Anterior Resin Restorations: A Technique For Predictable Class IV Restorations

In my last article “Anterior Resin Restorations: Which Resin Do I Use?”, I wanted to give a quick overview of the many different composite resin materials available, as well as their ideal area of use. In this article we're going to put that information to use and describe a technique that I have learned from leading clinicians for completing Class IV resin restorations (as well as for adding to incisal edges) that is predictable, straightforward and will blend in naturally to the surrounding tooth structure.

For this patient a shade was immediately taken to avoid the tooth from desiccation and having an impact on the final outcome of shade selection. Often, one of the struggles with developing your final restoration in cases like this is the ability to reproduce the anatomy of the loss tooth structure. You can either freehand it (which I find difficult to do, especially in the mouth) or you can make it easier by developing a guide to work off of (great for cases that you already have models and have had waxed up). In this instance, the patient was an emergency case (Fig. 1) and was anesthetized; an alginate impression was made by the assistant and poured in a fast setting stone (Snap – Stone from Whipmix).

Once the stone was set (usually in five minutes or less), the assistant can add wax or old composite in the area of the fracture and then develop a lingual putty stent (Fig. 2). After it set hard, remove the stent and trim the facial aspect back to the facial incisal line angle (Fig. 3, green line). Seat the putty stent in the mouth and check for a passive fit, and scribe a line in the putty with an explorer (Fig. 3, black line) along the area that is fractured.

You can isolate the tooth and complete an initial 45⁰ bevel (Fig. 4, marked in blue) and then feather your finish line out in an irregular pattern to help blend in your final restoration (Fig. 4, marked in yellow). Complete your bonding procedure using your bonding system of choice and you are now ready for the next step. Place a thin layer of composite in the matrix to the scribe line and pull the composite resin up onto the incisal edge (facial-incisal line angle) as well as the mesial and distal line angles (Fig. 5).

For this layer, I like to use an enamel shade in a microhybrid and of course, you can now use the nanohybrid composites. The main reason for this is for strength and support of the final restoration. Now, place it in the mouth, align it with the tooth and apply pressure. This should allow nice adaption to the tooth and you can now cure it and remove the matrix (Fig. 6). You now have a perfect place to layer composite and develop the restoration to blend it perfectly with the adjacent teeth and only requires minor polishing to remove any flash and minimizes finishing. In the next series, I will show you a brief overview of the layering technique that is used to help you complete a natural restoration.

Jeff Lineberry DDS, Visiting Faculty, Spear Education [ www.jefflineberrydds.com ]