Insights into and relative effect of chitosan-H, chitosan-H-propolis, chitosan-H-propolis-nystatin and chitosan-H-nystatin on dentine bond strength.

Objective: The purpose of the study was to design and evaluate novel functional chitosan hydrogels (chitosan-H-propolis, chitosan-H-propolis-nystatin and chitosan-H-nystatin) by using the chitosan-H polymer as "dual function restorative materials".

Materials And Methods: The nystatin/antioxidant carrier gel was prepared by dispersion of the corresponding component in glycerol and 3% acetic acid with 5% chitosan gelling agent was then added to the dispersion with continuous mixing. The natural bio-adhesive functionalized chitosan hydrogels were combined with built in drug delivery system and bio-actives such as propolis in order to increase the dentin bond strength capacity and maintain therapeutic properties of the alternative drug delivery system.

Awareness of complications of oral piercing in a group of adolescents and young South African adults.

Objectives: Intraoral piercing as a body art has been gaining popularity amongst adolescents and young adults; however there is limited data on the awareness to complications associated with it. This study investigated the awareness of complications of oral piercing among a group of adolescents and young South African adults with intraoral piercings.

Study Design: A total of 250 patients with intraoral piercing were asked to complete a questionnaire on the awareness of complications of oral piercing and were then examined by two calibrated dentists to determine oral complications caused by the pierced ornament.

Microleakage and confocal laser studies of 2 single-step self-etching bonding agents/systems.

Objectives: This study investigated the microleakage, etching ability, and dentin-restorative interface of 2 different single-step self-etching bonding agents with compomers as restoratives.

Method And Materials: Fifteen extracted noncarious human premolars were used for each dental material system. The bonding agent Xeno III was used with their compomer Dyract AP (Dentsply) and Adper Prompt L-Pop with their compomer Z2000 (3M Espe).

Coronal leakage of teeth root-filled with gutta-percha or Resilon root canal filling material.

This study compared the micro-leakage of a root canal filled with Resilon or gutta-percha (GP), utilizing either cold lateral condensation or System B. Four experimental groups were used. Group one was obturated with GP using cold lateral condensation, group two with GP using System B, group three with Resilon using cold lateral condensation, and group four with Resilon using System B.

Effect of LED curing on the microleakage, shear bond strength and surface hardness of a resin-based composite restoration.

To determine the effect of Light emitting diode (LED) curing on dental resins, microleakage, shear bond strength and surface hardness of a dental composite cured with different LEDs were determined and compared with conventional halogen curing. For microleakage, Class V cavities were restored with Esthet-X, divided into groups, and exposed to one of the curing protocols (Elipar Freelight in soft start and standard modes; Ultra-Lume 2; Spectrum 800). Standard dye penetration tests were performed and the data summarised in a 2-way contingency table of observed frequencies.

Effect of LED curing on microleakage and microhardness of Class V resin-based composite restorations.

Background: Polymerisation shrinkage is a critical limitation of dental composites and may contribute to microleakage, postoperative pain, tooth fracture, and secondary caries. It has been shown that curing methods play a significant role in polymerisation shrinkage of light-cured dental resins. The purpose of this study was to investigate the effect of a LED curing light on microleakage as well as microhardness of a dental composite.

Effect of power density on shrinkage of dental resin materials.

This study compares volumetric changes and rates of shrinkage during different stages of polymerization of dental resin composites and compomers exposed to the same total energy by using two different combinations of power density and exposure duration. A hybrid composite and its equivalent flowable and a compomer and its equivalent flowable were exposed using a halogen curing unit set at 400 mW/cm2 for 40 seconds and 800 mW/cm2 for 20 seconds: delivering 16 J/cm2 in both cases. Volumetric changes were recorded every 0.

The effects of light intensity and method of exposure on the hardness of four light-cured dental restorative materials.

Aim: To determine the microhardness of several light-curing dental restorative materials at the top surface as well as at a depth of 2mm.

Methods: Comparisons were made using different light sources. Four groups of five specimens each (3mm diameter, 2mm thick) of Z250 (composite), Filtek Flow (flowable composite), Dyract AP (compomer) and Dyract Flow (flowable compomer) were cured using different methods of exposure.

The effect of different power densities and method of exposure on the marginal adaptation of four light-cured dental restorative materials.

Purpose: To determine whether marginal adhesion is sensitive to different irradiation parameters, we investigated the in vitro adhesion values of four dental resins on metal surfaces.

Methods: Four groups of eight specimens each of Z250, Filtek flow, Dyract AP and Dyract flow were placed in pre-treated stainless steel cavities and irradiated using different methods of exposure. The curing lights used were a Spectrum 800 halogen curing light at settings of 800 and 450 mW/cm(2) and an Optilux 501 ramping light.

The effect of an additional flowable compomer layer on microleakage of Class V compomer restorations.

Background: Polymerisation shrinkage and the associated stress on composite resins and surrounding structures have been regarded as a major cause of leakage and clinical failures in modern polymer restorations. The purpose of this study was to investigate the effect of an additional flowable compomer layer on the microleakage of Class V dental cavities, which were further filled with a compomer.

Method: Cavities (32) were prepared in human premolars, conditioned with a non-rinsing agent (Prime & Bond NRC) and treated with the bonding agent (Prime & Bond NT).