Dental fillings are one of the most routine procedures offered in family dental practices. Depending on the size of the cavity, a typical filling can be completed within about an hour. Different types of fillings may require more time to prepare and place, but the procedure is fairly comfortable with the help of local anaesthetic (numbing medication) and additional sedation options as needed.
What is a Filling?
A dental filling is the first-tier restoration used by dentists to repair an area of active tooth decay (cavity.) The filling is shaped into a hole or ‘cavity’ in a tooth after removing the diseased tooth structures. Your dentist will shape the filling so that it fills in the void and rebuilds the overall shape of the tooth in that space.
By placing a dental filling, your dentist can help stop the spread of tooth decay and preserve as much healthy tooth structure as possible. However, fillings can only be used when there is still enough healthy tooth structure to hold the filling in place. Fillings go inside a tooth when the majority of the tooth as a whole is still intact. If the tooth is significantly damaged, a full-coverage restoration such as a crown is used rather than a smaller filling; unlike fillings, crowns cover the entire tooth and protect it from the outside.
Types of Fillings
Composite Resin (White) Fillings — Tooth-coloured dental fillings are made from materials that blend in with the overall appearance of your tooth. Since they come in various shades, the composite blends in with the surrounding enamel, making white fillings practically invisible. Additionally, the resin is capable of bonding closely with the porous structure of tooth enamel, making it easier to bond into unconventional spaces that wouldn’t support a silver filling. This unique characteristic ensures a minimally invasive approach to care (because more tooth structure is preserved) and is the most conservative treatment for someone with a small cavity. On average, white fillings are placed in under an hour.
Amalgam (Silver) Fillings — Before the development of tooth-coloured resin materials, most dental fillings were made from a metal alloy containing a combination of materials such as tin, silver, and mercury. While affordable, silver fillings do not bond to teeth like composite resin restorations, and as such, they require additional tooth structure to be cut away to wedge them into place. This one characteristic makes them more invasive than composite fillings. But they have one advantage; since they can be placed in a wet environment, amalgam fillings can still be performed when the area is exposed to a salivary duct or the patient has trouble sitting still. Unfortunately, there is widespread concern among patients and dental professionals regarding the mercury content in these fillings, not to mention their aesthetic challenges. As such, most dentists refrain from using amalgam as frequently as they did in years past. While amalgam fillings only require about an hour-long appointment to complete, it may take several hours for the metal alloy to harden.
Lab-made Fillings/Inlays and Onlays — For teeth with larger areas of structural damage, additional reinforcement is needed. Lab-made inlays and onlays—also called ‘indirect fillings’ provide extra durability for teeth that cannot support a traditional filling. However, they do not cover the entire tooth the way a crown does, but rather 2/3 to 3/4 of it. Like crowns, these indirect restorations are crafted in a lab from materials like porcelain or gold. Because of the design process, inlays and onlays typically require at least two appointments to complete. If your dentist has in-house milling equipment, ceramic inlays and onlays can be completed in one much longer appointment. While they offer additional protection and are more conservative than crowns, indirect fillings tend to be more expensive than traditional dental fillings due to the manufacturing process involved. Like white fillings, these porcelain or ceramic restorations blend in with the colour of the surrounding tooth structure.
Do I Need a Filling?
One of the most common misconceptions about dental fillings is that if your tooth doesn’t hurt, you don’t need to fix it. Unfortunately, tooth decay isn’t always easy to detect. While there are certain warning signs—such as sensitivity to pressure, sweet flavours, food catching between teeth, or dark enamel—cavities may exist between teeth or under the biting surfaces without you being able to see or feel them. In some cases, decay can become so advanced that the tooth begins to abscess and may still not exhibit signs of pain.
Fortunately, you can still treat cavities while they are small and asymptomatic. The best way to identify active tooth decay is by examining your teeth and taking periodic digital X-rays during routine dental checkups. These images allow your dentist to assess the entire tooth structure, including areas that are not visible to the naked eye. With routine screenings, cavities can be detected extremely early, usually well before symptoms of pain or sensitivity develop.
Early diagnosis and early intervention also mean that smaller, more conservative fillings can be used. Waiting until symptoms form or you can visibly see a cavity may result in the need for more complex and expensive treatments due to the extent of tooth damage. Treating your cavity early with a small filling will preserve more tooth enamel, help prevent emergencies, and cost less to repair than a crown or root canal.
The Tooth Filling Process
Most dental fillings are usually scheduled for a later date, after your exam and X-rays. However, if you are seeing a dentist for tooth pain, and their schedule allows, they may be able to complete your dental filling on the same day. While the average dental filling procedure is usually scheduled for anywhere from 45-60 minutes, much of that time is spent preparing you for the filling rather than the actual time required to place it.
First, your dentist or the assistant will rub a topical numbing gel on the gum tissues where the anaesthetic is to be injected. This will usually take at least a few minutes to begin working. Once it takes effect, the dentist will inject a local anaesthetic (numbing medication) into the area where the nerve supplies sensation to your tooth. Most people describe this as a small bee sting, but some people may not feel the injection at all.
After approximately 5-10 minutes, the anaesthesia will be in full effect, and the affected tooth should feel completely numb. In some cases, more anaesthetic is added to ensure you don’t feel anything. Always let your dentist know if your tooth is sensitive so that they can add medication when needed.
Some teeth will require special devices or barriers placed around them to isolate the tooth during the procedure. These aids also help with shaping the margins of the filling between the teeth to keep those surfaces smooth and prevent complications. This step usually takes less than 5 minutes to complete.
Next, the dentist will spend about 10-15 minutes cleaning away the damaged or decaying tooth structures. This time can be much shorter or even a little longer, depending on the size of the cavity. Your dentist will use an extremely fine-tipped instrument called a bur, which will remove the damaged enamel or dentin and be used to smooth the inner structure so that it is ready to receive the filling.
Finally, your dentist will condition the tooth and place the filling material inside it. Next, they will shape it so that the outer surfaces of the filling restore the natural tooth shape and size. Resin fillings are cured with a light and then polished for a smooth finish.
Although your procedure will be fairly short and simple, you can expect the numbing medication to last for at least a few hours afterwards. Most people are able to resume their normal activities unless they receive a stronger sedative than laughing gas, in which case they will need someone to drive them home and stay with them for the rest of the day.
Does Getting a Filling Hurt?
Since your tooth will be thoroughly anesthetised, you should not feel any pain or discomfort during your filling appointment. You may, however, feel some pressure when the tooth is being cleaned and reshaped. If you experience any pain whatsoever, be sure to let your dentist know. They can apply additional numbing medication to ensure the tooth is thoroughly ‘deadened.’
If you have hypersensitive teeth, a sensitive gag reflex, or additional concerns about discomfort during your dental filling, you may want to speak to your dentist about sedation during your appointment. Light sedation, such as nitrous oxide or laughing gas, can help you feel more relaxed and less sensitive to stimuli during the appointment. Deeper sedation, like oral conscious sedation, may be recommended if you have severe dental phobia or require longer, more extensive restorative treatments.
Additionally, it can be helpful to listen to music during your procedure. Consider bringing earbuds and your phone to listen to a playlist, podcast, or meditation app during your appointment.
The good news is that most people can get a dental filling without experiencing much—if any—discomfort throughout the appointment process.
How Long Do Fillings Last?
Multiple factors can affect the average lifespan of dental fillings. The most important is good oral hygiene, including daily brushing and flossing, as well as regular dental checkups. These steps will help ensure a clean surface around the margins of your filling, lowering your risk of recurrent decay around your restoration.
Second, be sure to monitor your diet and limit your intake of sweetened or artificially sweetened beverages and processed carbohydrates. Both natural and artificial sugars, when consumed frequently, can lead to enamel erosion and acidic plaque, causing new areas of tooth decay to form. Open margins around older fillings or silver restorations may lead to newer and larger areas of decay, so be sure to have your teeth examined routinely.
When cared for properly, most dental fillings can last at least 7-10 years in a typical scenario. It’s not unheard of for some fillings to last as long as 20 years. By seeing your dentist at regular intervals, they can evaluate your existing dental work and intercept issues earlier when they’re less noticeable, helping to prolong the average lifespan of your restoration and other dental work you may have.
Again, one of the added benefits of white composite fillings is that, because of their smaller size, they can usually be replaced with a new filling once they wear out. Whereas larger silver fillings almost always require a crown once those restorations have reached the end of their lifespan.
How Long Should a Tooth Hurt After a Filling?
The closer a cavity is to the nerve of your tooth, the more likely you are to experience sensitivity after a filling is placed. Typically, the nerve of your tooth will respond or ‘pull back’ from the treated area after a filling is placed. As such, it may take a few days or weeks to adjust to cold or warm temperatures when you’re eating and drinking.
Additionally, you might experience soreness or discomfort where the local anaesthetic was injected, similar to what you might feel after getting a shot at the doctor’s office. As the numbing wears off, the injection site may feel sore. Thankfully, this discomfort is typically minimal and goes away within a few days.
To manage post-operative discomfort after a filling, it’s recommended that you take an anti-inflammatory medication such as ibuprofen as directed. Rinsing with warm salt water can also ease any irritation at the injection site. However, if you are experiencing severe or persistent pain, it hurts to bite down, or there is discomfort that lasts for more than a few days, be sure to reach out to your dentist.
Dental fillings are effective treatments for tooth decay and are appropriate for patients of all ages. Ideally, cavities are caught when they are just beginning to form so that a small filling can be used to repair the tooth rather than waiting until the decay is painful and more extensive to repair. Today, most dentists will use composite white fillings because of their minimally invasive characteristics and ability to blend in with your smile. On average, white fillings only require about an hour-long appointment to complete and typically last a decade or longer when cared for properly. By practising good oral hygiene and seeing your dentist regularly, you can prolong your existing dental restorations and limit your risk of new cavities in the future. When was the last time you scheduled a dental exam?
