Investigating the Mechanisms of Discoloration in Modern Dental Materials: A Comprehensive Characterization Approach.

In general, patients' opinions on reaching ideal esthetics while restoring dental tissues is one of the most important part of the oral treatment. Unfortunately, discoloration of dental materials may occur due to intrinsic and extrinsic factors. The aim of the study was to evaluate the color stability of frequently used dental resin materials and determine the mechanism of their discoloration.

Can glass polyalkenoate (glass-ionomer) dental cements be considered bioactive? A review.

Objectives: This paper reviews the chemical behaviour of glass polyalkenoate (glass-ionomer) dental cements, both conventional and resin-modified, in contact with natural tissues, with the aim of determining whether these materials can be considered to be bioactive.

Data: Relevant papers describing the behaviour of bioactive glasses and ceramics, and glass-ionomer (glass polyalkenoate) cements have been identified using PubMed and Science Direct. This has allowed a comparison to be made between the behaviour of glass-ionomers and the speciality glasses and ceramics that are widely classified as bioactive, a designation considered valid for over fifty years.

Fluoride exchange by glass-ionomer dental cements and its clinical effects: a review.

The topic of fluoride release and uptake by glass-ionomer (glass polyalkenoate) dental cements is reviewed. The study was based on a literature search carried out using PubMed. The main key words used were and , and further refinements were made by adding the keywords , and .

Apical Extrusion of Debris during Root Canal Preparation with ProTaper Next, WaveOne Gold and Twisted Files.

(1) Background: Apical extrusion of debris is an example of a complication that may arise during root canal treatment, and it has been proven to be an unavoidable occurrence during endodontic treatment by numerous authors. Even though it may not hinder the long-term outcome of treatment, it may lead directly to increased levels of postoperative pain and, therefore, lower levels of patient acceptance and satisfaction. The aim of the study was to assess the weight of apically extruded debris during root canal preparation with instruments that use different movement kinematics (rotary, reciprocating, and adaptive motion); (2) Methods: The study was performed using the Myers and Montgomery model.

Surface Studies on Glass Powders Used in Commercial Glass-Ionomer Dental Cements.

The surface properties of three commercial ionomer glass powders, i.e., Fuji IX, Kavitan Plus and Chemadent G-J-W were studied.

Novel nanosystems to enhance biological activity of hydroxyapatite against dental caries.

This work aimed to study for the first time to our knowledge the influence of the structure of the dental flosses (DF) coated by hydroxyapatite nanoparticles (HAP NPs) on the biological performance of saliva probiotic bacteria (S. salivarius), and human dermal and osteoblast-like cells. We used three types of HAP@DF composites (based on two unwaxed dental flosses - "fluffy" and "smooth", and one waxed "smooth") with different morphologies.

Inverse gas chromatography in the examination of adhesion between tooth hard tissues and restorative dental materials.

The adhesion is a crucial issue in the bonding of dental restorative materials to tooth hard tissues. A strong and durable bond between artificial and natural materials is responsible for the success of the restoration in the oral cavity; therefore it has to be thoroughly examined before new restorative material is introduced to the market and used clinically. Among all methods used to examine bonding strength, most of them require a large number of healthy teeth to be conducted.

Enhancing the Mechanical Properties of Glass-Ionomer Dental Cements: A Review.

This paper reviews the strategies that have been reported in the literature to attempt to reinforce glass-ionomer dental cements, both conventional and resin-modified. These cements are widely used in current clinical practice, but their use is limited to regions where loading is not high. Reinforcement might extend these applications, particularly to the posterior dentition.

The effect of bonding system application on surface characteristics of bovine dentin and enamel.

The main objective of this study was to examine the surface changes of bovine teeth hard tissues (dentin and enamel) after surface preparation with the use of commercial 3-component etch-and-rinse bonding system. Surface composition changes, morphology, BET specific surface area and surface energy parameters were examined after etching, application of primer and adhesive. Characteristic of tissues composition was carried out with the use of Raman spectroscopy.

The effect of petroleum jelly, light-cured varnish and different storage media on the flexural strength of glass ionomer dental cements.

This study determined the influence of coating with either petroleum jelly or light-cured varnish and storage medium on the flexural strength of glass-ionomer cements (GIC). The flexural strength of two glass-ionomer cements (Fuji Equia Fil and Ketac Molar Aplicap) was measured. Specimens (2 × 2 × 25 mm) were prepared in three groups: uncoated, coated with petroleum jelly, or coated with light-cured varnish (EquiaCoat) cured for 20 s using a cure lamp (Bluephase G2, Ivoclar Vivadent, Schaan, Liechtenstein).

Heat transfer properties and thermal cure of glass-ionomer dental cements.

Under clinical conditions, conventional glass-ionomer dental cements can be cured by application of heat from dental cure lamps, which causes acceleration in the setting. In order for this to be successful, such heat must be able to spread sufficiently through the cement to enhance cure, but not transmit heat so effectively that the underlying dental pulp of the tooth is damaged. The current study was aimed at measuring heat transfer properties of modern restorative glass-ionomers to determine the extent to which they meet these twin requirements.

Surface energy of bovine dentin and enamel by means of inverse gas chromatography.

Adhesion between tooth tissues and dental fillings depends on the surface energy of both connected materials. Bond strength can be determined directly or indirectly as a work of adhesion on the basis of values of surface energy of these materials. Inverse gas chromatography (IGC) is one of the methods of surface energy examination.

Adhesion of resin-modified glass-ionomer cements may affect the integrity of tooth structure in the open sandwich technique.

Objective: To study the interfaces between model cavities prepared in teeth and four glass ionomer cements (two conventional and two resin-modified).

Methods: Ten non-cavitated molars and premolars were used and, in each, two 3mm deep slot preparations were created on opposing sides of the tooth. The teeth were conditioned as appropriate, then restored using the open sandwich technique, using a conventional glass ionomer (Fuji IX, Ketac Molar) or resin modified glass ionomer (Fuji II LC or N100), followed by completion with composite resin.

Maturation affects fluoride uptake by glass-ionomer dental cements.

Objectives: Four commercial glass-ionomer cements have been studied for their ability to take up fluoride from aqueous solution following variable maturation times in the dry at 37°C.

Methods: Sets of five specimens of four different materials were cured for times of 10 min, 24 h and 1 month, then transferred to a neutral solution of NaF at approximately 1000 ppm in fluoride. Fluoride concentration was then measured at regular time intervals up to 1 month using a fluoride ion selective electrode.

Effect of denture cleansers on chemical and mechanical behavior of selected soft lining materials.

Objectives: The aim of this investigation was to determine the effect of storage in disinfectants and artificial saliva on a series of commercial soft lining materials for dentures. Changes in mechanical properties and the nature of chemicals released into these solutions were studied.

Methods: Four soft lining materials were studied (Vertex Soft® and Villacryl Soft®, both of which are plasticized acrylics; Molloplast B® and Mollosil®, both of which are silicone elastomers).

Shear bond strength of epoxy resin-based endodontic sealers to bovine dentin after ozone application.

The idea of using ozone to disinfect root canals is of recent origin. The wide acceptance of epoxy resin-based sealers lead us to investigate whether ozone can influence the adhesion to the dentin. In this study, we tested the shear bond strength of AH Plus and EZ Fill.

Review paper: Role of aluminum in glass-ionomer dental cements and its biological effects.

The role of aluminum in glass-ionomers and resin-modified glass-ionomers for dentistry is reviewed. Aluminum is included in the glass component of these materials in the form of Al(2)O(3) to confer basicity on the glass and enable the glass to take part in the acid-base setting reactions. Results of studies of these reactions by FTIR and magic-angle spinning (MAS)-NMR spectroscopy are reported and the role of aluminum is discussed in detail.

[Smoking and periodontal disease--results of an epidemiological survey].

A questionnaire concerning oral health designed for young people aged between 18 and 30 and based on one produced by Tokyo University entitled Medical Outcome Study (MOS) and Oral Health Score) 8020, was submitted to a group of Poznan citizens. One of the 10 questions in the OHS part of the questionnaire concerned smoking habits. A condition for participation in the survey was an absence of professional or educational connections with medicine, dentistry or pharmacy.

The biocompatibility of resin-modified glass-ionomer cements for dentistry.

Objectives: The biological effects of resin-modified glass-ionomer cements as used in clinical dentistry are described, and the literature reviewed on this topic.

Methods: Information on resin-modified glass-ionomers and on 2-hydroxyethyl methacrylate (HEMA), the most damaging substance released by these materials, has been collected from over 50 published papers. These were mainly identified through Scopus.

The kinetics of water loss from zinc phosphate and zinc polycarboxylate dental cements.

The water desorption behaviour of three different zinc oxide dental cements (two polycarboxylates, one phosphate) has been studied in detail. Disc-shaped specimens of each material were prepared and allowed to lose water by being subjected to a low humidity desiccating atmosphere over concentrated sulfuric acid. In all three cements, water loss was found to follow Fick's second law for at least 6 h (until M(t)/M(infinity) values were around 0.

Kinetic studies of water uptake and loss in glass-ionomer cements.

The water sorption and desorption behaviour of three commercial glass-ionomer cements used in clinical dentistry have been studied in detail. Cured specimens of each material were found to show slight but variable water uptake in high humidity conditions, but steady loss in desiccating ones. This water loss was found to follow Fick's law for the first 4-5 h.

Ion release by endodontic grade glass-ionomer cement.

Cylindrical specimens (6 mm high x 4 mm diameter) of the endodontic grade glass-ionomer (Ketac Endo) were exposed to various media for 1 week, after which changes in their mass, pH of storage medium, and ion release were determined. In water, this cement was shown to release reasonable amounts of sodium, aluminium and silicon, together with smaller amounts of calcium and phosphorus, as well as taking up 2.41% by mass of water.

Kinetic studies of the effect of varnish on water loss by glass-ionomer cements.

Objectives: This paper reports a study of the water loss behaviour of two commercial glass-ionomer cements coated with varnishes.

Methods: For each cement (Fuji IX Fast or Chemflex), specimens (6mmdiameterx2mm depth) were prepared and cured for 10min at 37 degrees C. They were exposed to a desiccating environment over H(2)SO(4) either uncoated or coated with the appropriate varnish (Fuji Varnish, a solvent-based lacquer, or Fuji Coat, a light-cured varnish).

Shear bond strengths of glass-ionomer cements to sound and to prepared carious dentine.

The aim of this study was determine whether bonding of glass-ionomer cements to non-carious dentine differed from that to carious dentine. Five commercial cements were used, namely Fuji IX GP, Fuji IX capsulated, Fuji IX Fast capsulated (all GC, Japan), Ketac-Molar and Ketac-Molar Aplicap (both 3M-ESPE, Germany). Following conditioning of the substrate with 10% poly (acrylic acid) for 10 s, sets of 10 samples of the cements were bonded to prepared teeth that had been removed for orthodontic reasons.

Ion release by resin-modified glass-ionomer cements into water and lactic acid solutions.

Objectives: This study was undertaken to gain a fuller picture of the interaction of resin-modified glass-ionomers with aqueous solutions in terms of water sorption, solution buffering and ion-release.

Methods: Two commercial materials were employed (Fuji II LC, GC; Photac Fil Quick, 3M ESPE). Light-cured cylindrical specimens (6mm highx4mm diameter) were prepared and stored for up to 6 weeks in either water (pH 5.