Tooth decay and chipping or cracking can be corrected in a variety of different ways, among them inlays and onlays. Understanding what inlays and onlays are, how to distinguish them from each other and from other dental appliances, and knowing when each type of tooth restoration method is most appropriate are all key to taking good care of your teeth for life.

At The Downey Dentist, we are committed to providing you with the full range of options for tooth repair and restoration available in modern dentistry. We have deep experience, extensive formal training, and all the latest dental tools, materials, and techniques at our disposal - and we use it all in your best interests to bring back your natural smile.

To learn more about inlays and onlays, continue reading below. For a free dental consultation or to schedule your first appointment to meet with us in person, do not hesitate to contact us today by calling 562-746-0350!

We are located in Downey, California from which we continue to serve the people of Southern California by meeting their need for comprehensive, family dental care.

What Are “Inlays” And “Onlays?”

A simple filling is often sufficient to restore the damage done by tooth decay, but this is not always the case. First of all, if tooth decay has gone too far, a root canal may be necessary. And when the damage is very extensive on the top of a tooth - and includes fissures or extreme wearing of crown enamel, a full dental crown (overlay) may be the best option.

But there are situations in between these two extremes, where an inlay or an onlay is going to be your most appropriate dental appliance. These twin dental appliances are known as “indirect” fillings as opposed to “direct” fillings that involve boring a hole into a tooth to remove all decayed tooth tissue and then filling it in up to the tooth’s surface. With indirect fillings, the tooth restoration material lays on top of the tooth’s natural crown, either residing in the “valleys” between the pointy “cusps” of a tooth or also covering one or more such cusp.

When a cusp is covered, it is considered an “onlay,” while a purely “between the cusps” type of indirect filling is called an “inlay.” Almost always, inlays and onlays are used only on the back teeth, meaning molars or premolars.

In the past, inlays and onlays were almost always made of gold, but today, they come in a variety of materials - just like modern dental crowns and fillings. Many of them are made to mimic the look and feel of a natural tooth so that they hardly noticeable to those who don’t already know they are there. A variety of different dental sealants and other bonding methods are used to permanently and firmly attach indirect fillings to the crown surface. A tooth with an inlay or onlay will actually be stronger, in many cases, than an “ordinary” tooth - these dental appliances DO NOT WEAKEN your teeth.

Inlays VS Dental Fillings

Hypothetically, inlays and fillings are not strictly distinct, for they both are used fill in some kind of cavity. And both involve removal of at least some tooth tissue before filling in the hollowed out space. But there are other factors that tend to distinguish inlays from ordinary dental fillings.

First of all, inlays are used to fill cavities that are relatively larger in size. Secondly, most fillings are composite or amalgam, while most inlays are gold or ceramic - but this is not a hard and fast rule. Third, an inlay is made of a single piece that is prefabricated in a dental laboratory or made in-office at the time of the dental procedure. Fillings consist simply of materials that are stuffed into the cavity hole and allowed to dry and form into a solid mass.

An inlay must be formed to precisely match the contours of the area of the tooth it will rest upon. Modern cameras and fabrication methods make this possible. It is crucial to have a perfect fit so no germs or food particles can get between the inlay and tooth surface and ultimately inside of the tooth to create a new cavity.

Inlays tend to cost more than fillings, and many dental insurance policies won’t cover the extra cost. However, inlays are superior in that they do not contract like ordinary fillings do and have much less chance of failing or developing a gap later on. Inlays are tougher and more durable than most fillings and, thus, are considered by many to be worth a little extra cost in the right situation.

Onlays VS Dental Crowns

When the part of your tooth crown to be restored is larger even than what an inlay would cover, much less a filling, and also restores one or more dental cusps on a molar or premolar, it is called an onlay. Any cavity must still be removed before applying the onlay, so there is a removal of at least some tooth material and a filling in of the hole. But the onlay, like an inlay, is of a single prefabricated piece, not of loose filling material that is simply pressed into the hole.

Dental crowns are similar to onlays in many ways. Both must be made to exactly fit the tooth onto which they will be placed. Both are premade in a dental lab or on-site during a dental visit. Both are used for major tooth damage that is focused in the are of the natural crown. However, crowns are distinguished from onlays in that crowns cover the entirety of the tooth’s biting surface, while onlays do not. Crowns may also cover much or all of the tooth above the gum line.

Onlays cost a little less than do dental crowns, and therefore, they are preferred by both patients and dental insurance companies where they are the most effective solution. But you need an especially skilled dentist to properly apply an onlay. Onlays are more difficult to place than crowns since they do not cover the whole tooth and have to line up perfectly to prevent seepage.

When To Opt For Inlays & Onlays

To sum up much of the above information, we can now look at when it makes sense to get an inlay or onlay as opposed to other dental care and what are the benefits of inlays and onlays.

For inlays, you would use them whenever a tooth fracture, cavity, or chip on the upper tooth surface is too large for a filling and does not affect any of your cusps (on your molars and premolars.) To use an oversized dental filling instead of an inlay could weaken the tooth structure and risk breakage and tooth loss down the road.

Onlays are preferred when the cusp is damaged, and yet, the damage is not sufficiently widespread to merit installing a full dental crown. A crown requires removal of more tooth material to support it properly, and you want to retain as much of your natural tooth as possible.

Both inlays and onlays are stronger and more durable than are fillings. Inlays are more expensive than fillings, while onlays are less expensive than crowns. Inlays and onlays can last as long as 30 years due to the hard-wearing materials from which they are made. They result in approximately a 75% strengthening of a tooth, while fillings may sometimes actually weaken a tooth to a degree. All in all, inlays and onlays help extend tooth life and avoid the need for additional treatments in the future.

Many times, an inlay or onlay will be resorted to when you need to replace an old filling that is giving out. You can opt for simply redoing the old filling with a new one, but oftentimes, superior, long-lasting results are achieved by using inlays/onlays.

The Inlay/Onlay Placement Process

The process of getting an inlay or onlay installed is basically the same, and it’s not much different than having a dental crown attached. The main difference is that there is less drilling needed and less loss of your natural tooth with inlays and onlays versus with dental crowns. There is not much reshaping of the tooth with inlays/onlays because they generally conform to the contours of your natural crown.

You normally have to go through a two-step process to have an inlay or onlay placed. During the first appointment, your dentist will numb the tooth and surrounding area with a local anesthetic. Next, the decayed part of the tooth (if any) is removed through dental drilling and by cleaning out the hole thoroughly. To the extent the tooth needs to be shaped to receive the inlay or onlay, this is done also at this stage.

Next, after your tooth has been fully prepared for the inlay/onlay, dental putty is applied to make an impression of the area. Sometimes, modern dentistry will use digital images to collect this data instead. A tooth-colored ceramic, resin, or other material is used to form the inlay or onlay to the exact needed dimensions. This can be done in-office with the most up to date methods, but sometimes, it may still be preferable to send the instructions to the dental lab. A temporary filling or crown will usually be placed over the tooth while you await the inlay or onlay to come from the lab.

During the second session, the temporary filling/crown is removed and a resin or other hardening agent is applied to the tooth before placing the inlay or onlay over it. Permanent dental cement will create a strong, durable bond. You can use them just like fully natural teeth and they require no more than ordinary oral care (brushing, flossing, and antiseptic mouth rinse.) The final touch during the second visit is to polish the finish of the inlay or onlay to ensure it will look its very best.

Each visit for receiving dental inlays and onlays takes only around an hour (more if multiple teeth are being worked on.) There is a little discomfort immediately after the operation, for it takes a couple of days for the area around the tooth to fully heal from any soreness, but there are over the counter painkillers that can help. The tooth with the inlay or onlay may feel “funny” at first, but soon enough, you won’t even know it’s there.

Materials Used For Inlays & Onlays

The most traditional material to use for an inlay or onlay is gold. However, fewer and fewer patients opt for gold these days, favoring instead materials that blend in with the natural tooth. Gold is good because it is strong and “ductile,” which allows it to withstand the pressures of chewing and talking. Therefore, with gold, the inlay or onlay can be thinner and require less tooth material to be removed. As only back teeth get inlays/onlays anyway, many are willing to put up with the aesthetic problem of gold since back teeth aren’t much seen anyway.

A second option is ceramic. Ceramic looks more like natural tooth enamel than gold or amalgam, but due to its lesser strength and ductility compared to gold, you have to lay it down thicker and may need to reinforce it with metal in some cases. Metal-ceramic inlays and onlays have a lower fracturing rate than pure ceramic and have greater strength and durability as well.

Composite resin is another option for inlays and onlays. Composites vary in composition and in the size or the filler particulates. This options offers excellent aesthetics and even allows exact matching of shades. You get an even closer match to the tooth color than you would get with ceramic. Also, composites are easier to repair or adjust down the road as compared to ceramic. Composites required a light-cured bonding agent and require more dental skill than other options - so be sure you choose a dentist (like The Downey Dentist) who has well-honed skills in this area.

Dental Sealant Options For Inlays & Onlays

To seal most inlays and onlays into place, adhesives called “luting agents” are used. This dental cement can be applied to both the inlay/only and to the tooth itself before joining the two together. As soon as the inlay/onlay is put into position, the viscosity level of the sealing agent rapidly decreases, which greatly reduces the odds of the inlay or onlay ever cracking or breaking.

The best luting agents have what is called a “low modulus.” This means that they absorb most of the pressure instead of transferring it to other parts of the tooth structure. This type of dental cement is more flexible and able to withstand higher pressures without significant risk of failure of the dental appliance.

In some cases, little to no dental cement is needed if the inlay shape is just right and tightly fits into the inter-cusp areas of the crown. But in most cases, you will want to use plenty of high-quality dental cement of the luting type. With the bonding of ceramic inlays and onlays (and ceramic-metal), chemically cured resins are usually best. But with composite inlays and onlays, due to “polymerization shrinkage,” temperature, light, and pressure must be used to ensure the securest possible bond.

How Much Do Dental Inlays & Onlays Cost?

Inlays and onlays are improving year by year, with materials getting stronger and more durable and aesthetics becoming ever more closer mimics of natural teeth. It takes special dental skills and equipment to get well-done inlays and onlays, and not every dentist can do it. We at The Downey Dentist provide you with full inlay and onlay options in keeping with our goal to be your one-stop-shop family dentist.

The cost of inlays and onlays varies greatly. Onlays tend to cost a little more since they are larger and more involved, but the overall range is from $250 to $1,500 per unit. Costs vary greatly from region to region and based on which types of materials and sealants you choose to use. The size of the inlay or onlay also affects the price. If you get the inlay/only fabricated in-office instead of waiting for the lab work to be finished, that could also cost a little bit more. Finally, the location of the teeth being worked on - back teeth are more difficult to access, and the amount of work needed to prepare the tooth for the indirect filling also come into play.

We at The Downey Dentist always give your competitive, upfront pricing and accept most forms of dental insurance. We may be able to help you get a payment plan or financing to enable the procedure. Some dental plans count inlays and onlays in the same “basic” category as fillings and cover them for 80%, while other plans may put them under “major procedures” and cover only 50%.

Find A Top-tier Inlay & Onlay Dentist Near Me!

At The Downey Dentist, your first exam is free (for new patients)! Also free is our over-the-phone consultation concerning your dental needs. Do not hesitate to call us today at 562-746-0350.

We are located in Downey, CA, and serve the whole Los Angeles Area. We have the highest standards of customer service and live on the cutting edge of modern dentistry.