This young patient has already received root canal treatment and crown on her front tooth 21. Due to further trauma, this tooth fractured at the gingival level resulting in no ferrule with poor restorative prognosis.
She is not emotionally ready to proceed with extraction and implant replacement. In addition, she has declined the option for pre-restorative orthodontic extrusion. She is aware that restorability is compromised and is to be considered as a medium-term option only. In the long term this restoration is likely to fail where extraction with implant replacement would be required. With this in mind, we have placed a direct fibre-reinforced post with composite resin core-build-up.
To achieve sufficient ferrule effect, a subgingival circumferential long-bevel margin was carefully created. Great care was placed during subgingival preparation to protect the soft tissue wherever possible as the biological width was invaded.
A good 1-step impression was able to be taken to capture all the subgingival details.
A great amount of time was spent on the construction of a provisional crown (which is critical in this case) to facilitate soft tissue healing, to aid communication with the patient regarding aesthetics tooth anatomy and with the ceramist regarding tooth micro-anatomy and texture.
The material of choice for this case is a porcelain fused to gold crown with circumferential gold margin which offers the best marginal seal and the ability to use a luting cement (as opposed to a resin cement) given the subgingival nature of the crown margin.
Our ceramist is able to replicate all the micro tooth anatomy as well as the surface texture from the contra-lateral tooth.
Resulting in an aesthetically pleasing outcome that is difficult to discern. Because of the optimal seal between the crown margin and the well-polished tooth surface, despite the circumferential subgingival crown margin, the soft tissue response is non-inflammatory and stable in the long-term. This patient is very pleased with the result and feels assured regarding her teeth. We have bought her a number of years to accept the eventuality of this tooth.
For selected cases and the right patient, this technique can also be used to manage teeth requiring deep restorative margins. The below case is a patient who presented with her referring dentist (and long-term friend) for the management of teeth 47 and 46, both of which are heavily restored with minimal ferrule. Tooth 46 carries a guarded to poor restorative prognosis because of the deep distal caries lesion as well as the compromised distal root structural integrity. Tooth 47 carries a guarded restorative prognosis due to minimal remaining tooth structure. The patient is extremely motivated to save both teeth because she believes that she is a “fighter” and she simply cannot “give up”.
In addition, she is currently receiving Prolia injections for the management of osteoporosis where there is a risk of medication related osteonecrosis of the jaw (MRONJ) development after surgical procedures including tooth extraction and crown lengthening surgery. She has excellent oral hygiene and is most realistic of the prognosis of these teeth. Therefore, by combining the patient’s medical history, rationality, personality and motivation, we have decided to place indirect crown restorations on both teeth utilising subgingival circumferential crown margins to achieve optimal marginal seal, ample ferrule effect, sufficient retention and resistance form. Despite the deep restorative margin, there is no soft tissue inflammation. Using this technique we have managed to achieve a stable outcome for now and a happy well-motivated patient.