Replacing Missing Teeth
Missing teeth can be replaced in a variety of ways.
You may be a candidate for any one or all of them, depending on the circumstances. Implants are becoming the treatment of choice for a number of reasons. Most significant among these is the expected longevity, strength and stability offered by current implant treatment, as well as the predictability of implant treatment with current technologies. Listed below are common treatment options for missing teeth.
Options which do not come out of your mouth:
If you are a candidate for an implant, it is by far usually the most predictable and long-lasting replacement. The strength resembles your natural tooth and most people can eat the foods they used to eat. Implants are also the replacement which most closely duplicates your natural tooth. Implants are the only replacement which do not destroy any part of an existing tooth, or place undue stress on remaining teeth.
Throughout history, options for teeth replacement have changed and improved: from dentures, to partial dentures, to bridges, to implants. For those who are not candidates for implant therapy, these other options still exist.
An implant is also versatile. It can be used to replace one tooth, or multiple teeth. Implant bridges can be used to replace multiple teeth in a single area. Implants can be used to retain dentures by clicking or locking into the implant(s). Once the implant is in place, the top (abutment) of the implant can be changed to allow for changing options as the need arises. For example, if you have implants replacing one or multiple teeth, and eventually need a denture, the same implants can be modified and used to hold the denture. This is not possible with any other option for replacement.
Teeth can also be replaced with a fixed bridge if there are teeth in the area that are adequate in number and sufficiently healthy and strong to support the artificial teeth. In order to fabricate a bridge, the adjacent teeth are prepared by reducing their size (or cut down) to remove all the enamel, making room for the prosthetic tooth restoration. A prosthetic tooth (or teeth) can be suspended between adjacent teeth in this way to provide a functional and cosmetic replacement for the missing tooth.
The limitation of this form of treatment has to do with the irreversible preparation of the adjacent (abutment) teeth for support. This exposes them to the risk of trauma to their nerves, raising the risk of requiring root canal treatment. Long-term, fixed bridges between natural teeth have an average life expectancy of 7-10 years before requiring replacement. Most bridges need replacement because people form cavities due to ineffective cleaning in such a difficult area, not because the bridge itself has any problems. Replacement of fixed bridges often entails further treatment as the abutment or supporting teeth have been further compromised over time by this advancing dental disease (such as cavities or periodontal bone loss).
Options which are removable:
Removable partial or full dentures can replace a single missing tooth, several teeth, or all of the teeth in your upper and/or lower jaw. Dentures rely on support by the other teeth in that jaw (for partial dentures) and from mechanical support by the remaining ridge of gum and underlying bone. This support places stresses on remaining teeth which they are not meant to handle (partial dentures), or destroys the underlying bone (full dentures.) Without bone, retention and support are lost; this is why often the first denture is remembered as the best. And once this bone is lost, it is very difficult, if not impossible, to predictably regain what you once had. Maxillary (upper jaw) full dentures also may be helped by suction between the denture and the underlying gum of your palate (roof of mouth).
Dentures are usually about 6% as effective as your natural teeth. They are better than no teeth, but they are not a true replacement.
Why should I replace a tooth/teeth?
Reasons for replacing a missing tooth (or teeth) vary and should be weighed against the risks of leaving the space, as well as resultant changes that may take place in the rest of your dentition.
If you are missing a couple of teeth:
Loss of one or two teeth in a segment of your mouth can lead to drifting of neighboring teeth, whereby the adjacent teeth lean over into the vacant space where the teeth have been lost. Similarly, loss of a tooth or teeth can lead to shifting of opposing teeth as they drift down into the open space (super-erupt).
In general, our teeth have a constant tendency to move both towards the front of our mouths and towards the opposing jaw, unless they are stopped by something in their way, usually the adjacent or opposing teeth. Loss of teeth allows this to proceed in a pathologic way. As teeth drift, they create discrepancies in the height and contours of the gum tissue that predispose adjacent teeth to periodontal disease progression and/or dental decay from accumulation of food and plaque and difficulty in cleaning these areas from “piled-up” gum tissue. Drifting teeth can also adversely affect the occlusion (bite), as well as cosmetics of your face and smile.
If you are missing a few more teeth:
People adapt, and many are able to function with missing, or even no teeth. This does not mean that this is healthy. It is a fact that as we age our digestive tract slows down, the muscles which move the food along the digestive tract do not function as well. At the same time, our glands do not produce as much lubricant to help with this process as they did in the past. Add to this that most people are on multiple medications which cause dryness mouth (xerostomia) and other mucous membranes which again retards the ability of the food to pass through the digestive tract. Now, because teeth are missing, our bodies are further challenged because food enters the digestive tract in bigger pieces which must be broken down and digested by an already compromised digestive system. It is obvious why people experience IBS (irritable bowel syndrome), GERD (Gastroesophageal reflux disease), etc. Replacing missing teeth is the first part of repairing this system, and the most predictable long-term way of reducing these problems.
Why do I care about bone loss?
Without alveolar bone (bone which holds or held teeth), your denture is loose, your bridge catches food (which can lead to decay and replacement), and you may lose the option of choosing an implant as bone houses the implant.
When teeth are removed from the jaw, the bone that supports the teeth tends to shrink over time. This process is called resorption and is a natural consequence of the loss of stimulation to the bone from the forces placed on the teeth. This is similar to atrophy or shrinkage of muscles when they are no longer used. Resorption of the alveolar bone (bone that supports the teeth) begins almost as soon as the tooth is removed and proceeds over time. The bone will lose both height and width from resorption.
The easiest way to prevent bone loss is to prevent it. If a tooth is removed and a graft or implant is placed( image without preservation and with preservation), the bone retention is highest. The longer the problem goes, the harder it is to fix. If you want to lose five pounds, it is easier than if you want to lose 55 pounds.
When multiple teeth are lost, with or without a prosthesis to replace them, significant loss of jaw bone can take place. This sometimes leads to difficulty wearing a removable denture due to lack of an adequate “ridge” upon which the denture can obtain stability. In the so-called “esthetic zone” of the mouth, where loss of ridge volume can be visibly apparent to the naked eye, this can lead to a cosmetic defect. As the bone resorbs, the gum which covers it also shrinks away, creating a concavity (depression in height and width) that can be unsightly as well as possibly promote food impaction under adjacent teeth.