The results that can nowadays be achieved with direct composite restorations go far beyond simple class I cavities. There are two reasons that can lead to choosing composite instead of indirect ceramic restorations, among which are the patient’s financial condition and the confidence the clinician has about being able to achieve optimum function and aesthetics, while preserving as much sound tissue as possible, with a direct approach.
It is very clear that the cavity design for amalgam restorations can stonefly impact the mechanical resistance of a tooth. In fact, findings such as cracks and thin residual cusps are to be commonly expected when replacing an amalgam.
In this case, two old large amalgam restorations were removed and the teeth restored after appropriate assessment and preparation of the residual tooth structure.
Fig.1
The initial view of the old defective restorations on teeth 36 and 37, under rubber dam isolation.
Fig.2
After the old amalgam restoration was removed, because of the converging cavity design of the amalgam restoration, it is wise to measure the thickness of the remaining cusps in order to decide whether to keep a cusp structure or to reduce it. For this purpose the Cusp Misura (LM Arte kit by StyleItaliano) is very easy to use for a simple and quick assessment of the residual dental structure.
Fig.3
After measuring the thickness of each cusp, the whole surface of tooth 37 was reduced, as well as the disto-lingual cusp of tooth 36.
Fig.4
After the bonding procedures, the cusps are the first part to be built in order to get enough support for the sectional matrices.
Fig.5
All the missing cusps were built by using the P shade from the CompoSite kit (White Dental Beauty). After the circumferential anatomy was outlined, we are ready to build the proximal walls.
Fig.6
The matrices were placed and secured with the ring, with the back to back technique to build the proximal walls.
Fig.7
Here is a quick review of the Back To Back Technique:
- First step shows the two adjacent teeth after cavity preparation.
- Second step shows the placement of the suitable matrix in terms of the contour, height, and thickness.
- Third step shows the placement of the ring while the wall of the first tooth is built.
- Fourth step shows the removal of the ring and the matrix of the built-up tooth.
- Fifth step shows the repositioning of the ring in order to build up the margin of the other tooth.
- Sixth step shows the removal of the ring and the matrix from the second tooth, with a good final contact point.
Fig.8
After the matrices were removed, the case became easier. For the occlusal modelling, the Composite Up Modeling Technique (CUMT) was used for tooth 37, while the Espresso posterior philosophy (Fast Modeling Technique – FMT, as described by Hardan, Akhundov et al.) was used for tooth 36. A single shade approach was used in this case, so the occlusal anatomy was also built using the P shade from the CompoSite kit from White Dental Beauty.
Fig.9
After modeling was done, the restorations were finished and polished. Note that finishing usually takes longer with techniques such as the CUMT technique. In fact, while 5 minutes only were needed to finish tooth 36 (restored using the FMT), 35 minutes were used to finish tooth 37.
Fig.10
Immediate result after rubber dam was removed.
Fig.11
Occlusal contact were checked. High spots were eliminated to create healthy and functional restorations.
Fig.12
2 months follow up showed good healing with no complaints.
Conclusions
Direct composite overlay cases are always a challenge, mostly due to the care needed to restore the correct contour of the missing cusp(s), as well as the contact and guides with the opposing tooth, and the contact area. The combination of multiple techniques, just like in this case, is often a good solution. The back to back technique, the Espresso Posterior philosophy (Fast Modelling Technique), and the Composite Up Modelling Technique were the ones chosen to achieve a good anatomical contact point and a functional occlusal anatomy. Last but not least, such cases require suitable materials, such as CompoSite (White Dental Beauty) to ensure longevity and high polish.
Bibliography
1. Manauta J, Salat A. Layers An Atlas of Composite Resin Stratification. 2012. Quintessence Pub.
2. Hardan L, Sidawi L, Akhundov M, Bourgi R, Ghaleb M, Dabbagh S, Sokolowski K, Cuevas-Suárez CE, Lukomska-Szymanska M. One-Year Clinical Performance of the Fast-Modelling Bulk Technique and Composite-Up Layering Technique in Class I Cavities. Polymers (Basel). 2021 Jun 4;13(11):18733.
3. Marchetti G. “10 TIPS on Posterior direct restoration in daily flow”. 2018. Styleitaliano.org
