Missing Teeth
Common causes of tooth loss
Congenital absence
It is not uncommon for a tooth or teeth to be congenitally absent. Most commonly, the primary (baby) tooth is present but there is no successor (permanent tooth) to replace it. Frequently, this will be apparent when the baby tooth exfoliates, or falls out (usually during adolescence). Often however, the baby tooth will remain in place and will function until it fails due to the loss of root support or other dental disease. At this point it will need to be removed.
Before placing an implant in the site of a congenitally absent tooth, it is important that your doctor verifies that there is not a tooth bud (a cyst-like structure) in the jawbone in that area. The most commonly missing teeth are maxillary (upper jaw) lateral incisors and premolars.
Trauma
Trauma can cause loss of teeth in a variety of ways. Teeth can be “knocked out” from trauma, such as a child falling off her bicycle and onto her face. Frequently however, trauma can affect the teeth in ways that do not manifest until months or years later. Root fracture may not be apparent until sometime later when infection develops. Sometimes after teeth have been traumatized they can be treated and appear to be doing well until many years later when root resorption becomes apparent. This occurs when the body turns against itself and causes cells to eat away at the root surface, often allowing bone to grow into the defect that has been created.
Trauma of a more pernicious order can also affect the dentition. Significant defects of the jaw bone, in addition to teeth, can occur as a result of trauma. This may be following surgery to remove a tumour from the mouth and/or jaws, or secondary to external trauma such as an automobile accident, other forms of blunt trauma or ballistic wounds. These types of trauma can often be compounded by significant loss of jaw bone volume, or even continuity, and could require other forms of surgery to reconstruct the jaw anatomy as well as provide for prosthetic tooth replacement.
Dental diseases
The most common reason for tooth loss is gum (periodontal) disease. This is essentially a localised infection in the gums and supporting structures of the teeth leading to loss of bone. This can progress to the point that teeth fall out on their own or are deemed beyond repair or are too compromised to be useful and must be extracted. Dental caries (decay) can also progress to the extent that teeth are beyond the ability to be restored in function. Decay can also lead to significant infection in the bone around the ends of the root(s) leading to necessary tooth extraction to prevent further infectious complications.
Lastly, teeth may crack or fracture in such a way that they cannot be maintained and must be removed. This can happen as the result of clenching and grinding habits (bruxism), or for mechanical reasons related to the lack of sufficient support from other teeth which causes extreme stress to the teeth that remain in function.
Loss of one or two teeth in a segment of your mouth can lead to drifting of neighbouring 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.
Missing teeth can be replaced in a variety of ways
Dental implants
A dental implant is essentially a substitute for a natural root and commonly it is screw or cylinder shaped. Each implant is placed into a socket carefully drilled at the precise location of the intended tooth. If an implant has a screw-thread on its outer surface it can be screwed into position and if it does not, it is usually tapped into place. The main aim during installation of any implant is to achieve immediate close contact with the surrounding bone. This creates an initial stability, which over time is steadily enhanced by further growth of bone into microscopic roughness on the implant surface.
In order to support replacement teeth, dental implants normally have some form of internal screw thread or post space that allows a variety of components to be fitted. Once fitted, these components provide the foundation for long-term support of crowns, bridges or dentures.
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.
Fixed bridge / Resin bonded bridge
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 10-12 years before requiring replacement. Replacement of fixed bridges often entails further treatment as the abutment or supporting teeth have been further compromised over time by advancing dental disease (such as cavities or periodontal bone loss).
In certain cases it is possible to use a resin bonded bridge which either have minimal preparation of the adjacent teeth or in some cases no preparation. The application of this treatment option is limited however if used with the correct planning this option of treatment can be very successful.
Dentures
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. Maxillary (upper jaw) full dentures also may be helped by suction between the denture and the underlying gum of your palate (roof of mouth).
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.
Emergency replacement
At 310 Dental we are able to provide emergency tooth replacement if the form of a fibre reinforced bridge which is a fixed option. This option can give you both function and aesthetics back in one session on a temporary measure while you are considering permanent options of treatment.