Dentures have never been an ideal solution to the problem of missing teeth. Although they date back to ancient Egypt, dentures have always been a compromise between having no teeth at all, and mashing your food up between two hockey pucks. The fact is, dentures offer little more than a cosmetic Band-Aid to the crippling problem of tooth loss. Traditional dentures are like offering crutches to a paraplegic; they are better than nothing, but not by much. Losing all of your teeth and replacing them with implant overdentures is a life-changing event, and you need to be able make an informed decision.
What Are My Options?
Luckily, we have come a long way since ancient times. With dental implants, it is possible to attach dentures in such a way that they stay in place permanently, just like natural teeth. If you want to learn more about dental implants, please refer to my dental implants article.
Dentures vs Overdentures
First, a bit about the terminology. In dentistry, a traditional denture is what you think of when you think about your grandparents’ dentures. Traditional dentures are a removable prosthetic that is held in by friction, suction, and/or adhesives.
Overdentures on the other hand, are attached to implants or teeth by clips or screws. Overdentures can either be permanently attached via screws, or removable with clips that snap onto implants or bars.
Implant-Supported Overdentures
Implant overdentures offer a couple of different methods of attachment. The first method is an implant-supported overdenture. With an implant-supported overdenture, the overdenture is permanently fixed to the implants. In most cases, the overdenture is screwed directly into the implants. You will be unable to remove the denture yourself, only your dentist will be able to remove it. Implant overdentures are the closest thing we have to replacing a full set of teeth.
Permanently fixed implant-supported overdentures allow you to eat just about anything you could with natural teeth. In most cases, no one will know that you even have overdentures. In fact, over time, you will probably forget you have them as well. The look, feel, and maintenance are so similar to teeth they begin to feel like your own natural teeth.
The biggest downside to implant-supported overdentures is their cost. Because these overdentures are made from expensive materials and require precision placement of the implants, they can be quite costly. A single arch can set you back between $25,000 and $45,000. A full-arch fixed denture case runs anywhere from $50,000 to $90,000.
Implant-Retained Overdentures
Similar to implant-supported overdentures, but less costly, are implant-retained overdentures. These dentures are not permanently attached to the implants, rather they snap over the implants. For implant-retained overdentures on the top, we usually place a minimum of four implants to keep them from obeying gravity. On the bottom jaw, the minimum number of implants is usually two implants. In some situations, a dental professional may place fewer implants at their discretion. More implants usually leads to better outcomes and offers redundancy in case an implant fails.
When placing implants on the bottom jaw, I typically compare the denture to a table. Imagine a table with only two legs. One side will stand on the legs, the other will lie on the floor. Dentures with two implants fit much the same way in your mouth. The implants will support the denture on the front, and the gums will support the denture on the back. Although two implants are a step up from none at all, more implants offers a more predictable and superior end result.
Bar-Retained Overdentures
Your dental professional may opt for a bar-retained overdenture. With this setup, all of the implants of the same arch connect to each other by a metal bar. The overdenture then snaps over the top of the bar. One advantage of connecting implants with a bar is the increased stability it provides to both the implants and the overdenture itself. One disadvantage is the amount of space the bar occupies, requiring a slightly larger overdenture.
Tooth-Retained Overdentures
In some cases, it is possible to use teeth, or tooth roots to retain an overdenture with the same kinds of clips used on implant-retained dentures. Usually referred to as tooth-supported overdentures, they are actually more like implant-retained overdentures than implant-supported overdentures.
For patients with healthy tooth roots and limited funds, this can be a cost-effective way to get the benefits of an implant-retained overdenture without placing any implants, especially if the patient has an existing denture they are happy with and are willing to convert it into a tooth-retained overdenture. Be aware that any tooth roots intended to be used to retain the overdenture will need to be root canal treated.
How Many Implants Will I Need?
The number of implants you require depends on numerous factors. Ultimately, the number of implants is best left to you and the dental professional who will be placing them. That said, below is some of the basic information needed to make such a decision:
Health Status
First, we take into account your overall health. Do you have any underlying health conditions that may jeopardize the implants? Diabetes, heart disease, osteoporosis and associated medications (bisphosphonates), smoking history, and other less common conditions are all contraindications for implant placement. Having one of these conditions doesn’t mean you can’t get a dental implant. However, a severe underlying health condition may mean we don’t place any implants at all.
Oral Health
One of the first things we have to consider is how you lost your teeth in the first place. If you have a history of gum disease, then we need to have a discussion about how vulnerable dental implants are to gum disease. Contrary to popular opinion, dental implants are more susceptible to the bacteria that live in gums than natural teeth are.
Many patients with extensive dental work have said to me, “let’s just pull all of my teeth and replace them with implants!” If only it were that easy… The truth is, if you lost your teeth because you had advanced gum disease, then unless we get that situation under control, you will likely end up losing your implants too.
Another important consideration when placing dental implants is whether a patient clenches and grinds their teeth. Other problem behaviors include chewing on ice or biting nails. Just like natural teeth, dental implants and their associated restorations are susceptible to damage from excessive forces.
For patients who clench and grind, I require an occlusal guard be worn during times when they are most likely to clench and grind. For some people that is while they sleep, for others it is while they exercise or commute to work. Patients with habits like nail-biting, or ice-chewing, may need behavior modification therapy.
Bone Quality
Most dental implants are placed directly into the jaw bone. Obviously the bone must be healthy enough to support the dental implant. Imagine a dental implant as a screw, and your jaw bone as being like a wall. If the wall is damaged, or the screw isn’t placed well, hanging a picture isn’t going to end well. Similarly, dental implants must be placed properly in solid bone to have a chance at long-term success.
Patients who have a long history of dentures may not have enough bone. In these cases, additional surgeries may be required to increase the amount of bone. There are a few common procedures that may allow us to create more bone for implant placement.
- Sinus lift
- Guided Bone Regeneration (GBR)
- Ridge splitting
- Mini implants
- Long implants
Sinus Lift
For patients with inadequate bone on the top jaw, we can often push the sinuses up and add some bone underneath. We can only do a sinus lift on the top jaw because there are no sinuses in the bottom jaw. After a few months, we can then place an implant into the new bone that forms. Sometimes it’s even possible to place an implant right into the bone graft and skip the waiting period entirely. Sinus lifts offer a predictable and highly successful treatment option.
Guided Bone Regeneration (GBR)
Guided Bone Regeneration can be done anywhere in the mouth. The concept is pretty simple, we open the gums, poke some holes in the bone to provoke bleeding, then add some bone graft where we need bone growth. To protect the graft, we place a protective membrane before stitching the gums back together. After a few months, we can place a dental implant in the new bone. Sometimes, if everything goes well, we can even place the implant at the same time as the graft. The success rate is higher than 90%.
Ridge Splitting
Sometimes, the bone is tall enough, but not thick enough for an implant. In those cases, one method is to split the jaw bone and then fill it up with bone graft material. Often, we can place implants at the same time and allow them to heal in place. Although this procedure sounds barbaric and painful, it is no more painful than any of the other surgical techniques described. Typically, patients can manage their pain with over-the-counter painkillers.
Mini Implants
Another option for patients with a jaw bone that is too narrow to accommodate a root-form implant, is to use mini implants. Traditional root-form implants tend to be about as wide as the tooth they are replacing. Mini implants on the other hand, are much narrower than a root-form implant, and are suitable in areas where the bone is too narrow to allow placement of a root-form implant.
Long Implants
For patients with too little bone to fit traditional root-form implants, there is another option. If your jaw bones are inadequate, we can use other bones to support an overdenture. Zygomatic and pterygoid implants are named for the bones they are placed into. Zygomatic implants are place into the cheekbone through the mouth. Pterygoid implants are placed into the bone behind your top molars. These implants are long enough to reach other bones within the skull and provide a stable, long-lasting anchor for an overdenture when shorter implants are not an option.
What Overdenture Is Right For Me?
It can be difficult to decide which overdenture solution is right for you. Rest assured that just about any implant overdenture will be an improvement over traditional dentures. When discussing implant overdentures with my own patients, we consider the following seven priorities:
- Diet
- Health
- Maintenance
- Esthetics
- Price
- Lifestyle
- Durability
Diet
Is it important that you be able to eat steak or whole apples like you did when you still had your teeth? If so, then you will want to consider implant-supported overdentures. The strength of the dentures coupled with the permanent fixation to the implants affords you the ability to eat just about anything you could with natural teeth.
Health
Do you suffer from TMJ problems or sleep apnea? Unless your dentures remain in your mouth all night, you won’t have the jaw support you need. With traditional and implant-retained overdentures, this is impossible. In order to provide the airway and jaw support you need during sleep, you will need implant-supported overdentures.
Maintenance
Don’t want to be bothered with the daily maintenance of traditional dentures? You’ll want to skip implant-retained overdentures too then. But remember, nothing is maintenance-free, not even natural teeth. You will always have to perform some level of routine care. In the case of implant-supported overdentures, the maintenance is easier than it is for traditional or implant-retained overdentures.
Esthetics
Implant-supported overdentures tend to use the highest quality materials and are therefore designed with esthetics in mind. Traditional dentures and implant-retained overdentures offer a wide variety of materials. Both can be made to look very esthetic, depending on how much you are willing to spend.
Price
Implant-supported overdentures are by far the most expensive option. However, as you can see above, they offer the best results across all categories. Implant-retained overdentures usually cost about half as much as their implant-supported cousins, but they provide a significant improvement over traditional dentures, especially on the lower jaw.
Lifestyle
Don’t want to take your dentures out every night and clean them? Then implant-supported overdentures are your best option. Both traditional and implant-retained overdentures will require thorough and frequent cleaning to avoid conditions like Denture Stomatitis.
Durability
Dental implants are susceptible to the same bacteria that cause gum disease. For this reason, implant overdentures can fall victim to implant failure due to infection of the supporting implants. This problem does not plague traditional dentures, but they can make you susceptible to fungal infections.
As the bone changes beneath your gums, a traditional denture begins to lose support. Over time, unless properly maintained, the denture may fracture due to uneven support. This is not a problem for properly fitted implant-supported overdentures because the basis of their support is bone. Furthermore, the implants help to maintain the surrounding bone, preventing further bone loss and the sunken facial profile we associate with long-term denture wearers.
The loss of a single implant can imperil an entire implant overdenture. For this reason, many dentists will place five or more implants in each jaw. If the minimum number of implants needed is four, and a dental professional places six, then the patient could lose one or two and probably still be fine.
Who Should Complete My Implant Overdentures?
Overdentures can be an extremely complex undertaking, particularly implant-supported overdentures. The level of technical skill both surgically and prosthetically is very high. Once upon a time, a surgeon or similar specialist would place the implants, and a different specialist like a prosthodontist would create the overdentures. Today, more general dentists have become “super” generalists, and they have sought extensive training in both surgical and prosthetic dentistry. These dentists are able to provide a complete surgical and restorative services which is more convenient and comfortable for the patient.
The main advantage of having the same dental professional place and restore the implants is that they control the process from start to finish. Gone are the days when the surgeon put the implants where they liked and didn’t think much about how the prosthodontist would actually attach an overdenture to them. However, with increased use of surgical guides, even specialists are placing implants exactly where the restorative dentist or prosthodontist specifies.
The disadvantage to having the same dental professional place the implants and fabricate the overdenture is one of expertise. It is certainly possible to achieve a high level of competence in both surgical and restorative dentistry, but it takes years, if not decades to master both concurrently.
As always, you will want to see examples of your dentist’s work, and ask questions about their experience and training with regard to full-mouth implant dentures. In some cases, less experienced dental professionals may be willing to perform the work at a lower price which can be an advantage if cost is a major barrier for you.
Surgical Experience
The first consideration when selecting the right dental professional for you is how much surgical experience and training they have. They don’t need to be an oral surgeon or a periodontist, but they should have placed a large number of implants before attempting an implant overdenture case. The most important predictive factor in implant success is how many implants the dental professional has placed.
Prosthetic Experience
This part is where many dentists get themselves into trouble. A poorly placed implant, or a flawed impression can lead to an inadequate overdenture. It can take a lot of troubleshooting to diagnose the problem. The earlier in the process the mistake occurs, the more its downstream effects are amplified. In some cases it can require extensive work to correct the situation.
To avoid problems with delivery of the final prosthesis, many dental professionals employ various methods to ensure things are going smoothly, below are some such examples:
3D Planning
The use of modern technologies such as intraoral scanners and Cone Beam CT (CBCT) scans has made it possible to plan and simulate implant surgery before ever touching a scalpel. These technologies also allow dental professionals and technicians to fabricate special precision surgical appliances to facilitate optimal placement of the dental implants. These surgical guides make the process of placing dental implants trivial in most cases.
Surgical Guides
Implant overdentures may require precision placement of dental implants, to achieve this, many dental professionals make use of a surgical guide. There are many types of surgical guides with varying degrees of precision. The type of guide your dental professional will use depends on the circumstances of your implant placements.
Temporary Overdenture
Even in cases where your dental professional places a fully fixed overdenture immediately, it is typically only a temporary prosthesis. The first overdenture is usually acrylic, the same material a we use to make traditional dentures. This affords you the opportunity to get used to the fit and feel of the overdenture, and also makes it easy for your dental professional to make minor adjustments over time based on your feedback. After a period of weeks or months, we can then base the final overdenture design off of the temporary.
In cases where the temporary overdenture doesn’t attach to the recently placed implants, you can expect to wear a traditional denture while the implants heal in place. After a period of weeks or months, your dental professional will either convert your existing denture into an implant-retained overdenture, or they will deliver a new implant-retained overdenture.
Implant Verification Jig
After we take the final impressions of your implants, there can be distortion of the impression material, or the models we fabricate to create our final overdenture. To verify that the model matches your mouth, we will often make use of an implant verification jig. These verification jigs are a way for us to check our work and ensure that the model matches your mouth before sending everything to the lab for final fabrication of the overdentures.
Should I Get An Implant Overdenture?
Of course the decision to get an implant overdenture ultimately rests with you. Hopefully I have answered many of the questions you may have had about implant overdentures above. If you are still unsure about whether you could benefit from an implant overdenture, consider the following questions:
- Are you unhappy with your current dentures?
- Are you missing multiple teeth, or will you need to have multiple teeth pulled in the near future?
- Do you have advanced gum disease and loose teeth with a poor prognosis?
- Do you have multiple failing restorations and teeth with a questionable prognosis?
If you answered yes to any of the above questions, then you could be a good candidate for implant overdentures. If you have any questions or comments, please leave a comment below.