introduction: the aim of this in vitro study was to compare polymicrobial microleakage of calcium enriched mixture (cem) cement, mineral trioxide aggregate (mta), amalgam, and composite resin as intra-orifice sealing materials. materials and methods: seventy single-rooted mandibular premolars were instrumented and obturated by cold lateral compaction technique. the teeth were randomly divided i...

AIM The aim of this study was to investigate the association of different degradations on the roughness, gloss, and color changes of microhybrid composites. MATERIALS AND METHODS Ten specimens were prepared for Charisma, Amelogen Plus, Point 4, and Opallis resins. Surfaces were polished and baseline measurements of roughness, gloss, and color were recorded. Specimens were then submitted to ch...

PURPOSE This study evaluated whether a Class II restoration in a flowable resin composite has to be placed prior to (open-sandwich technique) or after (closed-sandwich technique) construction of the interproximal wall in the centripetal build-up technique in order to reduce microleakage. METHODS AND MATERIALS Thirty non-carious molars were selected and randomly divided into two groups (n = 15...

OBJECTIVES This study aimed to evaluate the color stability of bulk-fill and nanohybrid resin-based composites polished with 3 different, multistep, aluminum-oxide impregnated finishing and polishing disks. MATERIALS AND METHODS Disk-shaped specimens (8 mm in diameter and 4 mm in thickness) were light-cured between two glass slabs using one nanohybid bulk-fill (Tetric EvoCeram, Ivoclar Vivade...

AIMS Tooth colored dental restorative materials should maintain their chromatic properties throughout their service period. The aim of this study was to examine the possible color changes of flowable resin composite filling materials following water storage. The effect of additional light curing on color stability of restorative materials was also investigated. MATERIALS AND METHODS Six brand...

Possibilities for the " parasitic " collection of power from human walking motion are explored. The focus is on the walking action as a source of power because of the extensive range of motion and large dynamic forces associated with the heel strike and the bending of the sole. Two piezoelectric systems: a multilayer laminate made from PVDF foil and a unimorph piezoceramic composite (PZT); as w...

To ensure an adequate clinical composite filling light source for photopolymerization is of great importance. In everyday clinical conditions commonly used unit for polymerization of composite material is halogen curing unit. The development of new blue superbright light emitting diodes (LED) of 470 nm wavelengths comes as an alternative to standard halogen curing unit of 450-470 nm wavelengths...

AIMS The aim of this in vitro study was to evaluate the influence of light curing modes and curing time on the microhardness of a hybrid composite resin. METHODS AND MATERIALS Forty-five Z250 composite resin specimens (3M-ESPE Dental Products, St. Paul, MN, USA) were randomly divided into nine groups (n=5): three polymerization modes (conventional-550 mW/cm2; light-emitting diodes (LED)-360 m...

The purpose of this study was to examine the effects of LEDs on the polymerization of dental composite resins. Three composite resins and two LED units were used to evaluate the latter's effects on microhardness and temperature rise. In particular, two composite resins contained a coinitiator in addition to camphorquinone (CQ). The emission peak of the tested LEDs matched well with the absorpti...

The polymerization shrinkage of composite resins may affect negatively the clinical outcome of the restoration. Extensive research has been carried out to develop new formulations of composite resins in order to provide good handling characteristics and some dimensional stability during polymerization. The purpose of this study was to analyze, in vitro, the magnitude of the volumetric polymeriz...