Stainless Steel Crowns (SSCs), often called “silver teeth,” are durable restorations used in pediatric dentistry for primary teeth. These pre-formed metal caps protect a tooth from extensive damage until it is naturally lost. A frequent concern is whether this restoration interferes with the natural process of tooth loss. The entire structure, including the crown, is designed to come out on its own when the permanent tooth is ready to emerge. This biological mechanism remains unaffected by the presence of the crown cemented to the tooth.
What Are Stainless Steel Crowns and Why Are They Used
Stainless Steel Crowns are prefabricated caps made from a durable alloy, typically containing nickel and chromium, that covers the entire surface of a damaged primary tooth. Unlike a traditional filling, the SSC provides full coverage, creating a protective shield against further decay and fracture. This comprehensive protection is useful when primary teeth have extensive decay on multiple surfaces or have undergone pulp therapy.
SSCs are the preferred method for restoring severely compromised primary molars due to their longevity and strength. Primary molars must remain functional for years to aid in chewing and maintain correct spacing for the permanent teeth developing underneath. Placing an SSC preserves the tooth’s function and ensures the space required for the succeeding adult tooth is held open. The procedure is often quick, involving the dentist selecting a pre-sized crown and cementing it onto the prepared tooth structure in a single visit.
How Primary Teeth Shed Naturally (Crown and All)
The loss of a primary tooth is governed by root resorption, or rhizolysis. This natural process involves the gradual dismantling of the primary tooth’s root structure to make way for the developing permanent tooth. The crown is a passive covering cemented to the top of the tooth and does not interfere with the activity occurring deep within the jawbone.
As the permanent tooth forms and moves upward, it stimulates specialized cells called odontoclasts to dissolve the primary tooth’s root. These cells systematically break down the hard tissues of the root, including the cementum and dentin. This resorption starts at the root tip and progresses toward the crown over a period of months or years.
The stainless steel crown is tightly bonded to the remaining, non-dissolving upper part of the primary tooth structure. Since the entire root is being dissolved from below, the primary tooth loses its anchor in the jawbone and becomes mobile. The SSC remains tightly attached to the remnants of the primary tooth’s crown and is exfoliated right along with it. This fulfills its purpose of protecting the tooth’s integrity until the moment of natural shedding.
Scenarios Requiring Dental Intervention
While the crown should naturally fall out with the tooth, certain complications may necessitate dental intervention.
Premature Dislodgement
One common issue is premature dislodgement, where the crown becomes loose or comes off entirely before the tooth is ready to shed. This often happens due to sticky or chewy foods pulling on the restoration. If a crown comes off, the dentist should be contacted immediately, as the underlying tooth structure is now exposed and vulnerable to decay or sensitivity.
Swallowing the Crown
If a child accidentally swallows the crown, parents should contact their dentist or physician. The smooth, small nature of the SSC means it typically passes harmlessly through the gastrointestinal tract and is excreted in a few days. Medical guidance is necessary to monitor for rare signs of aspiration or intestinal obstruction.
Over-Retention
Over-retention occurs when the crowned primary tooth does not shed on time, even though the permanent tooth has begun to erupt. If the root resorption process stalls, the primary tooth remains firmly in place. This can force the permanent tooth to erupt into an incorrect position. In these cases, the dentist must extract the crowned primary tooth to allow the permanent tooth to move into proper alignment.