Crowns under partials present problems that usually require special attention from dental laboratories.
Patients should expect to be without their partial dentures for several days while a crown is being fabricated by the dental laboratory.
Precision fabrication is desired in order to make the crown, usually porcelain, fit the clasps and framework of an existing partial denture.
To construct a crown in this manner requires normal preparation of the tooth structure.
The existing partial is checked to make sure the partial and tooth reduction are adequate for the crown fabrication.
If not enough clearance exist between the tooth preparation and the partial framework, binding will not allow the crown and partial to fit together properly.
With the partial denture seated into place over the teeth a pick-up impression is taken to show dental laboratory technicians the relationship of the prepped tooth and the partial denture framework.
This special technique provides a good record of the tooth to partial denture relationship.
In most cases the cementation of the crown appointment is not a problem and flows smoothly.
The goal of this procedure is to get the partial back into the mouth as soon as possible in order to prevent teeth from shifting out of alignment with the partial denture.
In the event too much time elapses, shifting of teeth can make the cementation of the crown and partial denture alignment a lengthy appointment so that parts involved can be re-aligned.
Requesting the patient leave the partial in the mouth, initially, for longer periods of time assists in the re-alignment process.
On rare occasions the partial is remade to synch with the new crown.
It is easier to remake the partial than to cut away the permanent crown.
One technique used in regaining stability of the partial denture on the side of the interference, is the placement of a tissue conditioner underneath the saddle to keep movement to a minimum.
This technique also in the short term, stabilizes the partial helping to re-align all parts involved.
The liner also serves as a tissue treatment and it can be removed at the end of treatment in a couple of weeks.
Crowns under partials are necessary to keep teeth functional and restored back to normal form.
From the Diary of my enlightenment,
A.L. Clark, D.D.S. http://www.dentist4you.biz