In this study, the stress distribution in the shrinkage process when a light-cured composite resin is irradiated with light was estimated. We assumed that shrinkage and hardening of the light-cured composite resin resulted from light irradiation and was the same as that caused thermally. On the basis of this assumption, we simulated the deformation during the shrinkage of the composite resin us...

OBJECTIVES To determine the static load-bearing capacity of direct composite onlay restorations made of novel filling composite resin system which combines short fiber-reinforced composite resin (FC) and conventional particulate filler composite resin (PFC). METHODS Three groups of onlay restorations were fabricated (n = 8/group); Group A: made from conventional particulate filler composite r...

Aim: The purpose of this study was to assess chlorhexidine effects on plaque index and salivary levels of mutans streptococci (MS) when used as the immersion solution for removable orthodontic appliances and added to their acrylic resin composition. Methods: Forty-five patients (6 to 12 years old) were randomly assigned into three groups with 15 patients each. Group I (control)—without orthodon...

For the development of new orthodontic elastic material, 1-butanol was added to PEMA-TA/HX resin. In the present study, basic experiments to reveal the mechanical properties of the materials were conducted. FT-IR spectroscopy showed that addition of 1-butanol did not cause any chemical changes to the PEMA-TA/HX resin. After addition of 1-butanol to PEMA-TA/HX resin, the modulus of elasticity, i...

OBJECTIVES The purpose of this longitudinal prospective randomized study was to evaluate the clinical reliability of two different types of postorthodontic treatment retainers: a silanised-treated glass fibers-reinforced resin composite (FRC) and a directly bonded multistranded stainless steel wire. The hypothesis of the study was to assess if significant differences are present between failure...

The flexural strength and flexural modulus of an experimental metal-resin composite, which used Ag-In alloy particle as the filler, were evaluated. The effect of acid treatment and heat treatment on the Ag-In alloy particle was investigated. The flexural strength of the experimental metal-resin composites ranged from 65.5 MPa to 91.0 MPa. The flexural strength of the metal-resin composite incre...

PURPOSE The purpose of this in vitro study was to determine the effects of short- and long-term storage on the shear bond strength of metal, polycarbonate, and ceramic orthodontic bracket bases using autopolymerizing resin composite and resin-modified glass ionomer cements (RMGIC). The glass ionomer cement was applied in both a wet and a dry environment. METHODS With a method developed in the...

OBJECTIVE To evaluate the effects of contamination by either blood or a hemostatic agent on the shear bond strength (SBS) of orthodontic buttons. METHODS We used 45 freshly extracted, non-carious, impacted third molars that were divided into 3 groups of 15. Each tooth was etched with 37% phosphoric acid gel for 30 s. Human blood or the blood stopper agent was applied to the tooth surface in g...

Resin Composites Sandwich restorations and Curing techniques Anders Lindberg, Department of Dental Hygienist Education, Faculty of Medicine, Umeå University, 901 87 Umeå, Sweden. Since the mid-1990s resin composite has been used for Class II restorations in stress-bearing areas as an alternative to amalgam. Reasons for this were the patients’ fear of mercury in dental amalgam and a growing dema...