Are Metal Fillings Safe?
Yes, metal fillings, also known as amalgam fillings, are considered safe by major dental and health organizations including Health Canada and the Canadian Dental Association. They have been used in dentistry for over 150 years and have an extensive safety record. However, there are important considerations around who should and should not receive amalgam restorations, and modern alternatives now offer equally durable options with additional advantages in aesthetics and biocompatibility.
If you have questions about your existing fillings or are considering your options for a new restoration, speaking with a Dental Clinic in Bolton, ON will give you clear, personalized guidance based on your oral health needs and medical history.
What Are Metal Fillings Made Of?
Dental amalgam is a metal alloy composed of approximately 50 percent elemental mercury combined with a powder mixture of silver, tin, and copper. The mercury in amalgam is what binds the other metals together and gives the material its durability and malleability during placement.
The word “mercury” understandably raises concerns for many patients. However, the mercury in amalgam fillings behaves differently from the organic mercury (methylmercury) found in fish and environmental contaminants. In amalgam, mercury is chemically bound to the other metals, making it significantly more stable. The levels of mercury vapor that amalgam fillings release are extremely low and are well within levels considered safe for most people.
That said, it is important to understand the full picture, including who may benefit from choosing an alternative material.
How Long Have Metal Fillings Been Used?
Amalgam has been used as a dental filling material since the 1800s. For most of that history, it was the dominant material used for filling cavities in back teeth due to its exceptional durability and relatively straightforward placement technique. An amalgam filling placed in a posterior molar can withstand the substantial chewing forces in that area of the mouth and may last 10 to 15 years or longer.
Dental Care in Bolton, ON has evolved alongside the development of new materials and techniques. While amalgam remains in use in some clinical contexts, tooth-colored composite resin fillings have become the most commonly placed restoration in modern dental practice.
Who Should Avoid Amalgam Fillings?
While amalgam is safe for the majority of patients, Health Canada and dental organizations recommend that certain groups avoid amalgam restorations when alternatives are clinically appropriate:
- Pregnant women and women planning pregnancy: A precautionary approach is recommended due to the potential for mercury vapor exposure to the developing fetus
- Breastfeeding mothers: Mercury can pass through breast milk, and alternative materials are preferred
- Children under six: Young children are more sensitive to mercury exposure, and composite resin is the preferred material
- Patients with kidney disease: Kidneys are involved in mercury excretion, and impaired kidney function may affect the body’s ability to process mercury safely
- Patients with mercury allergies: Some individuals have documented sensitivity to mercury or other components of amalgam
If you fall into any of these categories, it is important to inform your Dentist in Bolton, ON so they can plan your treatment with alternative materials from the outset.
Amalgam vs Composite Resin Fillings: A Comparison
| Feature | Amalgam | Composite Resin |
|---|---|---|
| Appearance | Silver/grey, visible | Tooth-colored, blends naturally |
| Durability | Very high | High, continues to improve |
| Placement time | Faster | Slightly longer |
| Mercury content | Yes | None |
| Suitability for back teeth | Excellent | Very good |
| Suitability for front teeth | Not recommended | Ideal |
| Average lifespan | 10 to 15+ years | 7 to 10 years |
| Environmental impact | Requires disposal management | Lower environmental concern |
For patients seeking tooth-colored restorations, Bolton Park Dentistry offers modern composite resin fillings that are both durable and aesthetically seamless. Bolton Park Dentistry is one of the best dental clinics in Bolton, ON, and their team provides thorough consultations to help patients choose the right material for their situation.
You can reach Bolton Park Dentistry at (647) 496-2336, by email at info@boltonparkdentistry.com, or visit their clinic at 14 Parr Blvd #5, Bolton, ON L7E 4H1, Canada.
Should You Have Your Existing Amalgam Fillings Removed?
This is one of the most frequently asked questions regarding metal fillings, and the answer requires careful consideration. Major dental health bodies, including the Canadian Dental Association, do not recommend the routine removal of intact, well-functioning amalgam fillings. Here is why:
- Removing an amalgam filling generates a temporary spike in mercury vapor exposure during the drilling process
- An intact amalgam filling releases minimal mercury vapor
- Removing and replacing a filling unnecessarily reduces the remaining tooth structure, making the tooth more vulnerable in the long run
- There is no clinical evidence that removal of intact amalgam fillings improves health outcomes in otherwise healthy adults
Removal may be appropriate if:
- The filling is cracked, broken, or leaking
- There is new decay forming around the edges of the filling
- You fall into one of the at-risk groups described above and a new restoration is needed
- You are undergoing a full smile restoration or cosmetic treatment and wish to replace silver fillings with tooth-colored options
Step-by-Step: What Happens When a Filling Is Placed
Understanding the process helps patients feel prepared and comfortable during their appointment.
Step 1: Examination and diagnosis Your dentist examines the tooth visually and with X-rays to determine the extent of the cavity and the most appropriate material for the restoration.
Step 2: Anesthesia Local anesthesia is administered to numb the tooth and surrounding tissue. You will feel no pain during the procedure.
Step 3: Decay removal Using a dental drill or laser, the dentist removes all decayed tooth material. The cavity is cleaned and shaped to prepare it for the filling.
Step 4: Material placement For composite resin, the material is applied in layers and each layer is cured (hardened) with a special blue light. For amalgam, the material is mixed and packed into the cavity while soft, then allowed to harden.
Step 5: Shaping and polishing The filling is shaped to match the natural contour of the tooth and polished to a smooth finish. Your bite is checked and adjusted if necessary.
Patients interested in learning more about Dental Filling in Bolton, ON can explore the range of bonded filling options available at Bolton Park Dentistry, including tooth-colored composite restorations that provide a strong, natural-looking result.
Common Mistakes Patients Make Regarding Fillings
- Delaying treatment for a small cavity: Small cavities are quick and simple to fill. Left untreated, they grow deeper and can eventually require more extensive treatment such as a crown or root canal.
- Assuming pain means a new filling is needed: Sensitivity after a new filling is common and usually temporary. Not all tooth pain indicates a new cavity.
- Choosing to have amalgam removed without clinical reason: Patients who insist on unnecessary removal may end up with more weakened teeth and unnecessary short-term mercury exposure.
- Not mentioning allergies or sensitivities before treatment: Always disclose any known material sensitivities before a filling is placed.
Prevention: How to Make Your Fillings Last Longer
Good oral hygiene and lifestyle habits significantly extend the life of any dental restoration. Here are practical tips:
- Brush twice daily with fluoride toothpaste, paying close attention to the margins around existing fillings
- Floss daily to remove plaque and food debris from between teeth where fillings are common
- Attend regular dental checkups so your dentist can monitor the condition of existing restorations
- Avoid chewing on ice, hard candy, or pens, which can crack fillings and enamel
- Wear a custom nightguard if you grind your teeth, as bruxism significantly accelerates filling wear
- Limit sugary and acidic foods that accelerate decay around the margins of restorations
Frequently Asked Questions
Q1: Are amalgam fillings being phased out in Canada? Canada has committed to phasing down the use of dental amalgam in alignment with the Minamata Convention on Mercury, an international environmental treaty. This does not mean existing amalgam fillings need to be removed. It means that alternative materials will increasingly be used for new restorations, particularly in vulnerable groups.
Q2: How do I know if my old fillings need replacing? Your dentist will assess your existing fillings at each checkup. Signs that a filling may need replacing include visible cracks, gaps between the filling and tooth, sensitivity to temperature, pain when biting, or X-ray evidence of decay forming beneath the filling.
Q3: Are white fillings as strong as silver fillings? Modern composite resin materials have improved significantly and are suitable for most cavity types, including those in back teeth that bear considerable biting force. While amalgam still has a slight durability edge in very large restorations, composite resin performs excellently in the vast majority of clinical situations.
Q4: Is it safe to eat after a filling? For composite resin fillings, which are hardened immediately during placement, you can eat as soon as the local anesthesia wears off, typically within one to two hours. For amalgam fillings, patients are usually advised to wait at least 24 hours before chewing hard foods on that side.
Q5: Can a cavity come back under a filling? Yes, a condition called secondary or recurrent decay can develop around the margins of a filling if oral hygiene is inadequate or if the filling begins to break down. Regular checkups and good brushing habits are the most effective ways to prevent this.
Conclusion
Metal amalgam fillings are safe for most people and have served as a reliable restorative material for generations. However, the availability of modern tooth-colored alternatives means that patients now have excellent options that are both durable and mercury-free. The most important step is to have a thorough conversation with your dentist about your specific oral health needs, medical history, and preferences, so the right material can be selected for each individual restoration. Regular checkups ensure that all fillings, old and new, remain in good condition and continue to protect your teeth effectively.