How long does dental lab keep models?
When you have crowns made, how long does the lab keep the models of your mouth? I had crowns made and I may need them replaced and was wondering if the lab retains the mold ofr a certain amount time?
Could the models be re-used after that?
The lab keeps the models for about three weeks. The lab will send back the finished product as well as your molds!
The lab keeps the models about 7 to 10 days or how ever long it takes them to make the crowns or other dental work. It’s then returned to your dentist with the finished product.
Your dentist is more likely to hold them for a few years, some will give the models to the patients; in most cases after any lengthily time, there are just too many changes in the oral cavity, such as a slight shifting of the teeth that naturally occurs and there are the normal changes in the tissue; these changes would prevent us from using an older model to make a new crown from that would fit with any precision.
It’s also during the removal of the old crown and in cleaning up the prep that may also change the margins slightly, leaving us with a new margin that the old model would not work for.
If it’s been more than a year or two, let your dentist decide if a new impression and model for a new crown would be best.
Another reason for a new impression and model would be if there is decay under the margins of this crown.
You didn’t mention the reason for a new crown, so I‘ll assume that porcelain may have fractured or broke off the crown. In cases such as this the dentist will use extra care in the removal of the crown, in cleaning up the margins of the tooth and may use the old model if it isn’t too old or broken. I feel it’s always better to make a new impression, (especially if this is a newer crown that has fractured) for a remake such as this, unless it’s on a fairly recent crown and possibly the lab work was at fault for the fracture.
Some dentist will use an old model up to five years, although I wouldn’t advise doing this. This is due to the dental insurance, they won’t pay for a new crown or remake during the first five years of placement. If you want the crown to last ten years or even longer, as most do, have a new impression taken and a new model made and floss daily.
In any case don’t make the mistake some patients make thinking it’s a “crown” and it’s indestructible and won‘t decay, they don’t need to floss it. This thinking is SO UNTRUE! It will require you to floss even more than a natural tooth does, because your natural tooth is smooth without flaws. Under this crown lies your natural tooth and at the margin where the crown “meets” the natural tooth is the area that plaque forms easily and decay eventually develops, it’s just not as “smooth” as the natural tooth. So always be sure to floss regularly to prevent decay under your expensive crowns.