When implants are used to secure a denture to your jaw bone, they are called ‘implant overdentures’. This name has been used because the denture sits on top of the implants. Implant overdentures can help people with severe jaw-bone loss to have a secure denture wearing experience. The procedure involves placing two or three implants usually into the lower jaw bone. Once the implants integrate into the bone, a denture is then made to fit over the top of the implants. Small clips are used to hold the dentures onto the implants.
The implant overdenture can still be removed from your mouth like a normal set of dentures to be cleaned and to give your gums a rest at night. The biggest difference is that they hold much better to your lower jaw compared with a conventional set of complete dentures. This will give you more confidence that your dentures will remain secure when eating and speaking.
While implants are highly successful, the likelihood of success depends on several factors. The amount of bone available to support the implant, your overall health, whether or not you smoke, and the quality of ongoing home care will all effect long-term success. If an implant fails to integrate in your bone, it can be removed under local anaesthetic. The site is allowed to heal before placing another implant into the same site. In general, implants placed into the front of the lower jaw, have the highest rate of survival (95%+). The upper jaw and the back of the lower jaw have traditionally had lower survival rates (88%+), however later research has shown that these survival rates have improved to above 90%. No matter where an implant is placed, there is always a small risk that the implant can fail and you must be aware of this prior to commencement of treatment. Most failures are seen within the first year. The bone and soft tissue repair rapidly and it is often possible to place another implant in the same site after a few months of healing at no extra cost to you.
Research has demonstrated that provided your gums remain healthy and you attend regular check ups, dental implants may remain integrated with bone in excess of 25 years. Many implants will remain integrated for life. The limiting factor for the survival of implant restorations is usually the overdenture that is placed on top. The most common maintenance issue of an overdenture is the clips coming loose and needing activation or tightening. Clips can come loose from the denture base, the abutment can come loose from the implant and all of the overdenture components will wear over time. After 5-6 years you will begin to notice wear on the false teeth themselves. Often the decision to replace or reline implant overdentures will rest with you and your ability to cope with wearing the implant overdentures. It is difficult to give an accurate estimate of exactly how long the implant overdenture will last, as this is dependant on many factors within and beyond our control. Most complications with materials tend to occur within the first year of service. The implants need to be brushed regularly to keep them clean and prevent plaque from building up on them. Provided the Implant Overdenture is maintained in a meticulous manner you should get many years of satisfactory service.
Implant overdentures can certainly improve the quality of life for those who cannot manage wearing conventional dentures, however over time some people forget how well they fit compared to a conventional denture. It has been well documented that the expectations of people wearing implant overdentures may increase over time and they still feel as if the lower denture is loose. The upper denture may also begin to feel loose as the lower denture becomes firm due to the improved tightness of the lower denture from the implants. However, overall, implant overdentures are a significant improvement when compared with conventional dentures.