Peri-implant bone defects: A 1-year follow-up comparative study of use of hyaluronic acid and xenografts.

Objective: The aim of this study was to compare the efficacy of hyaluronic acid (HA) and xenografts on the repair of peri-implant dehiscence-type bone defects occur during implant placement.

Patients And Methods: Forty-two dehiscence Class I type defects located on the buccal surface of the implants were included in this study. Defects were divided into two main groups as small sized (height of <3 mm) and medium sized (height between 3 and 5 mm).

Electrochemical reductive desorption of alkyl self-assembled monolayers studied in situ by spectroscopic ellipsometry: evidence for formation of a low refractive index region after desorption.

Gold-sulphur bonds holding self-assembled monolayers (SAMs) on their gold substrate can be broken by electrochemical reduction, which typically occurs in an electrode potential range where the electrochemical hydrogen evolution reaction (HER) is thermodynamically possible. This work uses an in situ coupling between cyclic voltammetry and spectroscopic ellipsometry to compare the interfacial structure after desorption of the aliphatic thiols 1-Dodecanethiol (DDT) and 1-Octadecanethiol (ODT), and the ω-hydroxythiol 11-Mercapto-1-undecanol (MUD). For MUD and DDT, the data can only be explained by the presence of a substance with a significantly lower refractive index than the aqueous electrolyte in the interfacial region.

Difficulty of impacted mandibular third molar tooth removal: predictive ability of senior surgeons and residents.

Purpose: The present study investigated whether residents are able to estimate the degree of difficulty of mandibular third molar removal to the same extent as senior surgeons.

Materials And Methods: The study included 2 residents and 2 senior surgeons, each of whom extracted 50 mandibular third molars of similar complexity. The clinical variables evaluated included patient age, gender, body size, maximal mouth opening, and tongue interference.

Third-order effects in resonant sum-frequency-generation signals at electrified metal/liquid interfaces.

Vibrational sum-frequency-generation (SFG) spectroscopy experiments at electrified interfaces involve incident laser radiation at frequencies in the IR and near-IR/visible regions as well as a static electric field on the surface. Here we show that mixing the three fields present on the surface can result in third-order effects in resonant SFG signals. This was achieved for closed packed self-assembled monolayers (SAMs) with molecular groups of high optical nonlinearity and surface potentials similar to those typically applied in cyclic voltammograms.

Modulation of electrochemical hydrogen evolution rate by araliphatic thiol monolayers on gold.

Electroreductive desorption of a highly ordered self-assembled monolayer (SAM) formed by the araliphatic thiol (4-(4-(4-pyridyl)phenyl)phenyl)methanethiol leads to a concurrent rapid hydrogen evolution reaction (HER). The desorption process and resulting interfacial structure were investigated by voltammetric techniques, spectroscopic ellipsometry, and vibrational sum-frequency-generation (SFG) spectroscopy. Voltammetric experiments on SAM-modified electrodes exhibit extraordinarily high peak currents, which di er between Au(111) and polycrystalline Au substrates.