There are a number of pros and cons associated with both composite and porcelain, and amalgam.
Safety and Appearance: In addition to having a more pleasing and natural tooth-like appearance, porcelain and composite fillings have the potential advantage of not containing mercury or other metals that may contribute to sensitivity or toxicity. Mercury toxicity from amalgam fillings is a controversial subject, though no research to date has been able to show any risks of having mercury as a component of amalgam fillings. However, many patients do have metal sensitivities and some have reported a metal taste after the placement of amalgam.
Durability: Porcelain and composite previously were not as durable as amalgams. However, dental manufacturers have made great strides in improving the strength of composite resin materials, to the effect that composite fillings now have the potential to be used for all teeth, including molars. Furthermore, composite materials often require less tooth preparation and may not weaken the affected tooth as much as amalgam, which often require more extensive tooth preparation. However, amalgam fillings do have a long-term track record and may last longer than porcelain and composite.
Tooth Shaping: All fillings require preparation of the affected tooth, but less preparation is usually required for porcelain or composite. Typically, this means that less healthy tooth structure has to be removed when placing a composite.
Technique and Time: More than amalgam, the success of porcelain or composite depends on your dentist's technique. Porcelain or composite restorations also require the use of additional equipment, and the procedure itself requires up to 50 percent more time than the amalgam filling procedure. These factors contribute to the higher costs associated with porcelain and composites. In addition, most dental insurance companies do not cover the additional costs associated with porcelain and composite.
Skill: Most dentists are skilled in porcelain and composite fillings, but their level of skill may vary. Selecting the appropriate dentist is an important factor in treating tooth decay or similar damage. Ask if your dentist has obtained the kind of post-graduate education that allows dentists to refine their skills in porcelain or composite restorations.
If you spend some time understanding the differences between the various restorative procedures and the materials used for each, you will be better informed as to the option that works best for you. Consult with your dentist to determine the treatment time, cost, functionality and aesthetic value of all available restorative treatments for decayed or damaged teeth.