Diamond burs versus curettes in root planing: a randomized clinical trial

Aim: This study compares diamond burs and curettes by clinical, microbiological, biochemical, scanning electron microscopic parameters and treatment time data in the non-surgical periodontal treatment of patients with chronic periodontitis. Methods: Two quadrants of each of the 12 patients received root planing with diamond burs whereas other 2 quadrants were treated with curettes. Clinical periodontal measurements were recorded at baseline and then 1, 3, 6 months after completion of non-surgical periodontal treatment. Subgingival plaque, gingival crevicular fluid samples were obtained at baseline and 1-month control. Twenty-one hopeless teeth received root planing with diamond burs or curettes or no treatment at all and then extracted for microscopic evaluations. Results: Clinical periodontal parameters improved similarly with both treatment modalities. Microbiological analyses revealed similar findings for the bacterial load (16S gene copy numbers), ratio of each bacterium to the total bacterial count at baseline, 1-month control. Cytokine levels in the gingival crevicular fluid samples exhibited differences between the two treatments. Scanning electron microscopic analyses indicated that diamond burs were better in terms of calculus removal, loss of tooth substance indices, but roughness index values were better for curettes. Conclusion: As a conclusion, diamond burs provide findings comparable with curettes in root planing

Crystal structure of 3-(4-chlorophenoxy)-4-(2-nitrophenyl)azetidin-2-one with an unknown solvate

Acknowledgements The authors are indebted to the X-ray laboratory of Dicle University Scientific and Technological Applied and Research Center, Diyarbakir, Turkey, for use of the X-ray diffractometer. AJ and HAS thank the Shiraz University Research Council for financial support.Peer reviewedPublisher PD

1-Methyl-6-nitro-1H-benzimidazole

The title compound, C8H7N3O2, a potential anti­tumour drug and an anti­oxidant agent, was studied in order to give more insight into structure–function relationships. The 1-methyl­benzimidazole unit of the mol­ecule was found to be exactly planar and the nitro group is inclined at an angle of 10.4 (2)° to the plane of the heterocycle. The bond lengths in the present derivative were analyzed in details and compared with those of the parent unsubstituted analogues in the Cambridge Structural Database. The results have shown that the additional nitro group is not involved in conjugation with the adjacent π-system and hence has no effect on the charge distribution of the heterocyclic ring

5-Chloro-4′-ethyl-3H-spiro­[1,3-benzo­thia­zole-2,1′-cyclo­hexa­ne]

In the title compound, C14H18ClNS, the 2,3-dihydro-1,3-thia­zole ring adopts an envelope with the S,N-bound C atom at the flap and the cyclo­hexane ring adopts a chair conformation. In the crystal, N—H⋯S hydrogen bonds with C(5) motifs connect the mol­ecules into chains parallel to the c axis

3-(2,4-Dichloro­phen­oxy)-1-(4-meth­oxy­phen­yl)-4-(3-nitro­phen­yl)azetidin-2-one

In the title compound, C22H16Cl2N2O5, the nearly planar four-membered β-lactam ring [maximum deviations of 0.011 (2) for the N atom] makes dihedral angles of 68.34 (13), 83.04 (13) and 3.37 (13)° with the dichloro-, nitro- and meth­oxy­phenyl rings, respectively. The crystal structure is stabilized by C—H⋯O hydrogen-bond inter­actions. In addition, a π–π stacking inter­action [centroid–centroid distance = 3.6622 (12) Å] is observed between the β-lactam and nitro­phenyl rings

1-(1H-Benzimidazol-1-ylmeth­yl)-3-[2-(di­isopropyl­amino)eth­yl]-1H-benzimid­azolium bromide 0.25-hydrate

The title N-heterocyclic carbene derivative, C23H30N5 +·Br−·0.25H2O, was synthesized using microwave heating and was characterized by 1H and 13C NMR spectroscopy and a single-crystal X-ray diffraction study. The structure of the title compound are stabilized by a network of intra- and inter­molecular C—H⋯Br hydrogen-bonding inter­actions. The crystal structure is further stabilized by π–π stacking inter­actions between benzene and imidazole fragment rings of parallel benzo[d]imidazole rings, with a separation of 3.486 (3) Å between the centroids of the benzene and imidazole rings. There is also an inter­molecular C—H⋯π inter­action in the crystal structure. The C—N bond lengths for the central benzimidazole ring are shorter than the average single C—N bond, thus showing varying degrees of double-bond character and indicating partial electron delocalization within the C—N—C—N—C fragment. The isopropyl group is disordered over two sites with occupancies of 0.792 (10) and 0.208 (10)

Dichloridobis[5-nitro-1-trimethyl­silyl­methyl-1H-benzimidazole-κN 3]cobalt(II) N,N-dimethyl­formamide solvate

The title compound, [CoCl2(C11H15N3O2Si)2]·C3H7NO, was synthesized from 5-nitro-1-trimethyl­silylmethyl-1H-benzimid­azole and cobalt(II) chloride in dimethyl­formamide. The CoII atom is coordinated in a distorted tetra­hedral environment by two Cl atoms and two N atoms. In the crystal structure, there are a number of C—H⋯Cl and C—H⋯O hydrogen-bonding inter­actions between symmetry-related mol­ecules

2-[(E)-(4-Methyl­phen­yl)imino­meth­yl]-6-(morpholin-4-ylmeth­yl)phenol

In the title compound, C19H22N2O2, the morpholine ring adopts an almost perfect normal chair conformation with puckering parameters Q T, θ and ϕ of 0.5642 (18) Å, 177.32 (17) and ϕ = 10 (4)°, respectively. The two benzene rings make a dihedral angle of 42.67 (8)° with each other. An intra­molecular O—H⋯N hydrogen bond helps to stabilize the mol­ecular conformation. Aromatic C—H⋯π inter­actions and π–π stacking inter­actions [centroid–centroid distance = 3.6155 (15) Å] between the benzene rings contribute to the stabilization of the crystal structure