Basic rules for class IV restorations
Restoration of the anterior teeth is always one of the most difficult challenges for doctors, since there is always a risk not to get into color, and this can lead to the future mistrust of the patient. Following the basic principles of color matching and the layering of composites we can turn our daily routine work in to the excellent aesthetic results.
Img. 1 – Before restoration.
Img. 2 – We started with color check for dentin and enamel with the button try technique.
Img. 3 – To make sure that we choose the right color we always check with VITA shade guide and following the Styleitaliano recipe we can easily restore this defect with 2 shades.
Img. 4 – Checking color with cross polarization filter. For this we can use the camera with filters or a mobile phone with the help of Smilelite.
Img. 5 – Isolation of the treatment area provides the ability to create an aseptic and dry environment and improves manual control together with efficiency. We use photodam fot this case and it gives a good contrast. Note the sclerotic dentin in the tooth which had to be removed in order to obtain a better adhesion.
Img. 6 – All sharp edges were rounded up and 2 mm bevel was placed. For creating bevel we use a diamond bur with a yellow marker.
Img. 7 – Or soflex coarse discs too.
Img. 8 – For better adhesion and for removing aprismatic enamel we can use sandblaster ( Aquacut or Rondoflex) with 27 micron aliminium oxide sand.
Img. 9 – After isolation of adjacent teeth with mylar matrix strips (or teflon tape), selective etching technique is used on the enamel for 30 seconds.
Img. 10 – Right after rinsing of etching gel.
Img. 11 – We start to apply the new generation of adhesive (multilayer) by brushing actively, much on the the dentin and less on the enamel. We must wait minimum 20 seconds for the exposition of the adhesive followed by 5-10 second air drying for removing the sovent. Light cure for 60 seconds.
Img. 12 – First, palatal shell restored with the silicone key technique. We used the same enamel shade that will be the last layer of vestibular enamel. The thickness of the palatal shell can be 0.3 to 0.5 mm.
Img. 13 – Second phase: mamelon base was created using the dentin composite. The same dentin shade we used for the incisal edge. The dentin mass is calibrated with the Misura instrument from LM Arte set; the composite excess is removed and the incisal edge is modeled in order to leave space for translucent masses and for the final enamel layer
Img. 14 – Layering of the final enamel layer with LM Arte Modella instrument, followed by smoothening with brushes.
Img. 15 – The final stage of our layering must always be air isolated with glycerine. Curing for 1 minute.
Img. 16 – We need 3 main phases to obtain a good polishing: contouring, finishing and polishing. With Soflex discs we start the contouring phase of our restoration.
Img. 17 – Second phase is finishing. In order to get smooth margins we use carbide bur from StyleItaliano Finishing Kit.
Img. 18 – To create the illusion of perykimata we always use diamond Perio bur from StyleItaliano Finishing Kit at a very low speed without water irrigation.
Img. 19 – Third phase is polishing. With a rubber abrasive point we start the final procedure.
Img. 20 – Polishing is finished with a silicone abrasive wheel.
Img. 21 – Final view of restoration
Img. 22 – Final view after rehydration
Img. 22 – Before and after restoration.
With simple techniques and protocols we can easily overcome the challenges this kind of hard cases always present.