The new generation of resin composite materials in combination with modern layering techniques allows today’s practitioners to treat their patients with minimally invasive, highly aesthetic direct restorations. Due to their enhanced properties, these materials produce results that are hardly distinguishable from the natural dentition, especially with regard to colour, which is particularly desirable in anterior teeth.
The new composite IPS Empress Direct enables us to create restorations that are almost invisible to the human eye. The appropriate increment technique together with correct handling of the materials and high-gloss polishing produces predictable, aesthetic results directly in the mouth. Because of its nanohybrid structure, the material can also be used to restore posterior teeth.
IPS Empress Direct materials are available in various levels of opacity, translucency and brightness. By combining the different materials, tooth-like light scattering can be achieved. The working steps of the technique used to place IPS Empress Direct are described in this article.
Clinical case
A young patient presented with a defective resin composite filling in tooth 11. The margin was no longer tight and the interface between the tooth structure and the restoration showed staining. What is more, the chroma, opalescence and shade of the filling did not correspond to that of the natural dentition (fig 1).
According to the treatment plan the filling would be removed and the cavity prepared along minimally invasive principles and the tooth restored with a direct resin composite. To achieve impeccable integration of the restoration in the oral environment and an aesthetic smile line with a uniform colour, the composite would have to be placed using the increment technique. As the cavity had walls on all sides, there was no need to create a wax-up or a silicone template to restore the tooth shape. A layering scheme was established before the treatment started.
During the dental examination and the general preoperative situation, the natural colour of the patient’s teeth and individual characteristics were photographically documented. The layering scheme was prepared on the basis of the photographs. The different materials that would be used for the restoration were established in the process. To reproduce the special characteristics of the patient’s tooth anatomy, the appropriate dentin and enamel shades were selected along with an opalescent material and a white-opaque material (from the IPS Empress Direct range).
At a second appointment, the operating field was isolated with a rubber dam, since absolute moisture control is indispensable in the placement of resin composites (fig 2). The outer margins of the old filling were traced with a pencil. This was done to highlight the transition between the filling and the tooth structure in the removal of the old filling. A small chamfer was prepared on the vestibular side, as this is indicated for this type of restoration (fig 3). Next, the enamel and dentin were etched with 37-percent phosphoric acid (Total Etch) and a three-component adhesive (Syntac) was applied (figs 4 and 5).
To obtain the desired tooth shade, the dentin part of the restoration was built up first with dentin material (IPS Empress Direct Dentin A2) (fig 6). A translucent and opalescent material (Trans Opal from the IPS Empress Direct range) was used to build up the enamel part (fig 7). Thin white-opaque strips (IPS Empress Direct Bleach XL) were applied over the dentin segment to enhance the brightness. Finally, an appropriately shaded enamel material (IPS Empress Direct Enamel A2) was placed over the entire facial surface of the restoration to cover all the previously placed materials (fig 8).
The creation of surface texture along with the finishing and polishing are important working steps in imparting a restoration with a true-to-nature appearance. In the present case, the surface texture was created with diamond burs at low speed. This allowed the procedure to be precisely controlled. A three-step silicone polishing system (Astropol) was used to finish and polish the restoration. Finally, the restoration was polished to a high gloss finish using aluminium oxide and diamond pastes (Shiny System, Micerium) and brushes and felt wheels.
It is worthwhile to recall the patient for a third appointment to make sure the restoration blends into the natural environment when the tooth is moist and to establish whether or not any shape or colour adjustments need to be made (fig 9).
Contact Anna by emailing annasalat@hotmail.com or for more information visit www.ivoclarvivadent.co.uk