Factorial analysis of variables affecting bone stress adjacent to mini-implants used for molar distalization by direct anchorage-A finite element study.

OBJECTIVE: The aim of this study was to investigate the stresses on mini-implant, cortical bone, and cancellous bone for maxillary molar distalization using an orthodontic implant in a finite element model for different angulations and depths of insertion. METHODS: A three-dimensional finite element method was used to simulate overall orthodontic tooth movements by using ANSYS software. The maxillary bone and the molars were reproduced using CT scan images and conversion of the same into STL file was done. Finite element model was generated and the effect of forces was studied on the model for different depths and angulations of mini-implant insertions. The distalization force was exerted by an open-coil spring and the direct skeletal anchorage was provided by a mini-implant. Mini-implants were placed in depths of 5 mm, 7 mm, and 9 mm inside the bone and insertion angles of 30°, 60°, and 90°. Stresses on mini-implant and extent of stress on the surrounding bone were assessed by the software. RESULTS: 1. Least stress was found when the mini-implant was inserted at an angle of 30°, as it is nearer to the stronger cortical bone. 2. As the length of the mini-implant increases, accompanied by the increase in the depth of insertion, a decrease in stress in the mini-implant, cortical bone, and cancellous bone was noticed. CONCLUSION: An increase in the insertion angle from 30° to 90° increases the stresses on both the implant and the cortical bone. A higher depth of thread in the bone helps in reducing the stress on the implant, cortical bone, and cancellous bone. This helps in improving the primary stability of the mini-implant and its life.

Correction: Elucidation of hydrogen bonding formation by a computational, FT-IR spectroscopic and theoretical study between benzyl alcohol and isomeric cresols.

[This corrects the article DOI: 10.1039/C5RA26298D.].

"Effect of grape seed and green tea on shear bond strength of brackets bonded to bleached enamel with and without Lase Peroxide Lite" - An in vitro study.

OBJECTIVE: To investigate the effect of antioxidants on shear bond strength of brackets bonded to bleached enamel with and without titanium dioxide nanoparticles (Lase Peroxide Lite). MATERIALS AND METHODS: One hundred and five human maxillary premolars were randomly divided into seven groups (n = 15). Group I served as control, in group II-A bleaching was performed with Opalescent Boost. In group II-B and C, bleaching was performed with Opalescent Boost followed by application of 5% grape seed and 10% green tea extracts, respectively. Group III-A bleaching was performed with Lase Peroxide Lite. Group III-B and III-C bleaching was performed with Lase Peroxide Lite followed by application of 5% grape seed and 10% green tea extracts, respectively. Brackets were bonded with composite resin and cured with light emitting diode (LED) light. Shear bond strength of brackets was tested with a Universal testing machine. RESULTS: There was statistically significant difference in the shear bond strength among the seven groups included in the study. There is a statistically significant decrease in shear bond strength in group II-A (8.2 ± 1.6 Mpa), group III-A (8.6 ± 2.1 Mpa) when compared with group I-A (15.9 ± 1.4 Mpa). Among all experimental groups, group II-A showed the lowest mean shear bond-strength values (8.2 ± 1.6 Mpa) (P < 0.005). Group III-C (14.9 ± 2.2 Mpa) has significantly higher shear bond strength. CONCLUSION: Bleaching reduced the shear bond strength of brackets below acceptable level while application of grape seed and green tea extracts has recovered the shear bond strength.

Molecular characterisation of lineage IV peste des petits ruminants virus using multi gene sequence data.

Peste des petits ruminants is responsible for an economically important plague of small ruminants that is endemic across much of the developing world. Here we describe the detection and characterisation of a PPR virus from a recent outbreak in Tamil Nadu, India. We demonstrate the isolation of PPR virus from rectal swab and highlight the potential spread of disease to in-contact animals through faecal materials and use of faecal material as non-invasive method of sampling for susceptible wild ruminants. Finally we have performed a comprehensive 'multi-gene' assessment of lineage IV isolates of PPRV utilising sequence data from our study and publically available partial N, partial F and partial H gene data. We describe the effects of grouping PPRV isolates utilising different gene loci and conclude that the variable part of N gene at C terminus gives the best phylogenetic assessment of PPRV isolates with isolates generally clustering according to geographical isolation. This assessment highlights the importance of careful gene targeting with RT-PCR to enable thorough phylogenetic analysis.

A new cascade reaction: concurrent construction of six and five membered rings leading to novel fused quinazolinones.

A one-pot cascade reaction has been developed leading to the concurrent construction of six and five membered fused N-heterocyclic rings of indazolo[3,2-b]quinazolinones. The methodology involved the reaction of isatoic anhydride, a hydrazine and o-iodo benzaldehyde in the presence of Pd(PPh(3))(4) and BINAP in MeCN. The mechanism of this cascade reaction is discussed. A variety of indazolo[3,2-b]quinazolinone derivatives were prepared by using this methodology in good yields, some of which were tested for their PDE4 inhibitory properties in vitro. The dose response and docking study performed using a representative compound is presented.

N-heterocyclic carbene-mediated hydroacylation-Sonogashira/Heck/Suzuki coupling in a single pot: a new cascade reaction.

A dually NHC-catalyzed reaction cascade comprising an initial hydroacylation of an activated ketone and subsequent Sonogashira/Heck/Suzuki coupling in the same pot is reported. The reaction mechanism and scope of the methodology is presented.

Construction of a six-membered fused N-heterocyclic ring via a new 3-component reaction: synthesis of (pyrazolo)pyrimidines/pyridines.

A conceptually new three-component reaction was developed to construct a six-membered fused N-heterocyclic ring affording (pyrazolo)pyrimidines/pyridines as potential inhibitors of PDE4. The reaction is catalyzed by triflic acid in acetic acid in the presence of aerial oxygen.

Yb(OTf)3 catalyzed new cascade reaction: a facile assembly of fused quinazolinones.

A one-pot Yb(III)-mediated cascade reaction has been developed leading to small molecules based on a novel structural motif, i.e. quinazolin-4-one moiety fused with an isoquinoline ring, for potential inhibition of TNF-α.

A new three-component reaction: green synthesis of novel isoindolo[2,1-a]quinazoline derivatives as potent inhibitors of TNF-α.

Concurrent construction of five and six membered fused N-heretocyclic ring was achieved via a conceptually new three-component reaction affording 6,6a-dihydroisoindolo[2,1-a]quinazoline-5,11-diones as novel inhibitors of TNF-αin vitro. This represents one of the few examples of direct TNF-α inhibition by small molecules.