It should be clear that direct palatal access presents important advantages in the preservation of labial intact enamel like the case presented in this post giving better esthetics as well.
Execution of prophylaxis with a rubber cup and prophylactic paste is implemented before shade selection.


 

The operatory sequence begins with the demarcation of the occlusal contacts with a piece of articular paper.
⛔️ A preliminary examination of occlusal contacts is an important reference to define the limits of the cavity. Contacts should not be present in the region of the interface between the restoration and the tooth structure since it compromises the longevity of the restoration. Thus in case of contacts at the interface, the execution of an occlusal adjustment is possible and recommended before the restorative procedure in order to transfer the points of contact to an area located entirely on tooth structure.


Although the carious lesion is not directly involving the buccal surface, the shade selection should be carefully performed. In addition to the lesion being slightly visible from an oblique view, it is important to remember that the dental tissues are translucent, and even restorative materials used in the restoration of the body and palatal surface influence the optical aspect of the labial surface.

In this case, the shade selection was performed using small pellets of the composite which are light-cured for the appropriate time.


Preparation phase

The next step is to isolate the operatory field effectively. The use of a rubber dam is strongly recommended. To facilitate access to the lesion a slight dental separation is performed using wooden wedges. Often, the height of the wedge can compromise viewing and limit access to decayed tissue. In such cases, small modifications with a disk or a scalpel blade are needed to allow for access to the cavity.



The same wedges adapted previously, now have the function of holding a metal matrix which serves to protect the adjacent tooth during removal of caries, performed at low speed with smooth spherical burs.


Which bur should we use?


The selection of burs with appropriate dimensions is undoubtedly one of the most operatory cares to combine effectiveness (speed) and safety (preservation of tooth structure) during the preparation of cavities.
Burs larger than the lesion may extend the preparation beyond that which is desired and therefore are not recommended.

In contrast, very small burs are not effective and make the removal of caries unnecessarily time-consuming and may further facilitate the occurrence of pulpal exposure.

Evidently, the ideal bur diameter should be compatible with the size of the carious lesion, and in most situations, it is necessary to use burs of different diameters according to the stage of preparation.

As a general rule, the preparation should be started with the largest bur available, provided it does not exceed the dimensions planned for the cavity. Then, progressively smaller burs should be used according to the location and extent of the area to be prepared. Critical care should be taken especially in the preparation of class III cavities when evaluating the dentin-enamel junction. Even after removing all the decayed tissue, it is common that the dentin-enamel junction remains stained by its highly organic nature. Although this staining is not necessarily synonymous to infected tissue, it should be removed with a small rounded bur to increase the chances of a successful aesthetic restoration.

Restoration phase

After caries removal, the cavity is cleaned and bonding procedures are initiated.
1️⃣ Insert a polyester strip between tooth to be restored and the wooden wedge to restrict the action of phosphoric acid gel to the tooth that is being restored. This care is especially important during composite insertion otherwise there is a risk the teeth will remain bonded at the end of the restorative procedure.
2️⃣ Apply the acid for 15 seconds, rinse and remove the excess moisture.

3️⃣ Apply the adhesive in at least two layers. Solvents are volatilized gently with air-jets and the surface is then light-cured.

4️⃣ Start the insertion of the composite after the hybridization of the dental tissues. The first composite mass is applied to the proximal enamel and has low saturation and higher translucency than the dentin masses. This first increment is positioned with the aid of thin spatulas against the labial wall of the preparation and the Mylar strip.
5️⃣ Remove the wedge and then pull the matrix towards the labial aspect to adapt the increment of composite resin perfectly to the preparation margins. The lack of tension in the matrix in cases like this can lead to imperfections in the tooth-restoration interface.
Note that after removal of the matrix, the composite is in direct contact with the adjacent tooth surface. Once the adjacent tooth has been properly protected during bonding procedures, there is not any risk for the teeth to be bonded. At the moment the proximal enamel is reproduced and properly contoured, the increment of composite resin can be light-cured for the time recommended by the manufacturer.


6️⃣ After the reconstruction of the proximal enamel, insert a second layer of composite resin, now corresponding to dentin, a more saturated and less translucent. Dentin is reproduced next to the desired final contour in the palatal aspect. It is essential that space left usually around 0.5 mm so that a final layer of composite with optical characteristics similar to enamel is used. Then light curing is performed.

7️⃣ The last composite layer covering the palatal enamel is inserted and shaped with the aid of spatulas and preferably brushes since they facilitate the production of very smooth surfaces. Then light curing is performed.
At this point, the basic anatomy of the restoration is now complete although minor corrections of the shape are required as well as achieving the correct texture and suitable surface luster.


8️⃣ The finishing step starts with the separation of the restoration and the adjacent tooth by inserting a spatula into the incisal embrasure and executing a slight twisting force. Then the proximal excesses are removed with a #12 scalpel blade with movements from the tooth structure to the restoration to avoid inadvertent removal of composite in the region of margins. At this point, the restoration now presents contour nearly ideal.


9️⃣ The rubber dam is removed in order to allow for the polishing and finishing procedures.
🔟Finishing and polishing are performed with abrasive strips and discs. Then the contacts are checked and if necessary adjusted with extra-fine diamond points or multi-laminated burs until they are similar to that recorded before the restoration. The finishing of the palatal surface is made with abrasive rubber and polishing with Robinson brushes and special pastes.

The result is very pleasant when preserving the natural tooth structure in the labial surface and reproducing the shape and aesthetics of the palatal and proximal surfaces through the use of composites. Finally, the restoration is virtually invisible, thanks to the correct mimicking of shape and color.