Single shade cervical restorations
Cervical restorations of carious or non carious lesions represent a big clinical challenge, and not precisely because of aesthetics. Medium-short term debonding is frequently reported by colleagues all over the world. These cavities, especially the non-carious ones are the most frequently studied for adhesion purposes clinically and in-vitro. Class V restorations in a single shade will certainly solve the aesthetic issue, letting us concentrate in the bonding stage and modeling which are of outmost importance.
In this article we will expose the classical layering approach which is still a valid alternative, some tips about isolation as well and in further articles we will explore new stratification possibilities.
Cervical lesions before any treatment. Look at the lack of enamel and the conditions of the cervical dentin which are extremely full of debris and stains.
It is mandatory to clean teeth for a good adhesion, we suggest air abrasion with glycine powder (is strongly suggested not to use bicarbonate) and immediately after, the placement of the dental dam.
Clamp 212 about to be modified with a universal orthodontic plier, for a better adaptation and visualization of the lesion. The clamp 212A is an alternative which already has the vestibular prong angulated.
The clamp prong can be heated with flame before being folded. It is a dangerous procedure so we suggest either to fold it very slowly without heating, or using specific protection gloves.
To obtain a good exposure of the cervical lesion the vestibular prong is folded by 25-30°.
Clamp in place. Observe how the cervical lesion is exposed. We do one tooth at a time.
2% chlorhexidine in aqueous solution is applied for 2 minutes for a better adhesion (MPP inhibition) and good dentinal tubules disinfection.
Adhesive steps. With the use of a selective acid etching of the enamel and washing the acid generously, we can dry completely the dental substrate without any fear of collapsing the collagen network.
If right opacity is selected, a single mass can be done. As a protocol we use single color in class V lesions to simplify the procedure. In that case the right opacity was found with a composite A3 Body. As it can be seen in the image there is a few amount of composite stratified in an oblique inclination. Different thin layers can be stratified in order to avoid the typical detachment problems in this kind of cavities where the C factor is supposed to be zero, but frequently composite contraction cause white lines.
Layer by layer the tooth is restored. Reduced polymerization times for thin layers, 10 seconds.
Clamp in the next tooth that has to be restored.
The first layer (adhesive) is the most important one so extended curing time is applied (60 sec) avoiding non polymerized adhesive to be in touch with the vital tooth.
Post-operative image after removing the clamp. For a final step we do a final extended polymerization in order to gran a favorable conversion of the composite resin.
Control after 2 years. If any re-intervention would be needed it can be proposed at any time and will be an extremely easy procedure.
Single shade is the daily color protocol used in class V restorations. The real problem in class V restorations is the separation of the material from the cavity. For this reason the correct layering technique is very important. For a better exposition of cervical lesions a modified clamp is a possible solution, specially if they go beyond the cemento-enamel junction.