In previous blogs I’ve talked about why Preference Soft Denture Liner material is better than chairside soft reline materials. For what it is intended, this is true. However, there are correct applications for chairside soft material and we should agree on those situations.
I’ve seen articles written by clinicians which say that the denture should be relined every six to eighteen months for various reasons on a routine basis. Among these are: changes in the shape of the ridge, bacterial growth and breakdown of the liner. Let’s begin by agreeing that if your patient does not yet have a stable ridge, a chairside soft material is best. As the ridge changes, these temporary soft materials can be used to reline the immediate or first denture, and then easily removed in a short period of time and replaced with new material on a different landscape. Once the ridge has stabilized though, we need to take a look at what configuration will be best for the individual patient. Most will fit into a well-made, that is constructed to a good functional impression, hard denture with no issues. These are the best for bacterial control and overall tissue health, when the patient practices good oral hygiene. If they do not, then similar problems to any other prosthetic interface will raise their heads.
These chairside liners are also great for the temporary reline, while the new denture is being constructed for the immediate denture where a soft healing surface is appropriate, and for patients transitioning into a new screw retained appliance during implant healing stages. They are also good when trying to diagnose areas of consistent pain and its relief, or as a way to quickly diagnose the need for and create an increase in the vertical dimension (open the bite) in an existing denture.
However, once we are beyond these stages and we have a patient with a stable ridge and good hygiene, but who exhibit other factors, like Tori, boney outgrowth, flabby tissue, thin ridge, palatal defects or pain or discomfort with a hard surface denture, then we need to consider a soft surface reline.
The bacteria often associated with these types of chairside and some laboratory relines is often the result of poor hygiene, but also of de-lamination. This is where the reline material separates itself from the denture base and gives the bacteria or fungus (Candida albicans is a dimorphic fungus) a place to grow. This growth can also be supported if the soft liner surface is full of voids or open pores.
Some authors have suggested that RTV Silicones “promote” this growth. There is no chemical property in the RTV that would promote the growth of bacteria or fungus, but the aforementioned conditions would. For example, if you find a black spot of mold in your shower or bathtub and have tried everything to remove it; scrubbing, chemical cleaners, but find nothing works. This is because it is not on top of the silicone nor is it in the silicone, but in between the silicone and the tub or shower material. It is in a spot that has de-laminated. Unfortunately, the only way to remove it is to cut out the silicone and remove the mold. We would need to do the same for a reline if this were the condition.
What is great about the Preference Soft Denture Liner material is that it has a bonder that affixes the material to the denture base and then holds it there while curing at 80psi. This pressure not only keeps the material against the denture base but also promotes a good reduction in the surface pores so that no sealer is required. Then with an easy regimen of care by the patient, this soft reline will last far beyond the replacement time of the chairsides. With the knowledge of the application of these materials by the Laboratory and the Doctor comes the resultant happy smiling patient.