Dentistry for the Entire Family in Fridley MN


What does a cavity look like?

Tooth with cavityGenerally speaking, a dental cavity (also called tooth decay) can range in color from white to brown and eventually black as the cavity continues to grow.
In its early stages, the variation in color looks similar to stains that form on the outer surfaces of teeth for people who enjoy drinking coffee and/or tea. (Photo source: Wikipedia)
The shape of a cavity is organic and changes as the cavity grows in width and depth.
As this happens, the frequency and duration of symptoms will continue to increase as the decay or cavity grows in size and depth.
Left untreated, tooth decay will eventually impact the nerve of the tooth resulting in a painful tooth infection that requires an emergency visit to your dentist.

What does a cavity feel like?

You might be surprised to learn that a cavity is oftentimes asymptomatic until the cavity grows in size and enters the middle layer of the tooth called the dentin.
The dentin layer of the tooth contains nerve endings that when activated (for example: chewing something sweet) will result in a symptom that a person can feel. Symptoms may include chewing and/or temperature sensitivity, or even a twinge when eating something sweet.
Potential signs/symptoms that you may have tooth decay include:

  • Temperature sensitive to hot/cold
  • Chewing sensitivity
  • Spontaneous pain without known reason
  • Bad breath
  • Visible hole in tooth
  • Broken/chipped tooth
  • Brown, black, or white staining

Decayed tooth

Diagram of tooth with a cavityMost often, decay begins at the base of pits and grooves on the chewing surfaces of molars where it is difficult for the bristles of a toothbrush to effectively reach and remove bacteria and trapped food particles.
Looking in the mirror, we won’t likely see or suspect a cavity until we see a visible color change what will look similar to coffee/tea stain. The difference between coffee/tea stain and tooth decay is that staining from drinking coffee or tea is extrinsic and can be removed with toothbrushing. Whereas, tooth decay is a bacterial infection and can’t be brushed away.
As stated earlier, the color of the decay will often change color as it grows, from light yellow to brown, and from brown to black. This process may be gradual or acute. Symptoms will increase as cavity increases in size and grows closer to the nerve of the tooth.

Baby bottle tooth decay

Baby-bottle-tooth-decay-close-upBaby bottle tooth decay (caries) is caused by frequent, prolonged exposure to beverages containing acidic and/or sugar.
In many cases, research has shown that parents of infants and toddlers with baby bottle caries frequently had put their babies to bed with a bottle filled with a liquid containing sugar.
Sugar is acidic. Frequent exposures weaken tooth enamel (outermost layer of tooth). Eventually a cavity will begin to develop along with symptoms.
For infants, this may include irritability, diarrhea, and/or potential refusal of their bottle if it contains a liquid containing sugar.
Sugar + tooth decay = discomfort/pain
If your baby insists on falling asleep with a bottle, only fill the bottle with water. If this does not help, we encourage you to talk to your child’s pediatrician for more information.


Child tooth decay

Until the time that your child can tie their shoes unassisted, they do not have the dexterity to effectively brush and floss their teeth unsupervised.
Picture of child with cavityParents and caregivers need to follow up after their child brushes their teeth to brush and floss missed and difficult to reach areas to help lower the risk of developing tooth decay.
Tooth decay is the most prevalent chronic disease in both children and adults (National Institute of Health).
Child tooth decay can impact developing permanent teeth.
Untreated tooth decay can also impact your child’s ability to focus and learn in school. It is difficult to concentrate on homework if your child has a toothache.
It is important for parents to know that child tooth decay does not look any different than a cavity in an adult, permanent tooth.
If your child’s dentist diagnoses a cavity, it is important that the decay is removed and the tooth is restored as soon as possible in order to help protect the developing permanent tooth underneath the baby tooth.
It is a myth that baby teeth with cavities do not have to be restored because they will eventually fall out anyway. This is only true if the permanent tooth is already visible and growing in. Otherwise, decayed baby teeth will need to be restored.


Wisdom tooth decay

dental x ray showing wisdom teeth at angleWisdom teeth or third molars are often at high risk for developing tooth decay. Why? Their location—way back in the mouth, makes it difficult for most people to reach and effectively clean around them.
Wisdom teeth are also notoriously known for coming in at an angle (pictured right) which can be problematic for adjacent teeth.
Many times, wisdom teeth may only partially grow in due to the limited space and proximity to the jawbone. There may not simply enough room to enable them to fully form and/or erupt from underneath the gum tissue.
Decayed wisdom teeth do not look any different than other teeth with decay. The primary exception to restoring a decayed wisdom tooth is that they are difficult at best and sometimes not possible for even the most skilled dentist to be able to restore because of space constraints for hands, dental tools, etc.
And for the patient, they may not be able to open wide (due to human anatomy) enough to facilitate the removal and restoration of the decayed tooth. It is for these reasons, many people undergo oral surgery to have their wisdom teeth removed by extraction.
Often the question is asked, “Do I have to have my wisdom tooth removed? If so, when?”
Great question! For most people, wisdom teeth become visible inside the mouth sometime between the ages of 17-28.
Beginning at age 18, the dentist will recommend for you to have a full-mouth set of x rays or a panorex film. Upon reviewing the images taken, your dentist will be able to show and discuss with you, if and when, you may need to consider having your wisdom teeth extracted.


Tooth decay at gum line

Another name for tooth decay at the gumline is root surface caries. Tooth decay at the gum line is often caused from allowing plaque to remain along the edge where the tooth and gum meet.
Picture of tooth cavity at gum lineWhen a cavity along the gum line forms, the cavity can be on both the enamel and the root surface of a tooth.
The root surface of a tooth is less dense and is porous in comparison to the top portion of a tooth that has a layer of hard, protective, enamel. This anatomical difference means that any exposed root surfaces are at very high risk for developing tooth decay.
Tooth decay at or near the gumline often appears dark yellow, brown, and/or black (pictured right) and are often sensitive to temperature.
If you suspect you might have a cavity forming, it is best to schedule an appointment with your dentist as soon as possible.
Left untreated, decay on these surfaces can require extensive treatment to restore. (Photo Source:
Prevention tip. If your dentist determines that you are at high risk for developing root caries, your dentist may prescribe a prescription strength fluoride that you brush on daily to help strengthen exposed root surfaces from developing tooth decay.

Cavity between teeth

Cavities between teeth (pictured right) may develop if a person does not effectively remove trapped plaque and food debris from the side surfaces of teeth.
Because these surfaces are often just out of reach from toothbrush bristles, another cleaning device is required. Most popular options are string floss, Waterpik, and/or flexible toothpick-like bristle cleaners.
Picture of dental cavity between teethMost often, cavities that develop between teeth are often not visible with the naked eye. Therefore your dentist will request his/her assistant or hygienist to take a series of x rays called bitewings or decay detecting films to check for any developing cavities between your teeth.


How many xrays are necessary to check for cavities? It largely depends upon how many teeth are present. For adults, this may be 2-3 per side and for kids, often 1-2 per side.


What does a cavity look like on an x ray? Because x rays are required to detect developing cavities between teeth, cavities on x rays will range in color from dark gray-black. Decayed areas will have an organic shape.


Does the xray show how deep a cavity is? Yes and no. Cavity checking x rays are two-dimensional meaning they show the dentist the size but not necessarily the exact depth of the decay. For instance, the x ray pictured right shows the decay is quite large and appears to be quite close in proximity to the nerve.
Just how close? The dentist will not know for sure until decay is removed. It is highly likely this dentist told this patient that they anticipate the dental restoration will be large and likely will be temperature sensitive to chewing and temperature because of the proximity of the decay is to the nerve of the tooth.


How often does a person need decay detecting cavity pictures? It largely depends upon an individual’s risk factors for decay including: home care, diet, general health, and frequency of preventive care visits. Your dentist will discuss your risk factors and will discuss frequency with you during your visit.


Black spot on tooth

Black spot on toothIf you see a black spot on one of your teeth, don’t panic and assume you have a cavity.
The chewing surface anatomy of molar teeth include deep pits and fissures (grooves) that are easily stained if you regularly drink coffee, tea, or eat certain foods.
Stained areas are at higher risk for decay. Why? Because the pits and grooves can easily trap food particles and sugars from beverages and they’re difficult to clean even with an electric toothbrush. (Photo Source:


Cavity around existing dental restoration

A cavity that develops around an existing dental filling is often called recurrent or secondary decay.
Recurrent decay most often develops around restore teeth whose margins have begun to separate or pull away from the adjacent tooth structure. Often, this happens slowly over the course of several years.
Picture of cavity around dental fillingUnfortunately, no dental restoration lasts forever.
Eventually a space will take shape which will attract and trap bacterial plaque. As this space increases in depth and width, brute chewing forces will make the surrounding tooth structure increasingly more vulnerable to breaking and/or cracking.
For this reason, if you have existing dental restoration, your dentist will likely proactively recommend a more frequent interval (annually) to take decay detecting films in order to monitor and help prevent you from accidentally breaking and/or cracking one of your teeth.
Pictured right. On the tooth showing the silver filling, there is a slight gap forming along the edge of the filling and the tooth. This is where bacteria can sneak in and create a cavity inside the tooth between the tooth structure and the filling.


They say “a picture is worth a thousand words”. I hope this article and corresponding pictures featured have helped you to know what tooth decay looks like as well as all the different areas where tooth decay can develop. At this point, you might still have a few lingering questions regarding tooth decay including:

  • Can you stop a cavity from growing?
  • Can you cure tooth decay?
  • What are some home remedies to prevent cavities?

Frequently asked questions

Can you stop a cavity from growing?

Tooth decay can be stopped in its earliest stages of decay provided decay has not extended beyond the enamel layer of the tooth. Enamel is the outermost layer of a tooth and is the only layer of tooth that has the ability to repair itself by using minerals from saliva and fluoride from toothpaste Source: National Institute of Health

Can you cure tooth decay?

There is no cure for tooth decay but it can be prevented by following an effective, daily oral care regimen. A regimen that includes brushing for two-minutes with a fluoridated toothpaste every morning and evening, and flossing between teeth daily.

What are some home remedies to prevent cavities?

Home-remedies to prevent cavitiesThe best home remedies to prevent cavities include:

  • Avoiding processed food and drinks containing sugar.

  • Brushing two times daily and flossing every evening.

  • Having your teeth professionally cleaned and examined every six months.

  • Drinking plenty of water throughout each day to stay hydrated and prevents from having a dry mouth.

  • Using an anticavity rinse daily to help strengthen outer surfaces of teeth from demineralization.


Do you think you might have a cavity?

If so, don’t wait, call Dentistry for the Entire Family at 763-586-9988 to schedule an appointment. Or you can request an appointment via email.



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Dentistry For the Entire Family

1099 East Moore Lake Drive

Fridley, MN 55432

Phone (763) 586-9988

Fax (763) 586-9977

Email Us

Hours of Operation

Monday 7:30am - 5:00pm

Tuesday 7:30am - 5:00pm

Wednesday 7:30am - 8:00pm

Thursday 7:30am - 5:00pm

Friday 7:30am - 4:30pm

Saturday Closed

Sunday Closed