jagadeesh KN, Kashinatha HM, Bembalgi MS, Ramesh Kumar PC, Yarlagadda KB, Ateeq PM. Reliability of Broadrick Flag in Determination of Curve of Spee in Indian Population. J Contemp Dent Pract 2012;13(5):627-631.
Comparison of Shear Bond Strength of Hydrophilic Bonding Materials: An in vitro Study
Authors: Nirupama C , Kavitha Sarasa , Jacob Josy , Balaji K , Srinivasan B , Murugesan Ramakrishnan , Krishnaswamy NR
Published: November 2012

Aim

The aim of this study was to evaluate and compare the shear bond strength of hydrophilic materials like Transbond MIP with Assure-fluoride releasing light cure sealant paste system (Reliance orthodontic product), Enhance Lc-adhesion booster (Reliance Orthodontics) Prime and Bond NT–one step adhesive with nanotechnology (Dentsply Product India) with Transbond XT as the control group.

Materials and methods

The study was conducted on 180 extracted human premolar teeth which were divided into five main groups. Each group contained 36 teeth, which were further subdivided into three subgroups containing 12 teeth. The teeth were bonded in three different surface environments namely dry, contaminated with artificial saliva and reprimed after contamination with artificial salvia. The brackets were bonded and cured. The shear bond strength was tested using Instron universal testing machine (4501).

Results

The results were subjected to statistical analysis like 3 factorial ANOVA and compared to post-hoc using the Student Newman levels test. The residual resin on the tooth surface after debonding was evaluated with adhesive remnant index.

Clinical significance

The results revealed that in situations in which moisture contamination is critical there is distinct advantage in using hydrophilic primers.

How to cite this article

Nirupama C, Kavitha S, Jacob J, Balaji K, Srinivasan B, Murugesan R, Krishnaswamy NR. Comparison of Shear Bond Strength of Hydrophilic Bonding Materials: An in vitro Study. J Contemp Dent Pract 2012;13(5): 637-643.
Effect of Salivary Contamination on the Bond Strength of Total-etch and Self-etch Adhesive Systems: An in vitro Study
Authors: Ranganath LM , Rajesh AG , Justin Robert M , Paranthaman Hemalatha , Varghese Ranjith P
Published: November 2012

Aim

To evaluate the influence of salivary contamination during dentin bonding procedures on shear bond strength and to investigate the effect of contaminant-removing treatments on the recovery of bond strength for two dentin-bonding agents.

Materials and methods

Seventy-seven human maxillary and mandibular molars were randomly divided into two groups for total-etch adhesive (Single bond-3M ESPE, USA) and self-etch primer (UniFil Bond-GC, Tokyo, Japan) and subjected to contamination with saliva.

The data for each group were subjected to one-way analysis of variance (ANOVA) followed by the Student Newman-Keuls test to make comparisons among the groups (p < 0.05).

Results

Salivary contamination had less adverse effect on the shear bond strength of single bond total-etch adhesive when it was blot dried or washed. UniFil bond was tolerant of salivary contamination, except when contamination occurred after application of the primer.

Conclusion

In single bond adhesive, when the etched surface is contaminated by saliva, blotting the surface and applying the primer can recover the bond strength. Complete drying of the salivary contaminated surface should be avoided. In the UniFil bond groups, the repriming treatment (UF-V and UF-VI) resulted in the recovery of shear bond strength in the specimens contaminated after priming.

Clinical significance

The results of this study showed that total- etch adhesive (single bond) was not affected by salivary contamination on the etched surface when the bonding surface was kept moist. Self-etch adhesive (UniFil bond) also tolerated salivary contamination except when the contamination occurred after application of the primer.

How to cite this article

Justin RM, Paranthaman H, Rajesh AG, Varghese RP, Ranganath LM. Effect of Salivary Contamination on the Bond Strength of Total-etch and Selfetch Adhesive Systems: An in vitro Study. J Contemp Dent Pract 2012;13(5):655-660.
Comparative Evaluation of Oxygen Saturation Levels using Pulse Oxymeter during Nonsurgical and Surgical Periodontal Therapy in Chronic Periodontitis Patients
Authors: Padma R , Goel Saakshi , Shriniwas M , Shreedhara Annaji , Malagi Sachin , Radhika B , Pai BS Jagadish
Published: November 2012

Background and aim

Monitoring is the global method of observation and data recording in relation to body organ and system function that afford constant information to ensure continuous evalutation of the patient's physical condition. Basic monitoring provides essential information for assessing the vital signs, both circulatory and respiratory, and fundamentally comprises the control of blood pressure (BP) and heart rate (HR) and rhythm. Pulse oxymetry is used to record HR and oxygen saturation. The objective of the study was to assess and compare hemodynamic changes by monitoring oxygen saturation level changes during periodontal surgical and nonsurgical therapy.

Materials and methods

A cross-sectional observational study was conducted in 30 chronic periodontitis patients. Patients were divided into two groups; Group A consisted of 15 patients undergoing surgical periodontal therapy, Group B consisted of 15 patients undergoing nonsurgical periodontal therapy. The hemodynamic changes were evaluated by monitoring HR and oxygen saturation level using pulse oxymeter (SaO2). HR and SaO2 were monitored continuously and registered pre-operatively, i.e. 10 minutes before the procedure, intra-operatively and postoperatively, i.e. 10 minutes after the procedure. One-way analysis of variance test (ANOVA) was performed for data analysis.

Results

Both the groups showed a slight fall in oxygen saturation levels intraoperatively, but within the normal range. More decrease in oxygen saturation levels was observed in nonsurgical periodontal therapy as compared to surgical periodontal therapy at intraoperative levels. The differences in the values were statistically significant. There was no statistical difference seen in the postoperative and preoperative values.

Conclusion

Most of the hemodynamic changes induced during the periodontal therapy were within normal limits, taking into consideration the anxiety and stress produced by the surgical intervention. The hemodynamic change was more in nonsurgical as compared to surgical periodontal therapy.

How to cite this article

Padma R, Goel S, Shrinivas M, Shreedhara A, Malagi S, Radhika B, Pai BSJ. Comparative Evaluation of Oxygen Saturation Levels using Pulse Oxymeter during Nonsurgical and Surgical Periodontal Therapy in Chronic Periodontitis Patients. J Contemp Dent Pract 2012;13(5): 661-664.
Analysis of Tumor Marker CA 125 in Saliva of Normal and Oral Squamous Cell Carcinoma Patients: A Comparative Study
Authors: Balan Jude J , Premalatha BR
Published: November 2012

Background

The mortality and morbidity associated with oral squamous cell carcinoma (OSCC) can be greatly reduced if tumor markers which can detect OSCC at an early stage are available. The use of saliva as an alternative to blood could provide a substantial advantage in sampling convenience. Cancer antigen 125 (CA 125) is a tumor-associated antigen found to be increased in epithelial tumors like oral, breast and ovarian cancers.

Aim

To determine whether salivary CA 125 levels are increased significantly in OSCC patients than the control group.

Materials and methods

Sixty OSCC patients and 60 healthy controls were taken for the study. Saliva samples from both the groups were collected, centrifuged and supernatant fluid were subjected to ELISA for assessment of CA 125. The mean salivary CA 125 values of OSCC patients and control group were statistically analyzed using Mann-Whitney U-test.

Results

The mean salivary CA 125 concentration of OSCC group was 320.25 and that of control group was 33.14. Thus, CA 125 was found to be significantly increased in the saliva of OSCC patients than the control group (p < 0.001). Also, there was significant increase in the CA 125 levels as the stage of OSCC increased.

Conclusion

The convenience, reliability and noninvasive nature of salivary CA 125 testing makes it a feasible adjunctive diagnostic tool for detection of OSCC.

How to cite this article

Balan JJ, Rao RS, Premalatha BR, Patil S. Analysis of Tumor Marker CA 125 in Saliva of Normal and Oral Squamous Cell Carcinoma Patients: A Comparative Study. J Contemp Dent Pract 2012;13(5):671-675.
Influence of Maternal Periodontal Disease as a Risk Factor for Low Birth Weight Infants in Indian Population
Authors: Chakki B Arun Kumar , Hunsingi Prahalad , Kumar Anoop , Manidanappanavar Prasanna
Published: November 2012

Background

Low birth weight is a known problem worldwide and appears to be more pronounced in developing countries. In view of the implication of periodontal infection as one of the risk factors for low birth weight and considering the fact that in India only very few studies are conducted in this regard, the present study was conducted to determine whether maternal periodontal disease can act as a risk factor for low birth weight babies.

Materials and methods

The study group consisted of 62 primiparie mothers including 12 low birth weight cases who satisfied the inclusion/exclusion criteria. The age of the patients ranged from 18 to 37 years with a mean age of 23.27 years. Birth weight of the babies ranged from 1.64 to 3.75 kg and the mean weight was 2.67 Kg. Mean weight, height and body mass index (BMI) of the mothers were 53.47 Kg, 1.51 m, 23.48 respectively.

Results

Birth weight of the babies was regressed against age, BMI, plaque index (PI) and community periodontal index (CPI). Periodontitis was significantly associated (p < 0.0005) with a decrease of birth weight.

Conclusion

Periodontal disease was significantly related to preterm low birth weight.

How to cite this article

Chakki BAK, Ealla KR, Hunsingi P, Kumar A, Manidanappanavar P. Influence of Maternal Periodontal Disease as a Risk Factor for Low Birth Weight Infants in Indian Population. J Contemp Dent Pract 2012;13(5):676-680.
Integrating population dynamics into mapping human exposure to seismic hazard
Authors: Freire S. , Aubrecht C.
Published: November 2012

Abstract. Disaster risk is not fully characterized without taking into account vulnerability and population exposure. Assessment of earthquake risk in urban areas would benefit from considering the variation of population distribution at more detailed spatial and temporal scales, and from a more explicit integration of this improved demographic data with existing seismic hazard maps. In the present work, "intelligent" dasymetric mapping is used to model population dynamics at high spatial resolution in order to benefit the analysis of spatio-temporal exposure to earthquake hazard in a metropolitan area. These night- and daytime-specific population densities are then classified and combined with seismic intensity levels to derive new spatially-explicit four-class-composite maps of human exposure. The presented approach enables a more thorough assessment of population exposure to earthquake hazard. Results show that there are significantly more people potentially at risk in the daytime period, demonstrating the shifting nature of population exposure in the daily cycle and the need to move beyond conventional residence-based demographic data sources to improve risk analyses. The proposed fine-scale maps of human exposure to seismic intensity are mainly aimed at benefiting visualization and communication of earthquake risk, but can be valuable in all phases of the disaster management process where knowledge of population densities is relevant for decision-making.
The Toxic Effects of Polychemotherapy onto the Liver Are Accelerated by the Upregulated MDR of Lymphosarcoma
Authors: Sen'kova Alexandra V. , Mironova Nadezhda L. , Patutina Olga A. , Ageeva Tatyana A. , Zenkova Marina A.
Published: November 2012

Antitumor therapy of hematological malignancies is impeded due to the high toxicity of polychemotherapy toward liver and increasing multiple drug resistance (MDR) of tumor cells under the pressure of polychemotherapy. These two problems can augment each other and significantly reduce the efficiency of antineoplastic therapy. We studied the combined effect of polychemotherapy and upregulated MDR of lymphosarcoma RLS40 onto the liver of experimental mice using two treatment schemes. Scheme 1 is artificial: the tumor was subjected to four courses of polychemotherapy while the liver of the tumor-bearing mice was exposed to only one. This was achieved by threefold tumor retransplantation taken from animals subjected to chemotherapy into intact animals. Scheme 2 displays “real-life” status of patients with MDR malignancies: both the tumor and the liver of tumor-bearing mice were subjected to three sequential courses of polychemotherapy. Our data show that the strengthening of MDR phenotype of RLS40 under polychemotherapy and toxic pressure of polychemotherapy itself has a synergistic damaging effect on the liver that is expressed in the accumulation of destructive changes in the liver tissue, the reduction of the regeneration capacity of the liver, and increasing of Pgp expression on the surface of hepatocytes.
Immune Recognition of Heat Shock Proteins Provides a Molecular Basis for the “Hygiene Hypothesis” Linking High Prevalence of Immune Disorders to Lack of Cell Stress Eliciting Events
Authors: van Eden W.
Published: November 2012

A modern interpretation of the hygiene hypothesis proposes the so-called “old friends” to trigger tolerogenic responses through innate receptors of dendritic cells (DC). Tolerogenic DCs would drive regulatory T-cell polarization through induction of old-friend-specific Treg. In the tissues of the gut that are besieged by our old friends, these cells are held to produce a continuous bystander regulation. However, such local bystander regulation in the gut may be difficult to reconcile with suppression of responses to airway allergens or autoimmune antigens present in distant body tissues. Alternatively, the regulatory Tregs may be triggered through recognition of stress proteins or heat shock proteins (HSP). Microbial HSP are immunodominant and evolutionary conserved with homologs present in mammalian cells. Microbial HSP are now known to induce Tregs that cross-recognize mammalian HSP. In addition, microbial exposures, both friendly and nonfriendly, cause cell stress and, consequently, HSP upregulation in host cells. Also such upregulated HSP can activate HSP-specific Tregs that target the upregulated HSP at sites of inflammatory stress wherever in our body. Under inflammatory conditions, cell stress-associated HSP are abundant and therefore easy targets for cognate T-cell interactions. Herewith, they provide a molecular basis for the hygiene hypothesis.
Endothelial Nitric Oxide Synthase (NOS3) +894 G>T Associates with Physical Activity and Muscle Performance among Young Adults
Authors: Guidry Margaux A. , Kostek Matthew A. , Angelopoulos Theodore J. , Clarkson Priscilla M. , Gordon Paul M. , Moyna Niall M. , Visich Paul S. , Zoeller Robert F. , Thompson Paul D. , Devaney Joseph M. , Gordish-Dressman Heather , Hoffman Eric P. , Pescatello Linda S.
Published: November 2012

Objective. We examined the influence of missense polymorphism, endothelial nitric oxide synthase (NOS3) +894 G>T (rs1799983), on habitual physical activity (PA) and the muscle strength response to resistance training (RT). Methods. Men (n=354) and women (n=424; 24.3±8.0 yr) were genotyped. Subjects reported hr/wk in vigorous and light intensity PA and sitting on the Paffenbarger PA questionnaire. One repetition maximum assessed muscle strength. Multivariable and repeated measures ANCOVA tested differences among NOS3 +894 G>T and PA and RT phenotypes by gender. Results. hr/wk in vigorous intensity PA (5.4±1.2 versus 8.3±0.4; P=0.019), more hr/wk in light intensity PA (42.1±2.4 versus 35.8±0.7; P=0.011), and less hr/wk sitting (37.6±2.8 versus 45.8±0.9; P=0.006) than those with the G allele. Women with NOS3 +894 TT gained more absolute (4.4±0.3 versus 3.7±0.8 kg; P=0.013) and relative (78.3±5.8 versus 61.9±1.8%; P=0.007) strength than those with the G allele. Conclusions. NOS3 +894 G>T associated with PA among men and women and the muscle strength response to RT among women only. Our findings indicate the need for prospective studies examining the influence of NOS3 variants on PA and the muscle response to RT as well as elucidating underlying mechanistic pathways for the associations observed.
Collision-Detecting Device for Omnidirectional Electric Wheelchair
Authors: Ishida Shuichi , Miyamoto Hiroyuki
Published: November 2012

An electric wheelchair is the device to support the self-movement of the elderly and people with physical disabilities. In this paper, a prototype design of an electric wheelchair with a high level of mobility and safety is presented. The electric wheelchair has a high level of mobility by employing an omnidirectional mechanism. Large numbers of mechanisms have been developed to realize omnidirectional motion. However, they have various drawbacks such as a complicated mechanism and difficulty of employment for practical use. Although the ball wheel drive mechanism is simple, it realizes stable motion when negotiating a step, gap, or slope. The high level of mobility enhances the freedom of users while increasing the risk of collision with obstacles or walls. To prevent collisions with obstacles, some electric wheelchairs are equipped with infrared sensors, ultrasonic sensors, laser range finders, or machine vision. However, since these devices are expensive, it will be difficult for them to be widely used with electric wheelchairs. We have developed a prototype design of collision-detecting device with inexpensive sensors. This device detects the occurrence of collisions and can calculate the direction of the colliding object. A prototype has been developed to perform motion experiments and verify the accuracy of the device. The results of experiments are also presented in this paper.
Effects of a UV-absorbing greenhouse covering film on tomato yield and quality
Authors: Papaioannou Ch. , Katsoulas N. , Maletsika P. , Siomos A. , Kittas C.
Published: November 2012

The effect of blocking the ultraviolet (UV) solar radiation using a UV-absorbing low density polyethylene (PE) film on tomato crop yield and fruit quality was evaluated in a two-year study in two arched roof greenhouses located in Central Greece. The UV-A and UV-B radiation transmission values of the greenhouse covered by the UV-absorbing PE film during the first year were 0.4% and 1.2%, respectively and increased to 0.8% and 1.3% in the 2nd year, while the respective values in the greenhouse covered by a traditional PE film were 20.7% and 12.5% during the 1st year and 28.7% and 26.7% during the 2nd year. Under the UV-absorbing film the number of insect injured fruit was reduced and the marketable yield was similar or higher than that under the common PE film, while fruit quality characteristics (size, shape), nutritional value (ascorbic acid and lycopene) and organoleptic quality (pH, titratable acidity and total soluble solids) were similar under both covering materials. Moreover, the reduction of incoming UV radiation had an appreciable effect on fruit skin color, indicating an effect on pigments other than lycopene.
Saline reclaimed wastewater can be used to produce potted weeping fig (Ficus benjamina L.) with minimal effects on plant quality
Authors: Valdés R. , Miralles J. , Ochoa J. , Sánchez-Blanco M. J. , Bañón Arias S.
Published: November 2012

The objective of the present study was to investigate the limitations of irrigation with saline reclaimed wastewater (RW) for producing potted weeping fig (Ficus benjamina L.). Furthermore, two different levels of leaching were studied to ascertain whether either reduces the negative effects of RW. Three irrigation treatments were applied: a) well water (control), b) RW (5 dS m-1) with a constant leaching fraction of 23% (RWL), and c) RW (5 dS m-1) with a constant leaching fraction of 15% and 50% flushing every nine irrigation events (RWF). After five months of exposure to the RW, plant size, leaf area, specific leaf area, plant DW, stem diameter and shoot/root ratio were reduced, but both compactness and the appearance of the plants remained high. RWF reduced leaf area, plant dry weight, stem diameter, leaf lightness, leaf chroma and leaf SPAD compared with the RWL. Water consumption per pot was higher in control (50.58 L), followed by RWL (24.29 L) and RWF (19.6 L). Photosynthesis and stomatal conductance were 50% lower in RWL plants than in the control, while the RWF plants had the lowest rates. RWF caused damages in the photochemical apparatus. This study confirms that: a) weeping fig is a good candidate for being grown with saline RW without compromising its aesthetic value; b) RW may be regarded as a good alternative to the retardants used in this plant; and c) the recommended irrigation would be RWL.
Post-market environmental monitoring of Bt maize in Spain: Non-target effects of varieties derived from the event MON810 on predatory fauna
Authors: Albajes R. , Farinós G. P. , Perez-Hedo M. , De la Poza M. , Lumbierres B. , Ortego F. , Pons X. , Castañera P.
Published: November 2012

The Spanish Government has established post-market environmental monitoring (PMEM) as mandatory for genetically modified (GM) crop varieties cultivated in Spain. In order to comply with this regulation, effects of Bt maize varieties derived from the event MON810 on the predatory fauna were monitored for two years in northeast and central Spain. The study was carried out with a randomized block design in maize fields of 3-4 ha on which the abundance of plant-dwelling predators and the activity-density of soil-dwelling predators in Bt vs. non-Bt near-isogenic varieties were compared. To this end, the plots were sampled by visual inspection of a certain number of plants and pitfall traps 6 or 7 times throughout two seasons. No significant differences in predator densities on plants were found between Bt and non-Bt varieties. In the pitfall traps, significant differences between the two types of maize were found only in Staphylinidae, in which trap catches in non-Bt maize were higher than in Bt maize in central Spain. Based on the statistical power of the assays, surrogate arthropods for PMEM purposes are proposed; Orius spp. and Araneae for visual sampling and Carabidae, Araneae, and Staphylinidae for pitfall trapping. The other predator groups recorded in the study, Nabis sp. and Coccinellidae in visual sampling and Dermaptera in pitfall trapping, gave very poor power results. To help to establish a standardized protocol for PMEM of genetically modified crops, the effect-detecting capacity with a power of 0.8 of each predator group is given.
DFT and MP2 Study of the Molecular Structure and Vibrational Spectra of the Anticancer Agent Cyclophosphamide
Authors: Badawi Hassan M. , Förner Wolfgang
Published: November 2012

The possible conformations in the most stable structure of cyclophosphamide were investigated at the DFT-B3LYP and MP2/6-311G** levels of calculation. The axial structure is calculated to be lower in energy than the equatorial form of cyclophosphamide by 5 (MP2) to 6 (DFT) kcal mol-1 because of a very weak anomeric effect and weak conjugation. Further it is the same structure as the one found in the X-ray investigations both of the hydrate and of the anhydrous form. The computed DFT vibrational frequencies of the axial structure were used to analyze the infrared and Raman spectra using normal-coordinate calculations to provide reliable assignments to the normal modes of the molecule.