The title complex, dichlorido[N,N-di-methyl-2-(η(5)-tetra-methyl-cyclo-penta-dien-yl)acetamidinido-κN']titanium(IV), [Ti(C(13)H(20)N(2))Cl(2)], exhibits an unusual ansa-bridged conformation. The cyclo-penta-dienyl ring and the mean plane of the Ti-N=C-C-C fragment form a dihedral angle of 88.08 (11)°.

Dental erosion develops through chronic exposure to extrinsic/intrinsic acids with a low pH. Enamel erosion is characterized by a centripetal dissolution leaving a small demineralized zone behind. In contrast, erosive demineralization in dentin is more complex as the acid-induced mineral dissolution leads to the exposure of collagenous organic matrix, which hampers ion diffusion and, thus, redu...

Objective: To explore the changes in nickel-titanium (NiTi) archwires after exposure to fluoride-containing acetic acid solutions. Materials and methods: Preformed rectangular NiTi wires were immersed in either an acidulated fluoride solution, a neutral fluoride solution or distilled water (control) for 1.5 hours at 37°C. After immersion, the unloading force values at four deflection points wer...

The purpose of this study was the dosimetric evaluation of thermoluminescent detectors of calcium sulphate doped with dysprosium (CaSO4:Dy) produced by IPEN compared to the TL response of lithium fluoride doped with magnesium and titanium (LiF:Mg,Ti) dosimeters and microdosimeters produced by Harshaw Chemical Company to clinical photon beams dosimetry (6 and 15 MV) using liquid water and PMMA p...

OBJECTIVE (1) To evaluate the corrosion resistance of four different orthodontic archwires and to determine the effect of 0.5% NaF (simulating high fluoride-containing toothpaste of about 2250 ppm) on corrosion resistance of these archwires. (2) To assess whether surface roughness (Ra) is the primary factor influencing the corrosion resistance of these archwires. MATERIALS AND METHODS Four di...

This book chapter presents a brief description of a new emerging field of science, the biological surface science and stresses its importance in the field of alloplastic materials and dental implants. It is not intended to present a comprehensive review of the field, but rather to indentify some important trends and directions in the surface modifications of titanium (Ti) dental implants target...

Spark discharge anodic oxidation forms porous TiO2 films on titanium implant surfaces. This increases surface roughness and concentration of calcium and phosphate ions and may enhance early osseointegration. To test this, forty 3.75 mm × 13 mm titanium implants (Megagen, Korea) were placed into healed mandibular postextraction ridges of 10 sheep. There were 10 implants per group: RBM surface (c...

The susceptibility to hydrogen absorption and hydrogen thermal desorption of titanium alloys has been investigated in a neutral 2.0% NaF solution at 37 C under various applied cathodic potentials. Ti-0.2Pd, Ti-6Al-4V and Ti-11.3Mo-6.6Zr-4.3Sn alloys absorb hydrogen under less noble potentials than 1:5V, 1:9V and 1:4V versus a saturated calomel electrode, respectively. The amounts of absorbed hy...

The purpose of this study was to investigate the effects of topical fluoride prophylactic agents on the mechanical unloading properties of nickel-titanium (NiTi) and stainless steel (SS) closed coil springs. Spring were stored at 37 ̊C under static load in phosphate buffered saline (PBS) and treated with either neutral sodium fluoride (NaF) or acidulated phosphate fluoride (APF) five days per we...