Custom Rings everyday
The most important tip I have learnt for posterior direct restorations is an extreamly easy thing of an amazing simplicity and advanced performance. Talking about shape, one of the goals for second class composite is to achieve strong contact point while another goal is to obtain a precise proximal contour. The custom ring technique offers both advantages while being an extremely economic solution, easy to do and at the reach of everyone. Thanks to the Styleitaliano team for describing and making available to everyone this technique 3 years ago with their more than 12 articles in www.styleitaliano.org Material needed: – metal ring (Garrison, Palodent) – liquid dam (Opaldam, Gingival barrier) – convex matrices (Garrison, slick matrix) – wooden wedges
Initial Situation, a first upper molar with old composite resins infiltrated and a fresh proximal lesion in the distal. Note how all the proximal embrassures seem intact, although the lesion is evident.
After ruber dam placement a mandatory procedure in proximal lesions is the insertion of a wedge. It will have 3 functions: 1- Separate teeth 2- Squezze the papila 3- Protect the rubber dam
In a classical approach this would be the right time to open the cavity. In this strategy we are going to perform an impression of the proximal embrassures of the first molar. These areas are perfectly healthy but after the cavity opening, cleaning and margin definition the cavity margins must probably end up in an area where generally the matrices do not fit flawlessly. With the blue composite (Block-out resin, Ultradent) we place a small amount in the embrassure area and polimerize, immediately after we place the ring over the polimerized resin.
We add more resin to embrace completely the ring and give another polymerization. At this point we can dettach the ring from the teeth, generally no lubrification is needed.
The ring dettached must stay on the forceps with slight tension in order to avoid the customised tips to touch each other, but not too much tension to avoid deforming the ring.
Detail of the perfectly copied anatomy of the embrasures. These areas will make the matrices adapt better than any other kind of appliance.
After cavity preparation and during disinfection we can place a sectional matrix (Composi-Tight M Bands, or Slick Bands SM, Garrison) which we fix most preferably with the same wedge that we used for preparation stage.
The custom ring should adapt perfectly together with the matrix. At this point we can etch selectively the enamel and place our universal adhesive (ScotchBond Universal, 3M) and polimerize the bonding layer for 1 minute.
We start the stratification by building up the proximal wall tranforming the class II into a class I by the classical centripetal technique. After polimerization, we can remove the ring and the matrix. The mass used was A3B (Filtek Supreme XTE, 3M)
After the removal of the ring and the matrix we can appreciate the lack of composite excess and how precise the composite adapts to the tooth with a very similar anatomy of the original tooth.
For the next layer we like to use a daily strategy with materials that have proven to be very reliable as cavity bases; these are the Bulk Fill materials. We fill the cavity with Bulk Fill resin up to 1,5mm. away from the margin, giving more than enough space for the final layer which will be a body shade. This strategy is called the “Bulk and Body Technique
With the same A3B composite, body is a medium opacity mass, ideal for restoring posteriors with single sahde. Using the sectional modelling technique, which was described in the book Layers (or any other modeling technique of your choice) we create cusp by cusp until we develop the full anatomy in a predictable way.
After finishing the last layer, optionally we can add stains. Is up to the clinician to perform this step or not.
Final aspect of the restoration after occlusion check, finishing and polishing, and waiting for the first year control.
I would like to present you a second case, this was the first time ever I used the customrings technique.
Ring impression on mesial of the first upper molar.
A common mistake is to harm the ring by letting the personalised tips touch each other, causing the resin to rotate and eventually breaking or giving some kind of imprecision or looseness.
Cavity preparation ready for disinfection and matrix placement.
Perfect matrix adaptation by the customring
Build up of the proximal wall… today I would do it less thick.
The restoration finished, if not in an impressive way, with good adaptation and aspect for the duration.
After its publication 3 years ago in styleitaliano.org I became very curious about this technique. I tried to study the history of it and where it was inspired. The most similar thing I could find was in a book published on 1981 by Baum, Phillips and Lund, the strategy was to place acrylic resin to make the matrix super strong to withstand the forces of amalgam and gold condensation. But I have never seen a technique which copies the natural anatomy in such a clever way. Thanks again to the inventors of the custom rings technique and recognition to the people that inspired them.
Update (July 2017).- MyCustomRIng Kit has been released in partnership with Polydentia powered by Styleitaliano, to learn more, follow this link