Silver teeth caps, also known as silver fillings or amalgam fillings, have been used for decades to fill cavities in teeth. While very durable, silver fillings don’t last forever. Over time, they can come loose or fall out for a variety of reasons.
What are Silver Fillings?
Silver fillings are made from a mixture of metals including silver, tin, copper, and mercury. This amalgam mixture is resilient, hard, and durable, which makes it good for filling holes in teeth caused by decay. The dentist first drills out the cavity and then packs the silver filling into the hole before shaping and polishing it.
While amalgam fillings have been around since the 19th century, they have declined in popularity in recent decades in favor of tooth-colored composite resins. However, silver fillings are still used today because they are:
- Durable – They can last 10-15 years with proper care
- Wear-resistant – They hold up well to force from chewing
- Moisture-resistant – They won’t expand or contract with temperature changes
- Cost-effective – Silver fillings are less expensive than composites
Do Silver Fillings Eventually Come Out?
Yes, silver fillings do not last forever. Over time, silver fillings can come loose, fall out, fracture, or develop marginal gaps between the filling and the tooth. On average, silver amalgam fillings last 10-15 years before needing to be replaced, but they can fall out sooner or last longer depending on several factors.
Reasons Why Silver Fillings Fall Out
There are several reasons why silver fillings might become dislodged and fall out of the tooth:
- Decay: If new decay develops around the edges of the filling from poor oral hygiene, it can undermine the bond to the tooth and cause the filling to pop out.
- Fractures: Silver fillings can crack or fracture over time from forces placed on them during chewing. Fractured chunks of the filling can break free.
- Wear: A silver filling’s edges can slowly wear down from constant biting and chewing. This causes it to loosen and eventually fall out.
- Bruxism: Grinding or clenching the teeth puts extreme pressure on fillings and can cause them to dislodge.
- Loose Existing Filling: If an old silver filling is already loose, new fillings placed next to it can cause it to fully come out.
In addition to these reasons, some lifestyle factors can also impact how long silver fillings last:
- Diet: Hard or sticky foods can put more stress on fillings.
- Oral Habits: Nail biting, teeth grinding, or chewing on hard objects promotes wear.
- Medical Conditions: GERD/reflux or bulimia can expose teeth to stomach acid.
How Long Until Silver Fillings Need Replacing?
There is no definite lifespan for silver fillings. However, they usually last anywhere from 10-15 years before needing replacement. The timing depends on several factors:
- Location and size of the filling – Fillings on back teeth tend to last longer than those on front teeth.
- Oral hygiene habits – Good brushing and flossing prolongs filling lifespan.
- Chewing and diet – Hard or sticky foods and aggressive chewing shorten lifespan.
- Grinding or clenching – These habits put excess force on fillings.
- Exposure to acids – Frequent reflux or bulimia erodes filling over time.
With proper oral hygiene and regular dental exams, silver fillings can last upward of 15 years. But they may need replacing sooner with poor hygiene, unhealthy habits, or large fillings in vulnerable areas. At the first sign of loosening, it’s smart to get them replaced preemptively.
Do Silver Fillings Need to Be Replaced?
Silver fillings don’t need to be proactively replaced just because they are old. As long as they remain tightly bonded and intact, they can safely remain in the tooth. However, there are certain situations where replacement is recommended:
- Filling is cracked, fractured or has a gap: This can allow new decay to form and should be replaced.
- Tooth has a new cavity: If a new cavity has formed around an old filling, a new filling is needed.
- Filling is worn down: Exposed silver metal from a very worn filling can cause sensitivity and needs replacement.
- Damaged edge is near the nerve: This can cause pain and inflammation necessitating replacement.
- Tooth needs a crown: Sometimes a crown is the best restoration option, requiring the silver filling to be redone.
- Patient desires improved aesthetics: Silver fillings can be replaced with tooth-colored fillings or inlays.
During your regular dental exams, your dentist will check existing fillings for signs of loosening, fractures, or new decay to determine if replacement is needed.
What Are the Signs That a Silver Filling is Coming Out?
Some clear signs that a silver filling is on its way out and needs to be replaced include:
- You can see part of the silver filling is missing or cracked
- The filling feels rough or jagged to your tongue
- Biting down creates discomfort or pain in the tooth
- You notice a gray/black color showing through at the edge of the tooth
- You feel discomfort when eating or drinking hot/cold foods
- You see a gap between the tooth and filling
- The filling is loose and moves when you push on it
Any of these signs indicate the filling is failing and needs prompt replacement. Leaving a compromised silver filling in place risks new decay, infections, fractures, or loss of the entire tooth.
Can a Silver Filling Fall Out on Its Own?
Yes, it’s possible for a silver filling to spontaneously fall out on its own without warning. This occurs when:
- The bonding between the filling and the tooth has weakened over time
- Chewing forces or bite pressure cause the aged filling to dislodge
- Decay or fracture has undermined the filling’s foundation
Fillings that fall out suddenly on their own are often ones that already exhibited warning signs like cracking or loosening but went unaddressed. However, sometimes fillings do unexpectedly pop out of nowhere, leaving a hole in the tooth and requiring immediate replacement.
Immediate Steps if Your Silver Filling Falls Out
If you lose an intact silver filling, follow these steps:
- Rinse your mouth out thoroughly with warm water to clean the area
- If possible, locate the filling and bring it with you to the dentist
- Make an appointment with your dentist right away to have the tooth evaluated
- In the meantime, avoid chewing on the side with the missing filling
- Use dental wax or chewing gum in the hole to protect the tooth
Leaving a hole from a lost filling exposes the inner tooth to new decay and bacterial infections. Therefore, it’s important to see your dentist promptly, ideally within several days, to get it repaired.
Do Silver Fillings Need to Be Replaced with White Fillings?
| Silver Fillings | White Composite Fillings |
|---|---|
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Silver fillings don’t necessarily need to be replaced with white fillings as a preventive measure. However, there are advantages to opting for white composite resin fillings in these situations:
- Silver filling needs repair or replacement anyway
- Patient wants improved aesthetics
- Older silver fillings are causing discoloration of the tooth
- Patient prefers the adhesive bond of composite fillings
- Silver fillings require frequent replacement from wear
Talk to your dentist about whether white fillings are right for you. They do cost more than amalgam fillings since they require more time and skill to place. But their aesthetic benefits make them a popular choice to consider when getting fillings redone.
Can a Dentist Make Silver Fillings Stay In?
If an existing silver filling is intact but becomes loose, there are steps a dentist can take to re-adhere it and make it stay in place longer:
- Remove debris: Clean out any old cement or decay from under the filling.
- Roughen the surface: Use a drill to create fresh grooves for binding.
- Add new cement: Apply bonding material like glass ionomer to solidly adhere to the tooth.
- Careful bite adjustment: Reshape edges that may be getting excessive force during chewing.
With re-bonding methods like these, a competent dentist may get an older but otherwise sound silver filling to last several more years. However, if the filling is already significantly fractured or deteriorated, replacement is usually the best option.
Can a Silver Filling Be Saved or Does it Need Replacement?
Whether an aging silver filling can be saved or needs full replacement depends on its condition. Fillings with minor issues like small fractures or loosening may be repairable. But those with major defects typically require replacement. Considerations include:
| Filling Condition | Repair or Replace? |
|---|---|
| Small crack in one section | May be repairable with bonding agent |
| Chunk missing from corner | Can often be patched and restored |
| Severe cracks across multiple surfaces | Likely needs total replacement |
| Existing decay around margins | Requires new filling to remove decay |
| Filling intact but totally loose | Difficult to re-bond, needs replacement |
Your dentist will assess the filler under magnification during your checkup. They can then best advise you on whether repair or replacement is the right option. Partial repairs can buy some extra time. But with substantial defects, replacement is usually the permanent solution.
Do Silver Fillings Contain Mercury?
Yes, silver fillings contain mercury. Mercury makes up about 50% of the metal alloy mixture used for amalgam fillings. The other approximately 50% is a blend of silver, tin, and copper.
Mercury was historically used because:
- It bonds the metals together into a stable, strong filling
- It provides plasticity for packing the filling into the tooth cavity
- It hardens rapidly to form a durable filling
However, the use of mercury has also generated some controversy and safety concerns. Once hardened, silver fillings only release trace amounts of mercury vapor. But some people still choose to have them replaced with mercury-free materials for peace of mind.
Mercury Exposure from Silver Fillings
Silver fillings present very little mercury risk, especially when compared to the amounts of mercury people are exposed to from other environmental sources like certain types of fish. Still, anti-amalgam groups argue that mercury vapor release directly into the mouth is dangerous. The evidence on risks is conflicting:
- Some studies show no harm from mercury in dental fillings
- Other studies associate it with negative neurological or kidney effects
- WHO states mercury exposure from fillings is within safe levels for most people
Talk to your dentist about any mercury concerns you have. Composite fillings are a common mercury-free alternative.
Conclusion
Silver amalgam fillings are strong and durable dental restorations. However, like all fillings, they do not last indefinitely. Over an average 10-15 year lifespan, silver fillings can crack, fracture, wear down, or come loose and fall out. This is particularly likely when deep fillings are placed under high stress in the back molars. With good oral care and avoiding chewing habits that put excessive force on teeth, silver fillings can be very long-lasting repairs.
If you notice signs of wear, fracture, loosening, or damage to an existing silver filling, make an appointment with your dentist promptly. In many cases, deteriorating fillings can be repaired or replaced before they fully come out. This protects the underlying tooth and prevents further decay. Regular dental checkups every 6 months also allows early detection of any issues with old fillings before they turn into emergencies.