For the young patient from Liege confronted by generalized tooth wear, this “conservative” philosophy which favors tissue preservation prevailed in tandem with a multi-disciplinary approach. The surgical techniques (with, for example, the fitting of implants) and prostheses (by bonding) were planned, combined and associated with the treatment plan.
In fact, the team from Liege did not invent the A to Z of the procedure applied to this patient. It was inspired by the approach applied by the Department of Dentistry of the University of Geneva (Switzerland) where Franscesca Valaiti works. She is the author of numerous publications relating to this non-invasive procedure. But Prof. Vanheusden added his personal touch to the procedures to be followed. He applied a variant procedure which, during one of the treatment stages, makes it possible to lighten the somewhat restrictive procedure followed by the Swiss team. Without negatively affecting the treatment, the practitioner avoided a certain number of occlusal corrections which would normally have had to be carried out in the patient’s mouth.
Three stages, step by step
Unquestionably, restoring teeth as damaged as those of this patient requires a long treatment. “From the outset, the reasons we are applying the treatment must be clearly explained to the patient”, Prof. Vanheusden reminds us. The patient’s level of motivation is an important factor even if only because he must be willing to make the necessary changes to stop the phenomenon of tooth wear.
The treatment care is administered in three steps. During the first step, the occlusion problems are at the center of the therapy. At this stage, it is impossible for the dentist to know the height that needs to be restored and reconstituted exactly for each of the teeth concerned. An estimate has to be made. This procedure must be milimeter perfect. In any event, each space that modifies the architecture of the dental arches must be able to be tolerated by the patient. This factor is what needs to be evaluated first.
Some erosion or tooth wear lesions have been known to cause a loss of what is called the “occlusal vertical dimension” (OVD). When teeth are worn, they do not interlock with the teeth corresponding to them when the jaw is closed. In some cases, this even causes some teeth to move, to “exit” the gum (known as overeruption). In short, the occlusion is disturbed. A new OVD needs to be established which prepares the way for “new teeth” which in time will be reconstituted to the “correct” height.
“During this first phase we advance by trial and error”, explains the practitioner. “First of all, a removable resin splint is made. This serves as a protective shield against tooth wear. Based on the plaster models used to make it, the splint brings about an occlusal elevation in order to compensate for the loss of OVD", continues the Professor (photos). The objective is to monitor the ways in which the patient reacts, that is to say how he tolerates the splint that is used to re-establish the new OVD. This point is essential: it means ensuring that the ceramic restoration fitted during the final phase of treatment will perfectly suit the individual in question.
For three weeks the patient wears this splint which causes an increase in his OVD (from 1 to 5 millimeters). He notes how he is feeling on waking up including any contractions of masticatory muscles. “In the beginning, it is a big change for the patient”, admits the practitioner. “But once the level of tolerance is validated, it becomes our value of reference, the one that we will use during the final restoration of the worn teeth”, he continues.
A provisional procedure that speaks volumes
The second stage can then begin. It leads to the fitting of provisional partial restorations. First of all, after the molding of the current teeth, the prosthetics laboratory makes what are called wax-ups. These wax models are made according to the indications from wearing the splint and the imprint of the mouth.
Once they are made, the wax ups give a precise idea of what each used tooth will look like once it has been restored, in a context where there will be a maximum amount of dento-dental contact between. From the wax ups, resin prostheses are then made. Thin and fragile, they restore the height to the teeth upon which they are provisionally bonded and where they will remain for several weeks.
“At this stage we are still applying a transitional approach, but a more precise one by means of the splint. Indeed, there is no longer any need for the patient to wear a foreign body between the teeth. The individual concerned will live and sleep with these prostheses made from the wax ups. These temporary restorations enable us to confirm that we have achieved a comfortable new OVD. They validate the occlusal modifications which have been carried out and confirm the re-establishment of the different functions. Finally, they make it possible also to appreciate the esthetic benefit of the restoration of the dental morphology”, states the practitioner.
When the situation is adjudged to be stable and satisfactory, the final phase can be envisaged. Of course, any surgical treatment will have been carried out beforehand.
