A cemented dental crown is a permanent restoration designed to cover a damaged or weakened tooth, restoring its shape, size, strength, and appearance. It is secured onto the prepared tooth structure using a strong dental cement, which forms a durable bond intended to last for many years. Despite the precision involved in its creation and placement, patients frequently experience discomfort or an uneven bite immediately after the permanent cementation. In most cases, a crown can be successfully adjusted even after it has been permanently placed, addressing these initial concerns.
Adjusting the Bite and Surface
The most common adjustment needed for a new crown involves correcting the occlusion, or the way the upper and lower teeth meet when biting down. Even a fraction of a millimeter of height difference can feel significant to the patient, causing discomfort or jaw pain over time. The dentist uses a thin, colored material called articulating paper, which the patient bites down on to mark the points of contact on the crown’s surface.
These marks pinpoint the “high spots” where the crown is making excessive contact with the opposing tooth. Using a specialized, fine-grit dental bur, the dentist reduces the material in these marked areas, effectively reshaping the biting surface. This chairside procedure is quick and painless, as the crown material has no sensation. Once the bite feels balanced, the adjusted area is polished smooth to prevent rough edges that could irritate the tongue or trap plaque.
This adjustment process is limited to the outer surfaces of the crown, primarily the chewing surface and sometimes the sides. Minor tweaks to the crown’s contour can also be made to ensure it does not impinge on the gum tissue or feel bulky. These surface modifications are the primary method for resolving post-cementation issues, allowing the crown to function naturally without the need for more invasive procedures.
When External Adjustments Are Not Possible
While surface adjustments fix most bite-related issues, there are specific structural problems that cannot be solved by simply grinding the crown. One significant problem is a marginal gap, which occurs when the crown’s edge does not perfectly meet the prepared tooth structure near the gum line. This gap allows oral fluids, bacteria, and food particles to seep underneath the crown, leading to decay of the underlying tooth or chronic sensitivity. Since the crown is fixed by the cement, this fit issue cannot be corrected with external reshaping.
Deep, persistent sensitivity or throbbing pain often indicates an issue with the tooth’s nerve (pulp), which may have been irritated during preparation or exacerbated by a pre-existing issue. In such cases, the solution involves either root canal treatment, which may be performed through the crown, or the complete removal of the crown to access the tooth structure beneath.
Issues with the crown’s general contour or the contact point with an adjacent tooth can sometimes necessitate a remake. If the crown is incorrectly shaped, it may create an area that is impossible to clean, leading to gum inflammation, or it may press too hard against a neighboring tooth. These structural flaws are often diagnosed through X-rays and cannot be fixed by minor surface polishing, requiring the restoration to be replaced for long-term oral health.
The Process of Removing a Cemented Crown
When a crown cannot be saved by external adjustments, removal becomes the last resort to address the underlying issue. The first method involves specialized crown removal pliers or devices that attempt to break the cement seal with controlled force. While sometimes successful, this technique carries the risk of damaging the tooth underneath or the crown itself.
With very strong permanent cements, the crown must often be sacrificed by cutting it off. The dentist uses a high-speed dental bur to carefully cut a slot through the crown, typically from the biting surface down to the margin. This sectioning weakens the structure, allowing the pieces to be gently pried apart and removed. This process almost always destroys the crown, making it unusable.
Following removal, the underlying problem, such as decay or a necessary root canal, is addressed. Since the original crown is usually destroyed, a new impression is taken, and a temporary crown is placed to protect the tooth while a new, custom-fitted permanent crown is fabricated. The complexity of removal and replacement highlights why adjustments are always the preferred initial course of action.