An interim fixed prosthesis is a dental term also known as a temporary fixed partial denture or bridge. In cases where a fixed or non-removable bridge has been planned, a temporary one is used until the final or definitive one is inserted. It should be kept in mind that the interim prosthesis is indeed temporary. While the final one is made of ceramic and/or metal, the temporary one is made of acrylic, which is a type of plastic. As a result, it is not as strong or durable as the final one, and may stain with certain foods as well as over time. When necessary, it may be repaired or replaced relatively easily and inexpensively. It also acts as a guideline to the laboratory as to the shape or colour of the teeth in the final prosthesis. Once your teeth have been prepared, the interim prosthesis will provide you with a pleasing appearance and the ability to function normally, that is to eat and speak, until the final prosthesis is inserted.
In order to receive a fixed partial denture or bridge, the teeth that will support the bridge must be reduced somewhat in order to accommodate the prosthesis. To protect the teeth from sensitivity or breakage, a temporary bridge will be made. An outline of the bridge, which may be custom-made ahead of time, will then be adapted internally to the prepared shape of your teeth. Acrylic material will be mixed and placed into the mould, which will then be inserted into the mouth until the material sets. During this time, you may experience some warmth in the area, which occurs when the material is setting.
The warmth will endure only momentarily, at which time the mould will be removed from the mouth. The interim bridge will then be smoothed and polished, and then tried back in the mouth in order to check the occlusion or “bite”.
Once it fits appropriately, the interim bridge will be cemented with temporary cement, and may require some further minor adjustments. You should be able to carry out your normal daily routines while wearing the temporary bridge. However, you should refrain from using it to chew on hard foods or from frequently using mouthwashes containing alcohol, which may dissolve the cement. If the bridge breaks or comes off between scheduled appointments, please notify your dentist immediately to have it repaired, replaced, or re-cemented.
A well-made interim fixed prosthesis should serve you well both aesthetically and functionally until the insertion of the final fixed prosthesis.