Adhesive Restorations and the Oral Environmental Behaviour

Adhesive restorations are based on the use of materials, which have the capacity to bond tooth effectively. This is possible due to a polymerizing hybrid layer interface created by the use of the Etch&Rinse (ERAs) and self-etching adhesives (SEAs). Bonding using ERAs include the acid-etching removal of the mineral phase from the substrates of enamel and dentine. A hybrid layer results by filling the voids left by minerals by means of adhesive monomers. However, etching dentine may result in too much demineralization and wetness with discrepancies in reinforcement at the bottom of hybrid layer. SEAs avoid the separate etching phase of ERAs using acidic functional monomers. In the two-step SEAs, hybridization is created by the application of a primer of different pH acidity, followed by an adhesive resin. In the ‘One-Step SEAs’, acidic and adhesive monomers are mixed in the same bottle thereby causing hybridization at the same time. 10-MDP mild SEAs represent the better bonding technology in dentistry due to the ability to form a strong chemical bond in tooth tissue. However, adhesive restorations have high vulnerability in the oral environment, which have been attributed to the esterase activity of Streptococcus mutans and hydrolysis by matrix metalloproteinase

Methamphetamine abuse and “meth mouth” in Europe

With easy chemical synthesis from its precursor, methamphetamine (MA) is now widespread in many countries. The abuse of methamphetamine is associated with several negative effects on health, because MA is a neurotoxin and a dangerous central nervous system stimulant. It changes levels of neurotransmitters in the brain, releasing dopamine and inhibiting nor epinephrine uptake which increases sympathetic nervous system activity and can lead to cardiac arrhythmia, hypertension and tachypnea. The consequences of MA abuse are clearly manifested in oral diseases (like “meth mouth”) which is characterised by extensive caries, teeth grinding with ensuing dental wear and trismus. The present review was designed to fill the gap in knowledge about methamphetamine abuse in the European Union (EU) and to illustrate the main clinical effects of prolonged use. After describing the pharmacology and systemic effects of methamphetamine and concentrating on its effects on the mouth, the present review compares the epidemiology and incidence of abuse in the world, particularly the USA and the EU

Very late but too early... prof. Angelo Chiavaro and the Italian degree in dentistry

La nascita della Laurea in Odontoiatria in Italia è stata molto contrastata e solo nel 1980 ha visto la sua effettiva realizzazione. Molto ”istruttiva” al riguardo è la vicenda relativa all’istituzione nel 1924, periodo della presa di potere da parte del Fascismo, di una “Scuola Nazionale di Odontoiatria” presso l’Università di Roma, revocata appena dieci mesi dopo. Il maggiore sostenitore e propugnatore della Scuola, il prof. Angelo Chiavaro, venne dopo qualche anno “punito” con il trasferimento d’ufficio dall’Università di Roma a quella di Genova. Presentiamo alcune brevi note relative alla biografia di questo coraggioso precursore e alla vicenda di cui fu protagonista.The birth of the Degree in Dentistry in Italy has been very troubled, and only in 1980 saw its effective implementation. Very “instructive” in this regard is the history on the establishment in 1924 (the period of the seizure of power by Fascism) of a “National School of Dentistry” at the University of Rome, which was withdrawn after only ten months. The biggest supporter and proponent of the School, Prof. Angelo Chiavaro, after a few years, was “punished” with the transfer from the University of Rome to that of Genoa. We present some brief notes on the biography of this courageous pioneer and the matter of which he was the protagonist

Very late but too early... prof. Angelo Chiavaro and the Italian degree in dentistry

La nascita della Laurea in Odontoiatria in Italia è stata molto contrastata e solo nel 1980 ha visto la sua effettiva realizzazione. Molto ”istruttiva” al riguardo è la vicenda relativa all’istituzione nel 1924, periodo della presa di potere da parte del Fascismo, di una “Scuola Nazionale di Odontoiatria” presso l’Università di Roma, revocata appena dieci mesi dopo. Il maggiore sostenitore e propugnatore della Scuola, il prof. Angelo Chiavaro, venne dopo qualche anno “punito” con il trasferimento d’ufficio dall’Università di Roma a quella di Genova. Presentiamo alcune brevi note relative alla biografia di questo coraggioso precursore e alla vicenda di cui fu protagonista.The birth of the Degree in Dentistry in Italy has been very troubled, and only in 1980 saw its effective implementation. Very “instructive” in this regard is the history on the establishment in 1924 (the period of the seizure of power by Fascism) of a “National School of Dentistry” at the University of Rome, which was withdrawn after only ten months. The biggest supporter and proponent of the School, Prof. Angelo Chiavaro, after a few years, was “punished” with the transfer from the University of Rome to that of Genoa. We present some brief notes on the biography of this courageous pioneer and the matter of which he was the protagonist

Molto tardi ma troppo presto… il prof. Angelo Chiavaro e la laurea in odontoiatria italiana

La nascita della Laurea in Odontoiatria in Italia è stata molto contrastata e solo nel 1980 ha visto la sua effettiva realizzazione. Molto "istruttiva" al riguardo è la vicenda relativa all'istituzione nel 1924, periodo della presa di potere da parte del Fascismo, di una "Scuola Nazionale di Odontoiatria" presso l'Università di Roma, revocata appena dieci mesi dopo. Il maggiore sostenitore e propugnatore della Scuola, il prof. Angelo Chiavaro, venne dopo qualche anno "punito" con il trasferimento d'ufficio dall'Università di Roma a quella di Genova. Presentiamo alcune brevi note relative alla biografia di questo coraggioso precursore e alla vicenda di cui fu protagonista.Ključne riječ

High resolution spectroscopy in the XUV with pairs of mutually coherent and time-delayed laser harmonics

We present a Ramsey technique using high-order harmonics for high-resolution atomic spectroscopy in the extreme ultraviolet. Pairs of time-delayed and phase-coherent harmonic pulses generated by the interaction of ultrashort and intense laser pulses with a noble gas are used to study excited states of krypton

Scanning electron microscopic analysis of the efficacy of acid etching on cat enamel

The effect of etching on cat enamel made with 40% orthophosphoric acid for different times was evaluated. Twenty-one cat teeth were selected and randomly divided into three groups of seven teeth each. They were subjected to etching on a circular area of the coronal enamel (diameter = 2 mm) for 30 s (group A), 45 s (group B) and 60 s (group C). The samples obtained were observed by a scanning electron microscope focusing on the border area between etched and unetched enamel, to highlight the differences. The micrographs were subjected to blind assessment of three experienced operators. The groups were statistically assessed with the Wilcoxon test. At 30, 45 and 60 s, the acid attack results only in the formation of an irregular enamel surface and without uncovering and attack of the prismatic organisation. Prismatic areas with preferential interprismatic action could be detected in few samples etched for 60 s. Analysis with ImageJ was also used to quantify the efficacy of acid etching in the conditions used for human enamel, by an evaluation of grey levels. In cat enamel the etching times considered are not as effective as in human enamel for the purpose of adhesion and the presence of a thick prismless layer could explain this result

ARTURO BERETTA AND THE “TROPHOMICROBIC THEORY OF THE CARIES”

Il più originale contributo portato dalla Scuola italiana allo studio della eziopatogenesi della carie è senza dubbio rappresentato dalla “teoria trofomicrobica” elaborata da Arturo Beretta, primo docente ufficiale di Odontoiatria nell’Università di Bologna nel 1918. Nel presente lavoro, dopo aver presentato alcuni cenni biografici e bibliografici sull’Autore (ch fu, tra l’altro Preside della Facoltà Medica di Bologna e giunse ad essere nominato Senatore per chiara fama) vengono illustrati i principi di tale teoria precorritrice basata sulla aggiunta alla teoria chimico-parassitaria di Miller del ruolo della predisposizione dello smalto e della saliva dell’ospite. Viene anche ricordata l’opera dei principali autori italiani e non italiani che hanno utilizzato o modificato l’idea di Beretta.Najizvorniji doprinos talijanske škole istraživanju nastanka karijesa svakako je “trofomikrobijska teorija” Artura Berette, prvog profesora stomatologije na Sveučilištu u Bologni 1918. Ovaj članak sažima biografske i bibliografske zapise o Beretti (koji je, između ostalog, bio i dekan Medicinskog fakulteta u Bologni te član talijanskog Senata), kao i načela njegove teorije, koja se nastavljaju na Millerovu “kemijsko-parazitsku” teoriju o svojstvima cakline i sline domaćina koja pogoduju nastanku karijesa. U članku se spominju i najvažniji radovi talijanskih i drugih znanstvenika koji su prihvatili i dopunili Berettinu zamisao.The most original contribution made by the Italian School to the study of caries aetiology is undoubtedly the “trophomicrobic theory” proposed by Arturo Beretta, the first teacher of dentistry at the University of Bologna in 1918. This article brings biographical and bibliographical notes about Beretta (who was, among other things, Dean of the Faculty of Medicine of Bologna and Senator), and summarises the principles of his theory, which adds to Miller’s “chemical-parasitic” theory of caries-predisposing properties of the enamel and host saliva. It also recalls the work of major Italian and non-Italian researchers who have used or modified Beretta’s idea

Optical delay control of large-spectral-bandwidth laser pulses

In this letter we report the first experimental observation of temporal delay control of large-spectral-bandwidth multimode laser pulses by means of electromagnetically induced transparency (EIT). We achieved controllable retardation with limited temporal distortion of optical pulses with an input spectral bandwidth of 3.3 GHz. The experimental results compare favorably with theoretical predictions.Comment: Submitted to Optics Letters (January 2009