Light-polymerized Composite Resin Research Articles

Use of light-polymerized composite resin to stabilize ball attachments during transfer procedures

Ball-type attachments are commonly used for implant-retained overdentures. The matrix is designed to be rotational to the path of insertion of the denture, especially for situations with multiple implants (Fig. 1). Securing the matrices during the transfer procedure, therefore, is important. Stabilizing devices (Directional ring; BioHorizons Implant Systems, Inc, Birmingham, Ala) are available; however, the devices have only 3 different degrees of inclination and may not be able to orient the matrices to allow for optimal parallelism. The attachments or the abutment undercutsmust be blocked out before connecting the matrices to the denture. The use of rubber dam material has been proposed in the literature, but this material cannot stabilize the matrices during the transfer procedure. Keys suggested using the orthodontic rubber spacer to secure the matrices, but the draw of the matrices must follow the axis of the implant. The material used for the blockout of the ball-type attachments must be stiff and easily contoured and removed. This article presents a technique using lightpolymerized composite resin to stabilize the matrices and block out the undercut during the transfer procedure.

Effects on adhesive strength to tooth substance to be caused by the concentrations of the light-sensitive agent in an ultraviolet light polymerized composite resin.

Effects on adhesive strength to tooth substance to be caused by the concentrations of the light-sensitive agent in an ultraviolet light polymerized composite resin.

Conversion in different depths of ultraviolet and visible light activated composite materials.

Studies by means of infrared multiple internal reflection spectroscopy of ultraviolet and visible light polymerized composite resin materials indicated that the degree of conversion below the surface is nearly constant for most of the materials investigated until a depth is reached where the degree of conversion rapidly decreases. The maximum depth of cure has also been measured for some proprietary dental composite resin materials. This investigation has demonstrated that the conversion at different depths and the maximum curing depth are dependent on the composition of the composite filling material, light source, and exposure time. With respect to the activating system it was found that with visible light activated materials larger curing depths were obtained than with ultraviolet light activated materials. Better results with respect to curing depth were also obtained with materials containing conventional inorganic fillers than with those containing so-called microfillers.The limiting factor for tota...

Restoration of fractured incisors with an ultraviolet light polymerized composite resin : WATKINS J. I. and ANDLAW R. J.Br. Dent. J.142 (1977) 249–252

Restoration of fractured incisors with an ultraviolet light polymerized composite resin : WATKINS J. I. and ANDLAW R. J.Br. Dent. J.142 (1977) 249–252

Primate Pulpal Response to Ultraviolet Light-Polymerized Direct-Bonding Material Systems

The results of this study, plus those of a previous study, show that a layer of CaOH lining the floor of the tooth cavity will protect the dental pulp against toxic irritants inherent to an UV light-polymerized cavity liner and a UV light-polymerized composite restorative resin. This study also showed that a layer of CaOH lining the floor of the cavity will protect the dental pulp against acid irritants inherent in the enamel etching solution. It is recommended to restorative dentistry that all primary dentin within clinically accessible areas of the cavity preparation be covered with a layer of CaOH before the enamel is etched with the acid-conditioning solution. Precautionary protection of primary dentin in this manner affords a margin of safety should the conditioning solution inadvertently spill onto the primary dentin during the enamel-etching procedure. Second, if the conditioning solution does accidentally spill onto the previously placed protective layer of CaOH during the enamel-etching procedure, then it logically follows that this acid-contaminated layer of CaOH should be mechanically removed and a new layer of CaOH that completely lines at least the floor of the tooth cavity should be placed before the resins are applied.