5 Reasons to Replace Metal Fillings

dental illustration of a metal filling being placed in molar

For decades, metal or amalgam fillings have been the go-to solution for treating cavities due to their durability and cost-effectiveness. However, with the evolution of dental materials and growing aesthetic demands, many patients and practitioners are revisiting their restoration choices. This blog will explore the top five reasons you might consider replacing your metal fillings, from health considerations to the pursuit of a perfect, pearly white smile. 

Understanding Metal Fillings

Metal fillings, also commonly known as amalgam fillings, are a type of dental material used to fill cavities caused by tooth decay. They are called “amalgam” because they are an amalgamation, or mixture, of multiple metallic elements, such as:

  • Mercury: Despite concerns over its use, mercury continues to be used in dental amalgam due to its unique ability to bind metals together into a durable and malleable substance. It makes up about 50% of the compound.
  • Silver: Contributes to the strength and stability of the filling.
  • Tin: Improves the workability and strength of the amalgam.
  • Copper: Added to modern amalgam mixtures to enhance durability and reduce the likelihood of corrosion.

Some amalgams may also contain small amounts of zinc, indium, or palladium to further modify the physical and chemical properties of the filling.

Amalgam has been used for over 150 years in dentistry and has been a staple due to its durability, ease of application, and relative cost-effectiveness. The material is known for its long-lasting wear and ability to withstand the forces of biting and chewing, making it suitable for filling cavities in the back teeth, where chewing load is greatest. However, with the introduction of new dental materials, many dentists are recommending the replacement of old metal fillings. 

5 Reasons to Replace Metal Fillings

Aesthetic Appeal

Replacing metal fillings with modern alternatives primarily transforms the aesthetics of a patient’s smile, eliminating the metallic glint that often detracts from a natural look. Metal fillings can be especially conspicuous when they are located in areas that show during talking or laughing, or even result in a discolored appearance to the surrounding tooth over time. Advances in dental restorative materials now offer high-quality, tooth-colored options such as composite resins and ceramics that can be matched precisely to the natural shade of the teeth. These materials blend indistinguishably with the tooth enamel, providing a seamless and more visually appealing finish. For those conscious of the beauty and harmony of their smile, upgrading to these new restoratives means a significant cosmetic improvement, enhancing confidence and ensuring that their fillings are virtually undetectable.

Health and Safety Concerns

Health and safety concerns provide compelling reasons for replacing metal fillings. Although the use of amalgam has been supported by many health organizations, the presence of mercury—a known toxin—has led to an undercurrent of concern among health-conscious individuals. While the levels released by fillings are typically low, there is an ongoing debate about the potential long-term exposure effects, particularly in sensitive groups such as pregnant women and children. Moreover, the potential for mercury to accumulate in the environment has made its use less desirable from a public health perspective. Mercury-free fillings, made from composite resins, glass ionomers, or ceramic materials, eliminate the risk of mercury exposure and the associated environmental issues. These alternatives not only provide safety benefits but also meet the rising demand for holistic and biocompatible dental care, thereby ensuring patients of a safer and more sustainable choice for dental restorations.

Preservation of Tooth Structure

The preservation of tooth structure is a critical advantage in the case for replacing metal fillings. Traditional amalgam fillings require the removal of a considerable amount of the tooth to create a mechanical lock to hold the filling in place, which can weaken the inherent strength and integrity of the natural tooth. By contrast, modern filling materials such as composite resins can be more conservatively placed, as they bond directly to the tooth structure and require less removal of the healthy tooth. This bonding process not only preserves as much of the natural tooth as possible but also restores its original strength, minimizing the risk of future fractures and providing a more stable and long-term solution. As dental philosophy moves increasingly towards minimally invasive techniques, the shift towards materials that protect and conserve the natural dentition becomes ever more pertinent, offering a compelling rationale for the replacement of metal fillings.

Reduced Sensitivity

Another reason to consider replacing metal fillings is the benefit of reduced tooth sensitivity. Metal fillings are excellent conductors of heat and cold, which can lead to discomfort when consuming hot or cold beverages and foods. This sensitivity occurs because the metal transmits temperature changes quickly into the tooth, which can irritate the nerve inside. On the other hand, composite fillings and other modern restorative materials have insulating properties that offer a buffer against such rapid temperature changes. Patients with composite fillings often experience a significant reduction in the incidence and severity of temperature sensitivity, providing not only a more comfortable eating experience but also a consistent sense of relief from the thermal shocks that can come with metal restorations. This enhanced comfort is a key factor in the growing preference for composite fillings over their metal counterparts.

Durability and Longevity Concerns

Durability and longevity are important factors to consider when evaluating the condition of metal fillings. While metal fillings are known for their durability and long service life, they are not without their longevity concerns. Over time, metal amalgam can weaken and break down, leading to the development of cracks in the filling or the tooth itself due to the expansion and contraction of metal with temperature changes. This can create hidden gaps where bacteria can enter and cause decay under the filling. Also, constant pressure from chewing may cause the metal to fatigue and create fractures within the tooth. By replacing old metal fillings with modern materials such as composite resins or ceramics, which bond directly to the teeth and may more evenly distribute the force of biting and chewing, patients can potentially extend the life of their fillings and reduce the risk of future dental work. These materials also tend to require less removal of the tooth structure, preserving the strength of the tooth and supporting its long-term health. Hence, considering a replacement could mean not only a more robust dental restoration but also a safeguard against the need for more extensive dental procedures in the future.


In conclusion, the replacement of metal fillings presents a multifaceted benefit to dental health and personal well-being. With aesthetic improvements through the use of tooth-colored materials, health and safety advancements eliminating mercury concerns, preservation of tooth structure with less invasive preparations, reduced sensitivity to temperature fluctuations, and enhanced durability and longevity, the modern dental patient has much to gain from considering this transition. Although metal amalgam has served many generations with reliability, the evolution of dental science offers superior alternatives that align with current health standards and cosmetic expectations. By opting for the latest in restorative dental materials, patients can enjoy a natural-looking smile and peace of mind, knowing that their dental restorations are designed for their health, comfort, and lifestyle.

Dr. Sam Sadati wearing black suite portrait

Dr. Sadati possesses extensive experience in all aspects of advanced restorative dentistry, with an emphasis in cosmetic and implant dentistry.  He has attained Accredited Fellow status in the American Academy of Cosmetic Dentistry (AACD), the most rigorous, demanding credentialing process in the world. He is the only AACD Accredited Fellow in South Florida.