Tooth Decay: Do Cavities in Baby Teeth Need to be Filled?

Deciduous teeth are commonly known as baby teeth, milk teeth, or primary teeth. When children get cavities or tooth decay, parents often ask their dentist, “Do we need to fill this cavity?”. If these teeth will fall eventually, should baby teeth be filled?

Dental cavities

The word “deciduous” means falling off or shedding off. Hereafter, for simplicity, we refer to deciduous teeth as primary teeth. Primary teeth erupt at ages one to three years, and children typically lose them between 6 and 12. Later, permanent teeth replace primary teeth.

In 2015, estimates suggest that over 621 million children across the globe suffer from dental cavities or tooth decay. These numbers continue to increase with time. The most common risk factors for dental cavities are poor oral hygiene, eating sugar more frequently, and lack of exposure to topical sources of fluoride.

Dental cavities often cause pain. This pain negatively affects their eating (function of teeth), social interactions, and ultimately the neurodevelopment is affected. Furthermore, due to these cavities, parents may also experience financial and emotional stress.

Let’s take a deep dive into this topic to discuss primary teeth, the prognosis of caries, and fillings.

Comparing primary teeth and permanent teeth

During primary dentition, twenty teeth erupt in the upper and lower jaw. In adults, there are 32 permanent teeth. Primary teeth are replaced and additional three molars erupt on the left and right in the upper and lower jaw (i.e., 12 molars). These are called non-succedaneous teeth.

Primary teeth differ from permanent teeth in their appearance. Compared to permanent teeth, primary teeth are smaller and whiter. Their enamel, or the outermost cover, and the inner layer, dentin, are thinner. The primary molars are a flat and broad area of contact. Since the jaw has adequate space, crowding is uncommon in primary teeth.

The internal anatomy of primary teeth and permanent teeth is different. Primary teeth have large pulp chambers. Primary molar teeth have narrow and slender roots. In permanent teeth, the crown is larger than its pulp size whereas, in primary teeth, the pulp size is larger than the crown.

Why do we get cavities?

Our mouth has over 300 different species of bacteria. Most species of bacteria are not harmful to us, but some species of bacteria can cause periodontal disease and dental caries. Streptococcus mutans are commonly associated with dental caries. Some lactobacilli are also responsible for tooth decay. Species such as Treponema denticola, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans are associated with dental diseases.

Bacteria form colonies on the tooth surface, known as dental plaque. These bacteria feed on food debris or sugar in the mouth and release acids. These acids can erode minerals present on the tooth surface. Typically, saliva adds these minerals again between meals. However, when one consumes sugar frequently, the remineralization process slows down.

The process of dental decay begins with demineralization. At this stage, it is detected microscopically. Later, white spots appear on the tooth that can be detected during a clinical exam. These spots are usually subsurface lesions. If at this stage demineralization is not interrupted, then cavities are formed.

When the decayed tooth falls out

Dental problems may not end after the decayed tooth falls. It is a good idea to consult your dentist when your child gets dental cavities or experiences symptoms associated with them.

When dental cavities are left untreated, they can lead to infection and premature tooth loss. The infection can cause pain that can vary in nature. For instance, it can be acute pain, dull ache, or severe excruciating pain. It can also develop into a painful abscess. Dental pain is one of the most common causes of hospitalization in the UK.

Premature loss of primary teeth, in turn, can cause several dental issues. For instance, a loss of arch length can hurt occlusion and alignment. Occlusion refers to how the upper jaw and lower jaw meet. Alignment refers to how teeth are positioned (straight v.s. crooked) and their supporting structures.

Symptoms associated with dental cavities include:

Left untreated, it may lead to complications such as a fractured tooth, infection of the bone, or bone loss. Due to dental pain, children may have difficulty eating and disturbed sleep patterns, which may negatively impact school attendance.

Some children may need the extraction of decayed primary teeth as a part of their dental treatment plan. These children are at an increased risk of developing orthodontic problems. They may require space maintainers that can treat dental problems such as crowding, ectopic eruption, or wisdom tooth impaction.

Children commonly report a fear of dental treatments. A study reported that approximately 25% of children between ages 6-12 years have dental fears and 50% of them have a severe fear. These fears were associated with decayed permanent teeth and restored permanent teeth. In other words, the falling of a decayed tooth does not end the possibility of additional dental problems.

Filling primary teeth

To fill dental cavities, dentists can choose between non-aesthetic or aesthetic materials. Non-aesthetic materials are alloy combinations or amalgams that contain mercury. These are durable and cost-effective; however, due to concerns over mercury toxicity, these are no longer a popular choice.

Aesthetic materials such as resin composites and glass ionomer cement are popular choices these days. These are slightly expensive as compared to non-aesthetic materials, but some aesthetic materials form chemical adhesive bonds with the tooth cavity and do not require cavity pretreatment.

Although filling dental cavities in primary teeth is usually recommended, not all dental cavities need to be filled. It is a decision dentists make on a case-by-case basis. Parents and dentists can help children overcome their dental fears and seek timely help for dental cavities. Every child deserves a healthy mouth and a beautiful smile.