Skip to main content Skip to header navigation

A guide to your child’s first cavity

Your child’s dentist says that dreaded word — cavity! After you recover from your mommy guilt, there are many choices to face. Do cavities in baby teeth need to be filled? Which fillings are best? What are the out-of-pocket costs of these choices?

Boy at dentist

When a child gets their first cavity, the first question is usually this: Is it my fault? While it’s true that cavities can be caused by improper brushing and flossing, a sugary diet and lack of fluoride, there are other factors over which you have less control. The shape of the teeth, how close they are in the mouth, parental dental history and the unique composition of mouth bacteria all play a role in predisposition to cavities.

Do baby teeth need fillings?

Baby teeth eventually fall out, so why fill them? The problems with leaving a cavity untouched can range from mild to severe. At minimum, anything from dental sensitivity to pain may result. At worse, an abscess and infection could occur. The worst case scenario is that the infection could spread to the brain and even be fatal. If a child has to lose a decayed tooth prematurely, there is an effect on how the permanent teeth grow in. Baby teeth are there for a reason — to hold the place for adult teeth. For all of these reasons, filling a cavity is usually the recommended course of treatment.

Amalgams vs. composites: What’s the difference?

One burning question that concerns mothers is whether to get the amalgam (silver) or composite (white) fillings. Cost is certainly a deciding factor, but many mothers are more concerned with the mercury levels in amalgams.

The amalgam controversy arose because these fillings are 50 percent mercury, a known neurotoxin. Studies vary on the health risks of mercury in the mouth leaching into the body. Following a lawsuit, the FDA agreed to post a warning about the neurotoxic effects of mercury vapors released through chewing as being possibly harmful to children. The American Dental Association, however, continues to defend the use of amalgam fillings as safe, citing 150 years of supporting research.

White fillings, or composite resin, are made from acrylic plastics, quartz fillers and colorants. Composite fillings are increasingly popular, yet they are not as durable and therefore less apt to be covered by insurance.

Amalgams and composites both have their pros and cons, and weighing them will help you make the best decision for your child, your wallet and your peace of mind.

Amalgam (silver)


  • More durable so they last longer
  • Less expensive
  • More insurance coverage so less out-of-pocket cost
  • Take less time, so less time in the dental chair

  • They contain mercury, a toxic metal
  • More tooth structure is lost because a bigger preparation area is needed
  • Amalgams expand over time, so the filling may fracture

Composites (white)


  • More natural looking
  • Preserves more tooth structure so less drilling
  • No toxic mercury

  • Lasts half as long as amalgams
  • May stain
  • Costs an average of 25 percent more than amalgams so more out-of-pocket expense
  • Takes longer for the dentist to fill, so more time in the chair

In general, 80 percent of fillings are covered by insurance but composites are more expensive. Most dental plans cover composites up to the cost of the amalgams and the patient is responsible for the difference. Some insurance plans cover composite fillings on teeth where there is more cosmetic benefit. Talk to your dentist, research your choices and be sure the dental office contacts your insurance provider for an estimate of total cost.

More about kids’ dental health

A checklist for choosing a pediatric dentist
Prepare your child for the dentist
Teaching kids about dental health

Leave a Comment

Comments are closed.